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These 285 documents have been used for the three sections that are part of the results of this article (documents statistics, bibliometric analysis, and literature review statistics). For this purpose, it was necessary to carry out an exhaustive review of the 285 selected documents and to complement this information with the data provided by Scopus. The data-charting process was as follows: the four researchers agreed on the types of data to be extracted, two of them carried out the review while the other two supervised. If any type of data worthy of investigation emerged during the reading, it was discussed, and if appropriate, included, making it an iterative process. For each of the documents, the following variables were collected in a table: author/s, title of the document, year of publication, journal in which it was published, type of document (article or review), number of citations and citations per year, relevance (weighting given by Scopus), DOI, geographical location of researchers, abstract, author keywords and keywords suggested by Scopus, JIF, JCI and H-index information of the journal in which the document is published (with quartiles and percentiles), subject area categories provided by Scopus, territory studied, renewable energy source studied, research technique or methodology used, primary data source used and years collected. In addition, for articles using quantitative techniques, all variables included in each model have been collected.

Abstract With drastic fossil fuel depletion and environmental deterioration concerns, a move towards a more sustainable bioenergy-based economy is essential. Lately, the application of microwave (MW) irradiation for waste processing has been attracting interest globally. MW-assisted heating possesses several advantages such as the provision of high microwave energy into dielectric materials with deeper penetration for internal heat generation, showing beneficial features in improving the heating rate and reducing the reaction time. Consequently, the most recent literature regarding the applications of MW-assisted heating for biomass pretreatment as well as biofuel and bioenergy production was reviewed and consolidated in this study. An impressive increase in the product yield and improvement of the product properties are reported, with the use of MW-assisted heating in several conversion routes to produce biofuels. Despite being a promising technology for biofuel production, some major fundamental data of MW-assisted heating have not been comprehensively identified. Therefore, the feasibility of this technology for large-scale implementation is still subpar. Understanding the interaction between the feedstock and the microwave electromagnetic field, and the optimization of several operational and mechanical parameters are the two main keystones that would propel the industrialization of MW heating in the near future. This provides key insights leading to increased feasibility and more advanced application of MW heating.

The phenomenon of global change is prompting the implementation of measures aimed at mitigating various effects, with humans being primarily impacted. The objective of this investigation is to analyse the potential self-sufficiency in the built environment through the utilisation of energy generated by photovoltaic systems. These systems have the capacity to reduce or even eliminate the reliance on grid electricity and non-renewable energy sources. The study commences with the delineation of eight neighbourhoods within the city of Madrid, Spain, each characterised by a distinct building typology. In order to ascertain the degree of self-sufficiency, this study calculates the energy production from solar photovoltaic systems installed on rooftops, and then proceeds to assess the energy consumption of each building. The results of the analysis demonstrate the capacity of photovoltaic installations to meet the electricity demands of buildings, such as single-family houses, almost completely, and partially in others, such as multi-family dwellings with multiple units per floor. Furthermore, the impact of differences in building height and urban context on self-sufficiency potential is explored.

The use of bioethanol as a biofuel make it possible to reduce the dependence on fossil fuel and the greenhouse emissions. The advantage of bioethanol is that is obtained by fermentation of renewable resources that capture carbon dioxide during its growing providing a null net balance of carbon dioxide emissions. Applying the concept of green engineering led to total or partial substitution of fossil fuel. The main drawback is that fermentation is produced in diluted aqueous media and the recovery of ethanol is an energy intensive operation and in Europe, the maximum ethanol content in fuel allowed by legislation is 10% wt (Directive 2009/10/EC). The objective of this project is to provide a process scheme that led to dehydrate bioethanol and blend directly with gasoline and gasoline additive, tert-amyl-methyl ether (TAME). This process must to be viable in terms of energy, economics and environmental aspects. A bibliographic search is presented to determine how much energy is necessary to produce one kilogram of bioethanol. The results of the bibliographic search shown that for a diluted feed stream of ethanol, the best process scheme consist on two distillation columns and one decanter. Hence, five process schemes are presented: (1-3) with the conventional configuration (two distillation column and one decanter) and (4-5) with a novel configuration (one distillation column, with a lateral extraction, and one decanter). The residue curve maps and liquid-liquid equilibrium (RCM-LLE) with their topologies are presented. The RCM-LLE allows to illustrate the thermodynamic behavior of the entrainers used and verify the feasibility. The software used to carry out the rigorous simulations is ASPEN Plus ® v10 using the thermodynamically model NRTL. The annual production established is 18kt/year of a mixture ethanol-gasoline-TAME. The converged results of the simulations allow to compare all the process schemes in terms of energy, sizing and economic aspects, such as raw materials cost, utilities cost, equipment cost and income statement. Beyond this, WAR® is used to compare the environmental impact of each process scheme using coal, oil and natural gas as an energy source Treballs Finals de Màster d'Enginyeria Química, Facultat de Química, Universitat de Barcelona, Curs: 2018-2019, Tutors: Alexandra Bonet Ruiz, Manuel Vicente Buil

An amorphous WO3 induced lattice distortion strategy leads to only 2 wt% Ir for efficient overall water splitting in acid.

Abstract Wolfiporia cocos, a versatile fungus acclaimed for its nutritional and therapeutic benefits in Traditional Chinese Medicine, holds immense potential for pharmaceutical and industrial applications. In this study, we aimed to optimize liquid fermentation techniques and culture medium composition to maximize mycelial biomass (MB) yield, pachymic acid (PA) concentration, and overall PA production. Additionally, we investigated the molecular basis of our findings by quantifying the expression levels of genes associated with PA and MB biosynthesis using quantitative real-time polymerase chain reaction. Under the optimized fermentation conditions, significant results were achieved, with maximum MB reaching 6.68 g l−1, PA content peaking at 1.25 mg g−1, and a total PA yield of 4.76 g l−1. Notably, among the four examined genes, squalene monooxygenase, exhibited enhanced expression at 0.06 ratio under the optimized conditions. Furthermore, within the realm of carbohydrate-active enzymes, the glycoside hydrolases 16 family displayed elevated expression levels at 21 ratios, particularly during MB production. This study enhances understanding of genetic mechanism governing MB and PA production in W. cocos, highlighting the roles of squalene monooxygenase and glycoside hydrolases 16 carbohydrate-active enzymes.

El propòsit de la tesi va ser explorar mitjançant estudis empírics l'evolució de l'ús de les eines Lean a les empreses manufactureres europees i el seu vincle amb les tecnologies de la Indústria 4.0 i les pràctiques green. En primer lloc, es va investigar l'adopció i la internalització de les eines Lean i el seu impacte en el rendiment productiu a les empreses manufactureres espanyoles. Tot seguit, es va analitzar la influència de la internalització de les eines Lean en l'adopció de tecnologies de la Indústria 4.0 a les empreses manufactureres europees. I, finalment, es va examinar la relació entre l'ús conjunt d'eines Lean i les pràctiques green associat a l'exercici mediambiental a les empreses manufactureres espanyoles. La metodologia emprada al llarg dels estudis presentats es va basar en l'anàlisi de dades extretes de la European Manufacturing Survey The purpose of the thesis was to explore through empirical studies the evolution of the use of lean tools in European manufacturing firms and their link with Industry 4.0 technologies and green practices and Circular Economy. First, the adoption and internalisation of lean tools and their impact on production performance in Spanish manufacturing firms were investigated. Next, the influence of the internalisation of Lean tools on the adoption of Industry 4.0 technologies in European manufacturing firms was analysed. Finally, the relationship between the joint use of Lean tools and green practices associated with environmental performance in Spanish manufacturing firms was examined. The methodology employed throughout the studies presented was based on the analysis of data extracted from the European Manufacturing Survey Programa de Doctorat Interuniversitari en Dret, Economia i Empresa

AbstractMountain treelines are thought to be sensitive to climate change. However, how climate impacts mountain treelines is not yet fully understood as treelines may also be affected by other human activities. Here, we focus on “closed‐loop” mountain treelines (CLMT) that completely encircle a mountain and are less likely to have been influenced by human land‐use change. We detect a total length of ~916,425 km of CLMT across 243 mountain ranges globally and reveal a bimodal latitudinal distribution of treeline elevations with higher treeline elevations occurring at greater distances from the coast. Spatially, we find that temperature is the main climatic driver of treeline elevation in boreal and tropical regions, whereas precipitation drives CLMT position in temperate zones. Temporally, we show that 70% of CLMT have moved upward, with a mean shift rate of 1.2 m/year over the first decade of the 21st century. CLMT are shifting fastest in the tropics (mean of 3.1 m/year), but with greater variability. Our work provides a new mountain treeline database that isolates climate impacts from other anthropogenic pressures, and has important implications for biodiversity, natural resources, and ecosystem adaptation in a changing climate.