Raman Spectroscopic Analysis of Geological and Biogeological Specimens of Relevance to the ExoMars Mission

H.G.M.E., I.H., and R.I. acknowledge the support of the STFC Research Council in the UK ExoMars programme. J.J. and P.V. acknowledge the support of the Grant Agency of the Czech Republic (210/10/0467) and of the Ministry of Education of the Czech Republic (MSM0021620855).Peer reviewedPublisher PD

Wind tunnel and numerical study of a small vertical axis wind turbine

This paper presents a combined experimental and computational study into the aerodynamics and performance of a small scale vertical axis wind turbine (VAWT). Wind tunnel tests were carried out to ascertain overall performance of the turbine and two- and three-dimensional unsteady computational fluid dynamics (CFD) models were generated to help understand the aerodynamics of this performance. Wind tunnel performance results are presented for cases of different wind velocity, tip-speed ratio and solidity as well as rotor blade surface finish. It is shown experimentally that the surface toughness on the turbine rotor blades has a significant effect on performance. Below a critical wind speed (Reynolds number of 30,000) the performance of the turbine is degraded by a smooth rotor surface finish but above the turbine performance is enhanced by a smooth surface finish. Both two bladed and three bladed it, rotors were tested and a significant increase in performance coefficient is observed for the higher solidity rotors (three bladed rotors) over most of the operating range. Dynamic stalling behaviour and the resulting large and rapid changes in force coefficients and the rotor torque are shown to be the likely cause of changes to rotor pitch angle that occurred during early testing. This small change in pitch angle caused significant decreases in performance. The performance coefficient predicted by the two dimensional computational model is significantly higher than that of the experimental and the three-dimensional CFD model. The predictions show that the presence of the over tip vortices in the 3D simulations is responsible for producing the large difference in efficiency compared to the 2D predictions. The dynamic behaviour of the over tip vortex as a rotor blade rotates through each revolution is also explored in the paper. (C) 2009 Elsevier Ltd. All rights reserved

Microorganism response to stressed terrestrial environments: a raman spectroscopic perspective of extremophilic life strategies

Raman spectroscopy is a valuable analytical technique for the identification of biomolecules and minerals in natural samples, which involves little or minimal sample manipulation. In this paper, we evaluate the advantages and disadvantages of this technique applied to the study of extremophiles. Furthermore, we provide a review of the results published, up to the present point in time, of the bio- and geo-strategies adopted by different types of extremophile colonies of microorganisms. We also show the characteristic Raman signatures for the identification of pigments and minerals, which appear in those complex sample

INFO 2009 Coursework 2 - Go Green - Group 7 - Green ICT

A Website on GREEN ICT by the Go Green Group as a part of the resource set made for the Info2009 2011-12 coursewor

Analysis of Trace and Essential Elements, Phenolic and Flavonoid Compounds in Libyan Honey Samples Collected from Misurata Markets

Honey is a popular natural food product with a very complex composition comprising both organic and inorganic constituents. The composition of particular honey is strongly influenced by both natural and anthropogenic factors, which vary based on its botanical and geographical origins. It is observed that although the honey which are produced in Libya are of a good quality, it does contain heavy metals. The contents of the metals found in Libyan honey samples were found to be between 465.1-792 mg/kg for Na, 1100.8-1781.6 mg/kg for K, 927.79-1186.6 mg/km for Ca, 0.0033- 0.0177 mg/kg for Cd, 0.0029- 0.0241mg/kg for Pb, 0.0012- 0.0042mg/kg for Cr, 0.004-0.032 mg/kg for Cu, 0.72-1.37 mg/kg for Ni and 3.677-7.430 mg/kg for Zn. These results indicated that the quality of the Libyan honey samples tested was very good and matched the world standard properties of honey. Also, the Libyan honey samples examined have a high level of phenolic (792- 99 mg/kg ) and flavonoid (1012-687mg/kg) compounds compared with other hone

Monitoring of Heavy Metal Content in Tawargah Pond in Libya

YesThe current study investigated the distribution of inorganic metals in the biggest reservoir in the neighbourhood of Misurata City, Tawargah Pond. The investigation was carried out during the topical periods of dry and wet season between August 2010 and January 2011. Levels of trace metals lead (Pb), copper (Cu), iron (Fe) and zinc (Zn)) were determined in the water samples taken. An atomic absorption spectrophotometer, Model 180-30 Hitachi, was used to determine heavy metal concentrations. The instrument was calibrated and standardized with different working standards. After making sure that the instrument was properly calibrated and results of the standard measurements were in the confidence limit, the concentration of metals in each sample was measured individually. High levels of lead and iron were found in water which indicates a possible contribution from the industrial activities and air pollution

Understanding the application of Raman spectroscopy to the detection of traces of life

This is the publisher's version, also available electronically from "http://online.liebertpub.com".Investigating carbonaceous microstructures and material in Earth's oldest sedimentary rocks is an essential part of tracing the origins of life on our planet; furthermore, it is important for developing techniques to search for traces of life on other planets, for example, Mars. NASA and ESA are considering the adoption of miniaturized Raman spectrometers for inclusion in suites of analytical instrumentation to be placed on robotic landers on Mars in the near future to search for fossil or extant biomolecules. Recently, Raman spectroscopy has been used to infer a biological origin of putative carbonaceous microfossils in Early Archean rocks. However, it has been demonstrated that the spectral signature obtained from kerogen (of known biological origin) is similar to spectra obtained from many poorly ordered carbonaceous materials that arise through abiotic processes. Yet there is still confusion in the literature as to whether the Raman spectroscopy of carbonaceous materials can indeed delineate a signature of ancient life. Despite the similar nature in spectra, rigorous structural interrogation between the thermal alteration products of biological and nonbiological organic materials has not been undertaken. Therefore, we propose a new way forward by investigating the second derivative, deconvolution, and chemometrics of the carbon first-order spectra to build a database of structural parameters that may yield distinguishable characteristics between biogenic and abiogenic carbonaceous material. To place Raman spectroscopy as a technique to delineate a biological origin for samples in context, we will discuss what is currently accepted as a spectral signature for life; review Raman spectroscopy of carbonaceous material; and provide a historical overview of Raman spectroscopy applied to Archean carbonaceous materials, interpretations of the origin of the ancient carbonaceous material, and a future way forward for Raman spectroscopy

Microwave Power Transmission System Studies. Volume 1: Executive Summary

A study of microwave power generation, transmission, reception and control was conducted as a part of a program to demonstrate the feasibility of power transmission from geosynchronous orbit. A summary is presented of results concerning design approaches, estimated costs (ROM), critical technology, associated ground and orbital test programs with emphasis on dc to rf conversion, transmitting antenna, phase control, mechanical systems, flight operations, ground power receiving-rectifying antenna with systems analysis, and evaluation. Recommendations for early further in-depth studies complementing the technology program are included

Microwave power transmission system studies. Volume 2: Introduction, organization, environmental and spaceborne systems analyses

Introduction, organization, analyses, conclusions, and recommendations for each of the spaceborne subsystems are presented. Environmental effects - propagation analyses are presented with appendices covering radio wave diffraction by random ionospheric irregularities, self-focusing plasma instabilities and ohmic heating of the D-region. Analyses of dc to rf conversion subsystems and system considerations for both the amplitron and the klystron are included with appendices for the klystron covering cavity circuit calculations, output power of the solenoid-focused klystron, thermal control system, and confined flow focusing of a relativistic beam. The photovoltaic power source characteristics are discussed as they apply to interfacing with the power distribution flow paths, magnetic field interaction, dc to rf converter protection, power distribution including estimates for the power budget, weights, and costs. Analyses for the transmitting antenna consider the aperture illumination and size, with associated efficiencies and ground power distributions. Analyses of subarray types and dimensions, attitude error, flatness, phase error, subarray layout, frequency tolerance, attenuation, waveguide dimensional tolerances, mechanical including thermal considerations are included. Implications associated with transportation, assembly and packaging, attitude control and alignment are discussed. The phase front control subsystem, including both ground based pilot signal driven adaptive and ground command approaches with their associated phase errors, are analyzed

Raman spectroscopic analysis of an early 20th century English painted organ case by Temple Moore

An organ case from Lincoln, England, designed by the architect Temple Moore in 1907 was examined during conservation work using Raman spectroscopy in order to analyze the decorative paint composition. Samples from the six principal colours were extracted and examined using a Bruker Senterra R200-L spectrometer. The results are the first known formal analysis of a painted scheme by this architect, and they reveal a mixture of commonly used pigments for the period and the unexpected use of simpler, earth pigments, along with an unusual admixture in the red, along with an organic additive. The findings are of importance to both the conservation of Temple Moore’s artwork, in understanding the experimentation used in early twentieth-century England, and in furthering our knowledge of ecclesiastical decorative artwork of the late nineteenth and early twentieth centuries