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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

Only one fifth of children aged 11–17 years are physically active for 60 min (min)/day. As physical activity (PA) levels track from childhood to adulthood, it is important to establish healthy PA behavior early in life. This study aims to evaluate whether daily school PA is associated with objectively measured PA independently of other socioecological factors. This study includes 209 children (120

Nanowires require surface passivation due to their inherent large surface to volume ratio. We investigate the effect of embedding InP nanowires in different oxides with respect to surface passivation by use of electron beam induced current measurements enabled by a nanoprobe based system inside a scanning electron microscope. The measurements reveal remote doping due to fixed charge carriers in th

Compared to petroleum diesel, renewable diesel fuels and exhaust aftertreatment systems can reduce primary exhaust emissions that are hazardous to human health and the environment. Secondary aerosol emissions which form upon atmospheric processing have, however, been less studied. This study aimed to quantify the impacts of replacing petroleum diesel with renewable fuels (hydrotreated vegetable oi

Recent studies have shown increased concentration of fetal hemoglobin (HbF) in pre-eclamptic women. Plasma hemopexin (Hpx) and alpha-1-microglobulin (A1M) are hemoglobin scavenger proteins that protect against toxic effects of free heme released in the hemoglobin degradation process. We used an enzyme-linked immunosorbent assay to analyze maternal plasma Hpx and A1M concentrations at 12–14, 18–20

Studies of thermally induced transport in nanostructures provide access to an exciting regime where fluctuations are relevant, enabling the investigation of fundamental thermodynamic concepts and the realization of thermal energy harvesters. We study a serial double quantum dot formed in an InAs/InP nanowire coupled to two electron reservoirs. By means of a specially designed local metallic joule-

Increasing demand for detecting single molecules in challenging environments has raised the bar for the fluorophores used. To achieve better resolution and/or contrast in fluorescence microscopy, it is now essential to use bright and stable dyes with tailored photophysical properties. While long fluorescence lifetime fluorophores offer many advantages in time-resolved imaging, their inherently low

Solar cells incorporating metal-halide perovskite (MHP) semiconductors are continuing to break efficiency records for solution-processed solar cell devices. Scaling MHP-based devices to larger area prototypes requires the development and optimization of scalable process technology and ink formulations that enable reproducible coating results. It is demonstrated that the power conversion efficiency

Over the last several decades, the light-harvesting protein complexes of purple bacteria have been among the most popular model systems for energy transport in excitonic systems in the weak and intermediate intermolecular coupling regime. Despite this extensive body of scientific work, significant questions regarding the excitonic states and the photo-induced dynamics remain. Here, we address the

Monolithic integration of III-V semiconductors with Silicon technology has instigated a wide range of new possibilities in the semiconductor industry, such as combination of digital circuits with optical sensing and high-frequency communication. A promising CMOS compatible integration process is rapid melt growth (RMG) that can yield high quality single crystalline material at low cost. This paper

Mitochondrial dysfunction is an important factor of the aging process and may play a key role in various diseases. Mitochondrial DNA copy number (mtDNA-CN) is an indirect measure of mitochondrial dysfunction and is associated with type 2 diabetes mellitus (T2DM); however, whether mtDNA-CN can predict the risk of developing T2DM is not well-known. We quantified absolute mtDNA-CN in both prevalent a

The efficiency of bulk heterojunction (BHJ) based organic solar cells is highly dependent on the morphology of the blend film, which is a result of a fine interplay between donor, acceptor, and solvent during the film drying. In this work, a versatile set-up of in situ spectroscopies is used to follow the morphology evolution during blade coating of three iconic BHJ systems, including polymer:full

There is concern that immunotoxic environmental contaminants, particularly perfluoroalkyl substances (PFAS), may play a role in the clinical course of COVID-19 and epidemiologic studies are needed to answer if high-exposed populations are especially vulnerable in light of the ongoing pandemic. The objective was, therefore, to determine if exposure to highly PFAS-contaminated drinking water was ass

Lead-free halide perovskites have triggered interest in the field of optoelectronics and photocatalysis because of their low toxicity, and tunable optical and charge-carrier properties. From an application point of view, it is desirable to develop stable multifunctional lead-free halide perovskites. We have developed a series of Cs2PtxSn1−xCl6 perovskites (0≤x≤1) with high stability, which show sw

Dion–Jacobson (DJ)-type 2D halide perovskites present superior environmental stability and a narrower bandgap, yet a contradiction between charge transport and stability remains to be resolved. Herein, it is shown that both symmetry and substitution of the organic spacer in DJ perovskites synergistically direct the narrow interlayer spacing, staggered spacer alignment, and regular phase arrangemen