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Thermodynamic Simulation of HCCI Engine Systems

Popular Abstract in Swedish Avhandlingen omfattar förutom en kort inledning, i huvudsak två delar: (1) Beskrivning av teorin bakom ett datorbaserat verktyg för simulering av termodynamiken i ett motorsystem, där främst motorer med Homogen Kompressionsantändning (Homogeneous Charge Compression Ignition, HCCI) avses. Med system avses förutom själva motorn, turboladdare, laddluftkylare, insug och avgThis thesis focuses on engine system simulation using thermodynamics and chemical kinetic models to investigate the performance and efficiency of Homogeneous Charge Compression Ignition (HCCI) engines for stationary applications. It includes the development of software as well as models for engine, turbocharger, intercooler, inlet and exhaust manifolds, wastegate valve, inlet air humidifier, inle

Corporate Social Responsibility and Development : Case of the Chad-Cameroon Oil Pipeline Project

As society today increasingly understands the impact of transnational corporate operations, an increasing recognition on the part of corporations of their responsibility for social and environmental well being of people in poor countries appears. The norm - Corporate Social Responsibility (CSR) grew out of such logic. The present study explores the extent to which CSR can be expected to contribute

Effective properties of heterogeneous materials with applications in electromagnetics

Composite materials, i.e, mixtures of two or more materials, are commonly used in industry, because they often have outstanding properties in comparison with the original materials. In many cases the inhomogeneities are on a very fine scale, which makes it difficult to perform a full numerical simulation of the material. On the fine scale we have rapid oscillations in the material parameters, but

Effects of type of packaging material on shelf-life of fresh broccoli by means of changes in weight, colour and texture

Five polymeric films were studied to determine their ability to retain the colour, weight and texture of broccoli (Brassica oleracea L. var. Italica "Monterey"). The materials were oriented polypropylene (OPP), polyvinyl chloride (PVC) and two different low-density polyethylenes (LDPE), one of which contained a sachet reported to absorb ethylene. The broccoli was packaged and stored at 4 and 10 de

Isolation of obligate anaerobic rumen bacteria capable of degrading the neurotoxin beta-ODAP (beta-N-oxalyl-L-alpha,beta-diaminopropionic acid) as evaluated by a liquid chromatography/biosensor analysis system

Six pure strains of obligate anaerobes capable of degrading the toxin beta-N-oxalyl-L-alpha, beta-diaminopropionic acid (beta-ODAP) contained in grass pea (Lathyrus sativus) have been isolated from cow rumen. The new isolates were identified as Megasphaera elsdenii (five different genotypes) and Clostridium bifermentans using 16S rDNA analysis. The beta-ODAP degrading efficiency of the isolates wa

Coherent soft particle production in Z decays into three jets

Low-energy particle production perpendicular to the event plane in three-jet events produced in Z decays in e(+)e(-) annihilation is measured and compared to that perpendicular to the event axis in two-jet events. The topology dependence of the hadron production ratio is found to agree with a leading-order QCD prediction. This agreement and especially the need for the presence of a destructive int

Knut Wicksell, Gustav Cassel, Eli Heckscher, Bertil Ohlin and Gunnar Myrdal on the Role of the Economist in Public Debate

In Swedish public debate, economists have been more influential than any other category of social scientists. We examine the views of five great Swedish economists on the role of the university economist in the public arena. What did they say about scholarly objectivity and value judgements, about political commitment and educating the people? The five economists are Knut Wicksell, Gustav Cassel,

Mixed infection with two types of hepatitis C virus is probably a rare event

A search for the simultaneous presence of two hepatitis C virus (HCV) types in sera of a group of chronically infected intravenous drug users, hemodialysis patients and hemophiliacs from Sweden and Russia was performed with two genotyping methods based on the use of type-specific primers from core and NS4 regions of the viral genome. An important feature of NS4 based assay is that type-specific pr

Sympathetic and parasympathetic neuropathy are frequent in both type 1 and type 2 diabetic patients.

OBJECTIVE—The aim of this study was to evaluate the frequency of sympathetic versus parasympathetic neuropathy among type 1 and type 2 diabetic patients. RESEARCH DESIGN AND METHODS—There were 43 patients with type 1 and 17 with type 2 diabetes who were investigated. Sympathetic nerve function was assessed by measurement of the vasoconstriction (VAC) index by laser Doppler perfusion imaging of a

Laminin Isoforms in fetal and adult human adrenal cortex

Laminin has been proposed to influence the function of human adrenal cortex. We have studied the distribution of laminin (Ln) chains using immunofluorescence in human fetal and adult adrenal cortex. In the fetal gland Ln alpha2- and alpha5-chains were weakly expressed in the definitive zone, whereas Ln alpha4-, beta1-, and gamma1-chains occurred around vessels. In the adult gland, Ln alpha2-, alph

NMR spectroscopy in inhomogeneous B-0 and B-1 fields with non-linear correlation

Resolved NMR spectra from samples in inhomogeneous B-0 and B-1 fields can be obtained with the so-called "ex situ" methodology, employing a train of composite or adiabatic z-rotation RF pulses to periodically refocus the inhomogeneous broadening during the detection of the time-domain signal. Earlier schemes relied on a linear correlation between the inhomogeneous B0 and B, fields. Here the pulse

9-Anthraldehyde acetals as protecting groups.

Anthraldehyde acetals can be introduced regioselectively to carbohydrates in high yields. Advantages over conventional acetal protecting groups are increased crystallinity and strong absorbance and fluorescence which facilitate purification and reaction monitoring. The anthraldehyde acetals can be deprotected selectively in the presence of benzylidene acetals and can be cleaved regioselectively to

Leptin inhibits apolipoprotein M transcription and secretion in human hepatoma cell line, HepG2 cells.

Apolipoprotein M (apoM) is a novel apolipoprotein presented mostly in high-density lipoprotein (HDL) in human plasma. Previously we have reported that both leptin and leptin receptor are essential for apoM expression in vivo. The expression of apoM is lower in the leptin deficient (ob/ob) mouse and leptin receptor deficient (db/db) mouse than in the normal mouse. In the present study, however, we

A tephra-based correlation between the Faroe Islands and the Norwegian Sea raises questions about chronological relationships during the last interglacial

Marine ash zones from the last interglacial period have been described from cores from the North Atlantic and an ash zone from the middle part of the interglacial has been observed in connection with a major cooling event. Here we present evidence for a coeval ash zone in a terrestrial site on the Faroe Islands. The investigated sediments are correlated with the upper part of oxygen isotope stage

On-line capillary based quantitative analysis of a heterocyclic amine in human urine

A high through-put miniaturised separation-quantification method for the heterocyclic aromatic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in urine was developed. The limit of detection was of 0.65 fmol (0.14 pg) injected or 65 pM. Heterocyclic aromatic amines are mutagenic and carcinogenic compounds formed at low levels in protein-rich food during cooking. Due to the low concentr

Thermodynamic Modelling and Performance of Combined Solid Oxide Fuel Cell and Gas Turbine Systems

Popular Abstract in Swedish Fasoxidbränsleceller (eng. SOFC) är en keramisk bränslecellstyp som arbetar vid höga temperaturer. Genom att utnyttja energin hos avgaserna från en SOFC i en annan kraftvärmeprocess kan man erhålla ett s.k. hybridsystem som når höga verkningsgrader. Ett koncept som studerats i denna avhandling är en SOFC i kombination med en gasturbincykel (SOFC/GT). Eftersom bränslecelSolid oxide fuel cells (SOFCs) are a ceramic type of fuel cell operating at elevated temperatures. By utilising the thermal energy from the SOFC in a heat engine, a hybrid cycle with high performance can be achieved. One promising concept is a pressurised SOFC in combination with a recuperated gas turbine cycle. The fuel cell, being the more efficient power generator of the two, represents the maj