Copper and nickel supported FSM-16 molecular sieves for carbon nanotube production

FSM-16, Cu-FSM-16 and Ni-FSM-16 type folded sheet mesoporous materials has been synthesized by using kanemite and hexadecyltrimethylammonium bromide as a template. 1, 5, 10 wt % Cu and Ni were loaded by simple impregnation method. The X-ray diffraction and N2 sorption characteristics show that the resultant materials has uniform pore structure with hexagonal well ordered arrangement. BET surface area, pore volume nd pore diameters were decreased as the metal loading increased. Carbon nanotubes (CNTs) have been synthesized within the metal trapped channels of the FSM-16 via chemical vapor deposition using acetylene as the hydrocarbon source. The resultant nanotubes were compared under similar reaction conditions and they were characterized by scanning electron microscopy (SEM), Raman Spectroscopy, AFM and TGA

Globalization and human dimension of forced migrants : my kaaba is human

A tese possui um video em anexo, apenas disponível para consulta na biblioteca da FBAUL - COTA CDA 194The purpose of this work is to understand and elucidate the correlation between immigration and globalization by examining cultural dimensions of globalism. As the world gets “smaller” and affected by globalism more and more each day it is important to see the bound of it with our daily lives and refugee crisis. In this dissertation I will examine globalism phenomenon and its relationship with refugee issue meanwhile human dimension of refugees will be the point to be headed. In this context globalism with economical dimensions will be explained, later the cultural dimension will be mentioned with referred to contemporary social-cultural anthropologist Arjun Appadurai’s perspective. While globalism makes people and cultures get close more to each other in a kind of strange way with recent political developments and refugee crisis people tend to forget the uniqueness of humanity and lead towards to more racist policies. Thus, this research includes some papers and books on the related topics of globalization, as much as source to support with philosophical thinking and approach the issue in a human level. In this regard, the humanism understanding of Hajı Bektashi Veli who is as humanist philosopher from Anatolia of 13th century will be referred in the work as supportive perspective. The aim is to visualize the integrity of the cultural dimension of globalization by reconciling it with the human dimension of immigrants. Globalism cannot be considered separated from economical changes in the world. Concordantly, it will be mention the economic dimension of globalism in dissertation, focusing on capitalism and “world system” as an economic theory. After all it will be revealed the relation between cultural impacts of global developments with forced immigrants and refugees. The project is formed in its basis as a documentary film, because, film/video is a powerful visual medium to raise a wide range of repercussions in social and humanitarian contexts, allowing opportunity of expression for filmmaker to make an impact specially in contemporary culture. Documentary as a visual material creates a language to evoke emotions, transmit the sense by letting the audience to be part of moment and feelings. According to American educator, theorist Edgar Dale people remember 10% of what they read, 20% of what they hear, 30% of what they see but 50% percent of what they “see and hear”. (Dale’s Cone of Experience). Documentary film as a medium lets viewer establish more profound bound and deeper engagement with subject. It creates an impact that, writing language cannot do with letters. The viewer looks at the subject's gaze. The audience who has the voice of the subject has the chance to experience the physically inaccessible environment. Furthermore, it can be effective call-to-action and make profound changes in global world. Motivated by the increasing need to provide support to refugee crisis, I sought to work out this dissertation and documentary in order to allow people to see the behind doors of each one and be a part of their struggles. Because the change will only start by being aware and informe

Production of carbon nanotubes over Fe-FSM-16 catalytic material: effect of acetylene flow rate and CVD temperature

In this article, a high-yield synthesis of high-quality CNTs using Fe catalysts trapped within channels of Folded Sheet Mesoporous Materials, FSM-16 by Chemical Vapor Deposition CVD using acetylene as a hydrocarbon source is reported. The effect of reaction temperature and acetylene flow rate on the formation of CNTs was investigated. It was found that the yield, diameter and quality of CNTs synthesized strongly depend on reaction temperature during CVD. The resulting materials were characterized by scanning electron microscopy (SEM), Raman spectroscopy, and thermogravimetric analysis (TGA). Our research found that carbon deposition, diameter and quality of the CNTs strongly depend on CVD temperature. However acetylene flow rate did not have any significant effect on diameter distribution. Raman measurement indicated that the synthesized products were MWCNTs. High-resolution transmission electron micrographs of samples reveal the multilayer sidewalls of individual MWCNTs with a diameter of 40 nm, in which hollow and tubal structures were observed

Production of carbon nanotubes over Fe-FSM-16 catalytic material: effect of acetylene flow rate and CVD temperature

In this article, a high-yield synthesis of high-quality CNTs using Fe catalysts trapped within channels of Folded Sheet Mesoporous Materials, FSM-16 by Chemical Vapor Deposition CVD using acetylene as a hydrocarbon source is reported. The effect of reaction temperature and acetylene flow rate on the formation of CNTs was investigated. It was found that the yield, diameter and quality of CNTs synthesized strongly depend on reaction temperature during CVD. The resulting materials were characterized by scanning electron microscopy (SEM), Raman spectroscopy, and thermogravimetric analysis (TGA). Our research found that carbon deposition, diameter and quality of the CNTs strongly depend on CVD temperature. However acetylene flow rate did not have any significant effect on diameter distribution. Raman measurement indicated that the synthesized products were MWCNTs. High-resolution transmission electron micrographs of samples reveal the multilayer sidewalls of individual MWCNTs with a diameter of 40 nm, in which hollow and tubal structures were observed

Production of carbon nanotubes using Fe-FSM-16, co-FSM-16 and Ni-FSM-16 type mesoporous catalytic materials by chemical vapor deposition

FSM-16 was synthesized and loaded with 2 and 4 wt % Fe, Co, and Ni by impregnation method. These catalytic materials were tested in the production of carbon nanotubes using the CVD method. The synthesized materials were characterized by XRD, 29Si- NMR, N₂ [Nitrogen] physisorption, and SEM-EDS. The effect of metal concentration on structural characteristics of the mesoporous material was studied. XRD results demonstrated that Fe, Co and Ni modified FSM-16 had hexagonal mesoporous structure. However, both XRD and 29Si-NMR characterization proved, as the metal concentration increased, hexagonal mesoporous structure was partially lost. According to BET results, the surface area, pore volume and pore diameter decreased due to metal impregnation. This was an indication of deterioration of silica matrix. SEM results exhibited the morphological differences between FSM-16 and Fe, Co, and Ni modified FSM-16. Effect of experimental parameters such as metal concentration, reaction temperature and acetylene flow rate for CNTs growth were investigated by using Fe-FSM-16, Co-FSM- 16, and Ni-FSM-16. Synthesized CNTs were characterized by SEM, Raman spectroscopy and TGA. It was found that metal concentration (2-4 wt %), and reaction temparature (500-800ºC [degrees Celsius] were critical for CNTs formation. While each catalyst exhibited high production of CNTs at 700ºC [degrees Celsius] ; and, they were inactive at 500ºC [degrees Celsius]. The diameter of CNTs changed with synthesis temperature, in particular the diameter of the CNTs increased with the reaction temperature. Ni-FSM-16 and Co-FSM-16 showed somewhat lower reactivity in formation CNTs with respect to Fe-FSM-16. Among the catalysts, 4 wt % Fe-FSM-16 improved the formation of CNTs. The effect of acetylene flow rate for CNTs diameters which grown on the 4 wt % Fe-FSM-16 was studied. It was observed that acetylene flow rate did not affect on the diameter of the synthesized CNTs significantly. Diameters of CNTs were almost the same, observed to be in the range of 20-35 nm. Raman measurement indicated that the synthesized products were MWCNTs since no SWCNTs characteristic features appeared in the RBM region. The characterization results demonstrated that CNTs formation with high efficiency was performed by using 4 wt % Fe-FSM-16 with 80 mL/min acetylene flow rate at 700ºC [degrees Celsius] for 30 min

Structural parameters for the non-place in Hermes, nove da noite

Hermes, nove da noite is a piece for tenor saxophone with live spatialisation and video by composer João Quinteiro. The piece was written in 2017, in collaboration with the saxophone player and, due to its level of technical exploration of the instrument, has been object of a work in progress, also with the collaboration of the saxophone player between 2017 and 2019, having reached its final version with video only in the beginning of 2022. This piece integrates a group of ten satellites, tangential to the opera Returning, and takes the homonymous poem by José Mário Silva as starting point for its compositional structure through several processes of deterritorialisation that position the character Hermes in the non-place of an ambulance, after an accident. As a depurated piece from an opera, Hermes, nove da noite keeps its autonomy by establishing a direct relationship with the original poetic text and its meta-layers of signification, more than with the scenic action of the libretto. The affirmation of the non-place happens in this piece through a compositional, visual and performative signification of limit states of the body by rupturing the possibility of projecting the assured past in the creation of a predictable future. In this scenario, the common function of the present as mediating element between the “from where to where”, transforms into a vortex that disrupts the linear perception of continuum and creates an absolute present At the structural level, the piece articulates three distinct typologies of approaching the treatment of sound materials, having as its nuclear vectors: A) continuity and discontinuity / contemplative resistance to fixation - the absolute present - composed by the articulation between abstract and absolute durations, both with long notes / multiphonics and through long eight tone melismata that achieve their final contour through a continuous dislocation across the sound space. This typology also integrates vocal sounds by the performer that result from a phonetical depuration of the original text, focused on emphasising guttural elements that portray the characters’ present state; B) continuous sound flow of short and percussive sounds on an absolute pitch is of secondary order - the interrupted past - composed by an exploration of materials with and without the mouthpiece (tongue rams, key clicks, air against the neck, slaps, alla tromba, etc.). These materials occupy the space in a contrasting manner with A, placing in evidence a pointillist and contrapuntal contour between several points of the sound space. The saxophone player disappears as sound source, playing these materials behind a fibreglass structure. The sounding body is absolutely deterritorialized of its origins and is presented only as a “spatial synapses”; C) a profane melody, built upon a Greek tonoi with origin in the Peloponnese region of Mount Kyllini (birthplace of Hermes), which spreads eight tones along a two octave register. The rhythm of these sections is completely fixated and is a direct depuration of readings from the original poem, creating an interstice between the place of the melody and the place of the text. The materials in sections C are the only ones that are not spatialized, having as its singular sound source the saxophone player - the crystallisation of the future that will not become. From a structural standpoint, the five A sections are fixated pillars of return, between which the performer defines the sequence of events by articulating six B material sections and six C material sections. Despite its apparent univocity, materialised by the saxophone as a single sound source, Hermes, nove da noite is a chamber object, fundamental for the fluidity and character of the sound materials, both regarding the place they occupy in space with the live spatialisation and the articulation with the video, not in a co- dependent relation, but as simultaneously inferring elements in a shared performatic space. The present deprived of continuity was, at the same time, a determinant agent in the process of relating Hermes with migrant communities, through collected statements and interviews, and a determining formal element for the conception of both the piece and the video. Hermes, nove da noite acquires its artistic and expressive significance by simultaneously exploring the limits of the body and the mechanisms that resist the crystallisation of perception, both of the audience and the interpreter[s].publishe

Polyacrylonitrile (PAN)/crown ether composite nanofibers for the selective adsorption of cations

In this study, we prepared electrospun polyacrylonitrile (PAN) nanofibers functionalized with dibenzo-18-crown-6 (DB18C6) crown ether and showed the potential of these fibers for the selective recovery of K+ from other both mono- and divalent ions in aqueous solutions. Nanofibers were characterized by SEM, FTIR and TGA. SEM results showed that the crown ether addition resulted in thicker nanofibers and higher mean fiber diameters, in a range of 138 to 270 nm. Batch adsorption experiments were conducted in order to evaluate the potential of the crown ether modified nanofibers as an adsorbent for ion removal. The maximum adsorption capacity of the crown ether modified nanofibers for K+ was 0.37 mmol g−1 and the nanofibers followed the selectivity sequence of K+ > Ba2+ > Na+ ∼ Li+ for single ion experiments. Adsorption of Ba2+ ions onto crown ether-modified nanofiber was examined by XPS and the results confirmed the adsorption of the ion. Mixed ion adsorption experiments revealed competitive adsorption between K+ and Ba2+ ions for the available binding sites. This effect was not observed for the other monovalent ions present in the solution and exceptionally high selectivities for K+ over Li+ and Na+ were obtained. Also the crown ether modified nanofibers exhibited good regeneration properties and a good reusability over multiple consecutive adsorption–desorption cycles. Electrospinning is thus shown to be a very versatile tool to prepare crown ether functional polymer adsorbents for the selective recovery of ions

Autrui

Catálogo publicado por ocasião da exposição decorrida na Casa das Artes do Porto de 3 de Setembro a 26 de Outubro de 2022info:eu-repo/semantics/publishedVersio

Bio-inspired ion selective crown-ether polymer membranes

Development of unctional membranes that are capable of selectively recognizing and transporting ions have key importance for the recovery and separation of specific icons (e.d. K+, Li+, Na+) from multicomponent mixtures. In this thesis, new membrane materials based on crown ether-metal ion host-guest interactions are developed. Crown ethers are widely used as guest molecules for ions and are able to bind selectively specific cationic species.\ud The main focus of this thesis is the direct incorporation of crown ether units into the polymer main chain, as repeating unites, in contrast to the blending of crown ethers with polymers or postfunctionalization of linear polymers. A major disadvantage of the two last options is the lower effectiveness or washing out of the selective crown ether. With the inchain crown ether unites, crown ether polymers show unique membrane functions, i.e. the selective binding of a specific ion to a very high degree of specificity

Co-firing of biomass with coals: part 2. thermogravimetric kinetic analysis of co-combustion of fir (abies bornmulleriana) wood with Beypazari lignite

The combustion of coal and coal/fir (Abies bornmulleriana) wood blends at the proper ratio (20, 40, 50 wt%) was investigated with thermogravimetric analysis (TG). The influence of biomass blends on thermal and kinetic behavior of coal was studied under non-isothermal conditions. The activation energy of the samples was evaluated with the Ozawa–Flynn–Wall model which compares the combustion of these biowastes with coal under non-isothermal conditions. Our research found that blending influences activation energy of coal; moreover, activation energy related to 50 wt% blend was more similar to pure wood combustion than to coal combustion. Therefore, the activation energy profile shifted from 80.6 to 169.3 kJ/mol. The average reaction order of the samples ranged from 0.13 to 0.35