1,721,034 research outputs found
Comparative Building Energy Simulation Study of Static and Thermochromically Adaptive Energy-Efficient Glazing in Various Climate Regions
No full textThe building sector contributes approximately one third of the total energy consumption worldwide. A large part of this energy is used for the heating and cooling of buildings, which can be drastically reduced by use of energy-efficient glazing. In this study, we performed building energy simulations on a prototypical residential building, and compared commercially available static (low-e, solar IR blocking) to newly developed adaptive thermochromic glazing systems for various climate regions. The modeling results show that static energy-efficient glazing is mainly optimized for either hot climates, where low solar heat gain can reduce cooling demands drastically, or cold climates, where low-e properties have a huge influence on heating demands. For intermediate climates, we demonstrate that adaptive thermochromic glazing in combination with a low-e coating is perfectly suited. The newly developed thermochromic glazing can lead to annual energy consumption improvement of up to 22% in comparison to clear glass, which exceeds all other glazing systems. Furthermore, we demonstrate that in the Netherlands the use of this new glazing system can lead to annual cost savings of EU 638 per dwelling (172 m2, 25% window façade), and to annual nationwide CO2 savings of 4.5 Mt. Ergo, we show that further development of thermochromic smart windows into market-ready products can have a huge economic, ecological and societal impact on all intermediate climate region in the northern hemisphere
Low Temperature Sunlight-Powered Reduction of CO<sub>2</sub> to CO Using a Plasmonic Au/TiO<sub>2</sub> Nanocatalyst
Full text linkSunlight-powered reduction of CO2 to fuels and chemicals is a promising strategy to close the carbon loop and facilitate the energy transition. In this research, we demonstrate that Au nanoparticles supported on TiO2 are an efficient plasmonic catalyst for the sunlight-powered reverse water-gas shift (rWGS) reaction. A maximum CO production rate of 429 mmol ⋅ gAu−1 ⋅ h−1 with a selectivity of 98 % and an apparent quantum efficiency of 4.7 % were achieved using mildly concentrated sunlight (1.44 W ⋅ cm−2 equals 14.4 sun). The CO production rate showed an exponential increase with increasing light intensity, suggesting that the process is mainly promoted by a photothermal effect. Thermal reference experiments with the same catalysts promoted CH4 formation, dropping the CO selectivity to 70 %. Thus, mildly concentrated sunlight can efficiently and selectively enhance the promotion of the rWGS reaction without using external heating.ImPhys/Optic
Renewable natural gas as climate-neutral energy carrier?
Full text linkNatural gas is a potent greenhouse gas but remains an attractive energy resource for a good number of reasons. Because complementing the use of natural gas with carbon dioxide capture and storage yields several drawbacks, producing synthetic natural gas instead could be an interesting alternative. Methanation is an established and well-known process, and with atmospheric carbon dioxide as input it could deliver a climate-neutral energy carrier, which we refer to as renewable natural gas. At present, however, methanation is exceedingly costly. In this paper we try to answer two main questions: (I) can innovative methanation such as based on sunlight-powered plasmon catalysis compete with more conventional methanation options using the Sabatier reaction in e.g. adiabatic fixed-bed processes; (II) can these two alternatives ever compete with abundantly available natural gas? Under realistic assumptions for technology learning, we find that innovative methanation technology could compete with conventional methanation systems sometime between 2032 and 2039 in our base case scenario. The required learning investments for the innovative option would amount to about 80 M€, spent on an installed capacity of around 750 MW. We also conclude that the levelized cost of methane remains dominated by the cost of hydrogen until at least the middle of the century. Methanation could in principle compete with natural gas by 2050, but only if a carbon tax is levied of at least 270 €/tCO2.</p
Plasmon-assisted photocatalytic conversion of carbon dioxide -a demonstration by two case studies
No full textPlasmon-assisted photocatalytic conversion of carbon dioxide – a demonstration by two case studies
No full textThis work received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 101015960 (SPOTLIGHT).
This work received financial support from the VLAIO network through the Catalisti Moonshot project D2M
Plasmon-assisted photocatalytic conversion of carbon dioxide – a demonstration by two case studies
No full textThis work received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement 101015960 (SPOTLIGHT).
This work received financial support from the VLAIO network through the Catalisti Moonshot project D2M
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
