Добірка наукової літератури з теми "Mesoporous structures"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Mesoporous structures".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Статті в журналах з теми "Mesoporous structures"
Wang, Hongjuan, Xuefei Liu, Olena Saliy, Wei Hu, and Jingui Wang. "Robust Amino-Functionalized Mesoporous Silica Hollow Spheres Templated by CO2 Bubbles." Molecules 27, no. 1 (December 22, 2021): 53. http://dx.doi.org/10.3390/molecules27010053.
Повний текст джерелаTao, Yousheng, H. Tanaka, T. Ohkubo, H. Kanoh, and K. Kaneko. "Pore Structures of ZSM-5 Synthesized in the Mesopore Spaces of a Carbon Aerogel." Adsorption Science & Technology 21, no. 2 (March 2003): 199–203. http://dx.doi.org/10.1260/026361703769013925.
Повний текст джерелаPaik, Jong-Ah, Shih-Kang Fan, Chang-Jin Kim, Ming C. Wu, and Bruce Dunn. "Micromachining of mesoporous oxide films for microelectromechanical system structures." Journal of Materials Research 17, no. 8 (August 2002): 2121–29. http://dx.doi.org/10.1557/jmr.2002.0313.
Повний текст джерелаE. Sangok, Faustina, Sabrina M. Yahaya, Izza Taib Nurul, Siti Zaleha Sa'ad, and Nor Fazila Rasaruddin. "Comparison Study of Amino-Functionalized and Mercaptopropyl-Functionalized Mesoporous Silica MCM-41." Advanced Materials Research 550-553 (July 2012): 1603–6. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.1603.
Повний текст джерелаChen, Ai Min, Pei Gu, and Jun Hu. "A New Mesoporous Magnesium Borate Microsphere Synthesized Using Sodium Dodecyl Sulfate as Template ." Advanced Materials Research 486 (March 2012): 260–64. http://dx.doi.org/10.4028/www.scientific.net/amr.486.260.
Повний текст джерелаZhang, Qian, Minying Wu, Yuanyuan Fang, Chao Deng, Hsin-Hui Shen, Yi Tang, and Yajun Wang. "Dendritic Mesoporous Silica Hollow Spheres for Nano-Bioreactor Application." Nanomaterials 12, no. 11 (June 6, 2022): 1940. http://dx.doi.org/10.3390/nano12111940.
Повний текст джерелаSakamoto, Yasuhiro. "Aperiodic Crystals at the Mesoscale." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C892. http://dx.doi.org/10.1107/s2053273314091074.
Повний текст джерелаAvakyants, Lev P., Sergey E. Svyakhovskiy, Artem E. Aslanyan, and Anatoliy V. Chervyakov. "Photoreflectance in Monolayer Mesoporous Silicon Structures." Journal of Russian Laser Research 41, no. 3 (May 2020): 207–14. http://dx.doi.org/10.1007/s10946-020-09866-w.
Повний текст джерелаZha, Zhenlong, Wenjun Zhu, Feng Chen, Junchao Qian, Xiao-Qin Liu, Lin-Bing Sun, Zhengying Wu, and Zhigang Chen. "Facile Synthesis of Co3O4 Nanoparticle-Functionalized Mesoporous SiO2 for Catalytic Degradation of Methylene Blue from Aqueous Solutions." Catalysts 9, no. 10 (September 27, 2019): 809. http://dx.doi.org/10.3390/catal9100809.
Повний текст джерелаDelgado González, Diana Catherine, Andrés Di Donato, Paolo Nicolas Catalano, and Martín Gonzalo Bellino. "Silver Nanoparticle-Based Arrays into Mesoporous Thin Films Structures for Photoelectronic Circuits." Current Nanoscience 15, no. 3 (February 19, 2019): 304–8. http://dx.doi.org/10.2174/1573413714666180716153501.
Повний текст джерелаДисертації з теми "Mesoporous structures"
Atluri, Rambabu. "Novel Syntheses, Structures and Functions of Mesoporous Silica Materials." Doctoral thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-122289.
Повний текст джерелаSun, Zhen Kun. "Rational design of mesoporous materials with Core/shell structures with applications for sustainability." Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26106.
Повний текст джерелаMesoporous materials, especially ordered ones have become ones of great importance nanomaterials, which possess regular, uniform and interpenetrating mesopores in nanoscale. Morphology and texture controls towards mesoporous materials are critical for a variety of practical applications, the ultimate goal of which are the realization of their functional design. Core/shell composite materials are a type of functional hybrid materials which not only possess the properties of the individual components, but also exhibit some new or synergistic effects between the core and the shell. The design of mesoporous materials with unique core/shell configuration and multifunctions to make them successfully applied in practice, should be an important driving force for the continuous development of current material science. This thesis mainly focuses on two aspects: (1) careful design of core/shell structured mesoporous materials in order to solve the problem and difficulty in synthesis, which hinders their further applications and (2) application of mesoporous materials in cyclic CO2 capture to enhance the durability of CO2 sorbents by taking advantage of the core/shell concept. Aiming at the calcium looping cycle, an attractive technology for large-scale CO2 capture, we have prepared novel mesoporous core/shell structured CaO-based sorbents which exhibit highly stable cyclability and excellent attrition-resistance performances, attributed to advantages of both mesoporous materials and unique core/shell configuration. Our fabrication method could easily be realized in large-scale and meet the requirements of circulating fluidized bed reactors. Owing to their high surface energies, metallic nanoparticles normally tend to aggregate together during catalytic reactions, and their separation from a complex heterogeneous system is another obstacle. In this regards, we have demonstrated a facile and versatile synthesis of multicomponent and multifunctional microspheres Fe3O4@C-Pd@mSiO2 with well-defined core/shell structures, confined catalytic Pd nanoparticles and accessible ordered mesopore channels. Recently, various methods have been proposed for coating mesoporous shells on cores by soft-templating process. However, the generated mesopores are usually very small (< 3 nm), which may limit their further applications. In this work, we have accomplished the synthesis of superparamagnetic core/shell structured microspheres possessing an outer shell of ordered mesoporous silica with large pores (4.5 nm) by adopting triblock-copolymer Pluronic P123 as soft-template.
Schmidt, Sonja. "Tuning Mesoporous Silica Structures via RAFT Polymers: From Multiblock Copolymers as new Templates to Surface Modification." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E379-C.
Повний текст джерелаCastro, Alichandra Maria Gonçalves. "Design of multifunctional mesoporous thin films for electronic applications." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/18658.
Повний текст джерелаOs materiais multiferróicos possuem simultaneamente pelo menos duas das três propriedades ferróicas: i) ferroelectricidade; ii) ferromagnetismo; e / ou iii) ferroelasticidade. Estes materiais têm despertado considerável interesse na indústria microeletrónica devido ao seu potencial para serem usados em dispositivos de armazenamento de informação com elevada capacidade e eficiência energética. A constante procura pela redução do tamanho e aumento da funcionalidade dos dispositivos, imposta pela Lei de Moore, exige materiais ferróicos, na forma de filmes finos e multifuncionalidade. Contudo, à medida que a espessura dos filmes diminui, as propriedades ferróicas ficam comprometidas em virtude de constrangimentos provocados pelo substrato ou outros efeitos. Neste contexto, esta tese estuda a possibilidade de utilizar a porosidade em filmes funcionais para criar sistemas compósitos multifuncionais. Assim, desenvolveram-se estratégias para a preparação de filmes de ferroeléctricos, ferromagnéticos e multiferroícos com porosidade uniforme e ordenada. O efeito dessa porosidade foi avaliado nas propriedades físicas locais e macroscópicas. Foram estudados óxidos multimetálicos com estrutura de perovisquite ou de espinela por serem promissores para aplicação em sensores; atuadores; condensadores; memórias; etc. Escolheu-se uma metodologia química em que os filmes são depositados por técnica de mergulho em soluções sol-gel contendo um copolímero em bloco que se organiza espontaneamente conjuntamente com os precursores durante o processo de evaporação. PbTiO3 foi a composição inicialmente escolhida para entender o efeito da nanoporosidade nas propriedades eléctricas locais por ser o material piezoeléctrico protótipo que possui o mais alto coeficiente piezoeléctrico conhecido. Assim, foram preparados filmes nanoporosos e densos de PbTiO3 com espessura de cerca de 100 nm e diâmetro de poro na ordem dos 50 nm. A presença da nanoporosidade contribui para a cristalização precoce da fase cristalina por aumento local da temperatura durante a decomposição do copolímero e / ou por funcionarem como núcleos de cristalização. Consequentemente, os fimes porosos exibem melhores coeficientes piezoeléctricos e baixo campo coercivo, sendo mais fácil inverter a direção da polarização por efeito do campo elétrico. Sendo a porosidade um meio para atingir propriedades melhoradas, esta pode funcionar como uma ferramenta para ajustar as propriedades ferroeléctricas à aplicação desejada. Todos os resultados de PFM foram previstos através de modelação teórica usando o modelo de elementos finitos. Foi também investigada a preparação de filmes porosos de titanado de bário enquanto protótipo de um ferroeléctrico sem chumbo. Neste contexto, foi avaliado o efeito de vários parâmetros, tais como: i) o aquecimento da solução de precursores; ii) adição de precursores inorgânicos / solventes orgânicos; e iii) envelhecimento da solução inicial, na estrutura final dos filmes.Verificou-se que o uso de uma solução fresca de precursores sem qualquer ciclo de aquecimento contribuía para uma melhor organização dos filmes porosos de BaTiO3. Verificou-se também que o tamanho dos blocos num copolímero à base de poliestireno e poli(óxido de etileno) era preponderante para a ordem e microestrutura cristalina dos filmes finais. Copolímeros em bloco com cadeias de bloco mais longas são preferíveis para obter uma estrutura ordenada e aparentemente desempenham um papel na cristalização precoce da fase ferroeléctrica tetragonal, contribuindo para uma melhoria da resposta piezoeléctrica. Em analogia com o PbTiO3, os resultados indicam que nos filmes nanoporosos de BaTiO3, a cristalização ocorre a temperaturas mais baixas do que nos filmes densos. Utilizou-se a deposição electroquímica para inserir nanopartículas metálicas de cobalto dentro dos poros dos filmes de BaTiO3. O carácter multiferróico dos filmes foi constatado através da avaliação nanoscópica das propriedades elétricas e pela medida das propriedades magnéticas macroscópicas à temperatura ambiente. Verificaram-se as dificuldades de conseguir um preenchimento uniforme dos poros e de otimizar a interface entre as duas fases ferróicas. Assim com vista a tentar ultrapassar estas dificuldades, prepararam-se filmes mais finos e em que a porosidade estivesse devidamente organizada, com poros perpendiculares à superfície. Conceberam-se filmes nanotexturados ordenados de óxidos multimetálicos com propriedades ferroelétricas, ferromagnéticas e multiferróicas com espessuras e texturas de dimensão inferior a 100 nm. As composições escolhidas foram PbTiO3, CoFe2O4 e BiFeO3. Os filmes finos porosos nanotexturados PbTiO3 apresentaram a fase cristalográfica tetragonal mesmo em espessuras de filme de 22 nm. Os filmes finos de CoFe2O4 apresentaram uma orientação preferencial no plano e elevadas magnetizações de saturação. Deduziu-se que os filmes teriam uma impureza ferromagnética compatível com uma liga metálica rica em platina. A presença desta impureza não só melhora o desempenho magnético dos filmes mas também fornece uma forte evidência para a potencial aplicabilidade dos filmes de CoFe2O4 como catalisadores para a oxidação de hidrocarbonetos através do mecanismo de Mars-Van-Krevelen. Foram também preparados filmes finos porosos nanotexturados de BiFeO3, com 66 nm de espessura e tamanho médio de diâmetro de 100 nm. Verificou-se o caráter multiferróico destes filmes e mais uma vez a melhoria clara das propriedades eléctricas locais induzida pela porosidade. A estrutura porosa também tem um efeito positivo nas propriedades magnéticas no plano, mostrando uma componente ferromagnética 50% maior que a medida em filmes densos. Verificou-se também que porosidade dos filmes de BiFeO3 pode ter interesse para aplicações fotocatalíticas, conjugando reduzido valor do hiato óptico direto (2.58 eV) com relativamente elevada área porosa (ca. 57 %). Para testar a aplicabilidade dos filmes nanotexturados na construção de um filme multiferróico compósito, uma matriz porosas ferroelétricos (BaTiO3) foi funcionalizada por preenchimento dos poros com nanopartículas ferromagnéticas de níquel. A estratégia de funcionalização dos poros foi a deposição por arrastamento com CO2 supercrítico, seguida de redução da espécie metálica a 250 ºC ativada por etanol. Pequenas nanopartículas de níquel com cerca de 21 nm foram depositadas dentro dos poros da matriz porosa, tendo-se verificado as propriedades estruturais e magnéticas do compósito. Esta tese, provou a adequação desta metodologia química de baixo custo na concepção de materiais multifuncionais, criando novas perspectivas para a indústria da microeletrónica na sua abordagem contínua de redução de tamanho e custo, enquanto aumenta a complexidade de funcionamento.
Multiferroic materials, exhibiting simultaneously at least two of the three ferroic properties: i) ferroelectricity; ii) ferromagnetism; and iii) ferroelasticity, have attracted considerable interest from the microelectronics industry. Due to their potential, these materials can be used in information storage applications with significantly high energetic efficiencies and elevated capacities. During the last decades and owing the increasing need for miniaturization of electronic devices, the ferroic materials, mainly in the format of thin films, have been extensively studied both theoretically and experimentally. However, as the film thickness decreases the ferroics properties progressively decreases due to the in-plane strain relaxation constrained by the substrate or others intrinsic and extrinsic effects. Within this context, here we exploit the role of nanoporosity on local and macroscopic properties of ferroelectrics, ferromagnetic and multiferroics thin films. Although, porosity is normally considered as a defect (or secondary phase) having usually a detrimental effect on the electrical macroscopic response; it can also be regarded as an asset, in terms of: i) density (light weight) and ii) capacity to host other functionality/ies. Oxides with perovskite and spinel structures are promising materials because they possess extraordinarily useful properties namely to be used as piezoelectrics sensors, as ferroelectric actuators, capacitors and memories, in high-strength dielectrics, for ferromagnetics or even multiferroics. Among the bottom-up approaches, the sol-gel method and evaporation-induced self-assembly methodology are the most suitable, low-cost and easy preparation method to prepare nanoporous and nanopatterned thin films of different compositions. PbTiO3 is the chosen composition to understand the role of the nanoporosity on the local electric properties. Thus, nanoporous and dense ferroelectric PbTiO3 thin films with 100 nm and ~ 50 nm pore size formed using a block polymer as a structure-directing agent are prepared. The presence of nanoporosity markedly affects the microstructure, crystallization and ferroelectric film properties. The crystallization of tetragonal phase is enhanced in nanoporous films. It seems that the decomposition of the block-copolymer in porous films triggers the crystallization of the perovskite phase at low temperatures via the local increase of temperature. Moreover, pores may work as initiators of the crystallization. Consequently, nanoporous films with improved tetragonality exhibit enhanced piezoelectric coefficients, switchable polarization and low local coercivity. In fact, the porosity induces instability in the dipole-dipole interactions and consequently the reverse polarization can be favoured for low bias values. By providing a means of achieving enhanced properties, nanoporosity may work as a tool to tune electric properties to the desired ferroelectric application. All the PFM results were supported by theoretical modelling using Finite Element Model. To have a more complete picture of the role of the nanoporosity on the crystallization and electric properties, the procedure is applied to prepare a nanoporous lead-free material, BaTiO3. However, this expantion was not trivial whereas the crystallization temperature of the tetragonal phase necessary for the ferroelectric properties is much higher than the decomposition temperature of the block-copolymer used as template. From this, several parameters such as: heating the solution, addition of inorganic precursors / organic solvent and aging time of solution are studied in order to understand the effect of these on the micellization process and consequently in the final porous BaTiO3 films. Based on the results of this study, for this specific multimetallic oxide system it is preferable to use a very fresh solution, without any heating cycles. In addition, block-copolymers based on polystyrene and poly(ethylene oxide) with different block sizes are used to investigate their influence on the order and crystalline microstructure of the final films. Blocks-copolymers with longer block chains are preferable to get an ordered structure and apparently play a role on the earliest crystallization of the tetragonal ferroelectric perovskite phase, contributing to an enhancement of the piezoelectric response. Similarly to PbTiO3, our results indicate that in nanoporous BaTiO3 films the crystallization occurs as well before in dense films. Moreover, besides providing a means of achieving enhanced properties, nanoporosity may work as a tool to tune electric properties to the desired ferroelectric application. BaTiO3 nanoporous films are tested as a kind of “golf course” full of holes to accommodate ferromagnetic particles. In this way, electrochemical deposition is used to insert the cobalt metal nanoparticles into the pores of BaTiO3 films. Films containing cobalt particles within the pores are obtained and piezoelectric and ferromagnetic properties are evaluated. For many applications would be a challenge to prepare ferroelectric thin films with lateral sizes well below 100 nm. Furthermore, the design of nanofeatures, uniformed in size and shape at a reasonable large-range order, i.e. “nanopatterning”, would extend their utility for electronic devices and integrated circuits, which require that each pixel feature can be individually addressable. Additionally, nanopatterned porous ferroelectric thin films may be interesting to develop vertical composite structures with perfect strain coupling at the interface. Thus, and using the chemical self-assembly method, different functional nanopatterned porous thin films: PbTiO3, BiFeO3 and CoFe2O4 are designed. Nanopatterned PbTiO3 thin films display the tetragonal ferroelectric crystallographic phase even when the films are as thin as 22 nm. CoFe2O4 thin films present a preferential in-plane orientation. High saturation magnetizations (close or even higher than in bulk CoFe2O4) are determined in all films, pointing to the presence of a ferromagnetic impurity compatible with a platinum-rich metal alloy. The presence of this impurity not only enhances the magnetic performance but also provides evidence for the catalytic activity of these CoFe2O4 films for hydrocarbon oxidation through a Mars-Van-Krevelen mechanism. For the BiFeO3 composition, crystalline nanopatterned BiFeO3 layers with 66 nm of thickness and average pore diameter of 100 nm at 600 ºC are obtained. The large vertical porosity markedly enhances the local electric and macroscopic magnetic properties when compared with the dense counterparts. The porous structure also has a positive effect on the parallel magnetic characteristics of the system, displaying a 50% larger ferromagnetic component and enhanced remanent magnetization when compared to the dense thin films counterpart. The porosity is also important for the photocatalytic applications conjugating the smallest direct band gap (2.58 eV) and extended porous area (ca. 57 %). The nanopatterned thin films allow the exploitation of a new concept to prepare multiferroic nanocomposite thin films. The multiferroic films based on in two chemical-based bottom-up steps, including: i) the formation of a porous ferroic matrix and ii) the accomodation of nanoparticles from another ferroic phase within the pores. Hexagonal-arranged pores with diameter of ca. 95 nm, running perpendicularly to the substrate are filled with nickel nanoparticles using the supercritical fluid deposition technique from reduction of hydrated nickel nitrate in a supercritical CO2-ethanol mixture at 250 ºC. Small nickel nanoparticles with ca. 20 nm are deposited inside the pores of the porous matrix. Structural and magnetic properties proved the coexistence of both phases. The chemical based methodology offers thus an excellent control of the physical and chemical properties of nanostructured materials such as: stoichiometry, thickness, size, array and porous distribution. Moreover the self-assembly of block-copolymers provides a versatile platform to prepare functional nanostructured materials, namely mesostructured oxide thin films, due to their capability to form large pores and thick walls, apart from being industrially available and hazard-free. Additionally, the chemical-assembly method can allow the direct nanopatterning of large substrate areas with a functional oxide at a cost-effective price, in the absence of expensive equipment or etching processes (which typically affect negatively the ferroic properties).Besides, the functional properties of the porous films by themselves, the porous films are extremely promising to achieve multiferroic composites.
Moushey, Douglas Lee. "Formation of Mesoporosity in Zeolite and Mesoporous Molecular Sieve Structures through use of Carbon as a Secondary Templating Agent." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1218657179.
Повний текст джерелаGrudzien, Rafal M. "Synthesis and characterization of ordered cage-like siliceous mesostructures with organic pendant and bridging groups." [Kent, Ohio] : Kent State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1226507948.
Повний текст джерелаTitle from PDF t.p. (viewed Dec. 17, 2009). Advisor: Mietek Jaroniec. Keywords: mesoporous, FDU-1, SBA-16, organosilicas, pendant groups, bridging groups, adsorption, isocyanurate, template removal, cage-like structures. Includes bibliographical references (p. 219-238).
Muroyama, Norihiro. "Studies of inorganic crystal structures and gas adsorption process in mesoporous crystals : new approach through analysis of electron charge distribution by synchrotron powder X-ray diffraction /." Stockholm : Department of Physical, Inorganic and Structural Chemistry, Stockholm university, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7367.
Повний текст джерелаFREIRE, Vitória de Andrade. "Desenvolvimento de material micro-mesoporoso do tipo MCM-22/MCM-41: sítese e caracterização." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/297.
Повний текст джерелаMade available in DSpace on 2018-03-19T16:09:58Z (GMT). No. of bitstreams: 1 VITÓRIA DE ANDRADE FREIRE - DISSERTAÇÃO PPGEQ 2016..pdf: 2687690 bytes, checksum: 093bc81d91144a15964f2333d08a5c8f (MD5) Previous issue date: 2016-04-29
Capes
A pesquisa no desenvolvimento de estruturas do tipo micro-mesoporosas tem por intuito a obtenção de materiais porosos com características superiores, uma vez que busca unir a ácidez elevada da zeólita MCM-22, com o sistema de mesoporos, da peneira molecular MCM-41, consequentemente melhorar a difusão de moléculas volumosas. Nesta pesquisa foram sintetizadas as seguintes estruturas porosas: Inicialmente foi obtido o percussor lamelar MCM22-(P) com razão molar SiO2\Al2O3 = 30 e ativada para obter sua forma zeólítica MCM-22 a 550 0C por 5 horas. Em seguida, foi realizada a síntese do material micro-mesoporoso do tipo MCM-22/MCM-41, tratando 2 g da zeólita MCM-22, com uma solução de 25 mL de brometo de cetiltrimetilamônio (CTABr) a 10 % em massa, onde o material permaneceu em estufa a 1100C por 7 dias. Com o intuito de obter um novo material com melhor organização estrutural, utilizou-se a MCM-22 nas seguintes proporções (5%, 10% e 15%), permanecendo em estufa a 300C por 24 horas, sendo ativado em corrente de ar por 5500C por 5 horas. Os resultados das caracterizações de difratometria de raios-X, evidenciaram a formação do precursor MCM-22 (P) e sua forma zeólítica MCM22, com os picos da topologia MWW. A curvas obtidas por meio da análise termogravimétrica (TG/DrTG), demostraram as perdas de massa da água e demais adsorvatos. As micrografias (MEV), apresentou formato toroidal com depreciamento na região central para a MCM-22. Por meio dos resultados de adsorção física de N2, verifica-se que as zeólitas MCM-22, com isotermas do tipo I e loop de histerese do tipo H4. A partir dos difratogramas de raios - X para os materiais micro-mesoporosos foi possível observar a formação das estruturas porosas, com a identificação dos picos de reflexão pertinentes a fase microporosa da MCM-22 e da peneira molecular MCM-41, coexistindo em uma única fase estrutural. As imagens obtidas por MEV, detectam a formação de aglomerados de partículas da fase mesoporosa sendo constituída em torno da fase microporosa. A análise textural mostraram uma diminuição do volume de microporos e um aumento do volume de mesoporos, com isotermas do tipo IV e histereses 2. Demonstrando assim que as caracterizações foram eficazes na elucidação das estruturas porosas. Foi possível obter os materiais micromesoporosos para ambas as metodologias adotadas, sendo o teor de 5% de zeólita MCM-22 a melhor condição de síntese para obtenção desse novo material.
The research on the development of micro-mesoporous structures has the purpose of obtaining porous materials with superior characteristics, once it seeks to join the high acidity of MCM-22 zeolite with the mesoporous system of MCM41 molecular sieve, consequently improving the diffusion of bulky molecules. In this research, the following porous structures were synthesized: Initially, the MCM-22-(P) lamellar precursor was obtained with molar ratio of SiO2\Al2O3 = 30 and was activated to obtain its MCM-22 zeolite form at 550 °C for 5 hours. Then, MCM-22/MCM-41 micro-mesoporous material was synthesized by treating 2 g of MCM-22 zeolite with a solution of 25 mL of 10% wt cetyltrimethylammonium bromide (CTABr), where the material remained in an incubator at 110 °C for 7 days. In order to obtain a new material with better structural organization, the MCM-22 was used in the following proportions (5%, 10% and 15%), remaining in an incubator at 30 °C for 24 hours, being activated in air stream at 550 °C for 5 hours. The results of the X-ray diffraction characterization demonstrated the MCM-22 (P) precursor formation and its MCM-22 zeolite form, with MWW topology peaks. The curves obtained by means of the thermogravimetric analysis (TG/DrTG), showed the losses of water mass and other adsorbates. The micrographs (SEM) presented toroidal format with depreciation in the central region for MCM-22. By means of the results of physical adsorption of N2, it was verified for MCM-22 zeolites: type I isotherms and hysteresis loops of type-IV. From the X-ray diffractograms for the micro-mesoporous materials, it was possible to observe the formation of the porous structures, with the identification of the reflection peaks pertinent to the microporous phase of MCM-22 and the MCM-41 molecular sieve, coexisting in a single structural phase. The SEM images detected the formation of particle agglomerates of the mesoporous phase being constituted around the microporous phase. The textural analysis showed a decrease in the volume of micropores and an increase in the volume of mesopores, with type IV isotherms and hysteresis loops of type-II. Thus demonstrating that the characterizations were effective in elucidating the porous structures. It was possible to obtain the micro-mesoporous materials for both methodologies, being the 5% content of MCM-22 zeolite the best synthesis condition to obtain this new material.
Schmidt, Sonja Verfasser], Philipp [Akademischer Betreuer] Vana, Philipp [Gutachter] Vana, Marcus [Gutachter] Müller, Burkhard [Gutachter] Geil, Michael [Gutachter] [Buback, Ricardo [Gutachter] Mata, and Florian [Gutachter] Ehlers. "Tuning Mesoporous Silica Structures via RAFT Polymers: From Multiblock Copolymers as new Templates to Surface Modification / Sonja Schmidt ; Gutachter: Philipp Vana, Marcus Müller, Burkhard Geil, Michael Buback, Ricardo Mata, Florian Ehlers ; Betreuer: Philipp Vana." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://nbn-resolving.de/urn:nbn:de:gbv:7-11858/00-1735-0000-002E-E379-C-7.
Повний текст джерелаSchmidt, Sonja [Verfasser], Philipp [Akademischer Betreuer] Vana, Philipp [Gutachter] Vana, Marcus [Gutachter] Müller, Burkhard [Gutachter] Geil, Michael [Gutachter] Buback, Ricardo [Gutachter] Mata, and Florian [Gutachter] Ehlers. "Tuning Mesoporous Silica Structures via RAFT Polymers: From Multiblock Copolymers as new Templates to Surface Modification / Sonja Schmidt ; Gutachter: Philipp Vana, Marcus Müller, Burkhard Geil, Michael Buback, Ricardo Mata, Florian Ehlers ; Betreuer: Philipp Vana." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1154307611/34.
Повний текст джерелаКниги з теми "Mesoporous structures"
Ruren, Xu, ed. Chemistry of zeolites and related porous materials synthesis and structure. Hoboken, N.J: John Wiley, 2007.
Знайти повний текст джерелаMeeting, on Mesoporous Crystals and Related Nano-Structured Materials (2004 Stockholm Sweden). Mesoporous crystals and related nano-structured materials: Proceedings of the Meeting on Mesoporous Crystals and Related Nano-Structured Materials, Stockholm, Sweden, 1-5 June 2004. Amsterdam, The Netherlands: Elsevier, 2004.
Знайти повний текст джерелаRicher, Roger D. Effect of synthesis conditions on the structure and composition of functional mesoporous silica prepared by non-ionic surfactant assembly. Sudbury, Ont: Laurentian University, Chemistry and Biochemistry Department, 2000.
Знайти повний текст джерелаVaporization Heat and Mass Transfer: In Capillaries and Porous Structures. CRC, 2008.
Знайти повний текст джерелаChemistry of Zeolites and Related Porous Materials: Synthesis and Structure. Wiley-Interscience, 2007.
Знайти повний текст джерелаXu, Ruren, Wenqin Pang, Jihong Yu, Qisheng Huo, and Jiesheng Chen. Chemistry of Zeolites and Related Porous Materials: Synthesis and Structure. Wiley & Sons, Limited, John, 2010.
Знайти повний текст джерелаMesoporous Crystals and Related Nano-Structured Materials, Proceedings of the Meeting on Mesoporous Crystals and Related Nano-Structured Materials. Elsevier, 2004. http://dx.doi.org/10.1016/s0167-2991(04)x8161-1.
Повний текст джерелаTerasaki, Osamu. Mesoporous Crystals and Related Nano-Structured Materials: Proceedings of the Meeting on Mesoporous Crystals and Related Nano-Structured Materials, Stockholm, Sweden, 1-5 June 2004. Elsevier Science & Technology Books, 2004.
Знайти повний текст джерелаTerasaki, Osamu. Mesoporous Crystals and Related Nano-Structured Materials, Volume 148: Proceedings of the Meeting on Mesoporous Crystals and Related Nano-Structured Materials, ... (Studies in Surface Science and Catalysis). Elsevier Science, 2004.
Знайти повний текст джерелаЧастини книг з теми "Mesoporous structures"
Pastore, Heloise de Oliveira, and Dilson Cardoso. "Zeolite Structures of Nanometer Morphology: Small Dimensions, New Possibilities." In Mesoporous Zeolites, 31–78. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527673957.ch2.
Повний текст джерелаKrivovichev, Sergey. "2.Topology of Microporous Structures." In Micro- and Mesoporous Mineral Phases, edited by Giovanni Ferraris and Stefano Merlino, 17–68. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509513-002.
Повний текст джерелаMakovicky, Emil. "11. Micro- and Mesoporous Sulfide and Selenide Structures." In Micro- and Mesoporous Mineral Phases, edited by Giovanni Ferraris and Stefano Merlino, 403–34. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509513-011.
Повний текст джерелаRodríguez-Abreu, Carlos, and Jordi Esquena. "Preparation of Mesoporous Materials with Nonhydrocarbon Surfactants." In Self-Organized Surfactant Structures, 213–38. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527632633.ch11.
Повний текст джерелаVendange, V., and Ph Colomban. "Porous Structures of Sol-Gel Al2O3(-3SiO2) Gels and “Glasses” Infiltrated by Aqueous Solutions." In Multifunctional Mesoporous Inorganic Solids, 339–44. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8139-4_26.
Повний текст джерелаFerraris, Giovanni, and Angela Gula. "3. Polysomatic Aspects of Microporous Minerals – Heterophyllosilicates, Palysepioles and Rhodesite-Related Structures." In Micro- and Mesoporous Mineral Phases, edited by Giovanni Ferraris and Stefano Merlino, 69–104. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509513-003.
Повний текст джерелаZub, Yuriy L. "Synthesis of Functionalized Mesoporous Silicas, Structure of Their Surface Layer and Sorption Properties." In Nanomaterials and Supramolecular Structures, 179–96. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-2309-4_14.
Повний текст джерелаLin, Yu Feng, Chen Chi M. Ma, Yao Yu Lin, Chuan Yu Yen, and Chih Hung Hung. "High Proton-Conducting Sulfonated Poly (Ether Ether Ketone)/ Functionalized Mesoporous Silica Composite Membranes." In Advances in Composite Materials and Structures, 945–48. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-427-8.945.
Повний текст джерелаKorotcenkov, Ghenadii. "Humidity Sensors Based on Metal-Oxide Mesoporous-Macroporous and Hierarchical Structures." In Handbook of Humidity Measurement, 389–405. Boca Raton : CRC Press, Taylor & Francis Group, 2018-[2020]: CRC Press, 2020. http://dx.doi.org/10.1201/9781351056502-25.
Повний текст джерелаIwamoto, Masakazu, Maki Yonemitsu, Hiroyuki Kunishima, Jiro Hirosumi, Nozomu Kita, and Yasuhiro Tanaka. "Asymmetric Oxidation of Sulphide on Metal Ion Planted in Mesoporous MCM-41." In Catalysis by Unique Metal Ion Structures in Solid Matrices, 235–48. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0782-5_15.
Повний текст джерелаТези доповідей конференцій з теми "Mesoporous structures"
Hwang, Junho, and Hirofumi Daiguji. "Proton Transport in Mesoporous Silica SBA-16 Thin Films With Three-Dimensional Cubic Structures." In ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icnmm2013-73112.
Повний текст джерелаHonma, Itaru, and H. S. Zhou. "Synthesis of self-assembled photosensitive molecules in mesoporous silicates." In Smart Structures and Materials '97, edited by Wilbur C. Simmons, Ilhan A. Aksay, and Dryver R. Huston. SPIE, 1997. http://dx.doi.org/10.1117/12.267116.
Повний текст джерелаMiyata, Hirokatsu. "Chemically-Prepared Silica Films with Single Crystalline Mesoporous Structures." In Optical Interference Coatings. Washington, D.C.: OSA, 2007. http://dx.doi.org/10.1364/oic.2007.md1.
Повний текст джерелаBANNAT, INGA, KATRTN WESSELS, TORSTEN OEKERMANN, and MICHAEL WARK. "ELECTRODEPOSITION OF GOLD STRUCTURES IN MESOPOROUS TIO2 SOL-GEL FILMS." In Proceedings of the 5th International Symposium. WORLD SCIENTIFIC, 2008. http://dx.doi.org/10.1142/9789812779168_0055.
Повний текст джерелаHan, Sang-Cheol, Kwang-Min Choi, and Sang-Eon Park. "Facile Synthesis of Mesoporous Silica Nanotubes With Amide Type Surfactant." In ASME 2008 2nd Multifunctional Nanocomposites and Nanomaterials International Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/mn2008-47070.
Повний текст джерелаDaiguji, Hirofumi. "Transport and Adsorption Phenomena in Mesoporous Silica." In ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icnmm2012-73137.
Повний текст джерелаStepanov, A., A. Vosmerikov, K. Zharnov, and L. Korobitsyna. "Micro- and mesoporous zeolites for methane dehydroaromatization and Mo-containing catalysts based on them." In PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS WITH HIERARCHICAL STRUCTURE FOR NEW TECHNOLOGIES AND RELIABLE STRUCTURES 2019. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5132218.
Повний текст джерелаNoma, Takashi, Hirokatsu Miyata, Kazuhiro Takada, and Atsuo Iida. "X-Ray Diffraction Properties of Silica Thin Films Having Single Crystalline Mesoporous Structures." In Optical Interference Coatings. Washington, D.C.: OSA, 2007. http://dx.doi.org/10.1364/oic.2007.fa10.
Повний текст джерелаHopkins, Patrick E., Bryan J. Kaehr, Darren Dunphy, and C. Jeffrey Brinker. "Estimating Density Reduction and Phonon Localization From Optical Thermal Conductivity Measurements of Porous Silica and Aerogel Thin Films." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44137.
Повний текст джерелаDaiguji, Hirofumi, Daisuke Nakayama, Asuka Takahashi, Sho Kataoka, and Akira Endo. "Ion Transport in Mesoporous Silica Thin Films." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44526.
Повний текст джерела