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Full-Text Articles in Physical Sciences and Mathematics

A Simple Inexpensive Method For The Rapid Testing Of The Photocatalytic Activity Of Self Cleaning Surfaces, Andrew Mills, James Hepburn, David Hazafy, Christopher O'Rourke, Josef Krysa, Michal Baudys, Martin Zlamal, Hana Bartkova, Claire Hill, Kim Winn, Morten Simonsen, Erik Sogaard, Suresh Pillai, Nigel Leyland, Rachel Fagan, Frank Neumann, Christina Lampe, Tobias Graumann Nov 2013

A Simple Inexpensive Method For The Rapid Testing Of The Photocatalytic Activity Of Self Cleaning Surfaces, Andrew Mills, James Hepburn, David Hazafy, Christopher O'Rourke, Josef Krysa, Michal Baudys, Martin Zlamal, Hana Bartkova, Claire Hill, Kim Winn, Morten Simonsen, Erik Sogaard, Suresh Pillai, Nigel Leyland, Rachel Fagan, Frank Neumann, Christina Lampe, Tobias Graumann

Articles

A rapid semi-quantitative, inexpensive method,using a simple digital scanner and an indicator ink, suitable for use in the laboratory, or in the field, for assessing the photocatalytic activity of commerical photocatalytic self-cleaning materials such as glass, is described. The repeatability of the current method is found to be hight and better than many of the previously reported ISO photocatalyst tests.


Synthesis Of Orthogonally Protected 1,2-Diaminopropanoic Acids By Ring-Opening Of 3-Unsubstituted N-Activated Aziridine 2-Carboxylates With Para-Methoxybenzylamine: A Study Of The Regioselectivity Of The Reaction, Fintan Kelleher, Keith O'Brien Oct 2013

Synthesis Of Orthogonally Protected 1,2-Diaminopropanoic Acids By Ring-Opening Of 3-Unsubstituted N-Activated Aziridine 2-Carboxylates With Para-Methoxybenzylamine: A Study Of The Regioselectivity Of The Reaction, Fintan Kelleher, Keith O'Brien

Articles

Orthogonally protected 1,2-diaminopropanoic acids (DAPs) have been synthesised in good yields by the ring-opening of 3-unsubstituted N-activated aziridine 2-carboxylates with para-methoxybenzylamine. The choice of both the N-activating group and ester alkyl group had a significant influence on the ratio of attack at the a or b positions of the aziridine. However, the regiochemical outcome is not predictable.


Novel Microwave Assisted Synthesis Of Zns Nanomaterials, Suresh Pillai, Michael Seery, Damian Synnott, John Colreavy, Stephen Hinder Jan 2013

Novel Microwave Assisted Synthesis Of Zns Nanomaterials, Suresh Pillai, Michael Seery, Damian Synnott, John Colreavy, Stephen Hinder

Articles

A novel ambient pressure microwave-assisted technique is developed in which silver and indium modified ZnS is synthesised. The as prepared ZnS is characterised by X-ray diffraction, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and luminescence spectroscopy. This procedure produced crystalline materials with particle sizes below 10 nm. The synthesis technique leads to defects in the crystal which induce mid energy levels in the band gap and lead to indoor light photocatalytic activity. Increasing the amount of silver causes a phase transition from cubic blende to hexagonal phase ZnS. In a comparative study, when the ZnS cubic blende is heated in a conventional …


Utilising Caging Techniques To Investigate Metal Assimilation In Nucella Lapillus, Mytilus Edulis And Crassostrea Gigas At Three Irish Coastal Locations, Michelle Giltrap, Ailbhe Macken, Maria Davoren, Evin Mcgovern, Barry Foley, Martin Larsen, Jonathan White, Brendan Mchugh Jan 2013

Utilising Caging Techniques To Investigate Metal Assimilation In Nucella Lapillus, Mytilus Edulis And Crassostrea Gigas At Three Irish Coastal Locations, Michelle Giltrap, Ailbhe Macken, Maria Davoren, Evin Mcgovern, Barry Foley, Martin Larsen, Jonathan White, Brendan Mchugh

Articles

Pollution by metals has been of increasing concern for a number of decades but at present, the mechanism of metal accumulation in sentinel species is not fully understood and further studies are required for environmental risk assessment of metals in aquatic environments. The use of caging techniques has proven to be useful for assessment of water quality in coastal and estuarine environments. This study investigates the application of caging techniques for monitoring uptake of 20 elements in three marine species namely Nucella lapillus, Mytilus edulis and Crassostrea gigas. Stable isotopes were used to determine predatory effects and also used for …


A Highly Efficient Tio2-Xcx Nano-Heterojunction Photocatalyst For Visible-Light Induced Antibacterial Applications, Vinodkumar Etacheri, Michael Seery, Stephen Hinder, Georg Michlits, Suresh Pillai Jan 2013

A Highly Efficient Tio2-Xcx Nano-Heterojunction Photocatalyst For Visible-Light Induced Antibacterial Applications, Vinodkumar Etacheri, Michael Seery, Stephen Hinder, Georg Michlits, Suresh Pillai

Articles

Visible-light-induced antibacterial activity of carbon-doped anatase-brookite titania nano-heterojunction photocatalysts are reported for the first time. These heterostructures were prepared using a novel low temperature (100 °C) non-hydrothermal low power microwave (300 W) assisted method. Formation of interband C 2p states was found to be responsible for the band gap narrowing of the carbon doped heterojunctions. The most active photocatalyst obtained after 60 minutes of microwave irradiation exhibits a 2-fold higher visible-light induced photocatalytic activity in contrast to the standard commercial photocatalyst Evonik-Degussa P-25. Staphylococcus aureus inactivation rate constant for carbon-doped nano-heterojunctions and the standard photocatalyst was 0.0023 and -0.0081 min …


Uv And Visible Light Activated Tio2 Photocatalysis Of 6-Hydroxymethyluracil, A Model Compound For The Potent Cyanotoxin Cylindrospermopsin, Cen Zhao, Miquel Pelaez, Dionysios Dionysiou, Suresh Pillai, John Byrne, Kevin O'Shea Jan 2013

Uv And Visible Light Activated Tio2 Photocatalysis Of 6-Hydroxymethyluracil, A Model Compound For The Potent Cyanotoxin Cylindrospermopsin, Cen Zhao, Miquel Pelaez, Dionysios Dionysiou, Suresh Pillai, John Byrne, Kevin O'Shea

Articles

TiO2 photocatalyses of 6-hydroxymethyl uracil (6-HOMU) a model compound for the potent cyanotoxin, cylindrospermopsin (CYN), were carried out employing visible and UV irradiation using different non-metal doped TiO2 materials, nitrogen and fluorine-TiO2 (NF-TiO2), phosphorus and fluorine-TiO2 (PF-TiO2) and sulfur-TiO2 (S-TiO2). The model compound was readily degraded under UV TiO2 photocatalysis with pseudo-first-order rate constants (k) of 2.1, 1.0, and 0.44 h−1 for NF-TiO2, PF-TiO2 and S-TiO2, respectively. Under visible light activated (VLA), NF-TiO2 was the most active photocatalyst, PF-TiO …


Synthesis Of Orthogonally Protected Azalanthionines (Lanazanines) By Sequential Ring-Opening Of N-Substituted Aziridine 2-Carboxylates, Keith O'Brien, Keith Ó Proinsias, Fintan Kelleher Jan 2013

Synthesis Of Orthogonally Protected Azalanthionines (Lanazanines) By Sequential Ring-Opening Of N-Substituted Aziridine 2-Carboxylates, Keith O'Brien, Keith Ó Proinsias, Fintan Kelleher

Articles

Orthogonally protected azalanthionines (lanazanines, 4-azadiaminopimelic acids or b-aminoalaninoalanines) have been synthesised in good yields by the ring-opening of N-protected aziridine 2-carboxylates with suitably protected diaminopropanoic acids (DAPs). The required DAPs were also synthesised by ring-opening of N-protected aziridine 2-carboxylates with para-methoxybenzylamine.


The Bench Synthesis Of Silver Nanostructures Of Variable Size And An Introductory Analysis Of Their Optical Properties, Aoife Power, Tony Betts, John Cassidy Jan 2013

The Bench Synthesis Of Silver Nanostructures Of Variable Size And An Introductory Analysis Of Their Optical Properties, Aoife Power, Tony Betts, John Cassidy

Articles

A laboratory practical was designed for use by both undergraduate and second level students to demonstrate the synthesis and characterisation of tuneable silver colloids. It clearly illustrates the novel optical properties of silver nanoparticles compared to the bulk metal. The synthesis is both rapid and repeatable, and can be conducted on the laboratory bench at room temperature.


Sol-Gel Characteristics For Corrosion Resistance Of Anodised Aluminium, Michael Whelan, John Cassidy, Brendan Duffy Jan 2013

Sol-Gel Characteristics For Corrosion Resistance Of Anodised Aluminium, Michael Whelan, John Cassidy, Brendan Duffy

Articles

Conventional anodising electrolytes based on sulphuric acid, oxalic acid and phosphoric acid have been used to form nanoporous layers on AA3003-H14 and sealed with silane based sol-gel sealers. It is shown that the sol-gel chemistries have varying levels of pore penetration depending on the synthesis conditions. The extent of sol-gel penetration and pore sealing is analysed by electron microscopy and energy dispersive x-ray spectroscopy. To describe the sealing phenomena observed a sol-gel penetration and sealing rating has been proposed to explain the interactions of the sol-gels with the pores of the anodised layers. The corrosion resistance of the sol-gel sealed …


Synthesis And Modification Of Octafluoro[2.2]Paracyclophane (Parylene Af4), Craig Hicks, Brendan Duffy, Gráinne Hargaden Jan 2013

Synthesis And Modification Of Octafluoro[2.2]Paracyclophane (Parylene Af4), Craig Hicks, Brendan Duffy, Gráinne Hargaden

Articles

Parylenes are a class of organic compounds which have gained significant attention due to their application as coatings in areas such as medical devices and electronics. This review highlights the development of synthetic pathways to Octafluoro[2.2]Paracyclophane, commonly referred to as parylene AF4. Methods which have been used to functionalise AF4 are also presented.