265 research outputs found

    The environmental benefits and challenges of a composite car with structural battery materials

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    One way to reduce the environmental impact of an electric vehicle is to reduce the vehicle’s mass. This can be done by substitution of conventional materials such as steel, aluminium, and plastics with carbon fibre composites, or possibly even with structural battery composite materials. In the latter case, another consequence is that the size of the vehicle battery is reduced as the structural battery composite not only provides structural integrity, but also stores energy. This study assesses the change in life cycle environmental impacts related to transitioning from a conventional battery electric vehicle to a vehicle with components made from either carbon fibre composites or structural battery composites, with the aim of identifying environmental challenges and opportunities for cars with a high share of composite materials. Results show that a transition to carbon fibre composites and structural battery composite materials today would (in most cases) increase the total environmental impact due to the energy intensive materials production processes. The two major contributors to the environmental impacts for the structural battery composite materials are energy intensive structural battery material manufacturing process and carbon fibre production process, both of which can be expected to decrease their energy consumption as the technology maturity level increases and other production and manufacturing processes are developed. For future assessments, more effort needs to be put on collecting primary data for large-scale structural battery composites production and on assessing different technology development routes

    Lusetellingsmetoder i lakseoppdrett - en beskrivelse av dagens status

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    Denne rapporten inngår i prosjektet "Utvikling av standardisert tellemetodikk og beregning av luseforekomst". Beskrivelser av dagens lusetellingsmetoder i lakseoppdrett er basert på intervju med ansatte som jobber på oppdrettsanlegg og etablerte prosedyrer. Dette materialet diskuteres mot relevant litteratur. Dokumentasjonen av dagens metoder for lusetelling er gjort med mål om å identifisere variasjon, styrker og utfordringer knyttet til ulike faser av lusetellingsprosessen, både med hensyn til tekniske aspekter og menneskelige faktorer. Rapporten viser blant annet at det er variasjon både mellom og internt i selskap når det gjelder valg av utstyr og fremgangsmåte. Flere ansatte oppgir at det kan være utfordrende å skille mellom ulike arter og stadier under lusetellingen. Prosjekt 901411 er finansiert av Fiskeri- og havbruksnæringens forskningsfond i perioden høst 2017 til sommer 2018. Det ledes av Norsk Institutt for Naturforskning (NINA), og utføres i samarbeid med SINTEF Ocean og Veterinærinstituttet (VI).Fiskeri- og havbruksnæringens forskningsfondpublishedVersio

    Role of shelfbreak upwelling in the formation of a massive under-ice bloom in the Chukchi Sea

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    Author Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 105 (2014): 17-29, doi:10.1016/j.dsr2.2014.03.017.In the summer of 2011, an oceanographic survey carried out by the Impacts of Climate on EcoSystems and Chemistry of the Arctic Pacific Environment (ICESCAPE) program revealed the presence of a massive phytoplankton bloom under the ice near the shelfbreak in the central Chukchi Sea. For most of the month preceding the measurements there were relatively strong easterly winds, providing upwelling favorable conditions along the shelfbreak. Analysis of similar hydrographic data from summer 2002, in which there were no persistent easterly winds, found no evidence of upwelling near the shelfbreak. A two-dimensional ocean circulation model is used to show that sufficiently strong winds can result not only in upwelling of high nutrient water from offshore onto the shelf, but it can also transport the water out of the bottom boundary layer into the surface Ekman layer at the shelf edge. The extent of upwelling is determined by the degree of overlap between the surface Ekman layer and the bottom boundary layer on the outer shelf. Once in the Ekman layer, this high nutrient water is further transported to the surface through mechanical mixing driven by the surface stress. Two model tracers, a nutrient tracer and a chlorophyll tracer, reveal distributions very similar to that observed in the data. These results suggest that the biomass maximum near the shelfbreak during the massive bloom in summer 2011 resulted from an enhanced supply of nutrients upwelled from the halocline seaward of the shelf. The decade long trend in summertime surface winds suggest that easterly winds in this region are increasing in strength and that such bloom events will become more common.This study was supported by the National Science Foundation under Grant OCE-0959381 (MAS), and by the Ocean Biology and Biogeochemistry Program and the Cryosphere Science Program of the National Aeronautic and Space Administration under Award NNX10AF42G (RSP;KRA). GWKM was supported by the Natural Sciences and Engineering Research Council of Canada. ETB was supported by the U. S. Navy

    Productivity in the Barents Sea - Response to recent climate variability

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    The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea since the late 1990s are examined using remote sensing data, observations and a coupled physical-biological model. Field observations of mesozooplankton biomass, and chlorophyll a data from transects (different seasons) and large-scale surveys (autumn) were used for validation of the remote sensing products and modeling results. The validation showed that satellite data are well suited to study temporal and spatial dynamics of chlorophyll a in the Barents Sea and that the model is an essential tool for secondary production estimates. Temperature, open water area, chlorophyll a, and zooplankton biomass show large interannual variations in the Barents Sea. The climatic variability is strongest in the northern and eastern parts. The moderate increase in net primary production evident in this study is likely an ecosystem response to changes in climate during the same period. Increased open water area and duration of open water season, which are related to elevated temperatures, appear to be the key drivers of the changes in annual net primary production that has occurred in the northern and eastern areas of this ecosystem. The temporal and spatial variability in zooplankton biomass appears to be controlled largely by predation pressure. In the southeastern Barents Sea, statistically significant linkages were observed between chlorophyll a and zooplankton biomass, as well as between net primary production and fish biomass, indicating bottom-up trophic interactions in this region

    Integrated Electro-Optic Isolator on Thin Film Lithium Niobate

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    Optical isolator is an indispensable component of almost any optical system and is used to protect a laser from unwanted reflections for phase-stable coherent operation. The development of chip-scale optical systems, powered by semiconductor lasers integrated on the same chip, has resulted in a need for a fully integrated optical isolator. However, conventional approaches based on application of magneto-optic materials to break the reciprocity and provide required isolation have significant challenges in terms of material processing and insertion loss. As a result, many magnetic-free approaches have been explored, including acousto-optics, optical nonlinearity, and electro-optics. However, to date, the realization of an integrated isolator with low insertion loss, high isolation ratio, broad bandwidth, and low power consumption on a monolithic material platform is still absent. Here we realize non-reciprocal traveling-wave EO-based isolator on thin-film LN, enabling maximum optical isolation of 48 dB and an on-chip insertion loss of 0.5 dB using a single-frequency microwave drive at 21-dBm RF power. The isolation ratio is verified to be larger than 37 dB across a tunable optical wavelength range from 1510 to 1630 nm. We verify that our hybrid DFB laser - LN isolator module successfully protects the single-mode operation and the linewidth of the DFB laser from reflection. Our result is a significant step towards a practical high-performance optical isolator on chip

    Histone deacetylase 6 inhibition improves memory and reduces total tau levels in a mouse model of tau deposition

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    INTRODUCTION: Tau pathology is associated with a number of age-related neurodegenerative disorders. Few treatments have been demonstrated to diminish the impact of tau pathology in mouse models and none are yet effective in humans. Histone deacetylase 6 (HDAC6) is an enzyme that removes acetyl groups from cytoplasmic proteins, rather than nuclear histones. Its substrates include tubulin, heat shock protein 90 and cortactin. Tubastatin A is a selective inhibitor of HDAC6. Modification of tau pathology by specific inhibition of HDAC6 presents a potential therapeutic approach in tauopathy. METHODS: We treated rTg4510 mouse models of tau deposition and non-transgenic mice with tubastatin (25 mg/kg) or saline (0.9%) from 5 to 7 months of age. Cognitive behavior analysis, histology and biochemical analysis were applied to access the effect of tubastatin on memory, tau pathology and neurodegeneration (hippocampal volume). RESULTS: We present data showing that tubastatin restored memory function in rTg4510 mice and reversed a hyperactivity phenotype. We further found that tubastatin reduced the levels of total tau, both histologically and by western analysis. Reduction in total tau levels was positively correlated with memory improvement in these mice. However, there was no impact on phosphorylated forms of tau, either by histology or western analysis, nor was there an impact on silver positive inclusions histologically. CONCLUSION: Potential mechanisms by which HDAC6 inhibitors might benefit the rTg4510 mouse include stabilization of microtubules secondary to increased tubulin acetylation, increased degradation of tau secondary to increased acetylation of HSP90 or both. These data support the use of HDAC6 inhibitors as potential therapeutic agents against tau pathology

    A structural battery and its multifunctional performance

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    Engineering materials that can store electrical energy in structural load paths can revolutionize lightweight design across transport modes. Stiff and strong batteries that use solid-state electrolytes and resilient electrodes and separators are generally lacking. Herein, a structural battery composite with unprecedented multifunctional performance is demonstrated, featuring an energy density of 24 Wh kg-1 and an elastic modulus of 25 GPa and tensile strength exceeding 300 MPa. The structural battery is made from multifunctional constituents, where reinforcing carbon fibers (CFs) act as electrode and current collector. A structural electrolyte is used for load transfer and ion transport and a glass fiber fabric separates the CF electrode from an aluminum foil-supported lithium–iron–phosphate positive electrode. Equipped with these materials, lighter electrical cars, aircraft, and consumer goods can be pursued

    Comprehensive multimodality characterization of hemodynamically significant and non-significant coronary lesions using invasive and noninvasive measures

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    Background There is limited knowledge about morphological molecular-imaging-derived parameters to further characterize hemodynamically relevant coronary lesions. Objective The aim of this study was to describe and differentiate specific parameters between hemodynamically significant and non-significant coronary lesions using various invasive and non-invasive measures. Methods This clinical study analyzed patients with symptoms suggestive of coronary artery disease (CAD) who underwent native T1-weighted CMR and gadofosveset-enhanced CMR as well as invasive coronary angiography. OCT of the culprit vessel to determine the plaque type was performed in a subset of patients. Functional relevance of all lesions was examined using quantitative flow reserve (QFR-angiography). Hemodynamically significant lesions were defined as lesions with a QFR <0.8. Signal intensity (contrast-to-noise ratios; CNRs) on native T1-weighted CMR and gadofosveset-enhanced CMR was defined as a measure for intraplaque hemorrhage and endothelial permeability, respectively. Results Overall 29 coronary segments from 14 patients were examined. Segments containing lesions with a QFR 0.8; n = 19) (5.32 (4.47–7.02) vs. 2.42 (1.04–5.11); p = 0.042). No differences in signal enhancement were seen on native T1-weighted CMR (2.2 (0.68–6.75) vs. 2.09 (0.91–6.57), p = 0.412). 66.7% (4 out of 6) of all vulnerable plaque and 33.3% (2 out of 6) of all non-vulnerable plaque (fibroatheroma) as assessed by OCT were hemodynamically significant lesions. Conclusion The findings of this pilot study suggest that signal enhancement on albumin-binding probe-enhanced CMR but not on T1-weighted CMR is associated with hemodynamically relevant coronary lesion

    The British economy [March 1992]

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    The recession in non-oil GDP has continued for six quarters with the real value of output falling by just under 4% since the second quarter of 1990. The present recession is therefore the longest since the Second World War, although the fall is still not as rapid, or as deep, as in the 1979-81 recession where the decline in non-oil GDP from peak to trough occurred over five quarters and amounted to 6.2%. Considerable uncertainty exists over the course of demand over the next few months, with consumption unlikely to exhibit strong growth. The likely outturn for GDP growth during 1992 is for an increase of no more than 1%. Macroeconomic trends, earnings and productivity, and unemployment levels are also analysed
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