Intelligent pigments and plastics for CO2 detection

A novel CO2 intelligent pigment is incorporated into a thermoplastic polymer to create a long-lived CO2-sensitive plastic film which is characterised and then compared to a traditional solvent-based CO2 indicator film

Detoxification of water by semiconductor photocatalysis

An overview of the use of semiconductor photocatalysis for water purification is given. The basic principles of semiconductor photocatalysis are described along with the current understanding of the underlying reaction mechanism(s) and how it fits in with the major features of the observed Langmuir-Hinshelwood-type kinetics of pollutant destruction. These features are illustrated based on literature on the destruction of aqueous solutions of 4-chlorophenol as a pollutant, using titanium dioxide as the photocatalyst. The range of organic and inorganic pollutants that can be destroyed by semiconductor photocatalysis are reported and discussed. The basic considerations that need to be made when designing a reactor for semiconductor photocatalysis are considered. These include: the nature of the reactor glass, the type of illumination source, and the nature and type of semiconductor photocatalyst. The key basic photoreactor designs are reported and discussed, including external illumination, annular, and circular photoreactors. Actual designs that have been used for fixed and thin falling film semiconductor photocatalyst reactors are illustrated and their different features discussed. Basic non-concentrating and concentrating solar photoreactors for semiconductor photocatalysis are also reported. The design features of the major commercial photocatalytic reactor systems for water purification are reported and illustrated. Several case studies involving commercial photocatalytic reactors for water purification are reported. An attempt is made briefly to compare the efficacy of semiconductor photocatalysis for water purification with that of other, more popular and prevalent water purification processes. The future of semiconductor photocatalysis as a method of purifying water is considered

A concise summary of the International System of Units, the SI

The Bureau International des Poids et Mesures, the BIPM, was established by Article 1 of the Convention du Mètre, on 20 May 1875, and is charged with providing the basis for a single, coherent system of measurements to be used throughout the world. The decimal metric system, dating from the time of the French Revolution, was based on the metre and the kilogram. Under the terms of the 1875 Convention, new international prototypes of the metre and kilogram were made and formally adopted by the first Conférence Générale des Poids et Mesures (CGPM) in 1889. Over time this system developed, so that it now includes seven base units. In 1960 it was decided at the 11th CGPM that it should be called the Système International d’Unités, the SI (in English: the International System of Units). The SI is not static but evolves to match the world’s increasingly demanding requirements for measurements at all levels of precision and in all areas of science, technology, and human endeavour. This document is a summary of the SI Brochure, a publication of the BIPM which is a statement of the current status of the SI. The seven base units of the SI, listed in Table 1, provide the reference used to define all the measurement units of the International System. As science advances, and methods of measurement are refined, their definitions have to be revised. The more accurate the measurements, the greater the care required in the realization of the units of measurement

Kinetics of liquid phase semiconductor photoassisted reactions : supporting observations for a pseudo-steady-state model

The kinetics of liquid phase semiconductor photocatalytic and photoassisted reactions are an area of some debate, reignited recently by an article by Ollis1 in which he proposed a simple pseudo-steady-state model to interpret the Langmuir-Hinshelwood type kinetics, commonly observed in such systems. In the current article, support for this model, over other models, is provided by a reinterpretation of the results of a study, reported initially in 1999,2 of the photoassisted mineralization of 4-chlorophenol, 4-CP, by titania films and dispersions as a function of incident light intensity, I. On the basis of this model, these results indicate that 4-CP is adsorbed more strongly on P25 TiO2 when it is in a dispersed, rather than a film form, due to a higher rate constant for adsorption, k1. In addition, the kinetics of 4-CP removal appear to depend on Iâ, where â ) 1 or 0.6 for when the TiO2 is in a film or a dispersed form, respectively. These findings are discussed both in terms of the pseudo-steady-state model and other popular kinetic models

Resin transfer moulding: Novel fabrics and tow placement techniques in highly loaded carbon fibre composite aircraft spars

A BAE Systems /UK EPSRC funded project Flaviir, is investigating the design and manufacture of low cost carbon fibre composite airframe structures. Novel binder coated unidirectional fibre tapes and tows were developed to enable the design of optimised primary structures. The RTM technique was applied to mould net shape sections of spar components. Various designs of wing attachment lugs were manufactured with a range of reinforcement materials, including non crimp fabric, novel binder coated tapes and conventional unidirectional prepreg. Alongside these, a novel technique termed optimised tow lay up (OTL) was used to reduce the weight. Binder coated carbon fibre tow is placed around the structure in the principal stress directions to increase both bearing strength and overall component stiffness. The novel materials, manufacturing technique and initial element test results are presented

Impacts of elevated atmospheric ozone on peatland below-ground DOC characteristics

Rising concentrations of tropospheric ozone are having detrimental impacts on the growth of crop and forest species and some studies have reported inhibition of the allocation of carbon below ground. The effects of ozone on peatland ecosystems have received relatively little attention, despite their importance within the global carbon cycle. During this study, cores from a Welsh minerotrophic fen and ombrotrophic bog were exposed to four ambient/ elevated ozone concentration regimes representing current and predicted 2050 profiles. A large and significant reduction in the concentration of porewater dissolved organic carbon (DOC) was recorded in the fen cores exposed to the elevated ozone concentrations (up to −55%), with a concurrent shift to a higher molecularweight of the remaining soil carbon. No effects of ozone on DOC concentrations or characteristics were recorded for the bog cores. The data suggest higher ozone sensitivity of plants growing in the fen-type peatland, that the impacts on the vegetation may affect soil carbon characteristics through a reduction in root exudates and that theremay have been a shift in the source of substrate DOC for microbial consumption from vegetation exudates to native soil carbon. Theremay also have been a direct effect of ozone molecules reacting with soil organic matter after being transported into the soil through the aerenchyma tissue of the overlying vegetation. These qualitative changes in the soil carbon in response to elevated ozone may have important implications for carbon cycling in peatland ecosystems, and therefore climate change

MiniBooNE: Status of the Booster Neutrino Experiment

MiniBooNE is preparing to search for nu_mu to nu_e oscillations at Fermilab. The experiment is designed to make a conclusive statement about LSND's neutrino oscillation evidence. We give a status report on the preparation of the experiment and outline the experimental prospects.Comment: 6 pages, To appear in Proceedings of the XIX International Conference on Neutrino Physics and Astrophysics (Neutrino 2000), Sudbury. Canada, 16-21 June 200

Substance Abuse Therapeutics

This chapter provides a broad overview of therapies for substance abuse. These therapies are understood in the context of the history of drug use in the United States and factors that influenced the expansion and regulation of substance use. This is followed by a discussion of how the complexity of these factors was associated with difficulties in understanding substance misuse and created challenges to the creation of effective treatment systems. The chapter reviews the moral and disease models of addiction before discussing the diagnosis of substance-related disorders. The chapter describes major treatment approaches and their efficacy

Genetic analysis of strain differences in pre-laying behaviour in the fowl: an ethological and genetic analysis of differences in the pre-laying behaviour of two strains of domestic fowl (Gallus gallus domesticus) confined in battery cages: a study pertaining to the evolution and adaptiveness of behaviour under conditions of natural and artificial selection

This thesis deals with the description and analysis of the pre-laying behaviour of two strains of domestic fowl (Gallus gallus domestlcus) in battery cages. Hens from one of these strains, known as the S line, showed stereotyped pacing behaviour before laying. Hens from the other strain, known as the T line, showed little or no pacing behaviour and tended to sit.Selection over two generations, for pacing in the S line and for sitting in the T line, consistently increased both variables: indicating genetic variation in the expression of the two traits.Crosses between the two lines, extending to backcross and Fl generations, indicated that the tendencies to pace and to sit during the pre-laying period were inherited separately. The tendency to sit appeared to be inherited additively, whereas the tendency topace (as opposed to not pacing) appeared to be inherited in adichotomous fashion, controlled by a single gene or a polygenic threshold system. Neither trait was sex-linked.It is suggested that the differences in the pre-laying behaviour of the two strains are due to differences in responsiveness to releasers for sitting behaviour. The T line generalise to sub-obtimal stimuli from the cage associated with the release of sitting behaviour; whilst the S line fail to do so,become frustrated, and in response to this frustration exhibit stereotyped pacing behaviour.The differences in the pre-laying behaviour of the two strains did not appear to be related to their responses to aversive stimuli or the frustration of feeding behaviour, or to their ability togeneralise to sub-optimal stimuli other than those associated with the release of sitting during the period before laying.Theoretical aspects of the study relelated to the genetics of behaviour and its evolution are relevant to Tinbergen's "derived" activities hypothesis, which postulates that some visual displays have been derived from the behaviour shown in response to motivational conflict or thwarting.Practical aspects of the study relate to the improvement of the welfare of domestic animals kept under intensive husbandry conditions by breeding domestic animals better adapted to life under such conditions than present day livestock