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Numerical investigation in chaos characteristics of macro-mixing efficiency of two-dimensional supersonic mixing layer

Coherent structures of two-dimensional supersonic turbulent mixing layers with the engineering background have been investigated numerically with large eddy simulation method. The chaos characteristics of transverse sections of mixing layer flowfield have been obtained through the analyses of two chaos characteristic parameters, Lyapunov exponent and correlation dimension. The results show that un

Characterization and Control of Multi-Cylinder Partially Premixed Combustion

Popular Abstract in Swedish Kraven på bränslesnåla och rena motorer har ökat under de senaste åren. Det började med att priset på olja steg kraftigt i början av 2000-talet. Kraven växte sedan ytterligare i kölvattnet av debatten kring växthuseffekten där koldioxid, en av de dominerande produkterna vid förbränning, spelar huvudrollen. Med tanke på att sänkt bränsleförbrukning rör både ekonomiska ocIn the last decade diesel combustion has developed in a new direction. Research has been carried out trying to prolong the ignition delay and enhance fuel/air premixing to avoid diffusion combustion as well as lowering the combustion temperature through use of EGR. One of these new combustion concepts is Partially Premixed Combustion (PPC). PPC is aimed to provide combustion with low smoke and NOx

Dual convolutional codes and the MacWilliams identities

A recursion for sequences of spectra of truncated as well as tailbitten convolutional codes and their duals is derived. The order of this recursion is shown to be less than or equal to the rank of the weight adjacency matrix (WAM) for the minimal encoder of the convolutional code. It is sufficient to know finitely many spectra of these terminated convolutional codes in order to obtain an infinitel

Mouse ApoM Displays an Unprecedented Seven-Stranded Lipocalin Fold: Folding Decoy or Alternative Native Fold?

Mouse apolipoprotein M (m-apoM) displays a 79% sequence identity to human apolipoprotein M (h-apoM). Both proteins are apolipoproteins associated with high-density lipoproteins, with similar anticipated biological functions. The structure of h-apoM has recently been determined by X-ray crystallography, which revealed that h-apoM displays, as expected, a lipocalin-like fold characterized by an eigh

On the existence of the Mazo-limit on MIMO channels

Mazo, in 1975, showed that the signaling rate of a linear modulation can be significantly higher than the maximum rate for orthogonal signaling without any loss of minimum square Euclidean distance. In subsequent literature the highest such rate is referred to as the Mazo-limit. In this letter we ask whether there exists a Mazo-limit also on MIMO channels. The answer is yes, but it applies to the

Water Tetramer, Pentamer, and Hexamer in Inert Matrices

The infrared spectrum of water, isolated in inert matrices, has been studied in the interval from 60 to 4000 cm(-1). Experiments with partially deuterated water combined with DFT (density functional theory) calculations have been used to investigate the structure of matrix-isolated water tetramer. A few, strong intermolecular fundamentals of the water tetramer have been observed. Mid-infrared band

Attosecond Electron Wave Packet Interferences

Attosecond pulses offer a new route to produce temporally localized electron wave packets (EWPs) that can easily be tailored by altering the properties of the attosecond pulses. In this thesis we will present different experiments, supported by theory, where attosecond EWPs are created in presence of a strong infrared (IR) field. By tuning the central frequency of the attosecond pulses and/or chan

Morph-specific and sex-specific temperature effects on morphology in the colour polymorphic damselfly Ischnura elegans

Colour polymorphic species with extensive ranges often exhibit large-scale geographic patterns of morph frequency variation. Because colour polymorphism is associated with correlated differences in multiple traits, such as thermal performance, a likely proximate explanation for such patterns is morph-specific responses to temperature variation. The colour polymorphic Blue-tailed damselfly Ischnura

Hornets Can Fly at Night without Obvious Adaptations of Eyes and Ocelli.

Hornets, the largest social wasps, have a reputation of being facultatively nocturnal. Here we confirm flight activity of hornet workers in dim twilight. We studied the eyes and ocelli of European hornets (Vespa crabro) and common wasps (Vespula vulgaris) with the goal to find the optical and anatomical adaptations that enable them to fly in dim light. Adaptations described for obligately nocturna

Oxygen-induced dynamics of nitrous oxide in water and off-gas during the treatment of digester supernatant.

Nitrous oxide (N2O) is a potent greenhouse gas and of special concern in wastewater treatment. It is formed in biological wastewater treatment under both aerobic and anaerobic conditions. A major reason for high N2O emissions is low oxygen concentration during nitrification. In this full-scale study of N2O emissions from a sequencing batch reactor for treating digester supernatant, the oxygen conc

Changing the Nexus: The Evolution and Renegotiation of Venture Capital Contracts

We study the evolution and renegotiation of the cash-flow rights that venture capitalists (VCs) obtain in their portfolio companies. When company performance between financing rounds is poor, subsequent contracts contain stronger VC cash-flow rights, and existing VCs tend to either give new VCs senior claims or forfeit their existing rights altogether. These results are consistent with the importa

Search for excited electrons and muons in root s=8 TeV proton-proton collisions with the ATLAS detector

The ATLAS detector at the Large Hadron Collider is used to search for excited electrons and excited muons in the channel pp -> ll* -> ll gamma, assuming that excited leptons are produced via contact interactions. The analysis is based on 13 fb(-1) of pp collisions at a centre-of-mass energy of 8 TeV. No evidence for excited leptons is found, and a limit is set at the 95% credibility level on the c

Effect of Acid Deposition on Quantity and Quality of Dissolved Organic Matter in Soil-Water.

The aim of this study was to explore how acid deposition may affect the concentration and quality of dissolved organic matter (DOM) in soil-water. This was done by a small-scale acidification experiment during two years where 0.5 × 0.5 m(2) plots were artificially irrigated with water with different sulfuric acid content, and soil-water was sampled using zero-tension lysimeters under the O-horizon

Debating credibility: The shaping of information literacies in upper secondary schools

Abstract in UndeterminedPurpose – The article concerns information literacies in an environment characterised by the two partly competing and contradictory cultures of print and digital. The aim of the paper is to provide a better understanding of the ways in which students assess the credibility of sources they use in school, with a particular interest in how they treat participatory genres.Desig

Theoretical and experimental analyses of drop deformation and break-up in a scale model of a high-pressure homogenizer

High-pressure homogenizers (HPHs) are used to create sub-micron emulsions in low-viscosity fluids. As the flow in a real HPH is very extreme, with gaps ranging from 10 to 100 pm and high velocities, it is almost impossible to visualize the drop break-up process. In this study a plastic scale model of a HPH was made, allowing the visualization of drop deformation and break-up. Great care was taken