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Статті в журналах з теми "Doped POT":
Bhat, Vighneshwar S., T. S. Tilakraj, Mallikarjun K. Patil, Vikram Pujari, and Sanjeev R. Inamdar. "One-Pot Synthesis of Biocompatible Glycine Protected Chromium Doped ZnS Nanoparticles and their Optical Properties." IOP Conference Series: Materials Science and Engineering 1221, no. 1 (March 1, 2022): 012029. http://dx.doi.org/10.1088/1757-899x/1221/1/012029.
Zhang, Hui, Ye Han, Limeng Yang, Xiaoling Guo, Hailiang Wu, and Ningtao Mao. "Photocatalytic Activities of PET Filaments Deposited with N-Doped TiO2 Nanoparticles Sensitized with Disperse Blue Dyes." Catalysts 10, no. 5 (May 11, 2020): 531. http://dx.doi.org/10.3390/catal10050531.
Casco, Mirian Elizabeth, Sebastian Kirchhoff, Desirée Leistenschneider, Marcus Rauche, Eike Brunner, and Lars Borchardt. "Mechanochemical synthesis of N-doped porous carbon at room temperature." Nanoscale 11, no. 11 (2019): 4712–18. http://dx.doi.org/10.1039/c9nr01019j.
Dhiman, Nitesh, Markandeya Markandeya, Faimy Fatima, Prem N. Saxsena, Somendu Roy, Prashant K. Rout, and Satyakam Patnaik. "Predictive modeling and validation of arsenite removal by a one pot synthesized bioceramic buttressed manganese doped iron oxide nanoplatform." RSC Advances 7, no. 52 (2017): 32866–76. http://dx.doi.org/10.1039/c7ra03736h.
Wang, Miao, Yu Zhang, Michael Ng, Artiom Skripka, Ting Cheng, Xu Li, Kishore Kumar Bhakoo, Alex Y. Chang, Federico Rosei, and Fiorenzo Vetrone. "One-pot synthesis of theranostic nanocapsules with lanthanide doped nanoparticles." Chemical Science 11, no. 26 (2020): 6653–61. http://dx.doi.org/10.1039/d0sc01033b.
Hosseini, Morteza, Mustafa Aghazadeh, and Mohammad Reza Ganjali. "A facile one-pot synthesis of cobalt-doped magnetite/graphene nanocomposite as peroxidase mimetics in dopamine detection." New J. Chem. 41, no. 21 (2017): 12678–84. http://dx.doi.org/10.1039/c7nj02082a.
Yan, Tinghua, Wang Zhong, Ruiming Yu, Gao Yi, Zeping Liu, Lihong Liu, Xinxing Wang, and Jinhua Jiang. "Nitrogen-doped fluorescent carbon dots used for the imaging and tracing of different cancer cells." RSC Advances 9, no. 43 (2019): 24852–57. http://dx.doi.org/10.1039/c9ra03170g.
Feng, Zijuan, Deru Lian, Xue Wu, Yi Liu, Wen Jia, and Xiaoya Yuan. "The synergy of N-doped and SPR-promoted photocatalytic removal of NO with graphene/Bi nanocomposites." RSC Advances 10, no. 5 (2020): 2734–39. http://dx.doi.org/10.1039/c9ra10001f.
Guo, Yaoping, Zequan Zeng, Yongjin Liu, Zhanggen Huang, Yan Cui, and Jieyang Yang. "One-pot synthesis of sulfur doped activated carbon as a superior metal-free catalyst for the adsorption and catalytic oxidation of aqueous organics." Journal of Materials Chemistry A 6, no. 9 (2018): 4055–67. http://dx.doi.org/10.1039/c7ta09814f.
Gunasekaran, Sivagaami Sundari, and Sushmee Badhulika. "N-Doped carbon as the anode and ZnCo2O4/N-doped carbon nanocomposite as the cathode for high-performance asymmetric supercapacitor application." New Journal of Chemistry 45, no. 21 (2021): 9550–60. http://dx.doi.org/10.1039/d1nj01526e.
Дисертації з теми "Doped POT":
Cai, Zhiwei. "Nouveaux matériaux à base de polyoxotitanates (POTs) dopé ou à base de complexe salicylate de titane (IV) et d'argent (I)." Electronic Thesis or Diss., Strasbourg, 2023. http://www.theses.fr/2023STRAF062.
In recent years, titanium dioxide has attracted much attention as a highly stable material with a wide range of applications from white pigment to its applications as a semiconductor or advanced photonic devices. Using recently developed synthetic approaches, the synthesis of atomically well-defined polyoxotitanate (POT, [TixOy(OR)z]) cage molecules can be determined. POTs may be preferred as soluble models of TiO2. Cages doped with a metal M (M-POT) presenting new properties can also be prepared.Two new cages doped with cerium were synthesized by a solvothermal reaction. The cages [Ti28O38(OEt)38CeCl](EtOH)1.4 and [Ti8O7(OEt)21Ce](EtOH) having different solubilities, they will be able to be separated and characterized by 1H NMR and X-ray diffraction. The Fe-doped POTs: [Ti4(OEt)15O(FeCl)] and [FeTi14(OEt)28O14(OH)2] were also synthesized. Then after hydrolysis with or without calcination, materials based on Ce or Fe and TiO2 can be obtained. Emulsions of its materials and with the cerium-doped PVDC polymer were then deposited on a PVC surface. UV absorption and water barrier performance gradually increases with increasing amount of deposited materials. The results are interesting for the use of these materials on the packaging surface of drug tablets, which will increase their expiry date. The Eu-POT cage doped with the Eu(III): Ti2O(OEt)8EuIIICl(EtOH)]2 was also synthesized, then after hydrolysis and calcination, the photoluminescence properties of the obtained material were studied.Finally, an AgITiIV(SC)2(HSC)(CH3CN) complex (SC2- = salicylate) was prepared. After hydrolysis and calcination, the anti-microbial properties of the materials were successfully tested against S. aureus or E. Colis
Galiyeva, Perizat. "Doped Ag-In-Zn-S and Ag-In-Ga-Zn-S QDs : synthesis and potential as dual-modality probes for magnetic resonance and fluorescence imaging of cells." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0118.
Since fluorescence imaging (FI) and magnetic resonance imaging (MRI) are among the most effective diagnostic tools, QDs with fluorescent and magnetic properties are of great interest as dual-modal probes. In this work, undoped and doped Ag-In-Zn-S (AIZS) and Ag-In-Ga-Zn-S (AIGZS) QDs were synthesized and investigated as bimodal probes for FI and MRI. Highly fluorescent AIZS QDs were prepared in organic media using DDT and OAm as capping ligands. Mn:AIZS QDs showed paramagnetic and superparamagnetic properties. AIZS and Mn:AIZS QDs were also transferred into aqueous phase using the amphiphilic PMAO polymer. Further, Mn, Gd or Fe-doped AIZS QDs were prepared in aqueous media, showed low cytotoxicity toward KB cells, and demonstrated potential as fluorescent probes for FI. Finally, AIGZS and Mn:AIGZS QDs, synthesized via a novel single precursor thermal decomposition method, showed high fluorescence and paramagnetic/superparamagnetic properties. Mn-doped aqueous transferred AIGZS QDs increased contrast in both T1-weighted and T2-weighted images with increasing in Mn loading
Adell, Barbarà Irina. "Ce or Pr-doped type III KGd(PO3)4 crystalline materials. Growth and characterization as scintillators." Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/668444.
Los materiales centelleadores son ampliamente utilizados como detectores en los sistemas de detección de diversas aplicaciones, como la imagen médica, la física de alta energía, la astrofísica y en pruebas no destructivas (seguridad aeroportuaria, control industrial, etc.). Hay varios requisitos importantes para evaluar favorablemente el rendimiento de un centelleador. Dado que no existe el centelleador ideal, se están dedicando muchos esfuerzos para buscar nuevos centelleadores inorgánicos con mejores propiedades que los de los centelleadores existentes. En esta tesis, se crecen monocristales con alta calidad cristalina de KGd(PO3)4 tipo III dopados con Ce3+ y Pr3+, y también nanocristales de Pr:KGd(PO3)4 tipo III para posteriormente caracterizarlos estructuralmente y ópticamente como posibles nuevos materiales centelleadores. Estos monocristales se crecen a partir de soluciones de alta temperatura mediante la técnica Top Seeded Solution Growth-Slow Cooling (TSSG-SC) y los nanocristales se sintetizan mediante el método de Pechini. La caracterización estructural incluye la morfología cristalina, estabilidad y expansión térmicas, distribución de tamaño de las partículas, entre otros. Se estudia con detalle la espectroscopia de las transiciones 4f-5d, sobre las que se basa el mecanismo de centelleo. Incluye medidas de absorción óptica, medidas de luminiscencia y del tiempo de decaída de ésta excitando con luz de sincrotrón en el rango espectral desde el ultravioleta de vacío hasta el ultravioleta (VUV-UV), medidas de radioluminiscencia excitando con rayos X, entre otros. Además, se proporcionan los datos espectroscópicos básicos de los monocristales de Pr:KGd(PO3)4 tipo III para aplicaciones láser en la gama de longitud de onda visible basadas en las transiciones electrónicas 4f-4f. También, se determina la región de cristalización primaria de KYP4O12 tipo B y de KY(PO3)4 tipo IV en el sistema ternario K2O-Y2O3-P2O5, ya que son candidatos interesantes para actuar como matriz para iones lantánidos activos en aplicaciones de centelleo.
Scintillators materials are widely used as detectors in the detection systems of a variety of applications, such as medical imaging, high energy physics, astrophysics and non-destructive testing (airport security, industrial control, etc.). There are several important requirements to evaluate favourably the performance of a scintillator. Since the ideal scintillator does not exist, many efforts are dedicated to find new inorganic scintillators with better properties than those of the existing scintillators. Here, Ce3+- and Pr3+-doped type III KGd(PO3)4 bulk single crystals with high crystalline quality and type III Pr:KGd(PO3)4 nanocrystals are grown and structurally and optically characterized as possible new scintillator materials. These bulk single crystals are grown from high temperature solutions by the Top Seeded Solution Growth-Slow Cooling (TSSG-SC) technique, while the nanocrystals are synthesized by the Pechini method. The structural characterization includes the crystal morphology, thermal stability, thermal expansion, particle size distribution, among others. The spectroscopy of the 4f–5d transitions, on which the scintillation mechanism is based, is studied in detail. The spectroscopic characterization includes optical absorption measurements, luminescence and decay time measurements under synchrotron vacuum ultraviolet-ultraviolet (VUV-UV) excitation, radioluminescence measurements after synchrotron X-ray irradiation, among others. In addition, the basic spectroscopic data of the type III Pr:KGd(PO3)4 crystal for lasing applications in the visible wavelength range based on the 4f–4f electronic transitions is provided. Moreover, the primary crystallization region of type B KYP4O12 and type IV KY(PO3)4 in the K2O–Y2O3–P2O5 ternary system is determined, since these are interesting candidates as hosts for active lanthanide ions in scintillation applications.
Zazou, Hicham. "Dégradation de pesticides dans l’eau par les procédés d’oxydation avancée (POA)." Thesis, Paris Est, 2015. http://www.theses.fr/2015PEST1071/document.
The intensive use of pesticides in agriculture generates, nowadays, an unprecedented contamination of surface water and groundwater. Conventional treatments applied to waste water containing organic pollutants are based on biological treatments méthods or physical mass transfer methods (decantation, filtration, adsorption of the pollutants on activated carbon), chemical oxidation with ozone, chlorine, etc. However, these methods remain ineffective for the treatment of water polluted by persistent organic pollutants (POPs). Advanced oxidation processes are implemented to degrade and mineralize these pollutants. This PhD thesis work aims to establish an experimental protocol to degrade and mineralize pesticides, chemicals widely used in agriculture in Morocco, such as monochlorobenzene, 1,2-dichlorobenzene, 2,4,5-trichlorophenoxy-acetic acid , and imazalil using the electro-Fenton and anodic oxidation processes with DD Pt or DSA anodes. Thus, the rate of mineralization was 92%, 95%, 92% and 97% for the monochloro-benzene, the 1,2-dichlorobenzene, the 2,4,5-trichlorophenoxyacetic acid , and the imazalil, respectively, after 4 h treatment by electro-Fenton process. These results confirm the effectiveness of electrochemical advanced oxidation processes for treating water polluted by pesticides
Parreu, i. Alberich Isabel. "Crystal Growth and Characterization of ytterbium or neodymium doped type III-KGd(PO3)4. A new bifunctional nonlinear and laser crystal." Doctoral thesis, Universitat Rovira i Virgili, 2006. http://hdl.handle.net/10803/9081.
Aquest tipus de fonts làser compactes emetent en el visible poden ésser desenvolupades utilitzant un cristall bifuncional. Aquests làsers auto-dobladors de freqüència tenen associades menys pèrdues (absorció, reflexió i dispersió) que làsers dobladors de freqüència intracavitat, que significa que el disseny del ressonador és més simple i compacte. Actualment, la recerca en aquest camp està centrada en el desenvolupament de nous materials no-centrosimètrics que presentin propietats d'òptica no-lineal i que puguin allotjar ions làser actius, majoritàriament ions lantànid. Els materials d'òptica no-lineal tenen la capacitat de generar el segon harmònic de la radiació, és a dir, de doblar la seva freqüència. Si un material d'òptica no-lineal conté un ió lantànid que generi radiació làser en la regió infraroja d'aproximadament =1000 nm, podrà auto-doblar-ne la freqüència, és a dir, reduir-ne a la meitat la longitud d'ona, =500 nm, que correspon a la regió electromagnètica del blau o el verd.
El fosfat doble de potassi i gadolini de tipus III, KGd(PO3)4 (KGP), que és objecte d'aquesta tesi doctoral, és un cristall d'estructura no-centrosimètrica i per tant amb el requisit estructural necessari per a posseir propietats d'òptica no-lineal. Es va plantejar l'objectiu de sintetitzar i caracteritzar aquest cristall i a més de substituir parcial o totalment l'ió gadolini per un ió lantànid actiu en la zona de 1000 nm, com són l'iterbi i el neodimi, per tal d'aconseguir desenvolupar un nou cristall auto-doblador de freqüència.
Així doncs, l'objectiu de la present tesi doctoral va ésser l'estudi del creixement cristal.lí del KGP i del KGP dopat amb iterbi o neodimi i la seva posterior caracterització. Com que el fosfats doble de potassi i lantànid fonen incongruentment, és a dir, que es descomponen abans de fondre, és necessari utilitzar un mètode de creixement cristal.lí a partir de solució a alta temperatura per créixer cristalls. Aquest mètodes permeten créixer a una temperatura per sota la temperatura de fusió del material, i per tant evitar-ne la seva descomposició. El mètode que nosaltres em utilitzat per créixer monocristalls de KGP pur i dopat és l'anomenat top seeded solution growth-slow cooling (TSSG-SC), que permet créixer els cristalls lliures en la solució disminuint lentament la seva temperatura a partir de la temperatura se cristal.lització. Això permet obtenir cristalls volúmics amb formes cristal.logràfiques desenvolupades lliurament i determinades a partir de l'estructura cristal.lina. Després d'optimitzar el procés de creixement, hem aconseguitr sintetitzar cristalls lliures de macrodefectes i d'una mida suficient pel seu estudi i possible posterior aplicació. Posteriorment, els cristalls han estat caracteritzats estructuralment, físicament, òpticament i espectroscòpicament.
Finalment, s'han realitzat experiències de laserat amb Yb:KGP, obtenint uns resultats força encoratjadors, ja que s'ha aconseguit generar radiació làser per primer cop en aquest cristall dopat amb iterbi amb un nivell de dopatge força baix.
Com a conclusió i després dels resultats de l'estudi, podem dir que els cristalls de Yb:KGP i Nd:KGP poden ésser considerats com a candidats prometedors per a ser aplicats com a cristalls auto-dobladors de freqüència ja que s'ha provat la seva capacitat tant de generar segon harmònic com de generar radiació làser.
Bifunctional crystals are those in which the nonlinear optical process and the laser effect occur simultaneously. This kind of materials is very promising for compact solid-state laser designs operating in the visible because solid-state lasers operate mainly in the infrared. So, the nonlinear and laser properties can combine to generate blue (≈ 450 nm) or green (≈550 nm) laser radiation by self-frequency doubling. Solid-state laser sources operating in the visible spectral region (≈400-800 nm) play an important role in laser technology they are potentially interesting for numerous applications such as high-density optical data storage, reprographics, colour displays, medicine, biotechnology, submarine communications, transparent atmosphere communications, etc.
Such compact laser sources can be managed from frequency conversion by nonlinear optical processes such as frequency doubling and sum-frequency mixing by using a bifunctional crystal. Such self-frequency doubling (SFD) lasers involve fewer losses (absorption, reflection and scattering) than the intracavity frequency doubling lasers, which means that resonator designs are simpler and more compact.
Currently, efforts are focussed on the development of new noncentrosymmetric crystals with nonlinear optical properties to be used as a host for active laser ions, and mostly lanthanide ions. Nonlinear optical materials are able to double the frequency of the laser emission generated by the active ion hosted in it. Nonlinear crystals with suitable sites for lanthanide ions which emit in the infrared region around 1 m may be able to self-double the frequency, i.e. to reduce the wavelength to the half, =500 nm, which is in the blue or green spectral region.
The aim of this doctoral thesis is to synthesize and characterize the type III double phosphate of potassium and gadolinium, KGd(PO3)4 (KGP), either undoped or doped ordoped with ytterbium or neodymium, both of them emitting in the 1 m region.
The KGP crystal is noncentrosymmetric, so with the indispensable requirement to have nonlinear optical properties. We propose to use this crystal as a nonlinear host for alternatively ytterbium (Yb3+) or neodymium (Nd3+) to develop a new promising selffrequency doubling laser crystal to generate blue-green laser radiation.
As double phosphates of potassium and lanthanide melt incongruently, i.e. they decompose before melting, a high-temperature solution growth method has to be used to growth the crystals. This kind of growth methods allows growing the crystal under its melting point and so avoiding its decomposition. We use the top seeded solution growth-slow cooling (TSSG-SC) to grow the undoped and Yb- or Nd-doped KGP single crystals. This kind of growth method allows to freely growing the crystals in the solution by slowly cooling its temperature from the crystallization temperature. It allows obtaining bulk crystals with freely developed crystallographic forms determined by the crystals structure. By optimizing the growth process, we have successfully grown macrodefect-free crystals large enough for later characterizations and possible final application. The crystals have been structurally, physically, optically and spectroscopically characterized. Finally, laser operation with Yb:KGP has been proved for the first time. Although the low ion doping level in the crystal, the rather high slope efficiency obtained with this first sample is rather promising for the future.
In conclusion, single crystals of Yb:KGP and Nd:KGP can be regarded as a promising candidates to be applied as a self-frequency doubling crystals since it has been proved both the second harmonic generation ability and the laser operation.
Milliasseau, Damien. "Synthèse et évaluation physico-chimique de tensioactifs biodégradables et éco-compatibles à partir de pectines pour l’industrie routière." Rennes, Ecole nationale supérieure de chimie, 2016. http://www.theses.fr/2016ENCR0034.
Montes, Thisien Gabriel 1988. "Caracterização experimental de fibras de vidro telurito dopado com érbio e itérbio : Experimental characterization of tellurite glass fibers doped with erbium and ytterbium." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261920.
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: Com a demanda por comunicação continuamente aumentando nos últimos anos, mantém-se constante a busca por aperfeiçoamento dos amplificadores ópticos a fibra. Como uma proposta de proporcionar maior largura de banda de amplificação para sistemas ópticos, este trabalho procura caracterizar o comportamento operacional de uma fibra de vidro telurito dopado com érbio e itérbio para diferentes condições iniciais de comprimento de amostra, aplicação de sinais e configuração de bombeio. As amostras, fabricadas pelo Grupo de Fibras Ópticas do IFGW/UNICAMP, foram submetidas a análises experimentais baseadas nas principais topologias de amplificadores a fibra que usam matrizes de sílica. Assim, avalia-se a potencialidade das características de amplificação do vidro telurito fabricado com dosagem de compostos inéditos, além de uma investigação da possibilidade da geração laser utilizando-se essa fibra como meio ativo em configurações com laço de realimentação. Mesmo que o ganho real do sistema não tenha sido determinado pela incerteza em relação a real potência óptica acoplada às amostras, observou-se ser possível a compensação da atenuação que o sinal que se propaga pelas amostras sofre após a aplicação de bombeio. Nesse aspecto, o vidro telurito dopado com érbio e itérbio apresentou potencial de aplicação em amplificação óptica. Uma amostra de 2 cm, comprimento muito menor que o usado em amplificadores ópticos baseados em matrizes de sílica e uma ordem de grandeza menor que os baseados em vidro telurito dopado apenas com érbio, apresentou resultados de ganho óptico on-off da ordem de 30 dB com bombeio bi-direcional de 100 mW. Em relação ao vidro telurito dopado apenas com érbio, os resultados para o ganho on-off chegaram a ser até 15 dB maiores. Além disso, as transições providas pela interação entre a matriz vítrea com o érbio e o itérbio levaram a larguras de banda de 3 dB para o espectro de ASE de até 70 nm, dependendo da configuração de bombeio
Abstract: With the recently increase in data transmission demands, the search for improved fiber amplifier physical processes, materials, and configurations is still on going. As a way to provide a wider amplification bandwidth for optical systems, this work intends to characterize the operational behavior of an erbium and ytterbium doped tellurite fiber for different sample lengths, light coupling and pump configurations. The fiber samples, manufactured by the Optical Fiber Group of the IFGW/UNICAMP, underwent experimental analyses based on the same main pump topologies as those of silica-based optical amplifiers. Thus, the potential amplification characteristics of tellurite glass doped with new compounds are evaluated, as well as an investigation of possible laser generation by using this type of fiber as gain medium within feedback loop configurations. Although real system gain was impossible to determine due to uncertainties in the actual coupled optical power, it was observed that the attenuation during signal propagation through the fiber samples could be compensated after pump application. In this context, the erbium and ytterbium doped tellurite fiber has potential for optical amplification. Samples as short as 2 cm, far shorter than the ones used in silica based amplifiers and one order of magnitude shorter than those based on Er3+ doped tellurite fiber structures, presented on-off optical gain of the order of 30 dB for bi-directional 100-mW pump. By comparing with the latter doped glass structure, the on-off gain results were as high as 15 dB greater. Furthermore, the transitions provided by the interaction between the host glass and both erbium and ytterbium have led to a 70-nm ASE bandwidth, depending on the pumping configuration
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Mestre em Engenharia Elétrica
Gurgel, Diêgo Pires. "Estudo e desenvolvimento de material absorvedor de micro-ondas baseado em Nb2O5 com mo via metalurgia do pó." Universidade Federal Rural do Semi-Árido, 2016. http://bdtd.ufersa.edu.br:80/tede/handle/tede/718.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In Brazil are located the two largest niobium reserves of the world – about 96% of the world production – and, for this reason, have been encouraged studies on its most diverse technological applications. Another aspect of prominent studies is currently the processing of ceramic materials with a microwave, which is presented as an alternative method of sintering in a muffle furnace – the use of microwave involves electromagnetic energy conversion instead of heat transfer, offering advantages when used for providing the obtainment of greater structural homogeneity of the material and a reduction of time and energy expended during processing. This work aims to perform the characterization of electrical properties of niobium pentoxide (Nb2O5) pure or doped with molybdenum (Mo) and to do an analysis of the influence of this doping when its sintering process occurs in muffle furnace or microwave. The properties characterized were the permittivity and loss tangent. Will be studied the viability of doping and/or processing the material for use as absorbent materials of electromagnetic radiation. The variation of concentrations in doping will indicate how effective, as a doping agent, molybdenum will be in the ceramic matrix, converting energy of microwave into heat energy. The results showed that the increase of doping of the niobium pentoxide with molybdenum (with 1% doping limit) combined with the sintering oven microwave increased the material conductivity values, making it more efficient in its use as absorber electromagnetic radiation
No Brasil estão localizadas as duas maiores reservas de nióbio do mundo – cerca de 96% da produção mundial –, e, por esta razão, têm sido incentivados os estudos sobre as suas mais diversas aplicações tecnológicas. Outra vertente de estudos em destaque atualmente é a do processamento de materiais cerâmicos com micro-ondas, que se apresenta como um método alternativo à sinterização em forno mufla – o uso de micro-ondas envolve conversão de energia eletromagnética, em lugar de transferência de calor, oferecendo vantagens ao ser usado por proporcionar a obtenção de uma maior homogeneidade estrutural do material e uma redução do tempo e da energia gasta durante o processamento. A proposta deste trabalho é a realização da caracterização de propriedades elétricas do pentóxido de nióbio (Nb2O5) puro ou dopado com molibdênio usando a tecnologia da metalurgia do pó e a análise da influência sobre estas dopagens quando seu processamento de sinterização se dá em forno mufla ou em forno de micro-ondas. As caracterizações feitas foram das propriedades elétricas de permissividade elétrica e tangente de perdas além de ter sido estudada a viabilidade da dopagem e/ou o tipo de processamento – na etapa de sinterização – do material para aplicação como materiais absorvedores de radiação eletromagnética. A variação das concentrações nas dopagens indicou o quão eficaz, como agente dopante, o molibdênio será na matriz cerâmica, convertendo a energia de micro-ondas em energia térmica. Os resultados mostraram que o aumento da dopagem do pentóxido de nióbio com molibdênio (com limite de dopagem de 1%) aliado à sinterização em forno de micro-ondas garantiu o aumento dos valores de condutividade do material, tornando-o mais eficiente para sua aplicação como absorvedor de radiação eletromagnética
2017-05-26
El, Masloumi Mohamed. "Photoluminescence et cristallochimie des polyphosphates de formule Na1-xAgxM(PO3)4 (M : la, Y) à l’état cristallisé ou vitreux." Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13727/document.
This work focuses on keeping with the general pattern of investigations of physical-chemical properties of silver-polyphosphates to find new ways for devices such as lighting, visible range laser applications and radiophotoluminescence. The goal of this study aims at understanding the processes of Ag+ luminescence in Na1-xAgxLn(PO3)4 (Ln = La et Y) compounds which structure has been completely determinated. The luminescence of the single crystals is induced by Ag+ ions in isolated sites and close to hole centers (Ag2+) resulting in UV photosensitivity for the lanthanum crystals. The photoluminescence of the Na1-xAgxLa(PO3)4 glasses (glass-forming only) has been resolved owing to UV irradiation investigations and comparison with the luminescence of Na2-xAgxZnP2O7 glass. Both are also due to Ag+ ions in isolated sites
Lima, Amanda Barbosa. "Determina??o de Verapamil e Oxcarbazepina em amostras de urina e formula??es farmac?uticas por amperometria pulsada em FIA." UFVJM, 2016. http://acervo.ufvjm.edu.br/jspui/handle/1/1310.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Verapamil (VP) e Oxcarbazepina (OX) s?o f?rmacos de baixo ?ndice terap?utico que necessitam de rigoroso controle de qualidade em formula??es farmac?uticas, bem como de an?lises em fluidos biol?gicos para estudos farmacol?gicos de elimina??o dessas drogas. Neste sentido, o desenvolvimento de m?todos simples, r?pidos e de baixo custo ? de extrema import?ncia para quantifica??o desses f?rmacos nessas amostras. Deste modo, o presente trabalho apresenta um m?todo eletroanal?tico em fluxo para determinar VP e OX tanto em formula??es farmac?uticas, quanto em amostras de urina. A t?cnica eletroqu?mica utilizada para quantifica??o foi a Amperometria de M?ltiplos Pulsos (MPA) acoplada a um sistema de an?lise por inje??o em fluxo (FIA), utilizando o diamante dopado com boro (BDD). Foram aplicados tr?s pulsos de potencial pela MPA para determina??o do VP em meio de ?cido sulf?rico 0,1 mol L-1, sendo +1,6 V para a oxida??o e, posteriormente, +0,2 V para redu??o do produto gerado do VP e +0,1 V para a limpeza do eletrodo de BDD. Para a determina??o de OX, tamb?m foram otimizados tr?s pulsos de potencial em meio de tamp?o acetato 0,1 mol L-1 (pH 4,0), sendo + 1,7 V para a oxida??o da OX e gera??o do produto que foi reduzido em -1,1 V e -1,3 V para a limpeza do eletrodo de BDD. Em ambos os casos, apenas o sinal obtido nos pulsos de potencial de redu??o foram utilizados para quantifica??o dos f?rmacos. As faixas lineares de trabalho obtidas para quantifica??o do VP e da OX foram de 0,8 a 40,0 ?mol L-1 (R= 0,9976) e 2,0 a 80,0 ?mol L-1 (R= 0,9989), respectivamente. Os limites de detec??o foram calculados em 0,16 ?mol L-1 para VP e 0,42 ?mol L-1 para OX. Uma boa repetibilidade foi obtida para 10 an?lises consecutivas desses f?rmacos, com desvio padr?o relativo de 2,2% para VP e 0,94 % para OX. Os estudos de adi??o e recupera??o do VP e OX em amostras farmac?uticas e urina apresentaram resultados pr?ximos a 100% e o doseamento do VP foi validado pela metodologia oficial. Altas frequ?ncias anal?ticas foram alcan?adas pelo sistema FIA com 45 e 65 determina??es por hora de VP e OX, respectivamente, usando al?as de amostragem inferiores a 200 ?L e vaz?es de 3,5 mLmin-1. An?lises desses f?rmacos em amostras de urina mostraram que ? poss?vel determin?-los mesmo na presen?a de altas concentra??es de ?cido asc?rbico e ?cido ?rico. Portanto, o m?todo proposto mostrou-se como alternativa simples e r?pida para quantifica??o desses f?rmacos em formula??es farmac?uticas e urina.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2016].
Verapamil (VP) and Oxcarbazepine (OX) are drugs of narrow therapeutic index that require strict quality control in pharmaceutical formulations and analysis in biological fluids for pharmacological studies of elimination of these drugs. In this sense, the development of simple, fast and low-cost methods is very important to quantify these drugs in pharmaceutical samples. Therefore, this work presents a electroanalytical method in flow for determining VP and OX in pharmaceutical formulations and human urine samples. The electrochemical technique used for quantification was performed by multiple pulses amperometry (MPA) coupled to a flow injection analysis system (FIA), using boron-doped diamond (BDD) as working electrode. Were applied three potential pulses by MPA for the determination of VP in sulfuric acid 0.1 mol L-1: (1) +1.6 V for oxidation of VP, (2) +0.2 V for reduction of the generated product of VP in the fisrt potential pulse, (3) +0.1 V for cleaning of the BDD electrode surface. The determination of OX also was performed by MPA in three potential pulses in 0.1 mol L-1 acetate buffer (pH 4.0): (1) +1.7 V for oxidation of OX and generation of the product that it was reduced at (2) -1.1 V, and (3) -1.3 V for cleaning of the BDD electrode surface. In both cases, only the signal obtained in the reduction potential pulses were used for quantification of drugs. The linear ranges of work obtained for quantitation of VP and OX were 0.8 to 40.0 ?mol L-1 (R = 0.9976) and 2.0 to 80.0 ?mol L-1 (R = 0, 9989), respectively. The detection limits were calculated to be 0.16 ?mol L-1 for VP and 0.42 ?mol L-1 for OX. Good repeatabilities were obtained for 10 consecutives injections of these drugs, with relative standard deviation of 2.2% for VP and 0.94% for OX. The addition and recovery studies for VP and OX in pharmaceutical and urine samples were close to 100% and determination of VP was validated by the official methodology. High analytical frequencies were achieved by FIA system of 45 and 65 determinations per hour for VP and OX, respectively, using sampling handles less than 200 ?L and flow rate of 3.5 mLmin-1. The analysis of these drugs in urine showed that it is possible to determine this sample even in the presence of high concentrations of ascorbic acid and uric acid. Therefore, the present method by MPA-FIA proved to be a quick and easy alternative to quantify VP and OX in pharmaceutical formulations and urine.
Книги з теми "Doped POT":
Holtry, Mercedez. That Poet is Dope: A collection of poetry by Albuquerque youth. Independently published, 2020.
Journals, Dope. One Dope Log for Health and Healing: Track, Remember, and Recall Your Marijuana, Cannabis, Weed, and Pot Usage for Medical and Recreational Purposes. Independently Published, 2019.
Koh, Harold Hongju. What’s at Stake. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190912185.003.0007.
Wam, Tam. Cannabis Collection Little Black Book Series: A Little Black Book of Mary Jane, a Reefer Keeper, Pot Planner, Joint Journal, Dope Diary, Bud and Blunts Book, That Oooh Wee Organizer, That Good Good Tracker. Independently Published, 2021.
Частини книг з теми "Doped POT":
Melcher, C. L., and J. S. Schweitzer. "Cerium-doped lutetium oxyorthosilicate: a fast, efficient new scintillator." In PET in Clinical Oncology, 85–91. Heidelberg: Steinkopff, 2000. http://dx.doi.org/10.1007/978-3-642-57703-1_8.
Carrasco, I., K. Bartosiewicz, F. Piccinelli, M. Nikl, and M. Bettinelli. "5d-4f Radioluminescence in Pr3+-doped K3YxLu1-x (PO4)2." In NATO Science for Peace and Security Series B: Physics and Biophysics, 489–90. Dordrecht: Springer Netherlands, 2017. http://dx.doi.org/10.1007/978-94-024-0850-8_45.
Liu, Jing Jing, Zuo Wan Zhou, Kai Wang, and Yanxia Li. "Preparation and Characterization of Tin Doped Tetra-Pod Shaped Zinc Oxide." In Materials Science Forum, 1161–64. Stafa: Trans Tech Publications Ltd., 2005. http://dx.doi.org/10.4028/0-87849-960-1.1161.
Kook, Yun Ho, Ji Hun Park, Dong Jin Byun, and Joong Kee Lee. "Characteristics of Fluorine-Doped Tin Oxide Thin Films on Poly Ethylene Terephthalate (PET) Substrate." In Materials Science Forum, 949–52. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-431-6.949.
Kováčová, Mária, Eva Špitalská, and Zdenko Špitálský. "Light-Activated Polymer Nanocomposites Doped with a New Type of Carbon Quantum Dots for Antibacterial Applications." In Urinary Stents, 315–24. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-04484-7_25.
Motisuke, M., R. García Carrodeguas, and Cecília A. C. Zavaglia. "Mg-Free Precursors for the Synthesis of Pure Phase Si-Doped α-Ca3(PO4)2." In Bioceramics 20, 199–202. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-457-x.199.
Yan, G., Ya Feng Lu, Y. Feng, Ping Xiang Zhang, L. Zhou, Andre Sulpice, and Eric Mossang. "Effect of Heat Treatment on Superconducting Properties of Pure and Ti, Zr-Doped MgB2 Superconducting Wires Fabricated by In Situ PIT Method." In Materials Science Forum, 1913–18. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-432-4.1913.
Okoth, Kevin Otieno, Ruth Nduta Wanjau, and Maurice Otieno Odago. "Semiconductor Nanocomposites-Based Photoelectrochemical Aptamer Sensors for Pharmaceuticals Detection." In Research Anthology on Synthesis, Characterization, and Applications of Nanomaterials, 685–708. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8591-7.ch030.
Okoth, Kevin Otieno, Ruth Nduta Wanjau, and Maurice Otieno Odago. "Semiconductor Nanocomposites-Based Photoelectrochemical Aptamer Sensors for Pharmaceuticals Detection." In Advances in Environmental Engineering and Green Technologies, 109–32. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1871-7.ch007.
Moulavi, Mansur, and Kaluram Kanade. "Transition Metal Doped Nanocrystalline MgO Catalyzed Green Chemical Synthesis of E-Ethyl Cinnamate Using One Pot Wittig Reaction." In New Innovations in Chemistry and Biochemistry Vol. 6, 24–43. Book Publisher International (a part of SCIENCEDOMAIN International), 2021. http://dx.doi.org/10.9734/bpi/nicb/v6/1673a.
Тези доповідей конференцій з теми "Doped POT":
Irmawati, Yuyun, Edwin M. Mauludi, Fredina Destyorini, Andri Hardiansyah, Haryo S. Oktaviano, Agung Nugroho, and Rike Yudianti. "One-pot synthesis of CoFe alloy supported on N-doped carbon as Pt-free oxygen reduction catalysts." In THE INTERNATIONAL CONFERENCE ON ADVANCED MATERIAL AND TECHNOLOGY (ICAMT) 2021. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0106430.
Sharotri, Nidhi, and Dhiraj Sud. "One pot synthesis of nanosized anion doped TiO2: Effect of irradiation of sound waves on surface morphology and optical properties." In ADVANCED MATERIALS AND RADIATION PHYSICS (AMRP-2015): 4th National Conference on Advanced Materials and Radiation Physics. AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4929292.
Yust, Brian G., Dhiraj K. Sardar, Lawrence C. Mimun, Ajith K. Gangadharan, and Andrew T. Tsin. "Rare Earth doped nanoparticles in imaging and PDT." In SPIE BiOS, edited by Alexander N. Cartwright and Dan V. Nicolau. SPIE, 2013. http://dx.doi.org/10.1117/12.2004939.
Olusoji, Olugbenga J., Wern Kam, Cheng Xin, Michael Martyn, Hwa-Yaw Tam, and Sinead O’Keeffe. "DPDS and BDK doped Fibre Bragg grating sensors for low dose clinical X-ray measurements." In Optical Fiber Sensors. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/ofs.2022.w3.2.
Zhang, Xin X., Antonio G. J. B. Villaverde, Michael A. Bass, G. B. Loutts, and Bruce H. T. Chai. "Spectroscopy and lasing perfomance of Nd3+ doped Ca5(PO4)3F." In OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, edited by Bruce H. T. Chai. SPIE, 1993. http://dx.doi.org/10.1117/12.149285.
Kaneko, H., Y. Naganuma, S. Taku, K. Ouchi, N. Hasegawa, and Y. Tamaura. "Solar H2 Production From a Two-Step Water Splitting Process With Metal (Fe, Ni) Doped Ceria." In ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/es2008-54281.
Mito, Ikuo, та Kenji Endo. "1.48μm and 0.98μm High-Power Laser Diodes for Erbium-Doped Fiber Amplifiers". У Optical Amplifiers and Their Applications. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oaa.1991.wc1.
Morisawa, Masayuki, and Haruyuki Yokomori. "Improvement in the sensitivity of dye-doped POF-type moisture sensor." In 2010 Ninth IEEE Sensors Conference (SENSORS 2010). IEEE, 2010. http://dx.doi.org/10.1109/icsens.2010.5690139.
Zhu, Yanting, Chenxia Li, and Degang Deng. "Temperature sensitive Properties of Eu2+/ Mn2+ Co-doped Ca2Sr (PO4)2." In 2019 18th International Conference on Optical Communications and Networks (ICOCN). IEEE, 2019. http://dx.doi.org/10.1109/icocn.2019.8934125.
Bayramian, Andy, Camille Bibeau, Kathleen Schaffers, Janice Lawson, Chris Marshall, Stephen Payne, and Robert Morris. "Development of ytterbium doped Sr5(PO4)3F for the Mercury Laser Project." In Advanced Solid State Lasers. Washington, D.C.: OSA, 2001. http://dx.doi.org/10.1364/assl.1999.me18.
Звіти організацій з теми "Doped POT":
Wilkins, Justin, Alexandria Barkman, Alexi Meltel, Burton Suedel, and Robert Richmond. Effects of sedimentation on three Hawaiian coral species under laboratory conditions. Engineer Research and Development Center (U.S.), August 2023. http://dx.doi.org/10.21079/11681/47541.