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Characterization of an Electrical Sensor for Combustion Diagnostics

Popular Abstract in Swedish Joniseringssensorn är en elektrisk sensor för diagnostik i förbränningsmotorer. Sensorn används idag för att till exempel detektera knack. Sensorn bygger på att energifrigörelsen i motorn leder till jonisering av olika ämnen, vilket betyder att gasens lednigsförmåga ökar. Detta kan mätas genom att lägga en spänning över tändstiftsgapet under förbränningen och registreraThe ionization sensor is an electrical probe for diagnostics in internal combustion engines. The combustion process affects the electrical properties of the gas in the cylinder. Thus the sensor signal contains copious information about the conditions in the combustion chamber. A thorough characterization of the sensor makes it possible to take advantage of a larger portion of this information for

High spectral resolution solar absorption measurements of ethylene (C2H4) in a forest fire smoke plume using HITRAN parameters: Tropospheric vertical profile retrieval

The tropospheric mixing ratio profile of ethylene (C2H4) has been retrieved from a high spectral resolution ground-based infrared solar absorption spectrum. The spectrum was recorded during intense fires in New South Wales, Australia on January 1, 2002, and was analyzed with the C2H4 spectral parameters added to the 2000 HITRAN compilation. Absorption by C2H4 in the smoke-affected spectrum extends

Electric control of spin polarization orientation in a magnetic-electric barrier structure

We investigate spin-dependent transport properties of two-dimensional electron systems modulated by both the stray field from a ferromagnetic metal (FM) stripe and the electrostatic potential (EP) provided by two normal metal Schottky stripes which sandwich the FM stripe. The EP consists of a single barrier and a single well. By switching the gate voltages applied to the Schottky stripes, the barr

Företagets agerande i förhållande till naturbelastningen: Hur företaget möter myndigheternas miljökrav

Popular Abstract in Swedish Denna studie behandlar huvudsakligen hur företagen väljer att anpassa sig till myndigheternas krav utifrån miljöskyddslagen. Undersökningen fångar en viss historisk tidpunkt då lagstiftning och myndigheter har en viktig betydelse. Det är en mycket dramatisk fas av den miljöekonomiska utvecklingen. I samhället har man inte tidigare artikulerat miljökraven på ett sådant sThis study primarily focuses on the ways in which companies choose to adapt themselves to the demands of the authorities as based on the Swedish environmental protection act. The time during which the burden upon nature became a serious, important question for companies is a very dramatic phase of a historical process. Before the arrival of more comprehensive legislation, no loads upon nature were

Coordinated Multi-Stage Inventory Systems with Stochastic Demand

This thesis is based on six scientific papers providing different methods for coordinated inventory control in supply chains. The main focus is on supply chains in connection with distribution of products to customers. Two different problem areas are considered. One problem area concerns coordination by centralized optimization of local decision rules. It is assumed that the decision system is ce

Modeling of high-temperature desulfurization by Ca-based sorbents

Models for estimating the sulfation of CaO at high temperature are presented. Short-residence-time sulfation is described by a pore size distribution model and long-residence-time sulfation by a particle expansion model. The calculations made agree well with experiments carried out on three different limestones in a TGA, a volumetric reactor and an entrained flow reactor. The pore size distributio

The Multi-Pitch Estimation Problem: Some Solutions

n this paper, we formulate the multi-pitch estimation problem and propose a number of methods to estimate the set of fundamental frequencies. The methods, which are based on nonlinear least-squares, multiple signal classification (MUSIC) and the Capon principles, have in common the fact that the multiple fundamental frequencies are estimated by means of a one-dimensional search. The statistical pr

Estimating soil solution electrical conductivity from time domain reflectometry measurements using neural networks

Time domain reflectometry (TDR) is a widely used method for measuring the dielectric constant (K-a) and bulk electrical conductivity (sigma(a)) in soils. The TDR measured sigma(a) and K-a can be used to calculate the soil solution electrical conductivity, sigma(w.) The sigma(w), in turn, can be related to the concentration of an ionic tracer. Several models of the sigma(w)-sigma(a)-K-a relationshi

Clinical expression of X-linked retinitis pigmentosa in a Swedish family with the RP2 genotype

PURPOSE: To examine the clinical phenotype with emphasis on electroretinograms and visual fields in a Swedish family with X-linked retinitis pigmentosa (XLRP) type 2 (RP2), and compare it with Swedish XLRP families with the RP3 genotype. METHODS: Three affected brothers and their carrier mother were examined clinically and with kinetic perimetry, dark adaptation thresholds, and full-field electror

Hybridisation between great reed warblers Acrocephalus arundinaceus and clamorous reed warblers A. stentoreus: morphological and molecular evidence.

We present morphological and molecular evidence of the occurrence of hybrids between great reed warblers Acrocephalus arundinaceus and clamorous reed warblers A. stentoreus in Kazakhstan where both species breed. Three males and one female of 249 examined individuals had wing characteristics that were intermediate between the parental species. Molecular analyses of a nuclear microsatellite locus a

Darmin is a novel secreted protein expressed during endoderm development in Xenopus.

Endoderm development is an area of intense interest in developmental biology, but progress has been hampered by the lack of specific markers for differentiated endodermal cells. In an unbiased secretion cloning screen of Xenopus gastrula embryos we isolated a novel gene, designated Darmin. Darmin encodes a secreted protein of 56 kDa containing a peptidase M20 domain characteristic of the glutamate

Nitric oxide independent activation of guanylate cyclase by YC-1 causes erectile responses in the rat.

PURPOSE: Activation of soluble guanylate cyclase with a subsequent increase in intracellular levels of cyclic guanosine monophosphate is necessary for normal erection. In vascular tissue 3(5'-hydroxymethyl-2'-furyl-1-benzyl indazole (YC-1) (Abbott Laboratories, North Chicago, Illinois) has been shown to stimulate soluble guanylate cyclase independent of nitric oxide. We studied whether YC-1 modula

Effect of surface grafted polymers on the adsorption of different model proteins

Adsorption of a model protein to a surface with end-grafted polymers was studied by Monte Carlo simulations. In the model the effect on protein adsorption in the presence of end-grafted polymers was evaluated by calculating the change in free energy between an end-grafted surface and a surface without polymers. The change in free energy was calculated using statistical mechanical perturbation theo

Hericenols A-D and a chromanone from submerged cultures of a Stereum species

Extracts of submerged cultures of a Stereum species afforded four new pentasubstituted phenolic compounds, named hericenols A, B, C, and D (1-4), 6-hydroxymethyl-2,2-dimethylchroman-4-one (5) and the known erinapyrone C. Hericenol A (1) showed weak antimicrobial activity while hericenol C (3) was weakly cytotoxic. The structures of the metabolites were determined by spectroscopic techniques. (C) 2