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José R. García

Other affiliations: Sohag University
Bio: José R. García is an academic researcher from University of Oviedo. The author has contributed to research in topics: Crystal structure & Ion exchange. The author has an hindex of 24, co-authored 203 publications receiving 2559 citations. Previous affiliations of José R. García include Sohag University.


Papers
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TL;DR: In this paper, a set of bare and P-doped graphitic carbon nitride (g-C3N4) photocatalysts has been prepared by thermal condensation of melamine, urea or thiourea.
Abstract: A set of bare and P-doped graphitic carbon nitride (g-C3N4) photocatalysts has been prepared by thermal condensation of melamine, urea or thiourea. For the sake of comparison, a g-C3N4 sample obtained in the presence of cyanuric acid and thermally exfoliated C3N4 powders were also studied. The materials were physicochemically characterized and their photocatalytic activity was studied for the selective oxidation of benzyl alcohol (BA), 4-methoxy benzyl alcohol (4-MBA) and piperonyl alcohol (PA) in water suspension both under UV and visible light irradiation. The influence of the type and position of the substituents on conversion and selectivity to aldehyde was remarkable. The presence of P in the C3N4 material improved the selectivity of the reaction towards the aldehyde.

216 citations

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TL;DR: In this paper, the performance of the catalysts increased when the experiments were carried out under real outdoor illumination, reaching 50% of selectivity versus FDC formation at 40% of HMF conversion.
Abstract: Graphitic carbon nitride assisted partial photocatalytic oxidation of 5-hydroxymethyl-2-furfural (HMF) in aqueous medium was investigated. Different carbon nitride precursors were considered, being melamine the one yielding the most efficient photocatalyst. The obtained 30% selectivity of HMF oxidation to 2,5-furandicarboxaldehyde (FDC) is higher than those reported up to now. A further thermal exfoliation of the g-C3N4 samples showed under artificial light irradiation both an enhanced photocatalytic activity in conversion of HMF, and selectivity (ca. 42–45%) to FDC. The performance of the catalysts increased when the experiments were carried out under real outdoor illumination, reaching 50% of selectivity versus FDC formation at 40% of HMF conversion. The utilization of radical scavengers revealed that O2 − was the main reactive species responsible for HMF oxidation to FDC. The photocatalytic test carried out under natural solar irradiation resulted in higher yields of FDC compared to that observed in the laboratory UV irradiated set-up, thus demonstrating the applicability of the exfoliated carbon nitride material in real-life conditions.

143 citations

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TL;DR: Differential scanning calorimetry (DSC) was used to study the melting process of three pure fatty acids (palmitic, stearic and oleic) and both their binary and ternary mixtures as discussed by the authors.

141 citations

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TL;DR: Vyazovkin's model-free kinetic algorithms were applied to determine conversion, isoconversion and apparent activation energy to both dehydration and combustion of sugarcane bagasse.

113 citations

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TL;DR: In this paper, a crystalline α-zirconium phosphate, Zr(HPO4)2·H2O, was obtained by direct precipitation of soluble salts of zirconsimonium(IV) with phosphoric acid.
Abstract: Crystalline α-zirconium phosphate, Zr(HPO4)2·H2O, was obtained by direct precipitation of soluble salts of zirconium(IV) with phosphoric acid. The fresh compound transforms, by hydrolysis, into amo...

99 citations


Cited by
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TL;DR: Corma et al. as mentioned in this paper used the Dupont Award on new materials (1995), and the Spanish National Award “Leonardo Torres Quevedo” on Technology Research (1996) on technology research (1996), to recognize the performance of zeolites as catalysts for oil refining and petrochemistry.
Abstract: It is possible to say that zeolites are the most widely used catalysts in industry They are crystalline microporous materials which have become extremely successful as catalysts for oil refining, petrochemistry, and organic synthesis in the production of fine and speciality chemicals, particularly when dealing with molecules having kinetic diameters below 10 A The reason for their success in catalysis is related to the following specific features of these materials:1 (1) They have very high surface area and adsorption capacity (2) The adsorption properties of the zeolites can be controlled, and they can be varied from hydrophobic to hydrophilic type materials (3) Active sites, such as acid sites for instance, can be generated in the framework and their strength and concentration can be tailored for a particular application (4) The sizes of their channels and cavities are in the range typical for many molecules of interest (5-12 A), and the strong electric fields2 existing in those micropores together with an electronic confinement of the guest molecules3 are responsible for a preactivation of the reactants (5) Their intricate channel structure allows the zeolites to present different types of shape selectivity, ie, product, reactant, and transition state, which can be used to direct a given catalytic reaction toward the desired product avoiding undesired side reactions (6) All of these properties of zeolites, which are of paramount importance in catalysis and make them attractive choices for the types of processes listed above, are ultimately dependent on the thermal and hydrothermal stability of these materials In the case of zeolites, they can be activated to produce very stable materials not just resistant to heat and steam but also to chemical attacks Avelino Corma Canos was born in Moncofar, Spain, in 1951 He studied chemistry at the Universidad de Valencia (1967−1973) and received his PhD at the Universidad Complutense de Madrid in 1976 He became director of the Instituto de Tecnologia Quimica (UPV-CSIC) at the Universidad Politecnica de Valencia in 1990 His current research field is zeolites as catalysts, covering aspects of synthesis, characterization and reactivity in acid−base and redox catalysis A Corma has written about 250 articles on these subjects in international journals, three books, and a number of reviews and book chapters He is a member of the Editorial Board of Zeolites, Catalysis Review Science and Engineering, Catalysis Letters, Applied Catalysis, Journal of Molecular Catalysis, Research Trends, CaTTech, and Journal of the Chemical Society, Chemical Communications A Corma is coauthor of 20 patents, five of them being for commercial applications He has been awarded with the Dupont Award on new materials (1995), and the Spanish National Award “Leonardo Torres Quevedo” on Technology Research (1996) 2373 Chem Rev 1997, 97, 2373−2419

5,290 citations

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TL;DR: This review intends to provide an update of work published since then and focuses on the photoluminescence properties of MOFs and their possible utility in chemical and biological sensing and detection.
Abstract: Metal–organic frameworks (MOFs) are a unique class of crystalline solids comprised of metal cations (or metal clusters) and organic ligands that have shown promise for a wide variety of applications Over the past 15 years, research and development of these materials have become one of the most intensely and extensively pursued areas A very interesting and well-investigated topic is their optical emission properties and related applications Several reviews have provided a comprehensive overview covering many aspects of the subject up to 2011 This review intends to provide an update of work published since then and focuses on the photoluminescence (PL) properties of MOFs and their possible utility in chemical and biological sensing and detection The spectrum of this review includes the origin of luminescence in MOFs, the advantages of luminescent MOF (LMOF) based sensors, general strategies in designing sensory materials, and examples of various applications in sensing and detection

3,485 citations

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TL;DR: The potential of LnMOFs as multifunctional systems, which combine light emission with properties such as microporosity, magnetism, chirality, molecule and ion sensing, catalysis and activity as multimodal imaging contrast agents, is discussed.
Abstract: Metal–organic frameworks based on trivalent lanthanides (LnMOFs) are a very promising class of materials for addressing the challenges in engineering of luminescent centres. Lanthanide-bearing phosphors find numerous applications in lighting, optical communications, photonics and biomedical devices. In this critical review we discuss the potential of LnMOFs as multifunctional systems, which combine light emission with properties such as microporosity, magnetism, chirality, molecule and ion sensing, catalysis and activity as multimodal imaging contrast agents. We argue that these materials present a unique chance of observing synergy between several of these properties, such as the coupling between photoluminescence and magnetism. Moreover, an integrated approach towards the design of efficient, stable, cheap, environmentally-friendly and multifunctional luminescent LnMOFs is still missing. Although research into LnMOFs is at its early stage and much basic knowledge is still needed, the field is ripe for new ideas, which will enable sensor devices and photonic prototypes to become a commercial reality (81 references).

1,384 citations

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TL;DR: In this paper, the state of the art of phase change materials (PCMs) for storing solar energy is discussed. But, prior to the large-scale practical application of this technology, it is necessary to resolve numerous problems at the research and development stage.
Abstract: The continuous increase in the level of greenhouse gas emissions and the climb in fuel prices are the main driving forces behind efforts to more effectively utilise various sources of renewable energy. In many parts of the world, direct solar radiation is considered to be one of the most prospective sources of energy. However, the large-scale utilisation of this form of energy is possible only if the effective technology for its storage can be developed with acceptable capital and running costs. One of prospective techniques of storing solar energy is the application of phase change materials (PCMs). Unfortunately, prior to the large-scale practical application of this technology, it is necessary to resolve numerous problems at the research and development stage. This paper looks at the current state of research in this particular field, with the main focus being on the assessment of the thermal properties of various PCMs, methods of heat transfer enhancement and design configurations of heat storage facilities to be used as a part of solar passive and active space heating systems, greenhouses and solar cooking.

1,173 citations

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TL;DR: This critical review provides an up-to-date survey to this new generation of multifunctional open-framework solids, classified into five different sections: magnetic, chiral, conducting, optical, and labile open-frameworks for sensing applications.
Abstract: The literature on open-framework materials has shown numerous examples of porous solids with additional structural, chemical, or physical properties. These materials show promise for applications ranging from sensing, catalysis and separation to multifunctional materials. This critical review provides an up-to-date survey to this new generation of multifunctional open-framework solids. For this, a detailed revision of the different examples so far reported will be presented, classified into five different sections: magnetic, chiral, conducting, optical, and labile open-frameworks for sensing applications. (413 references.)

989 citations