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Full-Text Articles in Nanoscience and Nanotechnology

Surface Modification Of Silver Nanoparticle (Agnp) By Liposomal Encapsulation Mitigates Agnp-Induced Inflammation, Azeez O. Yusef, Alan Casey Jan 2019

Surface Modification Of Silver Nanoparticle (Agnp) By Liposomal Encapsulation Mitigates Agnp-Induced Inflammation, Azeez O. Yusef, Alan Casey

Articles

Silver nanoparticles (AgNP) are widely used in a variety of consumable products as antibacterial to prevent or treat infection. Unfortunately, evidence exits that AgNP induces inflammation which can worsen with repeated human exposure. However, there is little or no research on how to mitigate these adverse effects due to AgNP induced-toxicity. Here, we investigated if surface modification of AgNP by liposomal encapsulation suppresses AgNP-mediated inflammatory responses in THP1 monocytes and THP1 differentiated macrophages (TDM). AgNP was encapsulated in a dipalmitoyl phosphatidyl choline- (DPPC)/cholesterol-based liposome by extrusion through a 100-nm polycarbonate membrane to form Lipo-AgNP. It was found as expected ...


Engineered Nanomaterials And Human Health: Part 1. Preparation, Functionalization And Characterization (Iupac Technical Report), Vladimir Gubala, Linda J. Johnston, Harald Friedrich Krug, Colin J. Moore, Christopher K. Ober, Michael Schwenk, Michel R. Vert Jan 2018

Engineered Nanomaterials And Human Health: Part 1. Preparation, Functionalization And Characterization (Iupac Technical Report), Vladimir Gubala, Linda J. Johnston, Harald Friedrich Krug, Colin J. Moore, Christopher K. Ober, Michael Schwenk, Michel R. Vert

Reports

Research on engineered nanomaterials (ENM) has progressed rapidly from the very early stages of studying their unique, size-dependent physicochemical properties and commercial exploration to the development of products that influence our everyday lives. We have previously reviewed various methods for synthesis, surface functionalization, and analytical characterization of ENM in a publication titled 'Engineered Nanomaterials: Preparation, Functionalization and Characterization'. In this second, inter-linked document, we first provide an overview of important applications of ENM in products relevant to human healthcare and consumer goods, such as food, textiles, and cosmetics. We then highlight the challenges for the design and development of new ...


Engineered Nanomaterials And Human Health: Part 2. Applications And Nanotoxicology (Iupac Technical Report) (Review), Vladimir Gubala, Linda J. Johnston, Harald Friedrich Krug, Colin J. Moore, Christopher K. Ober, Michael Schwenk, Michel R. Vert Jan 2018

Engineered Nanomaterials And Human Health: Part 2. Applications And Nanotoxicology (Iupac Technical Report) (Review), Vladimir Gubala, Linda J. Johnston, Harald Friedrich Krug, Colin J. Moore, Christopher K. Ober, Michael Schwenk, Michel R. Vert

Reports

Research on engineered nanomaterials (ENM) has progressed rapidly from the very early stages of studying their unique, size-dependent physicochemical properties and commercial exploration to the development of products that influence our everyday lives. We have previously reviewed various methods for synthesis, surface functionalization, and analytical characterization of ENM in a publication titled 'Engineered Nanomaterials: Preparation, Functionalization and Characterization'. In this second, inter-linked document, we first provide an overview of important applications of ENM in products relevant to human healthcare and consumer goods, such as food, textiles, and cosmetics. We then highlight the challenges for the design and development of new ...


Advances In Diamond Nanofabrication For Ultrasensitive Devices, Stefania Castelletto, Lorenzo Rosa, Jonathan Blackledge, Mohammed Zaher Al Abri, Albert Boretti Oct 2017

Advances In Diamond Nanofabrication For Ultrasensitive Devices, Stefania Castelletto, Lorenzo Rosa, Jonathan Blackledge, Mohammed Zaher Al Abri, Albert Boretti

Articles

This paper reviews some of the major recent advances in single-crystal diamond nanofabrication and its impact in nano- and micromechanical, nanophotonics and optomechanical components. These constituents of integrated devices incorporating specific dopants in the material provide the capacity to enhance the sensitivity in detecting mass and forces as well as magnetic field down to quantum mechanical limits and will lead pioneering innovations in ultrasensitive sensing and precision measurements in the realm of the medical sciences, quantum sciences and related technologies.


Level Anticrossing Of Impurity States In Semiconductor Nanocrystals, Anvar S. Baimuratov, Ivan D. Rukhlenko, Vadim K. Turkov, Irina Ponomareva, Mikhail Yu Leonov, Tatiana S. Perova, Kevin Berwick, Alexander V. Baranov, Anatoly V. Federov Jan 2017

Level Anticrossing Of Impurity States In Semiconductor Nanocrystals, Anvar S. Baimuratov, Ivan D. Rukhlenko, Vadim K. Turkov, Irina Ponomareva, Mikhail Yu Leonov, Tatiana S. Perova, Kevin Berwick, Alexander V. Baranov, Anatoly V. Federov

Articles

The size dependence of the quantized energies of elementary excitations is an essential feature of quantum nanostructures, underlying most of their applications in science and technology. Here we report on a fundamental property of impurity states in semiconductor nanocrystals that appears to have been overlooked—the anticrossing of energy levels exhibiting different size dependencies. We show that this property is inherent to the energy spectra of charge carriers whose spatial motion is simultaneously affected by the Coulomb potential of the impurity ion and the confining potential of the nanocrystal. The coupling of impurity states, which leads to the anticrossing, can ...


Policy Makers’ Influence On The Emergence Of A New Scientific Discipline: The Case Of Nanotechnology In Ireland, Nicolas Battard Feb 2014

Policy Makers’ Influence On The Emergence Of A New Scientific Discipline: The Case Of Nanotechnology In Ireland, Nicolas Battard

Doctoral

Science has undergone tremendous changes since World War II with the blurring of boundaries between science, government, and industry, as well as the so-called convergence of scientific disciplines. Nanotechnology is an illustrative example of this phenomenon. Boundaries between all these spheres are challenged, renegotiated, and reshaped under the influence of the multiple actors involved. I question here the extent to which nanoscience and nanotechnology (N&N) are emerging as a new scientific discipline under the influence of science and technology policies. With the study of N&N in Ireland from the late 1990s onwards, a focus is placed on both ...


Anti-Bacterial Activity Of Indoor Light Activated Photocatalysts, Suresh Pillai, Michael Seery, Damian Synnott, Stephen Hinder, Georg Michlits Feb 2013

Anti-Bacterial Activity Of Indoor Light Activated Photocatalysts, Suresh Pillai, Michael Seery, Damian Synnott, Stephen Hinder, Georg Michlits

Articles

Nanocrystalline photocatalysts, prepared under ambient conditions using a microwave assisted syn-thesis, show indoor light photocatalytic activity for the degradation of Staphylococcus aureus and Escherichia coli. The zinc sulphide (ZnS) nanomaterials, prepared by a microwave assisted synthesis, are shown to be cubic blende structure with an average crystallite size of 4–6 nm. The anti-bacterial activ-ity of these nanomaterials is investigated under irradiation from a 60 W light bulb and photocatalytic activity is revealed to be due to the defects present in the crystal structure. The ZnS shows anti-bacterial action as both a bacteriostatic and bacteriocidal (88% reduction in the amount ...


Ecotoxicological Assessment Of Silica And Polystyrene Nanoparticles Assessed By A Multitrophic Test Battery, Maria Casado, Ailbhe Macken, Hugh Byrne Jan 2013

Ecotoxicological Assessment Of Silica And Polystyrene Nanoparticles Assessed By A Multitrophic Test Battery, Maria Casado, Ailbhe Macken, Hugh Byrne

Articles

The acute ecotoxicity of different diameters of silica and polyethyleneimine polystyrene (PS-PEI)nanoparticles (NPs)was assessed on a test battery of aquatic organisms representing different trophic levels. Daphnia magna, Thamnocephalus platyurus, Pseudokirchneriella subcapitata and Vibrio fischeri, were employed in a series of standard acute ecotoxicity tests and work was complemented with two cytotoxicological end points on a rainbow trout gonadal cell line (RTG-2). Physico-chemical characterization of the NPs was performed in the different test media employed, using dynamic light scattering (DLS) and zeta potentiometry. In contrast to silica NPs exposure, for which no effect was observed for concentrations up to ...


Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern Oct 2011

Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern

Articles

This technical note describes diagrams of friction factor for pipe flow that have been prepared using, mainly, the equations that Lewis Moody used to prepare his famous diagram in 1944. The preparation of the new diagrams was prompted by the need for vector graphics versions that could be used for teaching purposes and that could be distributed freely to students and others under a Creative Commons Attribution-Share-Alike license. Using a structure very similar to that of Moody's diagram, variants with the Darcy friction factor and the Fanning friction factor have been prepared. In addition, variants have been prepared that ...


Dissemination Strategy For The Nanosafety Cluster 27.09.2011, Extra Deliverable 4.12 .Nanoimpactnet Report, Gordon Chambers, Iseult Lynch, Darren Hart, Nathalie Boschung, Byrony Ross, Sonja Grossberndt Jan 2011

Dissemination Strategy For The Nanosafety Cluster 27.09.2011, Extra Deliverable 4.12 .Nanoimpactnet Report, Gordon Chambers, Iseult Lynch, Darren Hart, Nathalie Boschung, Byrony Ross, Sonja Grossberndt

Reports

So that the widest possible group of European nanosafety stakeholders are able to meet, interact, benefit from the work of NSC project members and work using reproducible methods using the same terms, there must be coordination. The following requirements should be clearly defined in the formulation of all new EC sponsored nanosafety-related projects and should be strongly encouraged in existing NSC projects:


Intracellular Localisation, Geno- And Cytotoxic Response Of Poly N-Isopropylacrylamide (Pnipam) Nanoparticles To Human Keratinocyte (Hacat) And Colon Cells (Sw 480), Pratap Naha, Kunal Bhattacharya, Tiziana Tenuta, Kenneth Dawson, Iseult Lynch, Amaya Gracia, Fiona Lyng, Hugh Byrne Oct 2010

Intracellular Localisation, Geno- And Cytotoxic Response Of Poly N-Isopropylacrylamide (Pnipam) Nanoparticles To Human Keratinocyte (Hacat) And Colon Cells (Sw 480), Pratap Naha, Kunal Bhattacharya, Tiziana Tenuta, Kenneth Dawson, Iseult Lynch, Amaya Gracia, Fiona Lyng, Hugh Byrne

Articles

PNIPAM nanoparticles, with and without a covalentlylinked fluorescent label, were prepared by a free radical polymerisation technique. The cyto and genotoxicity of PNIPAM nanoparticles were analysed in two representative mammalian cell lines, SW480, a colon, and HaCaT, a dermal cell line. Physical characterisation in terms of particle size and zeta potential of the PNIPAM nanoparticles was carried out both in aqueous solution and in the appropriate cell culture media. Uptake and colocalisation of fluorescently labelled PNIPAM nanoparticles was monitored in both cell lines using confocal laser scanning microscopy. Genotoxicity analysis using the Comet assay was performed in both cell lines ...


Optical Limiting Study Of Double Wall Carbon Nanotube-Fullerene Hybrids, Kang-Shyang Liao, Jun Wang, Daniel Fruchtl, Nigel Alley, Enrico Andreoli, Eoghan Dillon, Andrew Barron, Hansoo Kim, Hugh Byrne, Werner Blau, Seamus Curran Apr 2010

Optical Limiting Study Of Double Wall Carbon Nanotube-Fullerene Hybrids, Kang-Shyang Liao, Jun Wang, Daniel Fruchtl, Nigel Alley, Enrico Andreoli, Eoghan Dillon, Andrew Barron, Hansoo Kim, Hugh Byrne, Werner Blau, Seamus Curran

Articles

In order to merge complementary temporal and spatial nonlinear optical characteristics of Fullerene and carbon nanotubes, synthesis of double wall carbon nanotube-Fullerene hybrid was performed by covalently linking DWNT and C60 by amination reaction with polyethylenimine. DWNT-Fullerene hybrids were characterized by thermogravimetric analysis, UV-vis spectroscopy and transmission electron microscopy. Optical limiting performance of DWNT-Fullerene hybrids is superior to those of Fullerenes and SWNTs at the same level (~ 80%) of transmission. Whereas nonlinear scattering is an evident mechanism, reverse saturable absorption from Fullerene moieties has significant contribution. Charge transfer between the DWNT and Fullerene moieties may play an important role of ...


Fourier Transform Infrared Microspectroscopy And Multivariate Methods For Radiobiological Dosimetry, Aidan Meade, Colin Clarke, Hugh Byrne, Fiona Lyng Feb 2010

Fourier Transform Infrared Microspectroscopy And Multivariate Methods For Radiobiological Dosimetry, Aidan Meade, Colin Clarke, Hugh Byrne, Fiona Lyng

Articles

The scientific literature contains an ever-growing number of reports of applications of vibrational spectroscopy as a multivariate non-invasive tool for analysis of biological effects at the molecular level. Recently, Fourier transform infrared microspectroscopy (FTIRM) has been demonstrated to be sensitive to molecular events occurring in cells and tissue after exposure to ionizing radiation. In this work the application of FTIRM in the examination of dose-dependent molecular effects occurring in skin cells after exposure to ionizing radiation with the use of partial least-squares regression (PLSR) and generalized regression neural networks (GRNN) was studied. The methodology is shown to be sensitive to ...


A Comparative Study Of The Interaction Of Different Polycyclic Aromatic Hydrocarbons On Different Types Of Single Walled Carbon Nanotubes, Sourabhi Debnath, Qiaohun Cheng, Theresa Hedderman, Hugh Byrne Jan 2010

A Comparative Study Of The Interaction Of Different Polycyclic Aromatic Hydrocarbons On Different Types Of Single Walled Carbon Nanotubes, Sourabhi Debnath, Qiaohun Cheng, Theresa Hedderman, Hugh Byrne

Articles

A comparative study of the solubilising effect of polycyclic aromatic hydrocarbon (PAHs) on single walled carbon nanotubes (SWCNTs) produced by high pressure decomposition of carbon monoxide (HiPco) and the arc discharge (AD) method has been carried out with the aid of fluorescence and Raman spectroscopy. For this study, polyphenyl and polyacene PAHs of different lengths are used. From the study it has been found that the binding energy of PAHs with AD SWCNTs is the same as that with HiPco SWCNTs. Shorter PAHs molecules better solubilise SWCNTs and in general smaller diameter SWCNTs. Thus, given their smaller diameter profile, significantly ...


Resonant Mie Scattering (Rmies) Correction Of Infrared Spectra From Highly Scattering Biological Samples Analyst, Paul Bassan, Achim Kohler, Harald Martens, Joe Lee, Hugh Byrne, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner Jan 2010

Resonant Mie Scattering (Rmies) Correction Of Infrared Spectra From Highly Scattering Biological Samples Analyst, Paul Bassan, Achim Kohler, Harald Martens, Joe Lee, Hugh Byrne, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner

Articles

Infrared spectra of single biological cells often exhibit the “dispersion artefact” observed as a sharp decrease in intensity on the high wavenumber side of absorption bands, in particular the Amide I band at ~1655 cm-1, causing a downward shift of the true peak position. The presence of this effect makes any biochemical interpretation of the spectra unreliable. Recent theory has shed light on the origins of the ‘dispersion artefact’ which has been attributed to resonant Mie scattering (RMieS). In this paper a preliminary algorithm for correcting RMieS is presented and evaluated using simulated data. Results show that the ‘dispersion artefact ...


An Investigation Of The Rwpe Prostate Derived Family Of Cell Lines Using Ftir Spectroscopy, M. Baker, Colin Clarke, D. Demoulin, J. Nicolson, Fiona Lyng, Hugh Byrne, C. Hart, M. Brown, N. Clarke, P. Gardner Jan 2010

An Investigation Of The Rwpe Prostate Derived Family Of Cell Lines Using Ftir Spectroscopy, M. Baker, Colin Clarke, D. Demoulin, J. Nicolson, Fiona Lyng, Hugh Byrne, C. Hart, M. Brown, N. Clarke, P. Gardner

Articles

Interest in developing robust, quicker and easier diagnostic tests for cancer has lead to an increased use of Fourier transform infrared (FTIR) spectroscopy to meet that need. In this study we present the use of different experimental modes of infrared spectroscopy to investigate the RWPE human prostate epithelial cell line family which are derived from the same source but differ in their mode of transformation and their mode of invasive phenotype. Importantly, analysis of the infrared spectra obtained using different experimental modes of infrared spectroscopy produce similar results. The RWPE family of cell lines can be separated into groups based ...


Ultrasound-Assisted Swnts Dispersion: Effects Of Sonication Parameters And Solvent Properties, Qiaohuan Cheng, Sourabhi Debnath, Elizabeth Gregan, Hugh Byrne Jan 2010

Ultrasound-Assisted Swnts Dispersion: Effects Of Sonication Parameters And Solvent Properties, Qiaohuan Cheng, Sourabhi Debnath, Elizabeth Gregan, Hugh Byrne

Articles

Ultrasonication is widely used for preparing Single-Walled Carbon Nanotube (SWNT) dispersions in different solvent media and it has been shown to play a critical role in dispersing and debundling SWNTs. The strong shear force that can exfoliate the SWNT bundles during sonication comes from cavitation, which entails a process of bubble formation, growth, and collapse. The efficiency of the cavitation process is closely correlated to many solvent parameters, including vapor pressure, viscosity, and surface tension, as well as the sonication frequency, intensity, and time. In this study, SWNTs were dispersed in a range of organic solvents assisted by tip sonication ...


Three Dimensional Collagen Gels As A Cell Culture Matrix For The Study Of Live Cells By Raman Spectroscopy, Franck Bonnier, Aidan Meade, S. Merzha, Peter Knief, Kunal Bhattacharya, Fiona Lyng, Hugh Byrne Jan 2010

Three Dimensional Collagen Gels As A Cell Culture Matrix For The Study Of Live Cells By Raman Spectroscopy, Franck Bonnier, Aidan Meade, S. Merzha, Peter Knief, Kunal Bhattacharya, Fiona Lyng, Hugh Byrne

Articles

Three dimensional collagen gels are evaluated as matrices for the study of live cells by Raman spectroscopy. The study is conducted on a human lung adenocarcinoma (A549) and a spontaneously immortalized human epithelial keratinocyte (HaCaT) cell line. It is demonstrated, using the Alamar Blue assay, that both cell models exhibit enhanced viability in collagen matrices compared to quartz substrates, commonly used for Raman spectroscopy. Using principal component analysis, it is shown that the Raman spectral analysis of cells in collagen matrices are minimally contaminated by substrate contributions and the cell to cell spectral variations are greatly reduced compared to those ...


Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath Jan 2010

Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath

Doctoral

Single-walled carbon nanotubes (SWCNTS) are proposed to be one of the most promising nanomaterials, with unique electronic and mechanical properties which lend themselves to a variety of applications. In all cases the quality of the SWCNT material is important, and for some applications it is paramount. Despite sustained efforts, all currently known SWCNT synthetic techniques generate significant quantities of impurities. They also grow in bundles or ropes and are largely insoluble in common organic solvents. SWCNTS can have a range of structures and their electronic properties (metallic or semiconducting) depend on their structure and as well on their diameters. Currently ...


Reflection Contributions To The Dispersion Artefact In Ftir Spectra Of Single Biological Cells, Paul Bassan, Hugh Byrne, Joe Lee, Franck Bonnier, Colin Clarke, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner Apr 2009

Reflection Contributions To The Dispersion Artefact In Ftir Spectra Of Single Biological Cells, Paul Bassan, Hugh Byrne, Joe Lee, Franck Bonnier, Colin Clarke, Paul Dumas, Ehsan Gazi, Michael Brown, Noel Clarke, Peter Gardner

Articles

Fourier transform infrared spectra of a single cell in transflection geometry are seen to vary significantly with position on the cell, showing a distorted derivative-like lineshape in the region of the optically dense nucleus. A similar behaviour is observable in a model system of the protein albumin doped in a potassium bromide disk. It is demonstrated that the spectrum at any point is a weighted sum of the sample reflection and transmission and that the dominance of the reflection spectrum in optically dense regions can account for some of the spectral distortions previously attributed to dispersion artefacts. Rather than being ...


One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat Jan 2009

One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat

Articles

No abstract provided.


Influence Of Magnesium Nitrate On The Corrosion Performance Of Sol-Gel Coated Aa2024-T3 Aluminium Alloy, Rajath Varma, Brendan Duffy, John Cassidy Jan 2009

Influence Of Magnesium Nitrate On The Corrosion Performance Of Sol-Gel Coated Aa2024-T3 Aluminium Alloy, Rajath Varma, Brendan Duffy, John Cassidy

Articles

Traditional anti-corrosion technology has relied heavily on using reducible metal species, predominantly hexavalent chromium (Cr(VI)), for protecting reactive metal alloys such as aluminium which is extensively used in the aerospace sector. However, the impending changes in the use of Cr(VI) in Europe and the United States have forced aerospace manufacturers to examine alternative materials for protecting aluminium. One of the most promising alternatives being investigated are organosilane based sol-gels containing anticorrosion additives. In this work the anti-corrosion properties of magnesium (II) nitrate (Mg(NO3)2) as a inhibitor was investigated at different concentrations (0.1% - 1.0 wt ...


Preparation, Characterization Of Nipam And Nipam/Bam Copolymer Nanoparticles And Their Acute Toxicity Testing Using An Aquatic Test Battery, Pratap Naha, Alan Casey, Tiziana Tenuta, Iseult Lynch, Kenneth Dawson, Hugh Byrne, Maria Davoren Jan 2009

Preparation, Characterization Of Nipam And Nipam/Bam Copolymer Nanoparticles And Their Acute Toxicity Testing Using An Aquatic Test Battery, Pratap Naha, Alan Casey, Tiziana Tenuta, Iseult Lynch, Kenneth Dawson, Hugh Byrne, Maria Davoren

Articles

Poly N-isopropylacrylamide and N-isopropylacrylamide / N-tert-butylacrylamide copolymer nanoparticles of 50 to 70 nm were prepared by free radical polymerisation. The particle sizes of the copolymer nanoparticles were measured in the test media MilliQ water, Algae Media, Daphnia Media and Microtox Diluent as a function of temperature. Whereas in MilliQ water the particle size was seen to decrease above the lower critical solution temperature of the thermoresponsive polymer, in the test media it was seen to increase significantly, indicative of aggregation. At the temperatures employed for the ecotoxicological studies all particles, with the exception of the 50:50copolymer existed as nanoparticles, however ...


One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat Jan 2009

One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat

Articles

No abstract provided.


The Bundle Dispersion Of Swnt On Interaction With P-Terphenyl, Theresa Hedderman, Anika Mostaert, Anne Shanahan, Hugh Byrne Jan 2009

The Bundle Dispersion Of Swnt On Interaction With P-Terphenyl, Theresa Hedderman, Anika Mostaert, Anne Shanahan, Hugh Byrne

Articles

This paper investigates the interaction and bundle dispersion of single walled carbon nanotubes (SWNT) produced by arc discharge and by the high pressure decomposition of carbon monoxide, often referred to as the HiPco method, in the presence of the molecule p-terphenyl. The study will show that the extent of SWNT bundle dispersion and the degree of interaction with p-terphenyl is related to the level of purity of the SWNT sample. This study compares the bundle dispersion and interaction of SWNT with p-terphenyl in their as produced state and after purification. A number of spectroscopic and microscopic techniques are used to ...


Synthesis Of Maleic Anhydride Grafted Polypropylene-Butadiene Copolymer And Its Application In Pp/Ommt/Sbs Composite As Compatibilizer, Qiaohuan Cheng, Zhanxia Lu, Hugh Byrne Jan 2009

Synthesis Of Maleic Anhydride Grafted Polypropylene-Butadiene Copolymer And Its Application In Pp/Ommt/Sbs Composite As Compatibilizer, Qiaohuan Cheng, Zhanxia Lu, Hugh Byrne

Articles

Maleic Anhydride (MA) grafted propylene-butadiene copolymer (PPB) was prepared. FTIR and 1H-NMR results indicated that the MA molecules reacted with the double bond in the butadiene unit of the PPB and the grafting percentage increased with the butadiene content in the initial copolymer. GPC results showed the introduction of butadiene in the copolymer prevented the degradation of the PPB. The MA-g-PPB (MPPB) was applied in PP/SBS/OMMT composite as compatibilizer. In the presence of 10phr MPPB, the impact strength of the composite was improved by ~20%. XRD patterns indicated the formation of β-phase crystallization of polypropylene in the presence ...


A Simple Sol-Gel Processing For The Development Of High-Temperature Stable Photoactive Anatase Titania, Suresh Pillai, Declan Mccormack, John Colreavy Jan 2007

A Simple Sol-Gel Processing For The Development Of High-Temperature Stable Photoactive Anatase Titania, Suresh Pillai, Declan Mccormack, John Colreavy

Articles

No abstract provided.


Physiochemical Indicators Of Single Walled Carbon Nanotube Toxicity, Alan Casey Jan 2007

Physiochemical Indicators Of Single Walled Carbon Nanotube Toxicity, Alan Casey

Doctoral

Numerous toxicity studies have been conducted to date both in vivo and in vitro on refined and raw Single Walled Carbon Nanotubes (SWCNT). Differences in SWCNT toxicity and biocompatibility have been observed between these studies, and whilst these discrepancies have been attributed to factors such as varying percentages of remnant catalytic particles, differences in dispersion methods etc. the mechanisms underlying these inconsistencies have not been investigated. This study used standard spectroscopic and cellular techniques to elucidate the origins of these inconsistencies and also to estimate the validity of toxicological data evaluated form standard cytotoxic endpoints. Spectroscopic studies were conducted in ...


Microstructural Analysis Of Varistors Prepared From Nanosize Zno, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra Jan 2004

Microstructural Analysis Of Varistors Prepared From Nanosize Zno, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra

Articles

No abstract provided.


The Effect Of Processing Conditions On Varistors Prepared From Nanocrystalline Zno, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra Jan 2003

The Effect Of Processing Conditions On Varistors Prepared From Nanocrystalline Zno, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra

Articles

Nanoparticles of ZnO were prepared by the reaction of ethanolic solutions of zinc acetate and oxalic acid
followed by drying (80 uC) and calcination (500 uC). Subsequently varistor materials were fabricated from this
nanoparticular ZnO via two separate routes:- a) from a ‘‘core shell’’ material using metal salts as additives; b)
by using a conventional solid state mixing of metal oxides. Sintering (1050 uC) and subsequent electrical studies
were carried out for each of these samples and they were compared with commercial varistor samples prepared
under similar conditions. ‘‘Core shell’’ type varistor material showed considerably higher breakdown voltage
(Vc ~ 850 ...