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Natural gas and hydrogen enriched natural gas has been tested as fuels together with diesel oil and RME in a single cylinder Scania research engine. The gas was introduced as port injection while the diesel was introduced as early direct injection. Because the gas was premixed with air before combustion and the diesel was injected early in the compression stroke, the engine ran close to HCCI mode.

In HCCI you do not have the same control of the combustion like in SI and Diesel engines. Controlling the start of a combustion event is a difficult task and requires feedback from previous cycles. This feedback can be retrieved from ion current measurements. By applying a voltage over the spark gap, ions will lead a current and a signal that represents the combustion in the cylinder will be retri

Utilization of an ethanol driven, combustion-based power generator promises high-efficiency combustion in diesel-like engines and avoids problems connected to shrinking supplies of fossil fuels since fuels like ethanol or dimethyl ether can be produced from renewable resources. Fuel injection into such generator through a piezoelectric micro mass flow controller (MMFC) features low power consumpti

A piezoelectric micro mass flow controller (MMFC) for liquid fuel injection into a mini-HCCI-motor for power generation is introduced. Piezoelectric actuation ensures negligible power consumption for fuel injection allowing self-sustaining operation. A pressurized fuel tank is connected to the MMFC which is designed like a normally-closed, on-/off-operating valve. Integrated piezoresistors are use

This work has focused on studying the in-cylinder pressure fluctuations caused by rapid HCCI combustion and determine what they consist of. Inhomogeneous autoignition sets up pressure waves traversing the combustion chamber. These pressure waves induce high gas velocities which causes increased heat transfer to the walls or in worst case engine damage. In order to study the pressure fluctuations a

The integration of metallic plasmonic nanoantennas with quantum emitters can dramatically enhance coherent harmonic generation, often resulting from the coupling of fundamental plasmonic fields to higher-energy, electronic or excitonic transitions of quantum emitters. The ultrafast optical dynamics of such hybrid plasmon–emitter systems have rarely been explored. Here, we study those dynamics by i

Metal halide perovskite semiconductors often exhibit photoluminescence blinking and flickering when luminescence of individual small nano- or even microcrystals is monitored. The nature of these fluctuations is not well understood but must be related to the presence of metastable non-radiative recombination channels and efficient charge migration in these materials. Here we report on the excitatio

BACKGROUND: The PBDX/XG gene encoding the Xga blood group antigen was described in 1994, but the genetic determinant of XG expression on RBCs was reported only in 2018. However, the frequencies of Xg(a-) individuals could not explain the rarity of anti-Xga makers. We therefore sought to elucidate the molecular basis of the Xg(a-) phenotype in people producing anti-Xga .STUDY DESIGN AND METHODS: Tw

The crystal structure of a material has a large impact on the electronic and material properties such as band alignment, bandgap energy, and surface energies. Au-seeded III–V nanowires are promising structures for exploring these effects, since for most III–V materials they readily grow in either wurtzite or zinc blende crystal structure. In III–Sb nanowires however, wurtzite crystal structure gro

Data on longitudinal lung function change in the elderly are scarce. Uncertainty remains about whether to use absolute or relative change and how it relates to subject demographics.We studied absolute and relative forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) change in a population-based geriatric sample using a repeated measurements model adjusted for age, sex, smoking ha

Purpose: Speech signal degradation such as a voice disorder presented in quiet or in combination with multi-talker babble noise could affect listening comprehension in children with hearing impairment. This study aims to investigate the effects of voice quality and multi-talker babble noise on passage comprehension in children with using cochlear implants (CIs) and/or hearing aids (HAs). It also a

Battery thermal management (BTM) plays a significant role in the safety and reliability of autonomous underwater vehicles (AUV) at higher speeds. In this study, a nanoparticle/phase change material (nano-PCM) composite is proposed for the BTM of an AUV. The effects of nanoparticle loading percentage (φ = 5, 10, and 15%) and nanoparticle filling range (α = 30, 60, 90, and 120°) on the battery tempe

The gas flow field design plays a vital role in the cell performance of proton exchange membrane fuel cells, especially at high current densities. In this study, wavy flow channels are designed and adopted on the cathode side to enhance the mass transport process. Results demonstrate that the wavy flow channels proposed in this paper significantly improve cell performance at high current densities

For internal cooling of a turbine blade, various advanced rib turbulators can markedly contribute to the heat transfer enhancement while suffering a great increase in pressure loss. In those designs, ribs with the same configuration are periodically and evenly mounted on the channel wall. In this context, this work proposes a hierarchical design concept to optimize the rib arrangement with the des

OBJECTIVE: Few studies address results from use of new technology and patient participation in hypertension management. The PERHIT Study is a multicentre randomised controlled trial with the aim to evaluate the effects of a person-centred approach using a web-based, interactive self-management system through the patient´s own mobile phone on blood-pressure and well-being. Primary aim is the degree

This thesis addresses how graphene can be a valuable asset for surface science studies. Using a combination of X- ray photoelectron spectroscopy, scanning tunneling microscopy, and low-energy electron diffraction, we take advantage of graphene’s sensitivity to changes in its chemical environment to obtain an atomic scale understanding of different reactions occurring above and below the film.As a

Spontaneous magnetic alignment is the simplest known directional response to the geomagnetic field that animals perform. Magnetic alignment is not a goal directed response and its relevance in the context of orientation and navigation has received little attention. Migratory songbirds, long-standing model organisms for studying magnetosensation, have recently been reported to align their body with

To investigate self-reported cold sensitivity and functional disability after a repaired digital nerve injury. We identified 3204 individuals operated with digital nerve repair in the Swedish national quality registry for hand surgery (HAKIR). Patient-reported symptoms, including cold sensitivity and perceived disability, were examined using two questionnaires (HQ-8 and QuickDASH), three and 12 mo

The oxido-bridged diiron(III) complex [Fe2(μ-O)(μ-OAc)(DPEAMP)2](OCH3) (1), based on a new unsymmetrical ligand with an N4O donor set, viz. [2-((bis(pyridin-2-ylmethyl)amino)methyl)-6-((ethylamino)methyl)-4-methylphenol (HDPEAMP)], has been prepared and characterized by spectroscopic methods and X-ray crystallography. The crystal structure of the complex reveals that each Fe(III) ion is coordinate