| 11. |
- Nilsson, Erik, 1976, et al.
(författare)
-
Poling and characterization of piezoelectric polymer fibers for use in textile sensors
- 2013
-
Ingår i: Sensors and Actuators A-Physical. - : Elsevier S.A.. - 0924-4247 .- 1873-3069. ; 201, s. 477-486
-
Tidskriftsartikel (refereegranskat)abstract
- This study reports on the poling and characteristics of a melt-spun piezoelectric bicomponent fiber with poly(vinylidene fluoride) (PVDF) as its sheath component and a conductive composite with carbon black (CB) and high density polyethylene (HDPE) as its core component. The influence of poling conditions on the piezoelectric properties of the fibers has been investigated. The poling parameters temperature, time and poling voltage have been varied and the piezoelectric effect of both contact- and corona-poled yarns have been evaluated. The results show that a high piezoelectric effect is achieved when the poling voltage is high as possible and the poling temperature is between 60°C and 120°C. It was also shown that permanent polarization is achieved in a time as short as 2 second in corona-poled fibers. A yarn exposed to a sinusoidal axial tension of 0.07% strain (the corresponding force amplitude was 0.05 N) shows an intrinsic voltage output of 4 V. The mean power from a 25 mm length of yarn is estimated to be 15nW. To demonstrate the fibers sensor properties, they are woven into a textile fabric from which a force sensor is manufactured and used to detect the heartbeat of a human.
|
|
| 12. |
- Oko, Asaf, et al.
(författare)
-
Measurements and dimensional scaling of spontaneous imbibition of inkjet droplets on paper
- 2016
-
Ingår i: Nordic Pulp & Paper Research Journal. - : SPCI. - 0283-2631 .- 2000-0669. ; 31:1, s. 156-169
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate theoretically and experimentally the spontaneous imbibition of water based inkjet formulations utilizing paper capillary rise and imbibition of inkjet drops. We approximate the paper structure to a two dimensional anisotropic porous material, and using Darcy's law as a base, we derive dimensionless groups that scale drop imbibition. This derivation is based on a previous dimensional scaling of drop imbibition on thick isotropic porous material. We apply this scaling to a paper substrate by measuring the average drop imbibition rate, and perform paper capillary rise experiments to obtain the average system parameters required for the scaling. The results suggest that this approach is a valuable tool to predict drop imbibition rates on paper. We then continue and perform the same sets of experiments on a different paper with similar structure that is surface treated (surface sized) with CaCl2 salt, an additive that is known to improve print quality. We find that due to rapid aggregation of the colorant ink by the CaCl2, the imbibition rate is slowed down in the capillary rise experiments, i.e., on much larger scales compared to a single inkjet drop. However, the presence of CaCl2 has only minor effect over the average imbibition rates of single drops. Imbibition rates on the CaCl2 surface sized paper did not give adequate scaling as a result of the fact that the aggregation was not included the theoretical assumptions behind the scaling.
|
|
| 13. |
|
|
| 14. |
- Skagestad, Ragnhild, 1978, et al.
(författare)
-
GCCSI Webinar: Cutting Cost of CO2 Capture in Process Industry (CO2stCap) Project overview & first results for partial CO2 capture at integrated steelworks
- 2017
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- GCCSI Webinar: Cutting Cost of CO2 Capture in Process Industry (CO2stCap) Project overview & first results for partial CO2 capture at integrated steelworks This publication has the format of a webinar: The CO2StCap project is a four year initiative carried out by industry and academic partners with the aim of reducing capture costs from CO2 intensive industries (more information here). The project, led by Tel-Tek, is based on the idea that cost reduction is possible by capturing only a share of the CO2 emissions from a given facility, instead of striving for maximized capture rates. This can be done in multiple ways, for instance by capturing only from the largest CO2 sources at individual multi-stack sites utilising cheap waste heat or adapting the capture volumes to seasonal changes in operations. The main focus of this research is to perform techno-economic analyses for multiple partial CO2 capture concepts in order to identify economic optimums between cost and volumes captured. In total for four different case studies are developed for cement, iron & steel, pulp & paper and ferroalloys industries. The first part of the webinar gave an overview of the project with insights into the cost estimation method used. The second part presented the iron & steel industry case study based on the Lulea site in Sweden, for which waste-heat mapping methodology has been used to assess the potential for partial capture via MEA-absorption. Capture costs for different CO2 sources were discussed, demonstrating the viability of partial capture in an integrated steelworks.
|
|
| 15. |
- Goto, Yutaka, 1984, et al.
(författare)
-
Economic, ecological and thermo-hygric optimization of a vapor-open envelope for subtropical climates
- 2012
-
Ingår i: Energy and Buildings. - : Elsevier BV. - 0378-7788. ; 55:December 2012, s. 799-809
-
Tidskriftsartikel (refereegranskat)abstract
- With regard to resource depletion and global climate change, it is becoming important to take holistic measures comprising ecological, economic and social aspects of the construction industry. An optimization method that deals with the trade-off among those pillars is needed to approach the overall life span of constructions from a holistic viewpoint. In this study, the insulation thickness of a vapor-open envelope system for subtropical regions with social advantages was investigated by an economic and ecological optimization model, taking into account both initial and running costs under the conditions of 8 cities in Japan. The thermo-hygric minimum thickness was also determined in order to ensure the longevity of the buildings. The following main findings were made: (1) the ecological optimal thickness was larger than the economic optimal thickness, (2) the thermo-hygric minimum was within the economic optimal range in most of the cases, and (3) the interest rate of the currency and the electricity price increase have a significant influence on the result of the optimization analysis. With the aid of the optimization model, it was shown that application of the envelope system is feasible in Japan, especially in the central and southern regions.
|
|
| 16. |
- Jebrane, Mohamed, et al.
(författare)
-
Dimensional stability and mechanical properties of exoxidized vegetable oils as wood preservatives
- 2016
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In recent years, some vegetable oils such as linseed oil and soybean oil, have been used to preserve wood material, and contain no environmentally hazardous chemicals or chemicals harmful to humans. However, based on early studies related to vegetable oils, it was found that vegetable oils do not chemically bond with the wood structure, but rather only fill the cavities in the wood structure. This acts only to prevent the water uptake into wood. Because vegetable oils only act as a barrier to prevent water absorption, higher oil retentions (400 kg/m3 - 600 kg/m3) which are not cost-effective, would be needed to be effective in protecting wood. In this study, to reactivate oil and improve the bonding ability between oil and wood components, epoxidation of vegetable oil was targeted. Thus, more cost-effective oil retention levels between 80 kg/m3 and 270 kg/m3 were used due to treat the wood. With epoxidized vegetable oils, oil acids are able to bond to sites normally occupied by water molecules. This study also aimed to reduce leaching of boron compounds.
|
|
| 17. |
|
|
| 18. |
- Larsson, Sylvia, et al.
(författare)
-
Effects of moisture content, torrefaction temperature, and die temperature in pilot scale pelletizing of torrefied Norway spruce
- 2013
-
Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 102, s. 827-832
-
Tidskriftsartikel (refereegranskat)abstract
- Pilot scale pelletizing of torrefied Norway spruce was performed in a factorial design with controlled factors at two levels: material moisture content (11% and 15%) and torrefaction temperature (270 and 300 °C), and die temperature as an uncontrolled factor (60–105 °C). Compared to commercial wood pellets, produced pellets had comparable bulk densities (630–710 kg/m3) but lower pellet durability (80–90%). Energy consumption for pelletizing of torrefied materials was approximately 100% higher than for softwood pelletizing, despite using a much shorter die channel length (35 vs. 55 mm:s), and the amounts of fines were high (10–30%). Die temperature showed a strong positive correlation with pellet production rate. Material moisture content had little influence on pellet quality and production rate, but addition of water created handling problems due to bad flow behavior.
|
|
| 19. |
- Lundh, Torbjörn, 1965, et al.
(författare)
-
A Compression Garment for Provision of an Adjustable Pressure
- 2018
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- A compression garment for providing an adjustable pressure towards a body part is disclosed. The compression garment comprises a unitary single sheet of elastic material arranged to encircle the full circumference of a body part, such as a limb or the head. The sheet is folded or arranged to be folded in at least one predefined way, so that the folding forms one or more defined overlap(s) forming at least two overlaying layers of the sheet encircling the full circumference of a part of the body part. Hereby, the pressure profile of the garment can easily be adjusted by making use of the garment in different folded configurations. Markings may further be provided to provide guidance towards the predefined ways of folding.
|
|
| 20. |
- Mattsson, Tuve, 1979, et al.
(författare)
-
The use of fluid dynamic gauging in investigating the thickness and cohesive strength of cake fouling layers formed during cross-flow microfiltration
- 2018
-
Ingår i: Separation and Purification Technology. - : Elsevier BV. - 1873-3794 .- 1383-5866. ; 198, s. 25-30
-
Tidskriftsartikel (refereegranskat)abstract
- A common challenge during membrane filtration is cake fouling, whereby the build-up of material on the membrane surface reduces the permeate flux. Such fouling layers can also alter the selectivity of the separation. In this study, fluid dynamic gauging (FDG) is used in situ to investigate the cake fouling formed during cross-flow filtration of a model material: softwood Kraft lignin. FDG was used to estimate (i) the thickness of the cake layers (in the gm scale) and (ii) the local cohesive strength at different depths in the cake layer. Fouling layers formed at different transmembrane pressure (TMP) values were investigated. The estimated thickness of the cake layers increased with increasing TMP. However, it was difficult to capture the full cake thickness for the more loosely formed cakes layers. An increase in the cohesive strength of the cake was found to occur with increasing TMP values. (C) 2017 Elsevier B.V. All rights reserved.
|
|
