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Literatura académica sobre el tema "FePO4"

Autor: Grafiati

Publicado: 11 de marzo de 2023

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Artículos de revistas sobre el tema "FePO4"

Jing, Hai Li, Guo Jun Li y Rui Ming Ren. "Preparation and Characteristics of FePO₄·xH₂O Powder". Materials Science Forum 675-677 (febrero de 2011): 77–80. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.77.

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Nano-sized precursor FePO4·xH2O particles were obtained by oxidation co-precipitation using FeSO4⋅7H2O, H2O2 and ammonia. The powder was characterized by differential thermal analysis (DTA) and thermogravimetry (TG), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The TG-DTA results determined the content of crystal water of FePO4·xH2O, i.e. x = 1.5. The SEM observation suggested that FePO4·xH2O particles were spherical in shape and its grain size was about 150 nanometers. The dispersion of the synthesized powder was improved through the addition of surfactant. The XRD analysis indicated that the synthesized FePO4·xH2O was amorphous. After being calcined at 720 °C for 10 hrs, the synthesized FePO4·xH2O at pH of ~3.5 was crystallized and FePO4 in a single phase was obtained. According to the test results, the optimized preparation process parameters were determined.

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Manickam, Minakshi, Pritam Singh, Touma B. Issa, Stephen Thurgate y Kathryn Prince. "Electrochemical Behavior of LiFePO₄ in Aqueous Lithium Hydroxide Electrolyte". Key Engineering Materials 320 (septiembre de 2006): 271–74. http://dx.doi.org/10.4028/www.scientific.net/kem.320.271.

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The electrochemistry of olivine-type iron phosphate (FePO4) as a battery cathode material, in aqueous lithium hydroxide (LiOH), has been investigated. The material forms intercalated LiFePO4 reversibly on electroreduction/oxidation. The formation of Fe3O4 phase, in addition to the regeneration of FePO4 during reverse oxidation of LiFePO4, also occurs. In this regard, the mechanism of FePO4 discharge/charge in aqueous LiOH differs from that in non-aqueous solvents.

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Wang, Huiqi, Mingxia Guo, Yue Niu, Jiayu Dai, Qiuxiang Yin y Ling Zhou. "Study on Precipitation Processes and Phase Transformation Kinetics of Iron Phosphate Dihydrate". Crystals 12, n.º 10 (27 de septiembre de 2022): 1369. http://dx.doi.org/10.3390/cryst12101369.

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The process of the phase transformation from amorphous to crystalline FePO4·2H2O was studied in this research. It was found that Fe and P are predominantly present as FeHPO4+ and FeH2PO42+ and an induction period exists during the transition from amorphous to monoclinic form. The induction period and the time required for phase transformation were shortened with the increased temperature. Phase transformation could be kinetically described by the Johnson–Mehl–Avrami (JMA) dynamics model. The dissolution rate of amorphous FePO4·2H2O is the rate-limiting step of this process. the activation energy of phase transformation is calculated to be 9.619 kJ/mol. The results in this study provided more guidelines for the regulation of FePO4·2H2O precursors by precipitation method.

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Ma, Jun Jun, Jia Zhou, Xue Min Zu y Xing Yao Wang. "Study of Circulation of Reaction Liquid in Liquid Phase Synthesis of LiFePO4 as Cathode Material". Advanced Materials Research 1120-1121 (julio de 2015): 128–31. http://dx.doi.org/10.4028/www.scientific.net/amr.1120-1121.128.

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LiFePO4 as cathode materials for lithium-ion battery were prepared by a liquid-phase method which utilizes FeSO4•7H2O, NH4H2PO4, H2O2, CH3COOLi and glucose as raw materials. The aqueous can be directly used in the synthesis of FePO4•xH2O without any treatment and the ethanol should be distilled before the synthesis of LiFePO4. The result showed that the high purity of FePO4•xH2O can be achieved even prepared with the aqueous which was used for five times. LiFePO4 cathode material prepared with the distilled ethanol exhibited the best initial discharge capacity of 156.3 mAh•g-1 and the capacity retention ratio 99.49% after 30 cycles at 0.1 C rate.

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Saveetha, S. y K. A. Vijayalakshmi. "The morphological study of FePO4/plasma treated bamboo charcoal composite act as cathode material in energy storage devices". Digest Journal of Nanomaterials and Biostructures 16, n.º 4 (diciembre de 2021): 1359–63. http://dx.doi.org/10.15251/djnb.2021.164.1359.

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The capacity of energy storage devices to be based on the cathode material with best morphology. The FePO4 nanoparticles were synthesized by hydrothermal method and Bamboo charcoal (BCC) was synthesized and activated by pyrolysis method. The cold Plasma was used to magnify the surface behaviour of activated Bamboo Charcoal. The hybrid composite of FePO4/Plasma exposed BCC and pure FePO4 nano materials morphological and structural properties were analysed through XRD, FTIR and SEM characterization studies. This research reveals that the Plasma exposed BCC nanoparticles were well incorporate with FePO4 nanoparticles and delivered embedded FePO4 nanoparticles. The result shows that the FePO4/plasma exposed BCC particle size was decreased when compare to pure FePO4, which in turn increase the energy storage capacity of the material.

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Cao, Ying, Lianmei Wei, Xianzhen Song, Xixi Yan, Xiaoyu Liu y Lijun Wang. "Synthesis of iron phosphate-SAPO-34 composite and its application as effective absorbent for wastewater treatment". MATEC Web of Conferences 238 (2018): 02003. http://dx.doi.org/10.1051/matecconf/201823802003.

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High-purity FePO4 was purified from iron-based phosphating slag as raw material, and FePO4@SAPO-34 was synthesized by hydrothermal crystallization method under the action of templating agent-diethylamine. The synth esized FePO4@SAPO-34 samples were characterized by x-ray diffraction (XRD), scanning electron microscopy (SE M) and Fourier transform infrared spectroscopy (FT-IR). The effects of different crystallization time on the morpholo gy and crystallization of FePO4@SAPO-34 crystals were investigated. The removal of heavy metal ion wastewater by low-cost FePO4@SAPO-34 was investigated. The experimental results show that when the reaction time is 180 °C an d the reaction time is 72h, the crystallization of FePO4@SAPO-34 is the best. When the dosage is 0.6g, the removal efficiency of heavy metal ions is the highest.

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Jiang, Bing, Wen Qin Wang, Yu Song Liu y Zhi Meng Guo. "Preparation of FePO₄•2H₂O with Flower-like Microstructure by a Facile Hydrothermal Synthesis Method". Applied Mechanics and Materials 423-426 (septiembre de 2013): 550–53. http://dx.doi.org/10.4028/www.scientific.net/amm.423-426.550.

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FePO4·2H2O with orthorhombic flower-like microstructure was synthesized by a facile hydrothermal process which was of low-cost and easy processing in large area. The formation mechanism of the flower-like FePO4·2H2O was discussed in details by investigating the different concentration of reactants and reaction time. The results show that the morphology of FePO4·2H2O changed from microsphere to flower-like structure, which possess an unique morphology with six petals and the angle of each petal being 60o. The formation mechanism of FePO4·2H2O flowers can be explained by the dissolution-recrystallization and crystal splitting.

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Sun, Yuan, Xiu Juan Zhao y Rui Ming Ren. "Synthesis of LiFePO₄ Cathode Materials by a Chemical Method". Materials Science Forum 675-677 (febrero de 2011): 57–60. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.57.

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The olivine-type LiFePO4 powder was prepared by a chemical method using the synthesized FePO4⋅2H2O, LiOH and glucose as raw materials. The synthesized FePO4⋅2H2O powder was obtained by co-precipitation method. FePO4⋅2H2O and LiFePO4 powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed the synthesized FePO4⋅2H2O powder at pH of 2.05 was in a single phase and nearly spherical in shape. Using the synthesized powders to prepared LiFePO4 at 600 °C in vacuum for 2 h was nearly spherical in shape and whose size was in the range of 0.1-0.5μm.

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Park, Yejun, Byungjoo Lee, Chunjoong Kim, Jongmin Kim y Byungwoo Park. "Effects of iron-phosphate coating on Ru dissolution in the PtRu thin-film electrodes". Journal of Materials Research 24, n.º 1 (enero de 2009): 140–44. http://dx.doi.org/10.1557/jmr.2009.0013.

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The effects of FePO4 nanoscale coating on PtRu thin films were investigated on the block of Ru crossover. Ru dissolution was examined by the accelerated-potential cycles between 0.4 and 1.05 V. The results showed that Ru dissolution from FePO4-coated PtRu surface was inevitable due to the direct contact between the PtRu surface and aqueous electrolyte. However, the FePO4 coating layer on PtRu thin-film electrodes effectively retained the dissolved Ru species, thus preventing the dissolved Ru species from diffusing into the electrolyte. Moreover, the retained Ru species within the FePO4-coating layer were redeposited onto the PtRu surface during the cycling in the fresh electrolyte.

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Mu, Long Fei, Song Li y Yun Long Cui. "Effects of Different Ligands Value on the Synthesis of FePO₄ Precursor". Materials Science Forum 809-810 (diciembre de 2014): 267–71. http://dx.doi.org/10.4028/www.scientific.net/msf.809-810.267.

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This FePO4 precursor was synthesized from Fe (NO3)3·9H2O, NH4H2PO4 ,different ligands by liquid precipitation route. Effects of different ligands value on the synthesis of FePO4 precursor were studied. The phrase, structure and morphology of FePO4 were characterized by XRD and SEM . The results showed that the structure and morphology of composite materials are dependence on synthesis process and complexant. After being added with different ligands, FePO4 precursor’s morphologies have significant differences. Iron phosphate can produce the pure phase after calcinations. Keep it under 85°C for three hours after adding the citric acid and ammonium oxalate by liquid phase precipitation.When the concentration is 1.0 mol/L, PH = 1.5 ,we get flaky microspheres which are about 8 um. After being calcinated under 700°C for 2 hours, we get pure iron phosphate finally. The properties of micro ball with high specific surface area and tap density make FePO4 precursor has important applications in many ways.

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Tesis sobre el tema "FePO4"

Intaranont, Noramon. "Selective lithium extraction from salt solutions by chemical reaction with FePO4". Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/382486/.

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The spectacular increase in lithium battery applications has raised the question of whether global lithium resources will be enough in the future. Experts in the field have estimated that the existing lithium resources will probably be sufficient to support demands until the year 2100, assuming that lithium batteries are recycled. Without lithium batteries being recycled, the resources are expected to be depleted in 50 years’ time. Therefore, there is a great interest in developing better methods of lithium recycling from batteries, and also, better methods of lithium extraction from natural resources. Currently, lithium is extracted from natural brines via the lime soda evaporation process, i.e. a solar evaporation plus chemical plant process, which takes between 12 and 24 months. The drawbacks of this process are that it is complex, slow and inefficient. Also, the currently available methods of lithium recycling from batteries are too complex and expensive. Thus, the main objective of this work is to develop a novel, inexpensive and less timeconsuming approach to recover lithium chemically, from the lithium salts (lithium sources) that contain other metal cations. The new process is also based on environmental concerns. A battery material, lithium iron phosphate (LiFePO4) has the olivine structure and heterosite structure once it discharges to iron phosphate (FePO4). This structure shows excellent properties of the charge/discharge reversibility. A few studies on the heterosite FePO4 have reported that it is more selective for lithium ions (Li+) over other cations. The main advantages of this structure are the small potential differences of the redox couple, i.e. Fe(II)/Fe(III), and the stability of LiFePO4 over a wide range of acid-based conditions in an aqueous solution. This work investigates a novel process that may be superior to the lime soda evaporation process for extracting lithium. Heterosite FePO4 was employed to selectively remove Li+ from lithium sources with the support of a reducing agent, i.e. sodium thiosulphate (Na2S2O3). The resulting LiFePO4 can be directly sent not only to lithium battery industries, but also to other industrial uses. In principle, the other cations could be retrieved back into their sources. The novel process was examined and demonstrated lithium insertion into a heterosite FePO4, working as a framework, in aqueous salt solutions. The evaluation of this process is presented by the Li+ uptake value. The amount of Li+ uptake can be up to 46 mgLi +/gsolid where other cations (i.e. sodium, potassium, and magnesium) can take less than 3 mg/gsolid, using this process. Furthermore. This work could also be developed for future lithium recycling processes.

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Zhu, Changbao [Verfasser] y Joachim [Akademischer Betreuer] Maier. "Size effects on lithium storage and phase transition in LiFePO4/FePO4 system / Changbao Zhu. Betreuer: Joachim Maier". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2013. http://d-nb.info/1036874680/34.

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Aliouane, Nadir. "Transitions de phase α-β dans le quartz et FePO4 : relations avec la diffusion anomale de la lumière et mécanismes". Toulon, 2002. http://www.theses.fr/2002TOUL0012.

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Lachal, Marie. "Etude des mécanismes d'insertion/désinsertion des cations alcalins (Li+/Na+) au sein de la structure olivine FePO4 pour accumulateurs Li-ion et Na-ion". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAI035/document.

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Dans le cadre du développement des technologies Na-ion, le composé NaFePO4, équivalent chimiquedu matériau très attractif LiFePO4, représente une alternative intéressante aux problèmes deressourcement du lithium. Toutefois, les composés LiFePO4 et NaFePO4 de structure olivineprésentent des divergences de comportement structural et électrochimique lors de l'insertioncationique. Ce travail présente une analyse des mécanismes de (dés)insertion des ions Li+ et Na+ ausein de la phase FePO4 par voie chimique et électrochimique. Les échantillons de LiFePO4 ont étésynthétisés par deux méthodes différentes (hydrothermale et précipitation), puis délithiéschimiquement via différents procédés. Dans un premier temps, les analyses structurales (DRX)associées aux analyses nucléaires ont permis d'effectuer un suivi de la cinétique de réaction. Nousavons montré que la présence de joints de grains, issus du traitement thermique effectué, limitefortement la vitesse de délithiation. L'analyse de l’évolution des domaines de cohérences a permis deproposer un mécanisme de délithiation original de type "Coeur-Coquille" avec un coeur de LiFePO4,confirmé par HRTEM et STEM-EELS. Dans un deuxième temps, afin de comparer les mécanismes dedélithiation chimique et électrochimique, l’insertion et la cyclabilité des ions Li+ et Na+ ont étécaractérisées en demi-cellules lithium et sodium. Bien que la signature électrochimique des matériauxLiFePO4 et NaFePO4 soit différente, les performances en termes de capacité restituée ou de tenue enpuissance s'avèrent similaires. Enfin, l'insertion électrochimique des ions Li+ et Na+ au sein d'unepoudre comportant des défauts structuraux a été caractérisée par DRX Operando durant un cycle decharge / décharge effectué à régime lent. Ces analyses ont révélées que la co-insertion cationiques'effectue via une solution solide de type LixNayFePO4 (0
As part of the development of Na-ion technology, NaFePO4 compound, chemical equivalent of theattractive LiFePO4 material, would be a promising option facing possible lithium shortage. However,olivine-type LiFePO4 and NaFePO4 display different structural and electrochemical behaviors duringcationic insertion. This thesis presents an analysis of the (de)insertion mechanisms of Li+ and Na+ ionswithin olivine-type FePO4 by chemical and electrochemical means. Samples of LiFePO4 weresynthesized by two different methods (hydrothermal and precipitation), then chemically delithiated bydifferent processes. In a first step, structural analysis (XRD) associated with nuclear analyses enabledfollowing the reaction kinetics. We have pointed out that the presence of grain boundaries, resultingfrom the heat treatment, strongly limits the delithiation kinetics. The analysis of the evolution of thecoherency domains enabled us to propose an original "Shrinking Core" type delithiation mechanismwith a core of LiFePO4, observed by HRTEM and STEM-EELS. In a second step, in order to comparechemical and electrochemical mechanisms, insertion and cyclability of Li+ and Na+ were characterizedin lithium and sodium half-cells. Although the electrochemical signature of LiFePO4 and NaFePO4materials is different, the performances in terms of restored capacity or power capability are similar.Finally, electrochemical insertion of Li+ and Na+ in a powder comprising structural defects wascharacterized by operando XRD, during a charge / discharge cycle performed at low rate. Theseanalyses revealed that the cationic co-insertion takes place via a solid solution LixNayFePO4(0

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Matos, Izabela Teles de. "Caracterização em escala atômica de nanopartículas magnéticas de magnetita e ferrita do tipo TMFe2O4 (TM = Co, Ni) para uso em biomedicina pela espectroscopia de correlação angular gama-gama perturbada". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-30012019-144245/.

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Este trabalho descreve, sob um ponto de vista atômico, a investigação das nanopartículas magnéticas (NPMs) de magnetita (Fe3O4) e ferritas do tipo TMFe2O4 (TM = Co, Ni), que são uma classe de materiais estruturados que atualmente tem um grande interesse devido à grande variedade de suas possíveis aplicações tecnológicas e biomédicas, pela Espectroscopia de Correlação Angular γ-γ Perturbada (CAP). Para a produção das NPMs foram utilizadas duas rotas químicas: o método de co-precipitação e o método de decomposição térmica. A co-precipitação apresenta as vantagens de ter temperaturas moderadas e custos relativamente baixos, porém não se consegue ter um controle da distribuição de tamanho das partículas. Por outro lado, a decomposição térmica possibilita uma amostra monodispersa com controle de tamanho e forma, mas este método necessita de reagentes tóxicos, caros e alta temperatura de reação. Para caracterização das amostras foi usada a técnica de Difração de Raio X (DRX) e a morfologia das NPs foi estudada por meio da Microscopia Eletrônica de Transmissão (MET). A partir desta técnica foi possível avaliar a distribuição do tamanho dos grãos, pois algumas características como, elevado valor de magnetização, alta anisotropia e um alto valor de coercividade são propriedades que dependem das nanoestruturas. As propriedades magnéticas foram estudadas localmente a partir da Correlação Angular Perturbada (CAP) que utiliza como sondas núcleos atômicos das medidas, como os núcleos de prova 111In (111Cd), 140La (140Ce) e 181Hf(181Ta). Estas propriedades foram complementadas por medidas de Magnetização.
This work describes, from an atomic point of view, the investigation of magnetic nanoparticles (MNPs) of magnetite (Fe3O4) and ferrites of the type TMFe2O4 (TM = Co, Ni), which are a class of structured materials that currently have a great interest due to the great variety of its possible technological and biomedical applications by Perturbed γ-γ Angular Correlation Spectroscopy (PAC). Two chemical routes were used to produce MNPs: the co-precipitation method and the thermal decomposition method. Co-precipitation has the advantages of having moderate temperatures and relatively low costs, but particle size distribution control is not achieved. On the other hand, the thermal decomposition allows a monodisperse sample with size and shape control, but this method requires toxic reagents, expensive and high reaction temperature. The X-Ray Diffraction (XRD) technique was used to characterize the samples and the morphology of the NPs was studied by Electron Transmission Electron Microscopy (TEM). From this technique it was possible to evaluate grain size distribution, because some characteristics such as high magnetization value, high anisotropy and a high coercivity value are properties that depend on the nanostructures. The magnetic properties were studied locally from the Perturbed Angular Correlation (CAP), which uses as probe nuclei of the measurements, such as 111In (111Cd), 140La (140Ce) and 181Hf (181Ta). These properties were complemented by Magnetization measurements.

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Ballesteros, Camilo Arturo Suarez. "Síntese e caracterização de nanopartículas Fe3O4@Au e desenvolvimento de sensores para aplicações em nanomedicina". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-23102012-101205/.

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Com o desenvolvimento de novos nanomateriais têm-se descoberto propriedades eletrônicas, elétricas, ópticas e catalíticas únicas para aplicações nanotecnológicas. Entre estes nanomateriais com caraterísticas singulares, estão as nanopartículas (Np) CoreαShell, as quais combinam propriedades físico-químicas de dois materiais diferentes, provendo maior eficiência em aplicações como nanoeletrônica, sensoreamento, biossensoreamento e biomédicas. Neste trabalho, Np CoreαShell são sintetizada com núcleo (Core) de Np Fe₃O₄ e com casca (Shell) de Np Au, formando as Nps Fe₃O₄αAu na presença do dendrímero poli(amidoamina) geração 4.0 (Pamam G4). As propriedades físico-químicas do nanomaterial core-shell são estudadas através de análises espectroscópicas, microscopias e eletroquímicas, além de medidas de magnetização. Essas técnicas revelam a formação das Nps Au nas cavidades do Pamam G4 e as interações eletrostáticas entre os grupos funcionais do Pamam G4 e os grupos OH ⁻ e H ⁺ da superfície das Nps magnéticas, as quais dão uma forte estabilidade na configuração da Np Fe₃O₄αAu. Evidencia-se propriedades óticas da Np Au e propriedades superparamagnéticas da Np Fe ₃ O ₄, as quais podem ser usadas para aplicações em nanomedicina. As propriedades electrocatalíticas das Nps são utilizadas na detecção de dopamina (DA). Foram fabricados sensores eletroquímicos das Nps Fe₃O₄αAu, Nps Fe₃O₄ e Nps Au, e caracterizados por técnicas de voltametria cíclica e voltametria de pulso diferencial. A fabricação dos sensores consistiu na deposição de camadas alternadas entre as nanopartículas com o poliânion poly(ácido vinil sulfônico) (PVS) no eletrodo de ITO, levando à configuração de três arquiteturas; ITO - (Fe₃O₄αAu ⁄ PV S), ITO - (Fe₃O₄ ⁄ PV S) e ITO - (Au ⁄ PV S). Um problema encontrado na detecção de DA é que esta tem potenciais de oxidação aproximadamente iguais ao ácido ascórbico (AA) e ao ácido úrico (AU). Portanto, os sensores utilizados na detecção de DA, devem ser altamente seletivos a DA em relação a seus interferentes. Os sensores desenvolvidos aqui mostraram uma boa seletividade e velocidade de resposta na detecção de DA, sendo o sensor ITO - (Fe₃O₄αAu ⁄ PV S) o mais eficiente. As Nps Fe₃O₄αAu revelam maior citotoxicidade nas células cancerígenas comparadas com as células saudáveis, já que as células cancerígenas são mais sensíveis ao estresse oxidativo produzido pelas nanopartículas no interior da célula.
Along with the development of nanomaterials came the knowledge and design of their unique eletronic, optical and catalitycal properties which may be used for a variety of nanotecnological applications. A special class of nanomaterials with interesting characteristics is represented by the CoreαShell nanoparticles, which combine the physicochemical properties of two differerent nanomaterials (including oxides, metals, semiconductors or polymers). This combination provides greater efficiency in applications such as nanoelectronics, sensing, biosensing and biomedical areas. This study reports the synthesis of Fe₃O₄ Np, which in the presence of the polyamido amine generation 4.0 (Pamam G4), is covered with Au Np forming the Fe₃O₄αAu Nps. The nanomaterials had been characterized using spectroscopic, microscopic and electrochemical techniques. The results revealed the formation of Au Nps in the cavities of PAMAM G4 and showed that the electrostatic interactions between the PAMAM functional groups and the OH ⁻ and H ⁺ groups on the surface of the magnetic nanoparticles lead to a strong stability in the configuration of Fe₃O₄αAu Nps. The optical properties of the Au Np (namely the Plasmon resonance band at 542 nm) as well as the superparamagnetic properties of the Fe₃O₄ Np were present in the core-shell nanostrutures. Due to their electrocatalytical properties, the core-shell nanoparticles were employed as active elements for dopamine (DA) detection. The fabrication of the modified electrodes for DA detection consisted in the deposition by LbL technique of alternating layers of nanoparticles and poly(vinyl sulfonic acid) (PVS) on the ITO eletrode, in three distinct architectures: ITO - (Fe₃O₄αAu Fe₃O₄ PV S), ITO - (Fe₃O₄ ⁄ PV S) and ITO - (Au ⁄ PV S). We found a good selectivity and rapid response toward the detection of DA, being the sensor ITO - (Fe₃O₄αAu ⁄ PV S) the most efficient. The effect of Fe₃O₄αAu Nps showed a higher cytotoxicity in cancer cells compared to healthy cells, because cancer cells are more sensitive to oxidative stress produced by the nanoparticles.

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Rodrigues, Marcos Renan Flores. "Estudo e caracterização de nanopartículas de Fe3O4, Fe2O3, Fe3O4/ Aunanop E Fe2O3/Aunanop". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/184573.

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Nanopartículas de Fe3O4 e Fe2O3 foram sintetizadas a partir da rota de coprecipitação, em atmosfera de N2, mantendo-se o pH entre 9 e 14 na temperatura ambiente e utilizando como precursores o FeCl2 e FeCl3. Após a síntese, as nanopartículas foram tratadas termicamente a 250, 500 e 800 oC. Para obtenção de um sistema híbrido, foram sintetizadas nanopartículas de ouro sobre as nanopartículas de óxido previamente tratadas em diferentes temperaturas. As amostras foram caracterizadas por UV-Vis, difratometria de Raios-X (DRX), microscopia eletrônica de transmissão (MET), microscopia eletrônica de transmissão de alta resolução (MET-AR), espectroscopia no na região do infravermelho (FTIR), magnometria de amostra vibrante (VSM) e espectroscopia Mossbauer (EM), e aplicadas para produção de hidrogênio promovendo a decomposição da hidrazina. Os resultados mostram a síntese de nanopartículas de óxido de ferro com diâmetro médio de cerca de 7 nm. Quando aquecidas a 250 oC o tamanho médio aumentou para ca. de 11 nm e foi observado uma pequena mudança no comportamento óptico e estrutural, mantendo o comportamento superparamagnetico. Quando aquecidas a 500 oC o tamanho médio aumenta para ca. de 50nm e são observadas mudanças significativas nas propriedades ópticas, morfológicas, estruturais. Adicionalmente observa-se transição de comportamento superparamagnetico para paramagnético. Quando aquecidas a 800 oC os efeitos nas propriedades dos materiais são ainda mais significativos; as partículas apresentam tamanho médio de 200 nm, o espectro de absorção no UV-Vis muda significativamente e as partículas passam a ter comportamento pagamagnético. Os resultados obtidos pelas diferentes técnicas e somadas ao Mossbauer sugerem que as amostras sintetizadas são uma mistura de Fe3O4 e -Fe2O3, quando aquecido a 250 e 500 oC uma mistura de -Fe2O3 e -Fe2O3 e a 800 oC somente -Fe2O3. As nanopartículas de ouro sintetizadas sobre as amostras de oxido de ferro apresentaram tamanho médio de 6,0 nm e não afetaram as propriedades magnéticas dos oxidos. As amostras de óxido com nanopartículas de ouro promoveram a decomposição da hidrazina por rota completa, levando a formação de hidrogênio com seletividade de até 33%.
Fe3O4 and Fe2O3 nanoparticles were synthesized by coprecipitation route carried out under N2 atmosphere, maintaining the pH between 9 and 14 at room temperature and using FeCl2 and FeCl3 as precursors. After synthesis the iron oxide nanoparticles were thermally treated at 250, 500 and 800 oC. To obtain a hybrid system, gold nanoparticles were synthesized on the thermally treated oxide nanoparticles. The samples were analyzed by UV-Vis, X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (MET-AR), spectroscopy in the region of Infrared (FTIR), vibrating sample magnitude (VSM) and Mossbauer, and applied to produce H2 through hydrazine decomposition. The results show the synthesis of Fe3O4 nanoparticles with average diameter of about 7 nm. When heated to 250 oC the average size increased to about 11 nm and a small change in the optical and structural behavior was observed, while the superparamegnetic behaviour was maintained. When heated to 500 °C, the average particle size increase to ca 51nm, significant changes in the optical, morphological and structural properties are observed, in addition to a transition from superparamegnetic to paramagnetic behaviour. When heated to 800 oC the effects on the properties are even more significant; the nanoparticles increase to ca. 200 nm, the absorption spectrum in UV-Vis changes significantly and the particles present paramagnetic behaviour. The results suggest that when heated to 250 and 500 oC a mixture of -Fe2O3 e -Fe2O3 is obtained, after heating at 800 oC only -Fe2O3 is observed. The gold nanoparticles synthesized on the iron oxides present average size of 6.0 nm, and did not affect the magnetic properties of the oxides. The iron oxides/gold nanoparticle samples were efficiently applied to produce hydrogen, promoting the decomposition of hydrazin. The selectivity to hydrogen reached up to 33%.

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Nunes, Eloiza da Silva [UNESP]. "Preparação e caracterização de nanocompósitos de Fe@SiO2, Fe@Fe3O4 e Fe3O4@PNIPAM". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/124538.

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Neste trabalho foi investigada a obtenção de nanopartículas de ferro metálico em diferentes meios não aquosos (glicóis) e em água através da rota de redução com boroidreto e a obtenção de estruturas caroço@casca Fe@SiO2 e Fe@Fe3O4. Também são apresentados resultados da caracterização de nanocompósitos magnéticos à base poli(N-isopropilacrilamida) (PNIPAM) e de nanogéis poliméricos (controles) através do método de polimerização radicalar por precipitação. A composição dos nanocompósitos poliméricos foi variada quanto ao tipo de co-monômero (ácido acrílico e poli(etileno glicol) metiléter metacrilato (PEGMA)), reticulador (metileno bis-acrilamida (MBA) e poli(etileno glicol) diacrilato (PEGDA)) e nanopartícula magnética precursora. As nanopartículas metálicas e nanoestruturas Fe@SiO2 e Fe@Fe3O4 foram caracterizadas por DRX, espectroscopia Mössbauer, XPS, SEM e TEM. Os resultados obtidos demostraram que as nanopartículas de ferro metálico foram compostas de α-Fe e variáveis teores de liga de Fe1-xBx e a morfologia e tamanho de partícula variaram em função dos diferentes meios reacionais empregados. As metodologias de recobrimento das partículas metálicas precursoras foram eficazes na estabilização química do caroço magnético. O recobrimento com sílica para obtenção das estruturas Fe@SiO2 foi realizado empregando-se precursores alcoxissilanos através do processo sol-gel. A espessura da camada de sílica pode ser controlada mais eficientemente no caso de partículas maiores oriundas de redução no meio aquoso e no caso de nanopartículas pequenas observou-se a formação de agregados. As estruturas Fe@Fe3O4 foram obtidas pela passivação das nanopartículas metálicas em solvente glicol. A metodologia de passivação demostrou a possiblidade de oxidação controlada da superfície para fase de magnetita evitando a formação de óxi-hidróxidos não...
In this work the obtainment of metallic iron nanoparticles in several non-aqueous (glycols) and in aqueous media through chemical reduction with sodium borohydride and the obtainment of core@shell structures Fe@SiO2 and Fe@Fe3O4, was investigated. The characterization results of poly(N-isoproprylacrylamide) (PNIPAM) based magnetic nanocomposites and bare polymeric nanogels (controls) synthesized through radical precipitation polymerization were also presented. The composition of the polymeric nanocomposites was varied as the type of co-monomer (acrylic acid and poly(ethyleneglycol) methylether methacrylate (PEGMA)), crosslinker (methylene bis-acrylamide (MBA) and poly(ethyleneglycol) diacrylate (PEGDA)) and precursor magnetic nanoparticle. The metallic nanoparticles and the core@shell Fe@SiO2 and Fe@Fe3O4 nanostructures were characterized by XRD, Mössbauer spectroscopy, XPS, SEM and TEM. The results show that the iron nanoparticles were composed of α-Fe and varying amounts of Fe1-xBx alloy and the size and morphology of the particles was dependent of the reaction media used. The strategies for metallic nanoparticles coating was efficient and chemically stabilized the magnetic cores. The Fe@SiO2 nanostructures was prepared by using alkoxysilanes precursors through the sol-gel process to produce the silica coating. The silica thickness could be controlled more efficiently in the case of bigger particles produced from chemical reduction in aqueous media. In the case of small nanoparticles the formation of aggregates was observed. The Fe@Fe3O4 core@shell structures were obtained by passivation of the metallic iron nanoparticles in a glycol solvent. The method of passivation enabled good oxidation control of the metallic surface to magnetite phase, avoiding the formation of non-magnetic oxy-hydroxides. The metallic to oxide phase ratio was determined by Rietveld refinement and was dependent of the type...

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Cláudia, Vaz de Araújo Ana. "Síntese de nanopartículas de Fe3O4, nanocompósitos de Fe3O4 com polímeros e materiais carbonáceos". Universidade Federal de Pernambuco, 2011. https://repositorio.ufpe.br/handle/123456789/9226.

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Universidade Federal Rural de Pernambuco
Nanopartículas magnéticas de Fe3O4 foram sintetizadas através do método da precipitação a partir de uma solução aquosa de sulfato ferroso, sob ultrassom. Um planejamento fatorial 23 em duplicata foi desenvolvido para determinar as melhores condições de síntese e obter o menor tamanho de cristalito. As condições selecionadas foram: freqüência do ultrassom de 593 kHz durante 40 min em 1,0 mol L-1 de hidróxido de sódio. Foi obtido tamanho médio do cristalito da ordem de 25 nm. A fase cristalina obtida foi identificada por difratometria de raios-X (DRX) como sendo a magnetita. A microscopia eletrônica de varredura (MEV) mostrou partículas polidispersas com dimensões em torno de 57 nm, enquanto a microscopia eletrônica de transmissão (MET) revelou um diâmetro médio das partículas em torno de 29 nm, na mesma ordem de grandeza do tamanho de cristalito determinado com a equação de Scherrer. Estas nanopartículas magnéticas foram utilizadas para a obtenção de nanocompósitos com polianilina (PAni). O material foi preparado sob exposição à luz ultravioleta (UV) ou sob aquecimento, a partir de dispersões das nanopartículas em solução ácida de anilina. Ao contrário de outras rotas sintéticas reportadas na literatura, esta nova rota não faz uso de um agente oxidante adicional. Análises de DRX mostraram o surgimento de uma segunda fase cristalina em todos os compósitos de PAni-Fe3O4, a qual foi indexada como goetita. Além disso, o tamanho de cristalito diminui quase 50% em função do aumento do tempo de síntese. Esta diminuição de tamanho sugere que as nanopartículas são consumidas durante a síntese. A análise termogravimétrica mostrou que a quantidade de polianilina aumenta com o aumento do tempo de síntese. A condutividade elétrica dos nanocompósitos foi de cerca de 10-5 S cm-1, aproximadamente uma ordem de grandeza mais alta que para a magnetita pura. A condutividade variou com a quantidade de PAni presente no sistema, sugerindo que as propriedades elétricas dos nanocompósitos podem ser ajustadas de acordo com a sua composição. Sob a aplicação de um campo magnético externo os nanocompósitos apresentam histerese a temperatura ambiente, característica de materiais ferromagnéticos. A magnetização de saturação (MS) observada para a magnetita pura foi cerca de 74 emu/g. Para os nanocompósitos PAni-Fe3O4, MS variou de aproximadamente 2,0 a 70 emu/g de acordo com as condições de síntese. Isto sugere que a composição do material também pode ser usada para controlar suas propriedades magnéticas. Um nanocompósito de PAni-Fe3O4-Quitosana foi obtido a partir de uma mistura das nanopartículas de Fe3O4 com uma solução de anilina e uma solução ácida de quitosana exposta à UV. O uso da quitosana permitiu a obtenção de filmes contendo PAni e nanopartículas de Fe3O4, as quais apresentaram diâmetro médio da ordem de 5 nm. A ausência de histerese nas medidas de magnetização indicou que o material possui características superparamagnéticas. A pirólise de misturas de PAni sintetizada quimicamente e nanopartículas de Fe3O4 foi utilizada para produzir materiais carbonáceos porosos. Morfologias fibrilares foram observadas por MEV e MET. Resultados mostraram que o material é mesoporoso (diâmetro de poro de 2 a 50 nm), com áreas superficiais de BET entre 200 e 400 m2/g

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Jesus, Ana Carla Batista de. "Síntese e caracterização de nanoestruturas Fe3O4 e Fe3O4@Ag para estudos com hipertermia magnética". Pós-Graduação em Física, 2018. http://ri.ufs.br/jspui/handle/riufs/8037.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Fundação de Apoio a Pesquisa e à Inovação Tecnológica do Estado de Sergipe - FAPITEC/SE
In this work we have performed a study of the structural and magnetic properties in Fe3o4@Agx nanostructures (x=0,1,5 and 10%), synthesized by thermal decomposition (DT) and co-precipitation (CP). The samples were characterized by measurements of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns indicate the presence of the Fe3o4 and Ag phase. The mean crystallites size corresponding to the Fe3o4 estimated by using the Scherrer’s equation shows that the nanostructures present not change considerable in the size after insertion of Ag for both growth methods. The TEM images obtained for DT samples reveal that the nanostructures are a like-spherical shape and average sizes of 3 nm which are in good according with size estimated by XRD. The mass loss observed in TG analysis was used to estimate the amount of organic matter present in the samples and consenquently normalize the magnetic measurements. The magnetic characterization was carried out by magnetization measurements as a function of magnetic field (MvsH) and temperature in Zero Field Cooling – Field Cooling (ZFC/FC) modes. These results indicate that the samples present superparamagnetic behavior to start 220 K. Fits of the ZFC / FC curves allowed verify that the magnetic anisotropy constant decreasing as a function of Ag-concentration. Magnetic hyperthermia measurements were performed in the samples synthesized via CP and the specific absorption rate (SAR) was estimated between 8 and 40 W / g.
Neste trabalho foi realizado um estudo das propriedades estruturais e magnéticas em nanoestruturas Fe3o4@Agx (x=0,1,5 and 10%), sintetizadas pelos métodos de decomposição térmica (DT) e de co-precipitação (CP). As amostras foram caracterizadas estruturalmente através de medidas de difração de raios X (DRX) e microscopia eletrônica de transmissão (MET). Os padrões de DRX indicam a presença da fase cristalina de Fe3o4 para todas as amostras, mas nas amostras aonde foi inserida a Ag há presença de uma outra fase cristalina, ou seja, a fase da Ag. O tamanho médio dos cristalitos estimados utilizando a largura à meia altura dos picos de DRX e a equação de Scherrer, mostra que as nanoestruturas não sofreram alterações consideráveis de tamanho após o acréscimo da Ag, mesmo com o aumento da concentração de Ag para ambos os métodos. As imagens de MET obtidas para as amostras sintetizadas via DT revelam que as nanoestruturas apresentam formatos praticamente esféricos e com tamanhos médios de 3 nm, que estão de acordo com os tamanhos estimados por DRX. Análises termogravimétricas foram utilizadas para estimar as perdas de massa de orgânicos presente nas amostras e assim realizar a normalização das medidas de magnetização. A caracterização magnética foi feita através de medidas de magnetização em função do campo magnético (MvsH) e da temperatura no modo Zero Field Cooling – Field Cooling (ZFC/FC). Estas medidas indicam que as amostras apresentam um comportamento superparamagnético a partir de 220 K. A realização de ajustes nas curvas ZFC/FC permitiu verificar que a constante de anisotropia magnética diminui com a concentração de Ag. Também foram realizadas medidas de hipertermia magnética nas amostras sintetizadas via CP e através das análises foi estimada a taxa de absorção específica (SAR), com valores entre 8 e 40 W/g.
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Libros sobre el tema "FePO4"

Goulding, Harold B. Yasmé: Some random collections of a former FEPOW. London: People's Publications, 1988.

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Fepow: The story of a voyage beyond belief. London: Hale, 1985.

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Kelly, Terence. Fepow: The story of a voyage beyond belief. Hale, 1985.

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Walker, J. Of Rice and Men. Lane Publishers, 1999.

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Núñez Lira, Luis Alberto. Participación ciudadana, mito y realidad una aproximación teórica. 2^a ed. Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.1.

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Cuando nos dispusimos a realizar esta investigación, nuestro horizonte estaba enmarcado en demostrar que la participación ciudadana en el pro- ceso de gobernabilidad era el punto central de la gobernanza en el país. Sin embargo, al ingresar al enorme mundo de este tema, encontramos una referencia bibliográfica y material primario inmenso, que nos lleva a creer que solo estamos viendo el iceberg de la complejidad del problema.

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Diaz Dumont, Jorge Rafael. Tecnología de información y comunicación teoría y filosofía. 2^a ed. Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.2.

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En el campo educativo, el uso de Internet ha permitido impartir cursos a distancia, convirtiéndose en una importante opción y solución, de formación y actualización, para que la población pueda insertarse en el ámbito laboral de la sociedad tan cambiante que nos ha tocado vivir y que ha dado en denominarse “sociedad de la información", “sociedad digital”, “sociedad del conocimiento” y “sociedad red”.

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Quiroz Quiroz, Enrique y Florencio Flores Ccanto. Significado de la Potenciación en ℝ. Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.3.

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El recojo de las prácticas matemáticas sobre la potenciación, los diferentes autores definen, primero la potencia de base real y exponente natural. Su significado no es otro que un producto repetido, excepto para exponentes 0 y 1. Algunos autores establecen que 〖-3〗^4 no es una potencia, sino el opuesto de la potencia 3^4. También ambiguo al decir que 0^0 es una expresión indeterminada o que existe radicales de números negativos como ∛(-8). Después de resolver las representaciones y definiciones ambiguas se deja camino abierto para formular el significado institucional. Se describe el significado de la potencia de base real y exponente natural mostrando que se trata de un producto repetido, excepto para 1 y 0. Para la definición de la potencia con exponente fraccionario primero se describe el significado del denominador n del exponente fraccionario m/n. Además, se demuestra que el exponente fraccionario será cualquier fracción equivalente a m/n, pues de lo contrario será una definición ambigua, que es origen de algunas prácticas matemáticas erróneas. Teniendo en cuenta los argumentamos de tres prácticas matemáticas erróneas. Se refiere a la representación y significado de potencia de base real y exponente negativo como 〖-a〗^n=-(a^n ),a∈R, esta expresión solo es cierta si n es impar. Luego, se prueba que utilizar radicales de índice impar de números negativos como ∛(-8) , √(5&-32) nos conducen a situaciones paradójicas como a=-a,∀a∈R. Finalmente mostramos que 0^0 es 1.

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Garcia Curo, Gianmarco y Erika Mirella Gutiérrez Sullca. Sistema interactivo para el aprendizaje del idioma inglés en personas con deficiencia visual. Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.4.

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El presente manuscrito se planteó determinar la influencia de un sistema interactivo con retroalimentación auditiva en el aprendizaje del idioma inglés en personas con deficiencia visual, formulando la siguiente hipótesis: El sistema interactivo con retroalimentación auditiva influye positivamente en el aprendizaje del idioma inglés de personas con deficiencia visual. Para desarrollar la investigación se enmarcó en el método científico, tipo de investigación aplicada en el nivel explicativo y el diseño Pre experimental (G: O1 – X – O2). La implementación se realizó con una muestra total de 24 personas con diversos grados de deficiencia visual. Realizadas las pruebas pre y post, se evidenció que el uso del sistema interactivo con retroalimentación auditiva si influye positivamente en al aprendizaje del idioma inglés, al realizar una comparación en el desempeño de la muestra referente a su habilidad de escuchar inglés el resultado fue de un 24.54% de aprobados en pre test y un 56.48% de aprobados en el post test, logrando una mejora del 31.94% confirmando la hipótesis general, por otro lado en la habilidad de hablar inglés el resultado fue de un 15.15% de aprobados en el pre test y un 53.79% de aprobados en el post test logrando una mejora del 38.64%, también validando la hipótesis general.

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Garcia Curo, Gianmarco. Certificación Digital con QR. Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.6.

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La certificación le atribuye a un usuario haber cumplido una designación, curso o haber culminado satisfactoriamente una determinada actividad; sin embargo, a lo largo de los años su versión física está siendo desplazada por los certificados digitales, posicionándose una excelente alternativa. La certificación digital por sí misma debe contar con identificadores que permitan verificar su originalidad; sin embargo, incrustarle la verificación QR le da un valor agregado, el acceso con este tipo de identificador simplifica el proceso de verificación de originalidad, ya que se puede acceder desde cualquier equipo con lectora QR. El sistema de emisión de certificados digitales es un sistema web, dadas sus características de accesibilidad, para su desarrollo son necesarias un conjunto de herramientas y la aplicación de una metodología para garantizar el cumplimiento de requerimientos que una entidad establezca para su propio sistema de emisión de certificados. Regular la emisión de certificados es importante, la gran cantidad de entes proveedores permite una tasa mayor de falsificaciones, por ello en el Perú se promulgó la Ley y Reglamento de Firmas y Certificados Digitales que tiene por objetivo garantizar la autenticación y a su vez la integridad de los certificados digitales.

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Diaz Dumont, Jorge Rafael. Escala de valoración para entornos virtuales de aprendizaje (EVA). Fondo Editorial Professionals On Line, 2022. http://dx.doi.org/10.47422/fepol.5.

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La presente publicación tiene como fin dar a conocer y validar un instrumento que permita medir el uso que tienen los Entornos Virtuales de Aprendizaje para los usuarios que interactúan con estas “Plataforma Virtuales”, conocidos igualmente por su abreviatura “LMS” (Sistema de Gestión del Aprendizaje), que son concretamente programas de computadoras que se utilizan para la creación, gestión y distribución de actividades formativas a través de la Web; son aplicaciones que facilitan la creación de entornos de enseñanza-aprendizaje, integrando materiales didácticos, herramientas de comunicación, colaboración y gestión educativa. En este contexto es importante indicar que la presente publicación recopila información contenida en la Tesis Doctoral del mismo autor sustentada el 30 de marzo del año 2015 en Lima Perú y publicada posteriormente el Alemania Siendo así, esta publicación toma como referencia la referida Tesis Doctoral del mismo autor que se encuentra en la Biblioteca Nacional Alemana (DNB)

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Harisch, Günther y Michael Kretschmer. "Ferrum phosphoricum (Eisenphosphat, FePO4)". En Jenseits vom Milligramm, 91–102. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-47595-5_6.

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Hashizume, Takashi, Atsushi Saiki y Kiyoshi Terayama. "Solid Reaction Mechanism of Li2 CO3 and FePO4 /C Powder". En Ceramic Transactions Series, 93–102. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118771464.ch9.

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Khan, F. B., K. Bharuth-Ram y H. B. Friedrich. "Phase transformations of the FePO4 catalyst in the oxidative dehydrogenation to form an alkyl methacrylate". En HFI / NQI 2010, 317–23. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-94-007-1269-0_52.

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Villars, P., K. Cenzual, J. Daams, R. Gladyshevskii, O. Shcherban, V. Dubenskyy, N. Melnichenko-Koblyuk et al. "Fe3O4". En Structure Types. Part 5: Space Groups (173) P63 - (166) R-3m, 668. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-46933-9_542.

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Vaneeckhaute, Céline, Joery Janda, Erik Meers y F. M. G. Tack. "Efficiency of Soil and Fertilizer Phosphorus Use in Time: A Comparison Between Recovered Struvite, FePO4-Sludge, Digestate, Animal Manure, and Synthetic Fertilizer". En Nutrient Use Efficiency: from Basics to Advances, 73–85. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-2169-2_6.

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Villars, P., K. Cenzual, J. Daams, R. Gladyshevskii, O. Shcherban, V. Dubenskyy, N. Melnichenko-Koblyuk et al. "(Eu0.5Yb0.5)Fe2O4". En Structure Types. Part 5: Space Groups (173) P63 - (166) R-3m, 549–50. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-46933-9_434.

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Holze, Rudolf. "Ionic conductance of FeSO4". En Electrochemistry, 889. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-49251-2_836.

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Wollschläger, J. "Coexistence of domains: other binary oxides (Ce7O11, Fe3O4, Fe3O4/MgO, SnO2, WO3)". En Physics of Solid Surfaces, 338–41. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-53908-8_76.

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Moarref, Roxana y Saeed Pourmahdian. "Preparation of Fe3O4/Polymethyl Methacrylate Composite Particles from Monolayer Oleic Acid-Modified Fe3O4". En Eco-friendly and Smart Polymer Systems, 371–74. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45085-4_89.

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Pylypchuk, Ie V., Iu P. Mukha, N. V. Vityuk, K. Szczepanowicz, L. P. Storozhuk, A. M. Eremenko, P. Warszyński y P. P. Gorbyk. "Tryptophan-Stabilized Plasmonic Fe3O4/Ag Nanoparticles". En Springer Proceedings in Physics, 417–30. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-17755-3_28.

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Actas de conferencias sobre el tema "FePO4"

Prosini, Pier Paolo, Cinzia Cento, Amedeo Masci, Maria Carewska y Paola Gislon. "A synthesis of LiFePO4 starting from FePO4 under reducing atmosphere". En PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON MATHEMATICAL SCIENCES. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4883049.

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Islam, Mujahidul, Adedamla Omole, Arif Islam y Alexander Domijan. "Dynamic capacity estimation for a typical grid-tied event programmable Li-FePO4 battery". En 2010 IEEE International Energy Conference (ENERGYCON 2010). IEEE, 2010. http://dx.doi.org/10.1109/energycon.2010.5771751.

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Sanchez, Luciano, Ines Couso y Cecilio Blanco. "Online SOC estimation of Li-FePO4 batteries through an observer of the system state with minimal nonspecificity". En 2015 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE). IEEE, 2015. http://dx.doi.org/10.1109/fuzz-ieee.2015.7337901.

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Zhang, Bao, Jiafeng Zhang, Chao Shen, Chunli Peng y Qian Lian. "Effects of reaction conditions on preparation of FePO4·2H2O and properties of LiFePO4 by solution precipitation route". En 2010 IEEE 3rd International Nanoelectronics Conference (INEC). IEEE, 2010. http://dx.doi.org/10.1109/inec.2010.5424913.

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Tanboonjit, Bundit y Nisai H. Fuengwarodsakul. "Implementation of charger and battery management system for fast charging technique of Li-FePO4 battery in electric bicycles". En 2014 Ninth International Conference on Ecological Vehicles and Renewable Energies (EVER). IEEE, 2014. http://dx.doi.org/10.1109/ever.2014.6844103.

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Ma, XiaoLing, Yejun Zhao y Youxiang Zhang. "Effect of reaction time on the FePO4 synthesized for the LiFePO4/C cathode material of lithium ion batteries". En 4th International Conference on Computer, Mechatronics, Control and Electronic Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/iccmcee-15.2015.128.

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Carkit, Taner. "Using Artificial Bee Colony and Dragonfly Algorithms to Improve the Accuracy of Parameter Estimation of Li- FePO4 Battery Cell". En 2022 Global Energy Conference (GEC). IEEE, 2022. http://dx.doi.org/10.1109/gec55014.2022.9987189.

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Sanchez, Luciano, Ines Couso y Juan Carlos Viera. "Online SOC Estimation of Li-FePO4 Batteries through a New Fuzzy Rule-Based Recursive Filter with Feedback of the Heat Flow Rate". En 2014 IEEE Vehicle Power and Propulsion Conference (VPPC). IEEE, 2014. http://dx.doi.org/10.1109/vppc.2014.7007113.

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Huang, Z., J. Yue, J. Wang, Y. Zhai, Y. Xu y B. Wang. "Oscillatory tunneling magnetoresistance in Fe3O4/GaAs/Fe3O4 junction". En 2015 IEEE International Magnetics Conference (INTERMAG). IEEE, 2015. http://dx.doi.org/10.1109/intmag.2015.7156969.

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Albano, Carmen, Gema Gonzalez y Claudio Naranjo. "PLLA- Fe3O4 nanocomposites". En 6TH INTERNATIONAL CONFERENCE ON TIMES OF POLYMERS (TOP) AND COMPOSITES. AIP, 2012. http://dx.doi.org/10.1063/1.4738455.

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Informes sobre el tema "FePO4"

S.E. Ziemniak y R.A. Castelli. Immiscibility in the Fe3O4-FeCr2O4 Spinel Binary. Office of Scientific and Technical Information (OSTI), marzo de 2003. http://dx.doi.org/10.2172/821371.

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Toney, Michael F. Nanoscale Phase Separation in Fe3O4(111) Films on Sapphire(0001) and Phase Stability of Fe3O4(001) Films on MgO(001) Grown by Oxygen-Plasma-Assisted Molecular Beam Epitaxy. Office of Scientific and Technical Information (OSTI), junio de 2003. http://dx.doi.org/10.2172/813273.

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Steven A. Attanasio, David S. Morton y Mark A. Ando. Measurement and Calculation of Electrochemical Potentials in Hydrogenated High Temperature Water, including an Evaluation of the Yttria-Stabilized Zirconia/Iron-Iron Oxide (Fe/Fe3O4) Probe as Reference Electrode. Office of Scientific and Technical Information (OSTI), octubre de 2001. http://dx.doi.org/10.2172/821313.

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