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Structural evolution and reaction mechanism of lithium nickelate(LiNiO_(2))during the carbonation reaction

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Journal of Materiomics 2018年第1期4卷 56-61页

作者： Daniela Gonzalez-Varela Brenda Alcantar-Vazquez heriberto pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autonoma de MexicoCircuito exterior s/nCUDel.CoyoacanCP 04510Ciudad de MexicoMexico Instituto de Ingenieria Coordinacion de Ingeniería AmbientalUniversidad Nacional Autonoma de MexicoCircuito Escolar s/nCUDel.CoyoacanCP 04510Ciudad de MexicoMexico

Lithium nickelate(LiNiO_(2))was synthesized using the lithium excess method,and then characterized by X-ray diffraction,scanning electron microscopy and N_(2) ***,differential thermal and thermogravimetric analyses were performed in CO_(2)presence,at high *** show that LiNiO_(2)is able to react with CO_(2)through a complex structural evolution process,where lithium atoms are released to produce Li_(2)CO_(3),while some nickel atoms are rearranged on different Li_(1-x)Ni_(1+x)O_(2)crystalline ***_(2)-CO_(2)reaction kinetic parameters were determined assuming a first-order reaction,where kinetic constants tended to increase as a function of ***,kinetic constant values did not follow a linear *** atypical behavior was attributed to LiNiO_(2)sintering and crystalline evolution performed as a function of temperature.

关键词： Lithium nickelate CO_(2)chemisorption Lithium diffusion coefficient Phase transition

High CO_(2)permeation using a new Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)composite ceramic–carbonate dual-phase membrane

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Journal of Environmental Sciences 2024年第6期140卷 219-229页

作者： Daniela González-Varela JFrancisco Gómez-García Gustavo Tavizon heriberto pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico Departamento de Física y Química Teórica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoCd.UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMéxico 不详

This work shows the synthesis,characterization and evaluation of dense-ceramic membranes made of Ce_(0.85)Gd_(0.15)O_(2-δ)-LaNiO_(3)(CG-LN)composites,where the fluorite-perovskite ratio(CG:LN)was varied as follows:75:25,80:20 and 85:15 wt.%.Supports were initially characterized by XRD,SEM and electrical conductivity(using vacuum and oxygen atmospheres),to determine the composition,microstructural and ionic-electronic conductivity ***,supports were infiltrated with an eutectic carbonates mixture,producing the corresponding dense dual-phase membranes,in which CO_(2)permeation tests were ***,CO_(2)permeation experiments were performed from 900 to 700℃,in the presence and absence of oxygen(flowed in the sweep membrane side).Results showed that these composites possess high CO_(2)permeation properties,where the O_(2)addition significantly improves the ionic conduction on the sweep membrane ***,the GC80-LN20 composition presented the best results due to the following physicochemical characteristics:high electronic and ionic conductivity,appropriate porosity,interconnected porous channels,as well as thermal and chemical stabilities between the composite support and carbonate phases.

关键词： CO_(2)permeation Doped CeO_(2) LaNiO_(3) Impedance Ceramic carbonate membrane

Synthesis of advanced ceramics by hydrothermal crystallization and modified related methods

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Journal of Advanced Ceramics 2012年第3期1卷 204-220页

作者： JoséORTIZ-LANDEROS Carlos GÓMEZ-YÁÑEZ Rigoberto LÓPEZ-JUÁREZ Iván DÁVALOS-VELASCO heriberto pfeiffer Departamento de Ingeniería Metalúrgica Escuela Superior de Ingeniería Química e Industrias ExtractivasIPNUPALMAv.Instituto Politécnico Nacional s/nCP 07738México DFMéxico. Centro de Ciencias Aplicadas y Desarrollo Tecnológico Universidad Nacional Autónoma de MéxicoA.P.70-186CoyoacánMéxico D.F.México. Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510México DFMéxico.

The present article aims to give a brief overview about the advantages of the hydrothermal crystallization method for the synthesis of advanced *** is given,not only on the conventional hydrothermal crystallization,but also on some of its variants;such as ultrasound-assisted,electrochemical-assisted,microwave-assisted and surfactant-assisted hydrothermal methods which open up new opportunities for the synthesis of ceramic materials with novel properties demanded for advanced *** the current work the synthesis of barium titanate(BaTiO3),lithium metasilicate(Li2SiO3)and sodium-potassium niobate(Na,K)NbO3 powders are reported as cases of study.

关键词： hydrothermal synthesis barium titanate Li_(2)SiO_(3) potassium-sodium niobate

Synthesis and evaluation as CO2 chemisorbent of the Li5(Al1-xFex)O4 solid solution materials:Effect of oxygen addition

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Journal of Energy Chemistry 2017年第5期26卷 948-955页

作者： Paulina Olavarría Elizabeth Vera Enrique J.Lima heriberto pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autońoma de MexicoCircuito exterior s/nCd.UniversitariaDel.Coyoacan C.P.04510Ciudad de MéxicoMexico

Pentalithium aluminate（β-LiAlO） and the corresponding iron-containing solid solution(Li(AlFe)O)were synthetized by solid-state reaction. All the samples were characterized structural and microstructurally by X-ray diffraction, solid-state nuclear magnetic resonance, scanning electron microscopy, Nadsorption-desorption and temperature-programmed desorption of CO. Results showed that 30 mol% of iron can be incorporated into the β-LiAlOcrystalline structure at aluminum positions. Moreover, iron addition induced morphological and superficial reactivity variations. Li(AlFe)Osamples chemisorbed CObetween 200 and 700 °C, where the superficial chemisorption presented the highest enhancement,in comparison to β-LiAlO. Additionally, Li(AlFe)Osamples sintered at higher temperatures thanβ-LiAlO. Isothermal COchemisorption experiments of β-LiAlOand Li(AlFe)Owere fitted to a first order reaction model, corroborating that iron enhances the COchemisorption, kinetically. When oxygen was added to the gas flow, COchemisorption process was mainly enhanced between 400 and 600 °C for the Li(AlFe)Osample in comparison to β-LiAlO. Hence, Li(AlFe)Osolid solution presented an enhanced COchemisorption process, in the presence and absence of oxygen, in comparison to β-LiAlO.

关键词： Lithium aluminate CO2 chemisorption Solid solution Thermogravimetry

NiO-CaO materials as promising catalysts for hydrogen production through carbon dioxide capture and subsequent dry methane reforming

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Journal of Energy Chemistry 2017年第5期26卷 942-947页

作者： Alejandra Cruz-Hernández J.Arturo Mendoza-Nieto heriberto pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMexico

In this work, CaO-NiO mixed oxide powders were evaluated as consecutive CO;chemisorbents and catalytic materials for hydrogen production thought the CH;reforming process. Between the NiO impregnated CaO and CaO-NiO mechanical composite, the first one presented better chemical behaviors during the CO;capture and CH;reforming processes, obtaining syngas（H;+ CO） as final product. Results showed that syngas was produced at two different temperature ranges, between 400 and 600 °C and at T > 800 °C, where the first temperature range corresponds to the CH;reforming process but the second temperature range was attributed to a different catalytic reaction process: CH;partial oxidation. These results were confirmed through different isothermal and cyclic experiments as well as by XRD analysis of the final catalytic products, where the nickel reduction was evidenced. Moreover, when a CO-O;flow was used during the carbonation process a triple process was achieved:（i） CO oxidation,（ii） CO;chemisorption and（iii） CH;reforming. Using this gas flow the hydrogen production was always higher than that obtained with CO;.

关键词： Methane reforming CO2 capture Calcium oxide H2 production NiO supported

Thermokinetic and conductivity analyzes of the high CO2 chemisorption on Li5AlO4 and alkaline carbonate impregnated Li5AlO4 samples:Effects produced by the use of CO2 partial pressures and oxygen addition

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Journal of Energy Chemistry 2017年第5期26卷 919-926页

作者： Pedro Sánchez-Camacho J.Francisco Gómez-García heriberto pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autońoma de MexicoCircuito exterior s/nCd.UniversitariaDel.Coyoacan C.P.04510Ciudad de Me´xicoMexico

The effect of COpartial pressure was evaluated during the COchemisorption in penta lithium aluminate（LiAlO）, using different COand Opartial pressures in the presence or absence of alkaline carbonates. Results showed that using low PO（0.1） did not affect the kinetic and final COchemisorption process. Moreover, small additions of oxygen（PO= 0.05） into the mixture flue gas, seemed to increase the COchemisorption. Additionally, the presence of alkaline carbonates modified the COcapture temperature range. COchemisorption kinetic parameters were determined assuming a double exponential model where direct COchemisorption and COchemisorption controlled by diffusion processes are ***, ionic diffusion was analyzed by ionic conduction analysis, where all the gravimetric and ionic measurements were in good agreement showing different diffusion processes depending on ***, the oxygen and alkaline carbonate additions have positive effects during the COchemisorption process in LiAlO, and a possible reaction mechanism is presented.

关键词： CO2 capture Thermogravimetric analysis Partial pressure Ionic conduction

Possible role of power-to-heat and power-to-gas as flexibleloads in German medium voltage networks

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Frontiers in Energy 2017年第2期11卷 135-145页

作者： Mark KUPRAT Martin BENDIG Klaus pfeiffer Forschungszentrum 3E LS EVH Siemens-Halske-Ring 13 03046Cottbus Germany

Germanys energy transition triggered a rapid and unilateral growth of renewable energy sources (RES) in the electricity sector. With increasing shares of intermittent RES, overcapacities during periods of strong wind and photovoltaic electricity generation occur. In the face of insufficient transmission capacities, due to an inhibited network extension, the electricity generation has to be curtailed. This curtailment of RES leads to economic losses and could be avoided through flexible loads. As an option to cope with those problems, the technologies of power-to-gas (PtG) and power-to-heat (PtH) are presented in this paper. First, the alkaline electrolyzer (AEL), polymer electrolyte membrane electrolyzer (PEMEL), and solid oxide electrolyzer cell (SOEC) are investigated regarding their operational parameters. Second, the electric boiler, electrode heating boiler, and heat pumps are considered. Ultimately, the network-supporting abilities and the potential to provide ancillary services, such as control power, load sequence operation, cold start and part load capability, are compared among one another.

关键词： power-to-gas power-to-heat flexible loads ancillary services coherent energy systems

Could non-invasive brain-stimulation prevent neuronal degeneration upon ion channel re-distribution and ion accumulation after demyelination?

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Neural Regeneration Research 2020年第11期15卷 1977-1980页

作者： Friederike pfeiffer Alia Benali Werner Reichardt Centre for Integrative Neuroscience(CIN) University of TubingenTubingenGermany Section for Computational Sensomotorics Department of Cognitive NeurologyHertie-Institute for Clinical Brain Research and Centre for Integrative NeuroscienceUniversity of TubingenTubingenGermany

Fast and efficient transmission of electrical signals in the nervous system is mediated through myelinated nerve *** neuronal diseases such as multiple sclerosis,the conduction properties of axons are disturbed by the removal of the myelin sheath,leaving nerve cells at a higher risk of *** some cases,the protective myelin sheath of axons can be rebuilt by remyelination through oligodendroglial *** any case,however,changes in the ion channel organization occur and may help to restore impulse conduction after *** the other hand,changes in ion channel distribution may increase the energy demand of axons,thereby increasing the probability of axonal *** attempts have been made or discussed in recent years to increase remyelination of affected axons in demyelinating diseases such as multiple *** approaches range from pharmacological treatments that reduce inflammatory processes or block ion channels to the modulation of neuronal activity through electrical cortical ***,these treatments either affect the entire organism(pharmacological)or exert a very local effect(electrodes).Current results show that neuronal activity is a strong regulator of oligodendroglial *** bridge the gap between global and very local treatments,non-invasive transcranial magnetic stimulation could be *** magnetic stimulation is externally applied to brain areas and experiments with repetitive transcranial magnetic stimulation show that the neuronal activity can be modulated depending on the stimulation parameters in both humans and *** this review,we discuss the possibilities of influencing ion channel distribution and increasing neuronal activity by transcranial magnetic stimulation as well as the effect of this modulation on oligodendroglial cells and their capacity to remyelinate previously demyelinated *** the physiological mechanisms underlying the effects of transcrani

关键词： ion channel multiple sclerosis neuronal activity oligodendrocyte (re-)myelination repetitive transcranial magnetic stimulation transcranial magnetic stimulation

Men becoming fathers by injection were more often age intracytoplasmic sperm born small for gestational

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Asian Journal of Andrology 2017年第1期19卷 103-106页

作者： Susanne Liffner Mats Hammar Marie Bladh Elizabeth Nedstrand heriberto Rodriguez Martinez Gunilla Sydsjo Obstetrics and Gynecology Department of Clinical and Experimental Medicine Faculty of Medicine and Health Sciences Linkoping University SE-581 85 LinkopingSweden

Being born with nonoptimal birth characteristics decreases the chance of becoming a father. Urogenital malformations as well as metabolic syndrome are more common in men born small for gestational age （SGA） and could be contributing factors to the reduced fertility rate seen in these men. It could imply that men becoming fathers by assisted reproductive technology （ART） more often are born with low birth weight （LBW）, preterm, and/or SGA than men conceiving without treatment and also that men where intracytoplasmic sperm injection （ICSI） had to be performed more often are born with nonoptimal birth characteristics than men where conventional in vitro fertilization （IVF） successfully could be used. In this retrospective, case-control study using Swedish national registers, we compared the birth characteristics of 1206 men who have become fathers by ART with a control group consisting of age-matched men who became fathers without treatment. The differences in birth characteristics between men becoming fathers by IVF and ICSI were also assessed. For men becoming fathers by ART, OR of being born with LBW was 1.66 （95% CI = 1.17-2.36） compared with fathers who conceived without treatment. OR of being born prematurely was 1.32 （95% CI = 1.00-1.77）. Men becoming fathers via ICSI had a doubled increased likelihood of being born SGA compared with men who became fathers via IVF （OR = 2.12; 95% CI = 1.17-3.83）. In conclusion, we have found that men becoming fathers by ICSI treatments had more often been born SGA than men becoming fathers by conventional IVF.

关键词： infertility intracytoplasmic sperm injection in vitro fertilization low birth weight preterm small for gestational age