Nanofiltration applications of tough MWNT buckypaper membranes containing biopolymers

© 2017 Elsevier B.V. The ability of biopolymers (bovine serum albumin, lysozyme, chitosan, gellan gum and DNA) to facilitate formation of aqueous dispersions of MWNTs was investigated using a combination of absorption spectrophotometry and optical microscopy. Subsequently, self-supporting carbon nanotube membranes, known as buckypapers (BPs), were prepared by vacuum filtration of the dispersions. Microanalytical data obtained from the BPs confirmed the retention of biopolymers within their structures. Tensile test measurements performed on the BPs showed that incorporation of the biopolymers resulted in significant improvements in mechanical properties, compared to analogous BPs containing MWNTs and the low molecular mass dispersant Triton X-100. For example, MWNT/CHT BPs (CHT=chitosan) exhibited values for tensile strength, ductility, Young's modulus and toughness of 28±2 MPa, 5.3±2.7%, 0.9±0.3 GPa and 1.7±0.3 J g−1, respectively. Each of these values are significantly greater than those obtained for MWNT/Trix BPs, prepared using a low molecular weight dispersant (6±3 MPa, 1.3±0.2%, 0.6±0.3 GPa and 0.10±0.06 J g−1, respectively). This significant improvement in mechanical properties is attributed to the ability of the long biopolymer molecules to act as flexible bridges between the short CNTs. All BPs possessed hydrophilic surfaces, with contact angles ranging from 29±2° to 57±5°. Nitrogen gas porosimetry showed that the BPs have highly porous internal structures, while scanning electron microscopy (SEM) showed their surface morphologies have numerous pore openings. The permeability of the BPs towards water, inorganic salts, and dissolved trace organic contaminants (TrOCs), such as pharmaceuticals, personal care products, and pesticides, was investigated through filtration experiments. Of the twelve TrOCs investigated in this study, nine were rejected by more than 95% by BPs composed of MWNTs and chitosan. The latter BPs also demonstrated good rejection of both NaCl (30–55%) and MgSO4(40–70%)

Bacterial filtration using carbon nanotube/antibiotic buckypaper membranes

The preparation of free-standing carbon nanotube “buckypaper” (BP) membranes consisting of either single-walled carbon nanotubes(SWNTs) or multi-walled carbon nanotubes (MWNTs), and the antibiotic ciprofloxacin (cipro), is reported. The electrical, mechanical and morphological properties of these membranes have been characterised and are compared to those of the corresponding containing the surfactant Triton X-100 (Trix). Analysis of scanning electron microscopic images of the surfaces of SWNT/cipro and SWNT/Trix (Trix = Triton X-100) buckypapers revealed that the diameter of their surface pores was significantly smaller than that of the corresponding materials prepared using MWNTs. Similarly, the average internal pore diameter of both SWNT buckypapers was found to be smaller than that of their MWNT counterparts, after analysis of binding isotherms derived from nitrogen adsorption/desorption measurements performed on the materials. All four buckypaper membranes examined were found to be >99% effective for removing Escherichia coli (E. coli) from aqueous suspensions. However, buckypapers containing ciprofloxacin outperformed their counterparts containing the surfactant. BothMWNT buckypapers were more effective at preventing passage of E. coli than their analogues containing SWNTs, while fluorescence microscopic examination of stained membrane surfaces demonstrated that buckypapers composed of SWNTs had greater bactericidal properties. © 2013, Luke J. Sweetman et al

Pengembangan Sistem Authority Control Terintegrasi Dalam Proses Bisnis Perpustakaan

Authority control  adalah kegiatan menetapkan, membuat, dan menggunakan istilah standar yang dipakai dalam katalog perpustakaan beserta acuannya. Sampai saat ini authority control belum banyak digunakan, padahal  authority control merupakan hal yang penting bagi perpustakaan sebagai bentuk kontrol bibliografi. Oleh karena itulah, perlu dikembangkan sebuah sistem authority control yang efektif, yang dapat dijadikan alat atau sarana bagi pustakawan dalam menentukan keseragaman akses pada katalog sehingga terdapat konsistensi dalam penentuan titik akses informasi dan untuk meningkatkan hasil temu kembali informasi. Rancangan sistem authority control dalam penelitian ini menggunakan metode SDLC (System Development Life Cycle)  yang meliputi studi kelayakan, investigasi sistem,  analisis sistem, desain sistem, implementasi, serta review dan maintenance (Avison dan Fitsgerald (2006). Penelitian ini dilakukan  sampai tahap pembuatan prototipe. Fasilitas yang disediakan dalam rancangan sistem ini adalah fasilitas penelusuran dan input data yang terdiri dari tajuk subjek, tajuk nama pengarang,  dan tajuk badan korporasi.Kata Kunci: Authority Control, Perpustakaan Nasional RI, Titik Akses Informasi, Referensi Silang, Tajuk Subjek, Tajuk Nama Pengarang, Tajuk Badan Korporas

Synthesis, properties and water permeability of SWNT buckypapers

The ability of macrocyclic ligands to facilitate formation of dispersions of single-walled carbon nanotubes (SWNTs) was investigated using a combination of absorption spectrophotometry and optical microscopy. Vacuum filtration of aqueous dispersions containing SWNTs and various macrocyclic ligands (derivatised porphyrin, phthalocyanine, cyclodextrin and calixarene) afforded self-supporting membranes known as buckypapers. Microanalytical data and energy dispersive X-ray spectra were obtained for these buckypapers and provided evidence for retention of the macrocyclic ligands within the structure of the membranes. The electrical conductivities of the membranes varied between 30 ± 20 and 220 ± 60 S cm−1, while contact angle analysis revealed they all possessed hydrophilic surfaces. The mechanical properties of buckypapers prepared using macrocyclic ligands as dispersants were shown to be comparable to that of a benchmark material prepared using the surfactant Triton X-100 (Trix). Incorporation of the macrocyclic ligands into SWNT buckypapers was found to increase their permeability up to ten-fold compared to buckypapers prepared using Trix. No correlation was observed between the water permeability of the membranes and the average size of either their surface or internal pores. However, the water permeability of the membranes was found to be inversely dependent on their surface area

Atomic layer depostion of TiO2/Al2O3 films for optical applications

Atomic layer deposition (ALD) is an important technology for depositing functional coatings on accessible, reactive surfaces with precise control of thickness and nanostructure. Unlike conventional chemical vapour deposition, where growth rate is dependent on reactant flux, ALD employs sequential surface chemical reactions to saturate a surface with a (sub-) monolayer of reactive compounds such as metal alkoxides or covalent halides, followed by reaction with a second compound such as water to deposit coatings layer-by-layer. A judicious choice of reactants and processing conditions ensures that the reactions are self-limiting, resulting in controlled film growth with excellent conformality to the substrate. This paper investigates the deposition and characterisation of multi-layer TiO2 /Al2O3 films on a range of substrates, including silicon , soda glass and polycarbonate, using titanium tetrachloride/water and trimethylaluminium/water as precursor couples. Structure-property correlations were established using a suite of analytical tools, including transmission electron microscopy (TEM), secondary ion mass spectrometry (SIMS), X-ray reflectometry (XRR) and spectroscopic ellipsometry (SE). The evolution of nanostructure and composition of multi-layer high/low refractive index stacks are discussed as a function of deposition parameters

Actividades corporales de aventura en la escuela: la carrera de orientación como propuesta en el desarrollo de habilidades socioemocionales

Os esportes de aventura quando tematizados nas aulas de Educação Física têm o potencial de despertar fortes emoções, principalmente pelas experiências de risco e aventura, no contexto escolar, a Base Nacional Comum Curricular-BNCC, existe há necessidade de se trabalhar a educação emocional. O objetivo deste estudo foi analisar o comportamento socioemocional dos alunos diante de uma intervenção de corrida de orientação. 39 escolares do ensino médio participaram do estudo. Foi aplicado o questionário Big Five Inventory (BFI) após uma intervenção de corrida de orientação para a avaliação do perfil socioemocional. Foi constado que as maiores médias entre os perfis foram: Abertura (34,59), amabilidade (30,44), conscienciosidade (28,23) (tabela 1). A corrida de orientação, se mostra eficaz no desempenho emocional dos escolares pois os perfis de maior as maiores medias foram para os perfis de: Abertura, amabilidade e conscienciosidade. Está intervenção também atende aos requisitos presentes no BNCC sobre o desenvolvimento emocional como também sobre a necessidade de práticas de aventura para a Educação Física.Adventure sports when thematized in Physical Education classes have the potential to arouse strong emotions, mainly through risk and adventure experiences, in the school context, the National Common Curricular Base-BNCC, there is a need to work on emotional education. The objective of this study was to analyze the socio-emotional behavior of students in the face of an orienteering race intervention. 39 high school students participated in the study. The Big Five Inventory (BFI) questionnaire was applied after an orienteering race intervention to assess the socio-emotional profile. It was found that the highest averages among the profiles were: Openness (34.59), kindness (30.44), conscientiousness (28.23) (Table 1). The orienteering race proves to be effective in the emotional performance of the students because the profiles of the highest the highest averages were for the profiles of: Openness, kindness and conscientiousness. This intervention also meets the requirements present in the BNCC on emotional development as well as on the need for adventure practices for Physical Education.Los deportes de aventura cuando son tematizados en las clases de Educación Física tienen el potencial de despertar emociones fuertes, principalmente a través de experiencias de riesgo y aventura, en el contexto escolar, Base Curricular Común NacionalBNCC, existe la necesidad de trabajar la educación emocional. El objetivo de este estudio fue analizar el comportamiento socioemocional de los estudiantes ante una intervención de carrera de orientación. 39 estudiantes de secundaria participaron en el estudio. Se aplicó el cuestionario Big Five Inventory (BFI) después de una intervención de carrera de orientación para evaluar el perfil socioemocional. Se encontró que los promedios más altos entre los perfiles fueron: Apertura (34,59), amabilidad (30,44), escrupulosidad (28,23) (Tabla 1). La carrera de orientación demuestra ser efectiva en el desempeño emocional de los estudiantes debido a que los perfiles de los más altos los promedios más altos fueron para los perfiles de: Apertura, amabilidad y escrupulosidad. Esta intervención también cumple con los requisitos presentes en el BNCC sobre el desarrollo emocional, así como sobre la necesidad de prácticas de aventura para la Educación Física.Facultad de Humanidades y Ciencias de la Educació

Synthesis, properties and water permeability of SWNT buckypapers

The ability of macrocyclic ligands to facilitate formation of dispersions of single-walled carbon nanotubes (SWNTs) was investigated using a combination of absorption spectrophotometry and optical microscopy. Vacuum filtration of aqueous dispersions containing SWNTs and various macrocyclic ligands (derivatised porphyrin, phthalocyanine, cyclodextrin and calixarene) afforded self-supporting membranes known as buckypapers. Microanalytical data and energy dispersive X-ray spectra were obtained for these buckypapers and provided evidence for retention of the macrocyclic ligands within the structure of the membranes. The electrical conductivities of the membranes varied between 30 ± 20 and 220 ± 60 S cm−1, while contact angle analysis revealed they all possessed hydrophilic surfaces. The mechanical properties of buckypapers prepared using macrocyclic ligands as dispersants were shown to be comparable to that of a benchmark material prepared using the surfactant Triton X-100 (Trix). Incorporation of the macrocyclic ligands into SWNT buckypapers was found to increase their permeability up to ten-fold compared to buckypapers prepared using Trix. No correlation was observed between the water permeability of the membranes and the average size of either their surface or internal pores. However, the water permeability of the membranes was found to be inversely dependent on their surface area

Diagnostic accuracy of a clinical diagnosis of idiopathic pulmonary fibrosis: An international case-cohort study

We conducted an international study of idiopathic pulmonary fibrosis (IPF) diagnosis among a large group of physicians and compared their diagnostic performance to a panel of IPF experts. A total of 1141 respiratory physicians and 34 IPF experts participated. Participants evaluated 60 cases of interstitial lung disease (ILD) without interdisciplinary consultation. Diagnostic agreement was measured using the weighted kappa coefficient (\u3baw). Prognostic discrimination between IPF and other ILDs was used to validate diagnostic accuracy for first-choice diagnoses of IPF and were compared using the Cindex. A total of 404 physicians completed the study. Agreement for IPF diagnosis was higher among expert physicians (\u3baw=0.65, IQR 0.53-0.72, p20 years of experience (C-index=0.72, IQR 0.0-0.73, p=0.229) and non-university hospital physicians with more than 20 years of experience, attending weekly MDT meetings (C-index=0.72, IQR 0.70-0.72, p=0.052), did not differ significantly (p=0.229 and p=0.052 respectively) from the expert panel (C-index=0.74 IQR 0.72-0.75). Experienced respiratory physicians at university-based institutions diagnose IPF with similar prognostic accuracy to IPF experts. Regular MDT meeting attendance improves the prognostic accuracy of experienced non-university practitioners to levels achieved by IPF experts

Review of Commercial Electronic Ceramic Materials in Australia; 50 years onwards

This review paper will address the Australian history of electronic ceramic materials which were used primarily for their dielectric properties rather than their insulation properties. The history of these materials can be broken down into three main periods. The first period is that prior to 1950, when the electronic components industry was first set-up. The second period from approximately 1950 to 1975 involves the expansion and decline of the capacitor product lines and production capacity under the Ducon Condenser Company. The third period from approximately 1975 and continuing to the current day, involves the manufacture of piezoelectric components and devices through Ausonics Pty Ltd and a group at Plessey Ducon, which was subsequently managed in turn by its successors, Plessey Australia, GEC Marconi, Thomson Marconi and the Thales Australia companies. ©2014, The Australian Ceramic Societ