cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.19901457.v1
title: Polyphenol Profile and Quantitative Assessment of the Flavonoid Kaempferitrin in Wild and Cultivated Brazilian Amazonian Uncaria guianensis (Rubiaceae)

description: The Amazonian Rubiaceae species Uncaria guianensis (UG) is locally used as anti-inflammatory, antitumor, antidiabetic, anti-ulcers, and others. The phenolic content of its leaves is characterized by the great predominance of the flavonoid kaempferol-3,7-O-(α)-L-dirhamnoside (kaempferitrin). The present study quantitatively evaluates the kaempferitrin content in the leaves and branches of cultivated and wild UG specimens collected in different locations of the Brazilian Amazon rainforest by employing high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD). Besides, the understanding of the polyphenol profile performed by electron spray ionization is deepened by tandem mass spectrometry analysis (ESI-MS/MS), using a previously approached leaf UG extract, and the flavonoid quercetin-3,7-O-(α)-L-dirhamnoside was first isolated from UG. All samples showed quite similar qualitative polyphenol profiles. Kaempferitrin in UG ranged from 1.1 to 1.9 mg 100 mg-1 for dry leaves of adult wild plants, 0.3 to 0.7 mg 100 mg-1 for dry leaves of cultivated young plants and 0.00 to 0.04 mg 100 mg-1 for dry branches of adult wild plants. Besides suggesting the distribution of kaempferitrin in the species, these results reinforce this flavonol as a suitable chemical marker for UG leaves and the products derived from them.
DOI: 10.6084/m9.figshare.19901476
title: QUANTIFICATION OF MULLITE FROM KAOLIN WASTES FROM THE AMAZON REGION: USE OF THE RIETVELD METHOD

description: Mullite is used to obtain a refractory material, there are several factors that influence the synthesis process of mullite: the preparation of the mixture, the precipitation and the reaction of SiO2 and Al2O3. For the synthesis of mullite, samples of kaolin processing residues were used as precursor material, because it presents SiO2 and Al2O3 in its composition. This work aimed to identify, by X-ray diffraction, and quantify the mineral phases present in samples of kaolin processing residues from the Amazon region calcined at 1300, 1400 and 1500 ºC, using the Rietveld method. The method allowed the refinement of the complex crystalline structures and was applied to the data supply for quantitative analyses with satisfactory results of good accuracy. The results of the quantification of crystalline and non-crystalline phases (with internal standard) in the samples calcined at 1500 ºC presented approximate values of mullite (62%), cristobalite (32%) and non-crystalline phases (6%), for both samples, indicating that the refinement model applied is optimal. These results obtained from the quantification of the phases by the method of Rietveld are presenting coherent and satisfactory values, in comparison with the theoretical ones by the phase diagram Al2O3 and SiO2.
DOI: 10.6084/m9.figshare.19901476.v1
title: QUANTIFICATION OF MULLITE FROM KAOLIN WASTES FROM THE AMAZON REGION: USE OF THE RIETVELD METHOD

description: Mullite is used to obtain a refractory material, there are several factors that influence the synthesis process of mullite: the preparation of the mixture, the precipitation and the reaction of SiO2 and Al2O3. For the synthesis of mullite, samples of kaolin processing residues were used as precursor material, because it presents SiO2 and Al2O3 in its composition. This work aimed to identify, by X-ray diffraction, and quantify the mineral phases present in samples of kaolin processing residues from the Amazon region calcined at 1300, 1400 and 1500 ºC, using the Rietveld method. The method allowed the refinement of the complex crystalline structures and was applied to the data supply for quantitative analyses with satisfactory results of good accuracy. The results of the quantification of crystalline and non-crystalline phases (with internal standard) in the samples calcined at 1500 ºC presented approximate values of mullite (62%), cristobalite (32%) and non-crystalline phases (6%), for both samples, indicating that the refinement model applied is optimal. These results obtained from the quantification of the phases by the method of Rietveld are presenting coherent and satisfactory values, in comparison with the theoretical ones by the phase diagram Al2O3 and SiO2.
DOI: 10.6084/m9.figshare.19901487
title: CHEMICAL MODIFICATION OF POLYPROPYLENE THROUGH THE INTRODUCTION OF SULPHONIC GROUPS FOR APPLICATION AS CATALYST IN ESTERIFICATION REACTIONS.

description: In this work, the chemical modification of pristine polypropylene was carried out through sulfonation reactions with concentrated sulfuric acid (PPS1) and fuming sulfuric acid (PPS2), for production of heterogeneous catalysts used in esterification reactions. Fourier transform infrared spectroscopy, elemental analysis, degree of substitution and ion exchange capacity showed that both sulfonation agents were effective to promote the functionalization of polypropylene, with the fuming sulfuric acid capable of promoting a greater chemical modification. The materials catalytic activity in esterification reaction of oleic acid with methanol was evaluated at 100 ºC, methanol: oleic acid molar ratio of 78:1 and with 5 wt% of catalyst (referred to oleic acid weight). It was observed that reaction catalyzed by PPS1 converted 68.02% of oleic acid to methyl oleate in 3 hours of reaction, while PPS2 reached 86.47% conversion in five hours, showing even greater catalytic efficiency than the commercial ion exchange resin, Amberlyst 15. Therefore, the conditions employed for the sulfonation of polypropylene were satisfactory to produce materials with acid characteristics necessary to catalyze the esterification reaction of oleic acid with methanol.
DOI: 10.6084/m9.figshare.19901487.v1
title: CHEMICAL MODIFICATION OF POLYPROPYLENE THROUGH THE INTRODUCTION OF SULPHONIC GROUPS FOR APPLICATION AS CATALYST IN ESTERIFICATION REACTIONS.

description: In this work, the chemical modification of pristine polypropylene was carried out through sulfonation reactions with concentrated sulfuric acid (PPS1) and fuming sulfuric acid (PPS2), for production of heterogeneous catalysts used in esterification reactions. Fourier transform infrared spectroscopy, elemental analysis, degree of substitution and ion exchange capacity showed that both sulfonation agents were effective to promote the functionalization of polypropylene, with the fuming sulfuric acid capable of promoting a greater chemical modification. The materials catalytic activity in esterification reaction of oleic acid with methanol was evaluated at 100 ºC, methanol: oleic acid molar ratio of 78:1 and with 5 wt% of catalyst (referred to oleic acid weight). It was observed that reaction catalyzed by PPS1 converted 68.02% of oleic acid to methyl oleate in 3 hours of reaction, while PPS2 reached 86.47% conversion in five hours, showing even greater catalytic efficiency than the commercial ion exchange resin, Amberlyst 15. Therefore, the conditions employed for the sulfonation of polypropylene were satisfactory to produce materials with acid characteristics necessary to catalyze the esterification reaction of oleic acid with methanol.
DOI: 10.6084/m9.figshare.19901512
title: FRITZ HABER VISIT TO BRAZIL

description: Fritz Haber was awarded with the Nobel Prize in Chemistry in 1918 for the ammonia synthesis from its gaseous components. This work was fundamental to stop starvation around the world. On the opposite, his engagement to produce chemical weapons during the First World War is also an important fact in the life of this scientist. This polemic scientist visited Brazil in 1923, carrying out a project to extract gold from the sea. The present work tries to recover the historical fact behind the visit of this scientist to Brazil.
DOI: 10.6084/m9.figshare.19901512.v1
title: FRITZ HABER VISIT TO BRAZIL

description: Fritz Haber was awarded with the Nobel Prize in Chemistry in 1918 for the ammonia synthesis from its gaseous components. This work was fundamental to stop starvation around the world. On the opposite, his engagement to produce chemical weapons during the First World War is also an important fact in the life of this scientist. This polemic scientist visited Brazil in 1923, carrying out a project to extract gold from the sea. The present work tries to recover the historical fact behind the visit of this scientist to Brazil.
DOI: 10.6084/m9.figshare.14279023
title: THE FUNDAMENTAL IMPORTANCE OF BASIC SCIENCE: EXAMPLES OF HIGH-IMPACT DISCOVERIES FROM AN INTERNATIONAL CHEMISTRY NETWORK

description: During the last 150 years or more, society has witnessed many key scientific discoveries and inventions, which have dramatically improved not only our quality of life, but our lifespan. However, the motivation of scientists to provide scientific advances has generally not been the achievement of these goals, but mainly driven by research curiosity. Fundamental scientific studies, also known as basic science, have paved the way to a society of knowledge by means of continuously evolving education systems, and have led to applied science and technological breakthroughs changing the World. However, without basic science such life-changing advances would not happen, which is poorly understood by the society. Having this in mind, chemists and biochemists working in a chemistry network highlight here examples of how basic science has played a crucial role and led to major breakthroughs. In seven short stories, the authors describe cases and historical events where basic research discoveries have advanced science, and opened avenues for future achievements. Investment in basic science is crucial for a nation’s health and wealth. The support of scientists driven by curiosity ultimately can benefit the whole of society, not only in innovative products, but also in the improvement of the understanding of our own lives.
DOI: 10.6084/m9.figshare.14279023.v1
title: THE FUNDAMENTAL IMPORTANCE OF BASIC SCIENCE: EXAMPLES OF HIGH-IMPACT DISCOVERIES FROM AN INTERNATIONAL CHEMISTRY NETWORK

description: During the last 150 years or more, society has witnessed many key scientific discoveries and inventions, which have dramatically improved not only our quality of life, but our lifespan. However, the motivation of scientists to provide scientific advances has generally not been the achievement of these goals, but mainly driven by research curiosity. Fundamental scientific studies, also known as basic science, have paved the way to a society of knowledge by means of continuously evolving education systems, and have led to applied science and technological breakthroughs changing the World. However, without basic science such life-changing advances would not happen, which is poorly understood by the society. Having this in mind, chemists and biochemists working in a chemistry network highlight here examples of how basic science has played a crucial role and led to major breakthroughs. In seven short stories, the authors describe cases and historical events where basic research discoveries have advanced science, and opened avenues for future achievements. Investment in basic science is crucial for a nation’s health and wealth. The support of scientists driven by curiosity ultimately can benefit the whole of society, not only in innovative products, but also in the improvement of the understanding of our own lives.
DOI: 10.6084/m9.figshare.19901527.v1
title: CLASSIFICATION OF CHEMICAL SUBSTANCES: A LITTLE-EXPLORED CONCEPT IN CHEMICAL EDUCATION

description: The classification of chemical substances is a concept little explored in Chemistry teaching literature and in Chemistry textbooks at higher and secondary levels. The aim of this paper is to discuss theoretically the importance and contributions of this concept for teaching and learning Chemistry. The History of Chemistry reveals that the chemical criteria for classifying materials came up with the modern concepts of chemical element and chemical reaction, which gave rise to the notion of chemical similarity. Later, such similarity was related to molecular structure through functional groups. The classes of substances are related throughout chemical reactions, during which substances of given classes are transformed into substances of other classes, constituting a wide network. The classification of chemical substances can contribute to the intellectual development of Chemistry students, in order to study it, it becomes necessary to understand its theoretical foundation, as well as its characteristics of objectivity, completeness, simplicity and prediction. In this sense, one can contribute to the stimulation of perception, attention and abstraction that are typical of the chemical ways of thinking and communicating necessary for learning the chemical concepts linked to classification.
DOI: 10.6084/m9.figshare.19901527
title: CLASSIFICATION OF CHEMICAL SUBSTANCES: A LITTLE-EXPLORED CONCEPT IN CHEMICAL EDUCATION

description: The classification of chemical substances is a concept little explored in Chemistry teaching literature and in Chemistry textbooks at higher and secondary levels. The aim of this paper is to discuss theoretically the importance and contributions of this concept for teaching and learning Chemistry. The History of Chemistry reveals that the chemical criteria for classifying materials came up with the modern concepts of chemical element and chemical reaction, which gave rise to the notion of chemical similarity. Later, such similarity was related to molecular structure through functional groups. The classes of substances are related throughout chemical reactions, during which substances of given classes are transformed into substances of other classes, constituting a wide network. The classification of chemical substances can contribute to the intellectual development of Chemistry students, in order to study it, it becomes necessary to understand its theoretical foundation, as well as its characteristics of objectivity, completeness, simplicity and prediction. In this sense, one can contribute to the stimulation of perception, attention and abstraction that are typical of the chemical ways of thinking and communicating necessary for learning the chemical concepts linked to classification.
DOI: 10.6084/m9.figshare.19901535
title: Smart Tourism Destinations: (Mis)Aligning Touristic Destinations and Smart City Initiatives

description: ABSTRACT Several tourism destinations around the world have started to implement smart city projects with the aim of improving the standard of living of their citizens, as well as the sustainability of their urban and touristic areas, which motivated the emergence of the concept of smart tourism destination. However, the extant literature on this subject is still incipient. Thus, this article aims to investigate, via an exploratory case study, whether the implementation of a smart city initiative in a touristic destination has helped it be transformed into a smart tourism destination. For that, a smart tourism destination development model is presented and applied as the theoretical lens adopted in this research. The results showed a clear misalignment between the smart city initiative and the touristic destination analyzed, as despite the opportunities arising from the technological infrastructure provided by the smart city project, the touristic sector of the city under analysis was not able to take advantage of the opportunities enabled by the smart city project. Lastly, one concluded that political discontinuity, missing local government tourism strategy and governance, lack of engagement of the citizens, and disregard for the local context were the main reasons for that misalignment.
DOI: 10.6084/m9.figshare.19901535.v1
title: Smart Tourism Destinations: (Mis)Aligning Touristic Destinations and Smart City Initiatives

description: ABSTRACT Several tourism destinations around the world have started to implement smart city projects with the aim of improving the standard of living of their citizens, as well as the sustainability of their urban and touristic areas, which motivated the emergence of the concept of smart tourism destination. However, the extant literature on this subject is still incipient. Thus, this article aims to investigate, via an exploratory case study, whether the implementation of a smart city initiative in a touristic destination has helped it be transformed into a smart tourism destination. For that, a smart tourism destination development model is presented and applied as the theoretical lens adopted in this research. The results showed a clear misalignment between the smart city initiative and the touristic destination analyzed, as despite the opportunities arising from the technological infrastructure provided by the smart city project, the touristic sector of the city under analysis was not able to take advantage of the opportunities enabled by the smart city project. Lastly, one concluded that political discontinuity, missing local government tourism strategy and governance, lack of engagement of the citizens, and disregard for the local context were the main reasons for that misalignment.
DOI: 10.6084/m9.figshare.19901559
title: MACROALGAE Fucus vesiculosus OIL: BIODIESEL PRODUCTION USING ALKALINE TRANSESTERIFICATION

description: This work studied the obtaining of methyl biodiesel and ethyl biodiesel using alkaline transesterification from macroalgae Fucus vesiculosos oil (FVO). FVO has 86.59% of its composition in unsaturated fatty acids, with a greater quantity of linoleic acid and oleic acid, a chemical composition near the soybean oil, the most used raw material for the production of biodiesel. Linoleic acid (47.88%), and oleic acid (34.66%) are the fatty acids present in the greatest amount in FVO, and unsaturated fatty acids correspond to 86.59% the composition of FVO, a composition of fatty acids close to that of soybean oil, which is the oil most produced and used for the production of biodiesel. To obtain methyl biodiesel (MBFVO) and ethyl biodiesel (EBFVO) the molar ratio oil: alcohol 1: 3 and 1% alkaline catalyst, NaOH, was used. The yield of the transesterification reaction was evaluated by varying the reaction time between 30 and 60 minutes and the highest yields were obtained after 60 minutes of reaction. In order to check the quality of the obtained biodiesel, the properties acidity index, iodine value, water content, specific mass at 20 ºC, oxidative stability, cold filter plugging point and kinematic viscosity were evaluated. The oxidative stability had an induction period below the recommended, but it can be corrected with the addition of antioxidants to the biodiesel. All other physical and chemical properties had values within the stipulated by the regulatory agencies, indicating that the macroalgae Fucus vesiculosus can be a raw material in potential for production of biodiesel.
DOI: 10.6084/m9.figshare.19901559.v1
title: MACROALGAE Fucus vesiculosus OIL: BIODIESEL PRODUCTION USING ALKALINE TRANSESTERIFICATION

description: This work studied the obtaining of methyl biodiesel and ethyl biodiesel using alkaline transesterification from macroalgae Fucus vesiculosos oil (FVO). FVO has 86.59% of its composition in unsaturated fatty acids, with a greater quantity of linoleic acid and oleic acid, a chemical composition near the soybean oil, the most used raw material for the production of biodiesel. Linoleic acid (47.88%), and oleic acid (34.66%) are the fatty acids present in the greatest amount in FVO, and unsaturated fatty acids correspond to 86.59% the composition of FVO, a composition of fatty acids close to that of soybean oil, which is the oil most produced and used for the production of biodiesel. To obtain methyl biodiesel (MBFVO) and ethyl biodiesel (EBFVO) the molar ratio oil: alcohol 1: 3 and 1% alkaline catalyst, NaOH, was used. The yield of the transesterification reaction was evaluated by varying the reaction time between 30 and 60 minutes and the highest yields were obtained after 60 minutes of reaction. In order to check the quality of the obtained biodiesel, the properties acidity index, iodine value, water content, specific mass at 20 ºC, oxidative stability, cold filter plugging point and kinematic viscosity were evaluated. The oxidative stability had an induction period below the recommended, but it can be corrected with the addition of antioxidants to the biodiesel. All other physical and chemical properties had values within the stipulated by the regulatory agencies, indicating that the macroalgae Fucus vesiculosus can be a raw material in potential for production of biodiesel.
DOI: 10.6084/m9.figshare.19228422
title: DedA

description: I-Tasser was used to construct this <i>Neisseria gonorrhoeae</i> DedA model using the hm_build and hm_refine macros. The sequence used to create this model corresponds to <i>dedA </i>allele 469 (https://pubmlst.org/bigsdb?db=pubmlst_neisseria_seqdef&page=alleleInfo&locus=NEIS1016&allele_id=469), which is the allele occurring in isolate SRR3360624 (Archived in The Sequence Read Archive at National Center for Biotechnology Information Search database (NCBI SRA) with Accession ID SRR3360624 and in the <i>Neisseria </i>PubMLST database with accession ID 48638). This model is used in the manuscript "A naturally occurring <i>Neisseria gonorrhoeae</i> without a functional <i>abcZ </i>gene" by Hilde Synnøve Vollan, Dominique A. Caugant, Vegard Eldholm, Kristian Alfsnes, Nadia Debech and Ola Brynildsrud.
DOI: 10.6084/m9.figshare.19323809
title: AbcZ

description: YASARA Structure & WHATIF twinset software v19.7.5 was used to construct this <i>Neisseria gonorrhoeae</i> AbcZ homology model using the hm_build and hm_refine macros. The sequence used to create this model corresponds to <i>abcZ </i>allele 59 (https://pubmlst.org/bigsdb?db=pubmlst_neisseria_seqdef&page=alleleInfo&locus=abcZ&allele_id=59), which is the allele occurring in isolate SRR3360624 (Archived in The Sequence Read Archive at National Center for Biotechnology Information Search database (NCBI SRA) with Accession ID SRR3360624 and in the <i>Neisseria </i>PubMLST database with accession ID 48638). This model is used in the manuscript "A naturally occurring <i>Neisseria gonorrhoeae </i>without a functional <i>abcZ </i>gene" by Hilde Synnøve Vollan, Dominique A. Caugant, Vegard Eldholm, Kristian Alfsnes, Nadia Debech and Ola Brynildsrud.
DOI: 10.6084/m9.figshare.19323809.v1
title: AbcZ

description: YASARA Structure & WHATIF twinset software v19.7.5 was used to construct this <i>Neisseria gonorrhoeae</i> AbcZ homology model using the hm_build and hm_refine macros. The sequence used to create this model corresponds to <i>abcZ </i>allele 59 (https://pubmlst.org/bigsdb?db=pubmlst_neisseria_seqdef&page=alleleInfo&locus=abcZ&allele_id=59), which is the allele occurring in isolate SRR3360624 (Archived in The Sequence Read Archive at National Center for Biotechnology Information Search database (NCBI SRA) with Accession ID SRR3360624 and in the <i>Neisseria </i>PubMLST database with accession ID 48638). This model is used in the manuscript "A naturally occurring <i>Neisseria gonorrhoeae </i>without a functional <i>abcZ </i>gene" by Hilde Synnøve Vollan, Dominique A. Caugant, Vegard Eldholm, Kristian Alfsnes, Nadia Debech and Ola Brynildsrud.