Relevant bibliographies by topics / Lanthanum chromite

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Lanthanum chromite'

Author: Grafiati
Published: 4 June 2021
Last updated: 2 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Lanthanum chromite.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Lanthanum chromite"

1

Corrêa, H. P. S., C. O. Paiva-Santos, L. F. Setz, L. G. Martinez, S. R. H. Mello-Castanho, and M. T. D. Orlando. "Crystal structure refinement of Co-doped lanthanum chromites." Powder Diffraction 23, S1 (March 2008): S18—S22. http://dx.doi.org/10.1154/1.2903501.

Full text
Abstract:
Results of crystal structure refinements and phase quantification for samples of Co-doped lanthanum chromites with nominal composition LaCr1−xCoxO3, for x=0.00, 0.10, 0.20, and 0.30, prepared by combustion synthesis are presented. The resulting powders were characterized by scanning electron microscopy and X-ray diffraction (XRD). The XRD patterns were obtained with Cu Kα radiation for non-doped lanthanum chromite sample and additionally with Cr Kα radiation for Co-doped lanthanum chromites samples, in order to enhance the signal from scattering. Rietveld analysis of XRD data showed that the studied samples presented the lanthanum chromite with an orthorhombic structure (Pnma), except for the composition with x=0.30, in which the space group was found to be R3c.
APA, Harvard, Vancouver, ISO, and other styles
2

Murphy, Michael W., Timothy R. Armstrong, and Peter A. Smith. "Tape Casting of Lanthanum Chromite." Journal of the American Ceramic Society 80, no. 1 (January 1997): 165–70. http://dx.doi.org/10.1111/j.1151-2916.1997.tb02805.x.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Suvorov, S. A., and A. P. Shevchik. "Chemical Equilibria Involving Lanthanum Chromite." Refractories and Industrial Ceramics 45, no. 2 (March 2004): 94–99. http://dx.doi.org/10.1023/b:refr.0000029615.98571.67.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Yamagata, Chieko, and Sonia Regina Homem de Mello-Castanho. "Synthesis Characterization and Sintering of Cobalt-Doped Lanthanum Chromite Powders for Use in SOFCs." Materials Science Forum 660-661 (October 2010): 971–76. http://dx.doi.org/10.4028/www.scientific.net/msf.660-661.971.

Full text
Abstract:
Doped lanthanum chromite is a promising as interconnect material because of its good conductivity at high temperatures and its stability in oxidizing and reducing atmospheres. Perovskite oxide powders of Co-doped lanthanum chromite were synthesized by dispersing precursor metal salt solutions in a polymer matrix followed by a thermal treatment. XRD patterns showed that a highly crystalline cobalt-doped lanthanum chromite was obtained. Fine perovskite powder with a surface area of 6.15 m2 g-1 calcined at 700oC for 1 h, were obtained. After the sample sintered at 1450oC for 3h, the powder reached high densities exceeding 97% of the theoretical density. The proposed here has proved to be a very promising technique for the synthesis of lanthanum chromite powders.
APA, Harvard, Vancouver, ISO, and other styles
5

Pimentel, Patrícia Mendonça, Kaique Matheus Barbosa Ferreira, Danielle Karinne Souza Gomes, Asenete Frutuoso Costa, Dulce Maria de Araújo Melo, and Rosane Maria Pessoa Betânio Oliveira. "Optical and Structural Properties of Lanthanum Chromite Synthesized by Microwave Assisted Self-Combustion Method." Materials Science Forum 881 (November 2016): 7–11. http://dx.doi.org/10.4028/www.scientific.net/msf.881.7.

Full text
Abstract:
Lanthanum chromite is a perovskite oxide type, which exhibit high mechanical and chemical stability, high electric conductivity for use in SOFC and catalytic activity for the oxidation reaction. However, their optical properties have not yet been studied. The aim of this study was to synthesize lanthanum chromite by the microwave assisted self-combustion method for use as ceramic pigment. The resulting precursor powders were calcined at 800 to 1000 ° C to obtain the perovskite phase and characterized by X-ray diffraction, followed by Rietveld refinement, UV-Visible and colorimetry. The results revealed porous powders, nanometric, and single-phase with orthorhombic perovskite structure. There was few change in the colorimetric parameters, the chromites presented colours with gray tones which became darker in the calcined powder at higher temperatures.
APA, Harvard, Vancouver, ISO, and other styles
6

De Guire, M. R., S. E. Dorris, R. B. Poeppel, S. Morissette, and U. Balachandran. "Coprecipitation synthesis of doped lanthanum chromite." Journal of Materials Research 8, no. 9 (September 1993): 2327–35. http://dx.doi.org/10.1557/jmr.1993.2327.

Full text
Abstract:
Two coprecipitation methods were used to synthesize powder precursors of doped lanthanum chromite (La, Ca)(Cr, Co)O3. The effects of synthesis method and calcination temperature on the composition, sintered density, and microstructure of pressed compacts of (La, Ca)(Cr, Co)O3 were studied by differential thermal analysis/thermogravimetric analysis, x-ray diffraction, scanning electron microscopy, and density measurement. The cation ratios in the precipitated solids were, with few exceptions, within experimental error of the desired compositions for all four components. Powders obtained by both techniques could be sintered to densities exceeding 93% at 1400 °C. The highest densities were obtained with calcining temperatures from 450 to 700 °C. The sintered microstructures exhibited uniform grain sizes averaging 3–5 μm. The Cr(vi) compounds, CaCrO4 and La2CrO6, were observed in all of the calcined powders. The possible role of these phases on chromite densification is discussed.
APA, Harvard, Vancouver, ISO, and other styles
7

KONNO, Hidetaka, Masahiro TOKITA, Satoru KITAZAKI, and Ryusaburo FURUICHI. "Electrochemical formation of lanthanum chromite coatings." Journal of the Surface Finishing Society of Japan 40, no. 1 (1989): 144–45. http://dx.doi.org/10.4139/sfj.40.144.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Armstrong, Timothy R., Jeffry W. Stevenson, Larry R. Pederson, and Paige E. Raney. "Dimensional Instability of Doped Lanthanum Chromite." Journal of The Electrochemical Society 143, no. 9 (September 1, 1996): 2919–25. http://dx.doi.org/10.1149/1.1837127.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Carter, J. D. "Solubility of Calcium in Lanthanum Chromite." ECS Proceedings Volumes 1993-4, no. 1 (January 1993): 344–53. http://dx.doi.org/10.1149/199304.0344pv.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Sakai, Natsuko. "Thermodynamic Properties of Lanthanum Calcium Chromite." ECS Proceedings Volumes 1995-1, no. 1 (January 1995): 895–904. http://dx.doi.org/10.1149/199501.0895pv.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Lanthanum chromite"

1

Morelli, Marcio Raymundo. "Liquid phase sintering of perovskite." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297279.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Tinti, Victor Buratto. "Síntese e caracterização de nanopartículas de Ni em matriz de cromita de lantânio." reponame:Repositório Institucional da UFABC, 2017.

Find full text
Abstract:
Orientador: Prof. Dr. Daniel Zanetti de Florio
Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, 2017.
A obtencao de nanoparticulas por exsolucao e uma tecnica que tem sido extensivamente pesquisada e aprimorada recentemente. As particulas exsolvidas apresentam propriedades superiores quando comparadas as depositadas. O metodo de exsolucao consiste na reducao de ions previamente solubilizados em uma matriz, dando origem a particulas fortemente ligadas ao substrato. Materiais com composicoes (La1-xSrx)z(Cr1-yNiy)O3-¿Â (x e y = 0%, 5%, 10%, 15% e 20%; z = 100% e 80%) foram sintetizados, utilizando o metodo de polimerizacao de complexos. A resina produzida no processo de sintese foi analisada utilizando tecnicas de analise termica, tal que a temperatura de calcinacao foi determinada sendo igual a 900 ¿C. Foi utilizada a tecnica de difracao de raios X para caracterizacao estruturas e identificacao das fases presentes. Todas as amostras foram reduzidas com objetivo de criar, atraves de exsolucao, nanoparticulas de niquel metalico. Analises magneticas foram conduzidas para determinar o comportamento magnetico dos materiais produzidos. Materiais nao estequiometricos foram sintetizados para verificar a influencia de diferentes estequiometrias no processo de exsolucao. O sitio A nao estequiometrico prejudicou a solubilizacao do Ni e Sr na estrutura da cromita de lantanio. Todas as amostras com dopantes apresentaram uma diminuicao da temperatura de Neel da cromita de lantanio. Entretanto, o tratamento de reducao provocou um aumento da temperatura de Neel, se comparado com as amostras oxidadas. Esse e um indicativo da diminuicao de concentracao de niquel em solucao solida, um resultado condizente com o mecanismo de exsolucao. Utilizando as medidas de magnetismo foi possivel verificar o mecanismo de exsolucao e fracao massica de niquel metalico para cada amostra. Utilizando tecnicas de microscopia eletronica foi possivel detectar a presenca de nanoparticulas apos o tratamento de reducao com diametro de aproximadamente 20 nm. Ao realizar uma analise quimica local utilizando um microscopio eletronico de transmissao, foi possivel verificar que as particulas em questao sao de niquel metalico.
The production of nanoparticles by exsolution is a technique that has been extensively researched and improved recently. Exsolved particles have superior properties when compared to deposited particles. The method of exsolution consists in the reduction of previously solubilized ions in a matrix, giving rise to particles strongly attached to the substrate. Materials with compositions (La1-xSrx)z(Cr1-yNiy)O3-ä (x and y = 0%, 5%, 10%, 15% and 20%, z = 100% and 80%) were synthesized using the polymerization of complexes technique. The resin produced in the synthesis process was analysed using thermal analysis and the calcination temperature was determined to be 900 ° C. The X-ray diffraction technique was used to characterize structures and identify the present phases. All samples were reduced in order to create nanoparticles of metallic nickel by exsolution. Magnetic analysis was conducted to determine the magnetic behaviour of the produced materials. Non-stoichiometric materials were synthesized to verify the influence of different stoichiometry in the exsolution process. Non-stoichiometric A site impaired the solubilisation of Ni and Sr in the lanthanum chromite structure. All samples with dopants showed a decrease in the temperature of Neel of the lanthanum chromite. However, the reduction treatment caused an increase in the Neel temperature when compared to the oxidized samples. This is indicative of the decrease in nickel concentration in solid solution, a result consistent with the exsolution mechanism. Using the measurements of magnetism it was possible to verify the mechanism of exsolution and mass fraction of metallic nickel for each sample. Using electron microscopy techniques it was possible to detect the presence of nanoparticles after the reduction treatment with a diameter of approximately 20 nm. When performing a local chemical analysis using a transmission electron microscope, it was possible to verify that the particles in question are of metallic nickel.
APA, Harvard, Vancouver, ISO, and other styles
3

Silva, Junior Romualdo Santos. "Propriedades estruturais, elétricas e ópticas do composto LaCrO3 dopado com Al produzido pelo método da combustão." Pós-Graduação em Física, 2018. http://ri.ufs.br/jspui/handle/riufs/9245.

Full text
Abstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
In the present work, we performed a study of the structural, electrical and optical properties of the compound LaCr1-xAlxO3 (x = 0.0, 0.05, 0.5, 0.95 and 1.0) produced by the combustion method. The structural analyzes were performed by X-ray diffraction (XRD) and Rietveld refinement, the electrical measurements using impedance spectroscopy and IV measurements, and optical measurements using UV-Vis spectroscopy. The results of XRD allied to the Rietveld method of refinement indicate that the samples with x = 0.0 and 0.05, have an orthorhombic structure belonging to the space group Pnma (62), and for x = 0.5, 0.95 and 1.0, a rhombohedral structure belonging to the space group R-3c (167), thus taking place a structural transition in the material. The impedance spectroscopy measurements associated to the IV curves show that the samples with higher concentration of Al present higher resistance, and the samples with lower concentration of Al present less resistance. We observe that for high frequencies a decrease of dielectric constant with frequency occurs. In addition, the appearance of only a semicircle establishes the presence of non-Debye type relaxation, where an equivalent circuit composed of two resistors (R1 and R2) and a constant phase element (CPE) were used. By means of the absorption measurements in the ultraviolet to visible region (UV-Vis), we estimated the optical gap of the samples, through the tauc equation, which vary between 3.27 - 3.43 eV. Still, we observed that the increase in Al concentration favors the increase in transmittance in the material.
No presente trabalho, realizamos um estudo das propriedades estruturais, elétricas e ópticas do composto LaCr1-xAlxO3 (x=0,0; 0,05; 0,5; 0,95 e 1,0) produzido pelo método da combustão. As análises estruturais foram realizadas por meio de difração de raios-X (DRX) e refinamento Rietveld, as elétricas por meio de espectroscopia de impedância e medidas IV, e ópticas por meio de espectroscopia de UV-Vis. Os resultados de DRX aliados ao método de refinamento Rietveld indicam que as amostras com x = 0,0 e 0,05, apresentam uma estrutura ortorrômbica pertencente ao grupo espacial Pnma (62), e para x = 0,5; 0,95 e 1,0, uma estrutura romboédrica pertencente ao grupo espacial R-3c (167), ocorrendo assim uma transição estrutural no material. As medidas de espectroscopia de impedância associadas às curvas IV mostram que as amostras com maior concentração de Al apresentam maior resistência, e as amostras com menor concentração de Al apresentam menor resistência. Observamos que para altas frequências ocorre uma diminuição da constante dielétrica com a frequência. Além disso, o aparecimento de apenas um semicírculo estabelece a presença do relaxamento do tipo não-Debye, onde foi utilizado um circuito equivalente composto por duas resistências (R1 e R2), e um elemento de fase constante (CPE). Através das medidas de absorção na região do ultravioleta ao visível (UV-Vis) estimamos o gap óptico das amostras, através da equação de tauc, os quais variam entre 3,27 - 3,43 eV. Além disso, observamos que o aumento da concentração de Al favorece o aumento da transmitância no material.
São Cristóvão, SE
APA, Harvard, Vancouver, ISO, and other styles
4

Sousa, Cl?wsio Rog?rio Cruz de. "Estudo termo-mec?nico de interconector met?lico recoberto com filme de La0,8Ca0,2CrO3 e de interconector cer?mico de La0,8Sr0,2Cr0,92Co0,08O3 para PaCOS." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12864.

Full text
Abstract:
Made available in DSpace on 2014-12-17T14:07:21Z (GMT). No. of bitstreams: 1 ClawsioRCS_TESE.pdf: 6209957 bytes, checksum: 4a85a36be678a5c36d937dd4cb67fe7c (MD5) Previous issue date: 2014-04-28
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Doped lanthanum chromite ( LaCrO3 ) has been the most common material used as interconnect in solid oxide fuel cells for high temperature ( SOFC-HT ) that enabling the stack of SOFCs. The reduction of the operating temperature, to around 800 ? C, of solid oxide fuel cells enabled the use of metallic interconnects as an alternative to ceramic LaCrO3, From the practical point of view, to be a strong candidate for interconnect the material must have good physical and mechanical properties such as resistance to oxidizing and reducing environments, easy manufacture and appropriate thermo-mechanical properties. Thus, a study on the physic-mechanical interconnects La0,8Sr0,2Cr0,92Co0,08O3 ceramics for SOFC -AT obtained by the method of combustion , as well as thermo-mechanical properties of metallic interconnects (AISI 444) covered with La0,8Ca0,2CrO3 by deposition technique by spray-pyrolysis fuel cells for intermediate temperature (IT-SOFCs). The La0,8Sr0,2Cr0,92Co0,08O3 was characterized by X -ray diffraction(XRD) , density and porosity , Vickers hardness (HV) , the flexural strength at room temperature and 900 ?C and scanning electron microscopy (SEM). The X -ray diffraction confirmed the phase formation and LaCrO3 and CoCr2O4, in order 6 GPa hardness and mechanical strength at room temperature was 62 MPa ceramic Interconnector. The coated metal interconnects La0,8Ca0,2CrO3 passed the identification by XRD after deposition of the film after the oxidation test. The oxidative behavior showed increased resistance to oxidation of the metal substrate covered by La0,8Ca0,2CrO3 In flexural strength of the coated metal substrate, it was noticed only in the increased room temperature. The a SEM analysis proved the formation of Cr2O3 and (Cr,Mn)3O4 layers on metal substrate and confirmed the stability of the ceramic La0,8 Ca0,2CrO3 film after oxidative test
A cromita de lant?nio (LaCrO3) dopada tem sido o material mais utilizado como interconector nas pilhas a combust?vel de ?xido s?lido de alta temperatura(PaCOS-AT), possibilitando o empilhamento(stack) da PaCOS. A redu??o da temperatura de opera??o, em torno de 800 ?C, das pilhas a combust?vel de ?xido s?lido, tornou poss?vel o uso de interconectores met?licos como alternativa aos LaCrO3 cer?micos. Do ponto de vista pr?tico para o material ser forte candidato a interconector deve ter boas propriedades f?sicas e mec?nicas, como resist?ncia a ambientes oxidantes e redutores, f?cil fabrica??o e propriedades termo-mec?nicas adequadas. Por este motivo realizou-se um estudo sobre as propriedades fisico-mec?nicas de interconectores de La0,8Sr0,2Cr0,92Co0,08O3 cer?mico para PaCOS-AT obtido pelo m?todo da combust?o, como tamb?m sobre as propriedades termo-mec?nicas de interconectores met?licos (AISI 444) recobertos com La0,8Ca0,2CrO3 pela t?cnica de deposi??o por spray-pir?lise para Pilhas a combust?vel de temperatura intermediaria (PaCOS-TI). A La0,8Sr0,2Cr0,92Co0,08O3 foi caracterizada por meio de difra??o de raios X (DRX), densidade e porosidade, dureza Vickers (HV), resist?ncia mec?nica a flex?o na temperatura ambiente e a 900?C e microscopia eletr?nica de varredura (MEV). A difra??o de raios X comprovou a forma??o das fases LaCrO3 e CoCr2O4, dureza na ordem de 6 GPa e resist?ncia mec?nica a temperatura ambiente de 62 MPa do interconector cer?mico. A avalia??o das fases formadas no interconector met?lico recoberto com La0,8Ca0,2CrO3 tanto na deposi??o quanto ap?s o ensaio oxidativo foi realizado por DRX. O comportamento oxidativo evidenciou o aumento da resist?ncia a oxida??o do substrato met?lico recoberto por La0,8Ca0,2CrO3. Na resist?ncia mec?nica a flex?o do substrato met?lico recoberto, notou-se o aumento apenas na temperatura ambiente. Com aux?lio do MEV comprovou-se a forma??o das camadas de Cr2O3 e (Cr,Mn)3O4 sobre o substrato met?lico e confirmou-se a estabilidade do filme cer?mico de La0,8Ca0,2CrO3 ap?s o ensaio oxidativo
APA, Harvard, Vancouver, ISO, and other styles
5

Huang, Ming-Hsien. "Preparation of some Mg-doped lanthanum chromites for solid oxide fuel cell applications." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46828.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Huang, An-Rong. "Synthèse par procédé sol-gel du chromite de lanthane pour éléments chauffants." Montpellier 2, 1995. http://www.theses.fr/1995MON20039.

Full text
Abstract:
Des poudres de chromite de lanthane ont ete preparees par procede sol-gel en milieu aqueux a partir de deux precurseurs: nitrates ou acetates. Les sols colloidaux ont ete obtenus par precipitation et peptisation en ajoutant de l'ammoniaque. Les zones de ph de precipitation et de peptisation ont ete determinees par des dosages acidobasiques. Apres gelification a l'air, la decomposition des gels a ete etudiee par analyse thermique (atg - atd) et par spectroscopie ir ; la cristallisation du chromite de lanthane, obtenu par traitement thermique des gels a ete determinee par diffractometrie des rx sur poudre. Des elements chauffants tubulaires ont ete realises par la methode d'extrusion avec les poudres ainsi obtenues. La composition de pates ceramiques permettant cette mise en forme a ete determinee. Une analyse thermomecanique par dilatometrie a permis de suivre le comportement au frittage des preformes, et de determiner la temperature de frittage convenable pour differentes compositions. Les poudres et les ceramiques ont ete caracterisees par meb, bet, porosimetrie a mercure, et par la mesure de la conductivite electrique
APA, Harvard, Vancouver, ISO, and other styles
7

SETZ, LUIZ F. G. "Obtencao de Lasub(1-x)Srsub(x)Crsub(1-y)Cosub(y)Osub(3) por reacao de combustao." reponame:Repositório Institucional do IPEN, 2005. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11237.

Full text
Abstract:
Made available in DSpace on 2014-10-09T12:49:48Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:03:15Z (GMT). No. of bitstreams: 1 10384.pdf: 9700840 bytes, checksum: b2fbf22494ca3f10b89bc09793b74be1 (MD5)
Dissertacao (Mestrado)
IPEN/D
Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP
APA, Harvard, Vancouver, ISO, and other styles
8

Brown, Jared C. "UV Visible Spectra Analysis of High Temperature Water Gas Shift Catalysts Made from Iron, Lanthanum, Copper, and Chromium Oxides." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3222.

Full text
Abstract:
Hydrogen is a vital component in several different chemical reactions as well as a potential fuel source for the future. The water gas shift (WGS) reaction converts CO and water to hydrogen and CO2. The objective of this work is to first, characterize the potential benefits of the addition of lanthanum oxide (lanthana) to the iron-chromium-copper (Fe-Cr-Cu) oxide catalysts industrially used in high temperature water gas shift processes, and second, analyze these catalysts using in-situ UV-Visible spectroscopy. The benefits of each component in the catalyst are discussed as well as potential benefits from the addition of lanthana. Lanthana is a rare earth oxide that dramatically increases the surface area of the iron based WGS catalysts, and small concentrations of other rare earth oxides (i.e. cerium) have been shown to increase the rate of desorption of CO2 from iron surfaces (Hu Yanping 2002). Lanthana has similar chemical properties to other rare earth oxides tested and has not been previously tested as an additive to the WGS catalyst. Therefore catalysts with 0, 1, 2, 5, 10, and 20 wt% lanthana were made via a co-precipitation method in order to measure changes in activity, physical stability, and thermal stability. Catalyst characterization techniques utilized include electron dispersive X-ray spectroscopy (EDX), temperature programmed reduction (TPR) with hydrogen, and nitrogen physisorption (BET). The kinetic analysis was performed utilizing both mass spectroscopy (MS) and gas chromatography (GC). The addition of 1 wt% lanthana to the Fe-Cr-Cu catalysts increases WGS reaction rates of the catalyst at 425°C and 350°C, however the 0% La catalyst has the highest rates at 375°C and 400°C. The 0% La catalyst shows significant drop off in rate at 425°C, suggesting that the lanthana provides a small thermal stabilizing, i.e. the addition of lanthana prevents catalyst sintering at higher temperatures. Traditionally, chromia acts as the sole thermal stabilizer in these catalysts. The addition of large amounts of lanthana inhibits the chromia stabilizing effect, however small additions of lanthana appear to have an additional catalyst promotional effect without interfering with the chromia thermal stabilization. The increased WGS reaction rates at higher temperatures could allow for greater throughput of reactants in industrial settings. Higher concentrations of lanthana decrease the activity due to what is believed to be disruption of the chromia stabilizing effect as well as reduced amount of the active phase of catalyst. In-situ UV-Visible analysis shows that the oxidation state of the iron in the catalyst has a direct correlation to the UV-Visible light absorbance of the surface of the iron catalyst. Extent of reduction is traditionally measured with a synchrotron which is significantly more expensive than UV-Vis spectroscopy. This study uses the more economical UV-Vis spectrometer to determine similar information. The lanthana doped catalysts show an over-reduction of iron during WGS conditions (i.e. rapid reduction of Fe2O3 to Fe3O4 and FeO).
APA, Harvard, Vancouver, ISO, and other styles
9

Jin, Tongan. "Interactions of the Air Electrode with Electrolyte and Interconnect in Solid Oxide Cells." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/39223.

Full text
Abstract:
The interactions between different components of solid oxide cells (SOCs) are critical issues for achieving the tens of thousands of hourâ s goal for long-term performance stability and lifetime. The interactions between the ceramic electrolyte, porous ceramic air electrode, and metallic interconnect materials â including solid state interfacial reactions and vaporization/deposition of some volatile elements â have been investigated in the simulated SOC operating environment. The interactions demonstrate the material degradation mechanisms of the cell components and the effects of different factors such as chemical composition and microstructure of the materials, as well as atmosphere and current load on the air electrode side. In the aspect of materials, this work contributes to the degradation mechanism on the air electrode side and provides practical material design criteria for long-term SOC operation. In this research, an yttria-stabilized zirconia electrolyte (YSZ)/strontium-doped lanthanum manganite electrode (LSM)/AISI 441 stainless steel interconnect tri-layer structure has been fabricated in order to simulate the air electrode working environment of a real cell. The tri-layer samples have been treated in dry/moist air atmospheres at 800°C for up to 500 h. The LSM air electrode shows slight grain growth, but the growth is less in moist atmospheres. The amount of Cr deposition on the LSM surface is slightly more for the samples thermally treated in the moist atmospheres. At the YSZ/LSM interface, La enrichment is significant while Mn depletion occurs. The Cr deposition at the YSZ/LSM interface is observed. The stoichiometry of the air electrode is an important factor for the interactions. The air electrode composition has been varied by changing the x value in (La0.8Sr0.2)xMnO3 from 0.95 to 1.05 (LSM95, LSM100, and LSM105). The enrichment of La at the YSZ/LSM interface inhibits the Cr deposition. The mechanisms of Cr poisoning and LSM elemental surface segregation are discussed. A 200 mA·cm-2 current load have been applied on the simulated cells. Mn is a key element for Cr deposition under polarization. Excessive Mn in the LSM lessens the formation of La-containing phases at the YSZ/LSM interface and accelerates Cr deposition. Deficient Mn in LSM leads to extensive interfacial reaction with YSZ forming more La-containing phase and inhibiting Cr deposition.
Ph. D.
APA, Harvard, Vancouver, ISO, and other styles
10

BOREL, CORINNE. "Cristallogenese et caracterisation d'hexaaluminates de lanthane dopes aux ions chrome et titane pour la realisation de nouveaux lasers accordables." Paris 6, 1990. http://www.theses.fr/1990PA066732.

Full text
Abstract:
L'etude des monocristaux d'hexaaluminates mixtes de lanthane et magnesium, de formule lamgal11019 (lma), dopes aux ions cr3+ et ti3+, pour la realisation de nouveaux materiaux laser accordables dans le visible et proche infra-rouge (600-1200 nm), s'est deroulees en trois etapes: cristallogenese et amelioration de la qualite cristalline, etude des proprietes spectroscopiques d'absorption et d'emission et essais laser en cavite. Aucun des deux materiaux n'a donne lieu a une emission laser: le lma:cr de bonne qualite cristalline possede des proprietes d'emission mediocres, principalement dues a l'existence de plusieurs sites emetteurs de sections efficaces d'emission stimulee faible et de transferts d'energie entre ces sites. Le lma:ti presente de nombreux defauts cristallins, lies a une forte segregation du titane. De plus il presente des bandes d'absorption parasites dans la zone d'absorption et d'emission de l'ion ti#3#+, liees sans doute a la presence d'ions ti#4#+, ti#2#+ et/ou de lacunes cationiques. Des recherches pour diminuer ces bandes parasites ont ete entreprises (codopages, recuits. . . )
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Lanthanum chromite"

1

Gore, Russell Bryan. The relationship of minor phase concentration to sintering densification of Sr and Ca doped LaCrO₃ and YCrO₃. 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Lanthanum chromite"

1

Franco, Adolfo, and Cirilo Gomes Valente Neto. "Characterization of Lanthanum Chromite Powders Obtained by Combustion Reaction." In Ceramic Transactions Series, 93–100. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118408476.ch9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Setz, L. F. G., H. P. S. Corrêa, C. O. Paiva-Santos, and Sonia R. H. Mello Castanho. "Sintering of Cobalt and Strontium Doped Lanthanum Chromite Obtained by Combustion Synthesis." In Materials Science Forum, 671–76. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-423-5.671.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Setz, L. F. G., H. P. S. Correa, C. Yamagata, and S. R. H. Mello-Castanho. "Synthesis and Sintering Behavior of Lanthanum Chromite Doped with Strontium and Cobalt for SOFC Interconnect Applications." In Advances in Solid Oxide Fuel Cells III, 237–54. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2009. http://dx.doi.org/10.1002/9780470339534.ch23.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Yamanaka, Ichiro, and Yuta Nabae. "Direct Oxidation of Dry Methane by Pd-Ni Synergy Catalyst Supported on Lanthanum Chromite Based Anode." In Advances in Science and Technology, 2067–76. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/3-908158-01-x.2067.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Perrot, Pierre. "Chromium – Lanthanum – Oxygen." In Refractory metal systems, 156–69. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-00771-2_12.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Belda, Charif, Egle Dietzen, Mihails Kusnezoff, Nikolai Trofimenko, Uladimir Vashook, Alexander Michaelis, and Ulrich Guth. "Interaction of perovskite type lanthanum-calcium-chromites-titanates La1−xCaxCr1−yTiyO3−δwith solid electrolyte materials." In Advances in Solid Oxide Fuel Cells X, 41–53. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119040637.ch5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Hoang, D. L., A. Trunschke, A. Brückner, J. Radnik, and H. Lieske. "Studies on a chromia/lanthana/zirconia aromatization catalyst." In Studies in Surface Science and Catalysis, 2357–62. Elsevier, 2000. http://dx.doi.org/10.1016/s0167-2991(00)80821-6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Shkrabina, R. A., N. A. Koryabkina, O. A. Kirichenko, V. A. Ushakov, F. Kapteijn, and Z. R. Ismagilov. "Thermostability of copper-chromium oxide catalysts on alumina support promoted by lanthanum and cerium." In Studies in Surface Science and Catalysis, 1145–52. Elsevier, 1995. http://dx.doi.org/10.1016/s0167-2991(06)81859-8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Combemale, Lionel, Denis Chaumont, Gilles Caboche, and Didier Stuerga. "Synthèse sous champ micro-onde et caractérisation de chromite de lanthane strontium dopé utilisé comme anode de pile à combustible SOFC." In Énergie et formulation, 132–40. EDP Sciences, 2020. http://dx.doi.org/10.1051/978-2-7598-0143-5.c012.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Lanthanum chromite"

1

Blinov, Y., I. Pozniak, A. Shatunov, A. Pechenkov, and A. Zuev. "Electrical conductivity measurement of lanthanum chromite melts." In IEEE EUROCON 2009 (EUROCON). IEEE, 2009. http://dx.doi.org/10.1109/eurcon.2009.5167858.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Suvorov, Sergey, Andrey Zuev, Igor Pozniak, Andrey Pechenkov, Alexey Shatunov, Maxim Kydryash, Benjamin Niemann, and Bernard Nacke. "Functional materials on the base of lanthanum chromite." In 2008 Third International Forum on Strategic Technologies (IFOST). IEEE, 2008. http://dx.doi.org/10.1109/ifost.2008.4602902.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Sinha, R., S. Basu, and A. K. Meikap. "Investigation of electrical behavior of lanthanum doped yttrium chromite nanoparticles." In DAE SOLID STATE PHYSICS SYMPOSIUM 2016. Author(s), 2017. http://dx.doi.org/10.1063/1.4980304.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Naseem, Swaleha, Wasi Khan, A. A. Saad, M. Shoeb, Hilal Ahmed, Shahid Husain, and A. H. Naqvi. "Variation in band gap of lanthanum chromate by transition metals doping LaCr0.9A0.1O3 (A:Fe/Co/Ni)." In SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4872565.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Lanthanum chromite"

1

Paulik, S. W., and T. R. Armstrong. Mechanical properties of lanthanum and yttrium chromites. Office of Scientific and Technical Information (OSTI), December 1996. http://dx.doi.org/10.2172/460182.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Lanthanum chromite' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography