60 research outputs found
Deadlock-free incremental replay of message-passing programs
No full textTo support incremental replay of message-passing applications. processes must periodically checkpoint and the content of some messages must be logged, to break dependencies of the current slate of the execution on past events. This paper shows that known adaptive logging algorithms are likely to introduce deadlocks in replay, and we introduce a new algorithm that: (i) prevents deadlocks in replay and (ii) enables the tuning of its behavior to meet specific user needs
Making decisions about benefits and harms of medicines
No full textEven when good scientific data are available, people’s interpretation of risks and benefits will differ
A bio-inspired and switchable H<sup>+</sup>/OH<sup>−</sup> ion-channel for room temperature exhaled CO<sub>2</sub> chemiresistive sensing
No full textInspired by the CO2-induced reversible activation mechanism of the slow anion channel 1 (SLAC1) in plant stomatal guard cells during plant photosynthesis, we designed and prepared a CO2- switchable H+/OH− ion channel (CSPH ion channel). A high-performance chemiresistive room temperature CO2 sensor has been prepared based on this CSPH ion channel. The obtained CO2 room temperature sensor γ-CD-MOF@RhB exhibits high sensitivity (Rg/R0 = 1.50, 100 ppm), excellent selectivity, good stability (less than 5% reduction in 30 days response value), and 99.96% consistency with commercial infrared CO2 meter. The practical limit of detection (pLOD) of the γ-CD-MOF@RhB sensor reaches 10 ppm at room temperature toward CO2, which is the lowest for reported MOF-derived chemiresistive room temperature CO2 sensors so far. Ion conduction mechanism studies have shown that the CSPH ion channel behaves as a CO2-switchable H+/OH− ion channel with a switching point of approximately 60 000 ppm CO2. As an application attempt, the fabricated low pLOD CO2 sensor has been used for human exhaled CO2 detection to compare CO2 concentration in the breath of individuals before and after exercise and COVID-19. It was also logically indicated that the average concentration of human exhaled CO2 after COVID-19 recovery is different for undiseased subjects.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Bio-Electronic
Synthesis and characterisation of nanostructured BiFeO3 for photodecolourisation of azo dyes using visible light
Get PDFIn this work, effort is being made to synthesize a narrow band gap ferroelectric perovskite nanostructure semiconductor that is BiFeO3 (BFO). The BFO nanopowders were synthesized at 650ºC using a self-combustion method with glycine as the fuel. The effect of the different fuel concentrations, annealing temperatures and the duration of annealing are all demonstrated to influence the phase and crystallography of the synthesized nanoparticles. The author has demonstrated that the self-combustion process can be used to produce high purity BFO nanopowders which exhibit good absorption in the visible-light regime as determined by the UV-Vis-NIR spectroscopy with a measured optical band gap of 2.22 eV. Cont/d
A facile hydrothermal approach to synthesize rGO/BiVO4 photocatalysts for visible light induced degradation of RhB dye
No full textSustainability assessment in residential high-rise building design: state of the art
Get PDFThis is an Accepted Manuscript of an article published by Taylor & Francis Group in Architectural Engineering and Design Management on 2022, available online at: http://www.tandfonline.com/10.1080/17452007.2022.2060931.Twenty-first-century population growth is raising the need for more land space in urban areas and this has led to the construction of high-rise buildings, reducing horizontal urban development and making construction of residential high-rise buildings (RHB) a necessity in major cities around the world. In this regard, urban density and high-rise construction are key factors when determining a city’s sustainability and the liveability of urban areas. Sustainability indicators were identified in previous research and quantification has proven to be a useful tool for RHB design. This paper provides an overview of the various sustainability factors applied to RHB design. The paper also compiles information on the sustainability strategy, description of RHB issues and how this type of building can affect urban design. Some strategies may improve the natural environment such as incorporating green spaces, combining living, working and leisure activities, providing facilities for children and the elderly such as playgrounds and reasonably natural settings, ease of access to public transport, road networks and shopping facilities and so forth. The research is based on a descriptive approach and it analyses previous studies. The findings show that the environmental, economic and social aspects of sustainable development (SD) should be considered to implement sustainability in RHBs. Previous literature reviews on RHBs considered social aspects in less detail.The author Maria del Mar Casanovas-Rubio is a Serra Húnter Fellow. The author Bahareh Maleki would like to thank the FPI-UPC grantsPeer ReviewedPostprint (author's final draft
Enhanced photocatalytic performance of g-C3N4 nanosheets-BiOBr hybrids
No full textExfoliated g-C3N4 (CNs)-BiOBr hybrids with heterojunction structure was fabricated through a chemical deposition precipitation route. The characterization showed the uniform existence of CNs and BiOBr in hybrids. The fabricated CNs-BiOBr was of enlarged specific surface area, unique optical property, and well-matched energy-band structures. The photocatalytic performance on dye Rhodamine B (RhB) and 2,4-diclorophenol (2,4-DCP) were dramatically improved. Under identical conditions, sample 0.5CNs-BiOBr and CNs BiOBr were identified as the best candidate, respectively, for catalytic degradation of RhB and 2,4-DCP. The former could show a reaction rate over RhB about 2.7 and 6.8 times as high as BiOBr and CNs alone, and the later exhibited a reaction rate over 2,4-DCP nearly 7.5 and 2.5 times as high as individual BiOBr and CNs. Finally, a possible catalytic mechanism was also proposed through active species trapping experiments. (C) 2014 Elsevier Ltd. All rights reserved.Exfoliated g-C3N4 (CNs)-BiOBr hybrids with heterojunction structure was fabricated through a chemical deposition precipitation route. The characterization showed the uniform existence of CNs and BiOBr in hybrids. The fabricated CNs-BiOBr was of enlarged specific surface area, unique optical property, and well-matched energy-band structures. The photocatalytic performance on dye Rhodamine B (RhB) and 2,4-diclorophenol (2,4-DCP) were dramatically improved. Under identical conditions, sample 0.5CNs-BiOBr and CNs BiOBr were identified as the best candidate, respectively, for catalytic degradation of RhB and 2,4-DCP. The former could show a reaction rate over RhB about 2.7 and 6.8 times as high as BiOBr and CNs alone, and the later exhibited a reaction rate over 2,4-DCP nearly 7.5 and 2.5 times as high as individual BiOBr and CNs. Finally, a possible catalytic mechanism was also proposed through active species trapping experiments. (C) 2014 Elsevier Ltd. All rights reserved
Variation of the characteristics of deltaic and stream bed deposits in laboratory studies
Get PDFCER 67-68TAR-RHB-DBS34.1967.Includes bibliographical references (page 15).This paper discusses the major processes that influence the distribution and characteristics of sedimentary deposits in deltaic systems (stream channel and delta). The distributions of the sediment sizes in the sedimentary deposits in several laboratory deltaic systems formed under steady-state conditions were determined. Statistical moments of the sediment size distribution were calculated and some explanations of their characteristics are given. Two size ranges of cohesionless sediments were use, along with several water discharges. The laboratory deltas were characterized by the classical top-, fore-, and bottom-set beds. Two- and three-dimensional deltas were analyzed and the relationships between the two are discussed. This paper should be of particular interest to the hydrologist, hydraulic engineer and sedimentologist whose interests include flow conditions that can be associated with a sedimentary deposit, rate of depositions in reservoirs, water resources development and sediment yield from rivers and river systems
The promoted photoelectrocatalytic degradation of rhodamine B over TiO2 thin film under the half-wave pulsed direct current
No full textThe photoelectrocatalytic (PEC) degradation of rhodamine B(RhB) over nanosized titanium dioxide (TiO2) coated working electrode was investigated under the half-wave pulsed direct current (DC). It was found that the PEC degradation of RhB was greatly enhanced under the half-wave pulsed DC mode, compared to under the constant DC mode widely used in the photoelectrochemical cells. It was mostly ascribed to it that the electrons could be more efficiently conducted into the outer circuit under the half-wave pulsed DC, leading to the improved generation of the holes at the surface of TiO2 working electrode and thereby promoting the PEC oxidation of RhB, relative to under the constant DC. We provide a simple and promising way to improve the photocatalytic oxidation of organic dyes over TiO2 thin film. (C) 2010 Elsevier By. All rights reserved.Chemistry, PhysicalEngineering, EnvironmentalEngineering, ChemicalSCI(E)EI15ARTICLE3-4464-46910
Evaluation of rice husk biochar influence as a partial cement replacement material on the physical, mechanical, microstructural, and radiation shielding properties of ordinary concrete
No full textThis study investigated the viability of rice husk-derived biochar (RHB) as a partial substitute for cement in concrete. The used RHB, characterized by a novel chemical composition abundant in silicon and aluminum oxides, was incorporated into ordinary concrete at increasing substitution ratios up to 25% by cement weight. A comprehensive evaluation was conducted to assess the influence of RHB on various properties of concrete, including physical (setting time, standard consistency, workability), mechanical (compressive and tensile strength), microstructural (XRD, and EDX), and radiation shielding characteristics. The results indicated that RHB marginally increased cement setting time, with a maximum 7.14% increase observed at a 25% replacement level. However, it significantly increased water demand for standard consistency, reaching 35.7% at 25% replacement. The increased water demand correlated with a reduction in workability, with a maximum slump reduction rate of 57.3% at a 25% replacement level. The optimal replacement levels for mechanical strength enhancement were at 10% for compressive strength and 15% for tensile strength, achieving improvements of 13.74% and 9.48%, respectively. Additionally, Monte Carlo simulation code and PhyX software were employed for assessing gamma and fast neutron radiation attenuation characteristics of concrete. Gamma-ray attenuation tests revealed moderate improvements in the concrete's gamma-ray shielding capacity. Interestingly, the 15% RHB sample demonstrated a higher linear attenuation compared to the other samples, a result of its increased density. On the contrary, the 25RHB sample is less valuable. The 15RHB sample had the highest value for FCS (0.090 cm ) indicating its efficacy as a neutron shield. [Abstract copyright: © 2025. The Author(s).
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