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A biofluid-repellent nanograss coating enhances flow of protein solutions and preserves transparency of glass capillaries upon exposure to blood
No full textA transparent and superhydrophobic (SHB) nanograss coating makes glass capillaries repellent toward protein solutions and blood. The coating is fabricated using atomic layer deposited alumina which is converted into grass-like alumina (GLA) by hot water treatment (HWT). The resulting tubes are transparent and highly repellent towards water and protein solutions (sliding angle <6° for a concentrated albumin solution). The biofluid repellence of the coating reduces hydraulic resistances for protein-rich biofluids, including fetal bovine serum, by 0–50% with the strongest effect for the smallest tubes and lowest Reynolds numbers. This work addresses a knowledge gap where previous studies have mostly focused on pure water for the drag reduction effect. The tubes also show a promising ability to stay clean and transparent on short term exposure to blood, unlike unmodified glass or polymer controls
Extraction of brominated flame retardants from acrylonitrile butadiene styrene (ABS) using supercritical carbon dioxide
Get PDFElectrical and electronic equipment, as well as construction materials, commonly contain brominated flame retardants (BFRs), which are harmful to human health and the environment. These additives can cause major issues during disposal or recycling phases and, hence, methods to remove them are highly demanded. This study focuses on removing three BFRs, namely Tetrabromobisphenol A (TBBPA), Decabromodiphenyl Ether (decaBDE), and Hexabromocyclododecane (HBCD) from acrylonitrile butadiene styrene (ABS) plastic using supercritical carbon dioxide (scCO2) extraction. Virgin ABS compounds with known BFR concentrations were prepared by melt extrusion and injection moulding, and the scCO2 extraction parameters, including extractor configuration, extraction time, pressure, temperature, type of co-solvents and physical dimensions of the sample, were optimized. To further remove the BFRs, samples were then cleaned in a pressure extractor with isopropanol (hybrid approach), achieving high BFR removal efficiency. The elemental bromine and BFR concentrations in the samples, both before and after the scCO2 extraction, were examined by X-ray fluorescence (XRF) analysis and mass spectrometry, respectively. In a semi-continuous configuration for the scCO2 extractor at 100 °C and ethanol co-solvent we effectively removed all three BFRs achieving a maximum bromine extraction of 84.3% from ABS-TBBPA samples during 240 min. In the hybrid approach, the extraction increased to 89.4% by treating the samples in the pressure extractor
Implication of building renovation and renewable integration on the energy resilience in the Nordic climate: Techno-economic analysis using questionnaire-based thresholds
Get PDFAs climate change worsens energy insecurity, resilience to long-term blackouts in cold climates is increasingly critical. Blackouts can compromise indoor heating, leading to serious habitability, health, and survivability risks. Yet, most existing regulatory frameworks lack clear definitions of minimum habitability and survivability thresholds, and often under examine the role of demographic and social factors. This study presents a novel, integrated, human-centric method that combines a single-stage occupants survey—designed to assess energy resilience awareness, occupant-defined habitability and survivability thresholds, and key demographic factors—with a detailed building performance simulation model. Survey data was collected from 378 participants residing in a cold climate region (Finland) and is integrated with simulations of both old and renovated residential buildings, incorporating various passive and active energy systems, including building envelope, photovoltaics (PV), battery storage, and heat pumps. This interdisciplinary approach enables a comprehensive techno-economic analysis that effectively bridges social perceptions with technical assessments of energy resilience. Moreover, a new set of energy resilience indicators is proposed, specifically tailored for buildings in cold regions. These indicators form the basis of a color-based classification scheme used to visualize simulation outcomes and compare the resilience performances of the buildings. Survey results show that heating (i.e., habitability) is the top need in Finland, followed by electrical loads (i.e., survivability). Habitability thresholds differ by age, gender, location, and building type, ranging from 15 °C to 19 °C. Older buildings fail to meet these needs, especially for people over 50 years old. In passive conditions, dissatisfaction among older adults reaches 100 % and elevated psychological stress values. Renovations and renewable energy systems greatly improve resilience, reducing low heating risks and physiological stress—though at a 94 % cost increase. Dissatisfaction with habitability drops from 100 % to 1 %, and survivability improves from 0 % to 98 %. For adults aged 41–61+, dissatisfaction drops to 90 % (men) and 98 % (women) with building renovation, and with PV-battery systems, it falls to 0 % for both. This research offers a transferable, occupant-centered framework for assessing energy resilience, bridging technical, social, and economic dimensions to guide building adaptation in other cold climates and Nordic countries
Degrowth and postgrowth:A systematic literature review of growth-critical science
No full textThis article is a systematic review of the bourgeoning field of studies employing growth-critical concepts, namely degrowth and postgrowth. First, it demonstrates how these concepts are used across disciplines, and how they consequently have varying approaches to theory, subject matter, and policy. Secondly, it maps the topography of growth-critical science to demonstrate the topical differences and similarities in these studies. By topic modelling, a natural-language processing machine-learning method, the study finds 20 focal topics from 943 articles. The critiques of growth appear in various combinations, allowing the article to compile the main topics and to demonstrate how they span across studies. The article challenges the assumption that growth-critical science forms a united political or scholarly agenda beyond being critical towards perpetual economic growth.<br/
Flexible Cu2AgBiI6-based perovskite-inspired solar cells using large-scale processing methods
Get PDFIn this work, emerging perovskite-inspired Cu2AgBiI6 (CABI) solar cells were successfully fabricated on flexible substrates, demonstrating that the transition from rigid to flexible materials does not compromise device performance. This underscores the versatility of CABI on two different kinds of substrates. Additionally, to optimize charge extraction, we selected a polymeric hole-transport material (HTM), PPDT2FBT, whose energy levels align with CABI. The PPDT2FBT-based devices outperformed those using the well-known poly(3-hexylthiophene) (P3HT), leading to power conversion efficiencies as high as approximately 0.8%. These results suggest that PPDT2FBT may hold promise as a HTM for use in low-toxicity, perovskite-inspired photovoltaic systems, such as those based on CABI. Furthermore, roll-to-roll processing techniques, crucial for scalable production, were tested. However, controlling the morphology of the active layer remains a significant challenge. These findings represent critical steps toward the large-scale manufacturing and commercialization of flexible, PIM-based solar cells
Semi-quantitative Lateral Flow Assay Using a Handheld Device with a Transmissive Readout
Get PDFLateral flow assays (LFAs) are widely used for rapid and cost-effective diagnostic testing. The assays are often qualitative relying on a binary interpretation of the results on test strips. In many applications, however, quantitative or semi-quantitative readout is needed to define the analyte molecule concentration in a sample matrix, such as, saliva or urine. This study focuses on developing a semi-quantitative LFA test concept with a customized test strip cartridge and transmissive optical detection. LFA was developed to detect Covid-19 proteins and the coloration of the test line was induced by the concentration of plasmonic nanoparticles. Spectroscopic characterization of the test strips showed that the signal strength was enhanced by 82% on average when the conventional reflection-based detection was substituted by a transmission detection. When a set of LFA tests were read with the developed handheld optoelectronic device, the observed standard deviation was found to be below 3% meeting the requirements for semi-quantitative analyses.</p
Flexible Cu2AgBiI6-based perovskite-inspired solar cells using large-scale processing methods
Get PDFIn this work, emerging perovskite-inspired Cu2AgBiI6 (CABI) solar cells were successfully fabricated on flexible substrates, demonstrating that the transition from rigid to flexible materials does not compromise device performance. This underscores the versatility of CABI on two different kinds of substrates. Additionally, to optimize charge extraction, we selected a polymeric hole-transport material (HTM), PPDT2FBT, whose energy levels align with CABI. The PPDT2FBT-based devices outperformed those using the well-known poly(3-hexylthiophene) (P3HT), leading to power conversion efficiencies as high as approximately 0.8%. These results suggest that PPDT2FBT may hold promise as a HTM for use in low-toxicity, perovskite-inspired photovoltaic systems, such as those based on CABI. Furthermore, roll-to-roll processing techniques, crucial for scalable production, were tested. However, controlling the morphology of the active layer remains a significant challenge. These findings represent critical steps toward the large-scale manufacturing and commercialization of flexible, PIM-based solar cells
Deep learning for green energy: predicting consumption and production trends across the Americas
Get PDFGreen energy projections can help meet rising energy needs, address climate change, and other challenges by forecasting future trends. This study uses data from 1965 to 2023 to predict American green energy production and consumption. The gated recurrent unit model was chosen because it shows the time-dependent structure in the data time series. This study utilized energy consumption and renewable generation sources from Kaggle, spanning from 1965 to 2022, and data from the Energy Institute website, covering the period from 2022 to 2023. The model has a mean absolute error of 0.0417 and 0.0341 for consumption and production, respectively, and a mean squared error of 0.0110 and 0.0083 for production. The GRU model achieves the highest accuracy, identifying green energy data trends with an RMSE of 0.1049 for consumption and 0.0912 for output. This study shows how this model predicts energy needs. It emphasizes the integration of renewable energy and innovation in resource distribution. The research says the Quest for More Sustainable energy systems must overcome predicted technical challenges. All stakeholders gain from improved energy management policies with this knowledge. The GRU model’s performance enables the incorporation of economic and meteorological data to enhance prediction accuracy and support global efforts to clean up the energy system
Degrowth and postgrowth:A systematic literature review of growth-critical science
No full textThis article is a systematic review of the bourgeoning field of studies employing growth-critical concepts, namely degrowth and postgrowth. First, it demonstrates how these concepts are used across disciplines, and how they consequently have varying approaches to theory, subject matter, and policy. Secondly, it maps the topography of growth-critical science to demonstrate the topical differences and similarities in these studies. By topic modelling, a natural-language processing machine-learning method, the study finds 20 focal topics from 943 articles. The critiques of growth appear in various combinations, allowing the article to compile the main topics and to demonstrate how they span across studies. The article challenges the assumption that growth-critical science forms a united political or scholarly agenda beyond being critical towards perpetual economic growth.<br/
Towards Real-Time Design Collaboration:LiveCol Final Report
Get PDFLiveCol set out to develop and validate methods and tools that enable realtime,data-driven collaboration in construction design. The project aimedto move from differentiated, semi-coordinated workflows toward parallel,open, and up-to-date information management supported by 3D tools andintegrated communication services