1,720,981 research outputs found
Solar distillation meets the real world: a review of solar stills purifying real wastewater and seawater
No full textSolar energy-driven evaporation-based freshwater production is one of the sustainable ways to purify contaminated/salty water. Recent advances in solar absorbers’ assemblies, design modifications, and integrations with heating sources improved the rate of freshwater productivity. However, the type of feed water affects the evaporation rate in a solar desalination system (SDS). Many studies used tap water with added contaminants to test the performance of a SDS and studied the water quality improvement. As a typical result, pH, total dissolved solids (TDS), and electrical conductivity (µS/cm) are reduced after solar evaporation. The performance of SDSs for real wastewaters are also important to understand, e.g., the reduction of high organic pollutants after solar evaporation. In this aspect, the main objective of the present work is to review solar distillation of real wastewaters and seawater by using SDSs. Further, the mechanism of a solar distiller with heat transfer principles, parameters affecting evaporation process, real wastewaters and seawaters purified in a solar distillation system, improvement of various parameters before and after solar evaporation, pathways of handling wastewaters, challenges, and future perspectives are discussed. Conclusively, SDSs are found to remove pollutants effectively after solar evaporation. The evaporation rate is relatively slower due to high concentration of pollutants that reduce vapor pressure. The COD removal of various real wastewaters, including sludge, kitchen, textile, palm oil, petroleum, water plant, and municipal wastewaters, was 98.13%, 97.85%, 96.84%, 96.71%, 87.99%, 86.99%, and 85.67%, respectively. The reduction rate of salt concentration in real seawater after evaporation in the solar distiller was 99.99%.11Nsciescopu
A review on efficiently integrated passive distillation systems for active solar steam evaporation
No full textSolar energy-driven desalination is one of sustainable means to produce reusable water. Recently, solar distiller formally known as a solar still (SS) has been commonly employed to get freshwater through evaporation and consequent condensation process. However, such passive systems are typically slow on the distillation process, because bulk heating requirement and other energy losses. To increase the fresh water productivity of the passive distillation systems, researchers have usually adopted concentrators, reflecting mirrors, evacuated tube collectors (ETC), energy absorbing-engineered nanoparticles and energy storage (sensible and latent heat) materials. In this manner, water in a distiller can obtain additional heat and speedy evaporation take place immediately. Thus, efficient integration of passive distillation is highly useful to achieve appreciable production rate of fresh water for human daily needs. In this aspect, many researchers continuously tried to develop new innovative technologies for effective solar desalination. The main objective of this assessment is to review the current integration strategies and consequences for improving the productivity of solar distillers. Here, the term integration comprises additional heat sources, including heat confinement to broadband nanoparticles (micro-integration), concentrators, reflecting-mirrors (macro-integration), latent heat storage (LHS), sensible heat storage (SHS), and wicking cloth-based absorbers. This review exclusively focused on the newest results in the year of 2020–2021. In addition, the challenges, limitations, and requirements for future prospects are discussed.11Nsciescopu
A review on carbonized natural green flora for solar desalination
No full textSolar desalination is one of the green energy processes to treat saline water and wastewater. Solar evaporation systems, formally solar stills, have been widely used to evaporate water to purify it. However, the evaporation rate in solar stills is typically low due to incoming energy used to heat the entire bulk water. In order to minimize the bulk heating, researchers have developed capillary flow-based, self-floatable, broadband photothermal absorbers (250–2500 nm wavelength) for fast solar evaporation. Recently, interfacial solar steam generation (ISSG) has attracted attention due to significant advantages in desalination and water treatment. In general, ISSG materials are classified into plasmonic metals, semiconductors, black carbon and polymer-based materials. The basic requirements for these photothermal materials include being self-floatable and having high solar absorption, fast water transport (capillary action) and low thermal conductivity to confine the heat locally. Some natural plant species satisfy these prerequisites and have been used as photothermal materials in solar steam generation (SSG). The present review exclusively focuses on the carbonized botanical species, including bamboo, corncob, corn-stalk, coconut-husk, carrot, fruit residues (cherry, grape, orange and apple), green algae, loofah fruit, magnolia fruit, mushroom, lotus leaf and seedpods, sugarcane, sunflower head, tofu, wheat flour and wood pieces for improving the evaporation rate and efficiency. Carbonization technique improves the solar absorption by increasing the carbon concentration. In addition, these floatable solar absorbers evaporate the water with the aid of natural microchannels. These materials not only improve the efficiency, but also have economic and environmental benefits.11Nsciescopu
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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