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Induction heating of carbon fiber composites: Investigation of electrical and thermal properties

Carbon fiber reinforced plastics, CFRP, are attractive materials not only because of their strength and stiffness but also because of their electrical conductivity and high thermal conductivity and diffusivity. One application where induction heating of CFRP is particularly interesting is tools for fast thermal cycling, beneficial inmany industrial processes, for example in composite manufacturingCarbon fiber reinforced plastics, CFRP, are attractive materials not only because of their strength and stiffness but also because of their electrical conductivity and high thermal conductivity and diffusivity. One application where induction heating of CFRP is particularly interesting is tools for fast thermal cycling, beneficial in many industrial processes, for example in composite manufacturin

Refugee Matching as a Market Design Application

This note contains a few brief remarks on the similarities and differences between some standard market design applications (e.g., kidney exchange and school choice) and the refugee assignment problem. The main conclusion is that the refugee assignment problem is more complex in some dimensions than many of the standard market design applications. Consequently, classical mechanisms cannot be used

Give Voice - At Hand

The installation is based on two elements, a re-used tape recorder and a pair of aged wooden planks. The planks are mounted to form a table on which the tape recorder is placed. The sound from the tape recorder is based on field recordings from the area around the municipality Taivalkoski in Northeastern Finland. The tape recorder has formerly been used at The Department of Ethnology at Lund Unive

Acoustofluidic hematocrit determination

Hematocrit (HCT) measurements of blood from patients, blood donors and athletes are routinely performed on a daily basis. These measurements are often performed in centralized hospital labs by whole blood analyzers, which leads to long time-to-result. On site measurements, based on centrifugation can be done, but these assays require manual handling, are slow and can just measure HCT in contrast t

Acoustic separation of bacteria from blood cells at high cell concentrations enabled by acoustic impedance matched buffers

We have developed a method to separate bacteria from red and white blood cells (henceforth collectively called blood cells) using acoustophoresis, for subsequent PCR detection. To maximize throughput, we have now investigated the effect of increased cell concentration on the separation. Increasing the blood concentration drastically decreases bacteria recovery, but we show that this can be remedie

Self-Scanning and Self-Control: A Field Experiment on Real-Time Feedback and Shopping Behavior

Payment and checkout at retail stores is increasingly being replaced by automated systems. One recent technological invention in this area is mobile self-scanning in which customers carry a mobile scanner while shopping. Mobile self-scanners give real-time feedback on spending. The device increases price saliency and enables customers to keep track of the total amount spent. Using a field experime

Integrated acoustic sample preparation for rapid sepsis diagnostics

We present a novel, integrated microfluidic system based on acoustophoretic cell-handling that detects bacteria in whole blood in less than 2 hours, substantially faster than current standard methods for detection of sepsis-causing bacteria. Bacteria are acoustically separated from 1 ml blood, enriched by acoustic trapping and finally detected using a dry-reagent PCR-chip.

An electrochromatography chip with integrated waveguides for UV absorbance detection

A silicon-based microchip for electrochromatographic separations is presented. Apart from a microfluidic network, the microchip has integrated UV-transparent waveguides for detection and integrated couplers for optical fibers on the chip, yielding the most complete chromatography microchip to date in terms of the integration of optical components. The microfluidic network and the optical component

Simultaneous native UV fluorescence and absorbance detection for microchip electrophoresis using integrated waveguides

This paper reports simultaneous detection of ultra violet (UV) absorbance and native UV-excited fluorescence in an electrophoresis microchip using UV transparent integrated waveguides. Absorbance detection enables detection of a wide range of analytes. When exposed to UV light, some compounds also exhibit native fluorescence, which is here detected simultaneously. Calibration curves were measured

Electrophoresis microchip with integrated waveguides for simultaneous native UV fluorescence and absorbance detection

Simultaneous label-free detection of UV absorbance and native UV-excited fluorescence in an electrophoresis microchip is presented. UV transparent integrated waveguides launch light at a wavelength of 254 nm from a mercury lamp along the length of a 1-mm long detection cell. Transmitted UV light is collected by another waveguide in the opposite end of the detection cell, while visible fluorescence

Cyclic olefin polymers : Emerging materials for lab-on-a-chip applications

Cyclic olefin polymers (COPs) are increasingly popular as substrate material for microfluidics. This is due to their promising properties, such as high chemical resistance, low water absorption, good optical transparency in the near UV range and ease of fabrication. COPs are commercially available from a range of manufacturers under various brand names (Apel, Arton, Topas, Zeonex and Zeonor). Some

Acoustic trapping efficiency of nanoparticles and bacteria

In this paper we present a method to characterize the acoustic trapping efficiency of nanoparticles and bacteria when using seeding particles. Through the use of fluorescent microscopy and video analysis, single particles/bacteria were counted as they entered the acoustic trap at different flow focusing ratios and by comparing the amount of trapped objects to the amount of objects that were lost f

Acoustophoresis separation of bacteria from blood cells for rapid sepsis diagnostics

We present a significantly improved acoustophoresis method to separate bacteria from red and white blood cells. As much as 98% of the bacteria were recovered, while only 0.06 % of the red and white blood cells remained. This 1600-fold relative enrichment was achieved by adjusting the center medium density, tightly controlling the chip temperature and stabilizing the fluid flows. This is a crucial

Continuous acoustic sorting of E. Coli and G. Lamblia in drinking water

This paper presents an acoustofluidic chip for the sorting of bacteria from protozoa in water using standing acoustic waves. The size-based acoustophoretic sorting method provides a means for sample pre-concentration, which is vital for real-time, on-site monitoring of drinking water quality and preventing outbreak of waterborne diseases. In practice, high throughput and high recovery pre-concentr

Build your own soil : exploring microfluidics to create microbial habitat structures

Soil is likely the most complex ecosystem on earth. Despite the global importance and extraordinary diversity of soils, they have been notoriously challenging to study. We show how pioneering microfluidic techniques provide new ways of studying soil microbial ecology by allowing simulation and manipulation of chemical conditions and physical structures at the microscale in soil model habitats.The

Manure management and public health : Sanitary and socio-economic aspects among urban livestock-keepers in Cambodia

Livestock manure is a valuable source of nutrients for crop production, but can also pose a public health hazard and have negative environmental impacts. This study investigated manure management practices among urban and peri-urban livestock keepers in Cambodia, to identify risk behaviours and socio-economic aspects associated with the handling of manure. A survey including 204 households was con

O/W emulsions stabilized by OSA-modified starch granules versus non-ionic surfactant : Stability, rheological behaviour and resveratrol encapsulation

Resveratrol is a natural phenol with many positive effects for human health. However it is a photosensitive molecule with geometric isomerism, easily oxidised with short biological half-life and rapid metabolism and elimination. Thus, encapsulation of resveratrol is necessary. It has low solubility in water and in most of common oils. The goal of this work was to prepare oil-in-water emulsion stab

Sustainability of mega water diversion projects : Experience and lessons from China

Water availability and water demand are not evenly distributed in time and space. Many mega water diversion projects have been launched to alleviate water shortages in China. This paper analyzes the temporal and spatial features of 59 mega water diversion projects in China using statistical analysis. The relationship between nine major basins is measured using a network analysis method, and the as