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Trace fossils from the Middle Devonian Caherbla Group of the Dingle Peninsula, southwest Ireland, record a diverse arthropod fauna inhabiting a hot-arid intracontinental rift setting. Aeolian dunefield and coeval fluvial interdune deposits interfinger spatially and temporally with alluvial fan sedimentary rocks. Three distinct trace fossil assemblages are recognized. The Taenidium-Scoyenia ichnocoenosis occurs in alluvial fan and fluvial channel deposits, and includes the large backfilled burrow Taenidium, interpreted as eoarthropleurid aestivation chambers. The Rusophycus-Protichnites ichnocoenosis, composed of arthropod trackways and surface pits, occurs in an interdune ponded area that was susceptible to ephemeral fluvial flow, with Rusophycus showing preferred orientation into the oncoming palaeocurrent. Both the Taenidium-Scoyenia and Rusophycus-Protichnites ichnocoenoses are assignable to the globally recurring continental Scoyenia ichnofacies. They are clearly substrate-controlled and moisture-related due to the ephemeral nature of the fluvial system. The Palmichnium-Entradichnus ichnocoenosis occurs in aeolian dune deposits, and includes Palmichnium, attributed to large stylonurid eurypterids, and Diplichnites, attributed to eoarthropleurids. These trackways represent the activities of dune pioneers that left their fluvial habitat to forage for detritus. Interface burrows (Entradichnus, Palaeophycus) were also constructed by arthropods moving just under the sand surface and vertical burrows (Cylindricum, Pustulichnus) were made by arthropods digging downward. Trace preservation in the aeolian environment was probably enhanced by heavy nocturnal dew-fall or light rain. The Palmichnium-Entradichnus ichnocoenosis is assigned to the globally recurring aeolian Octopodichnus-Entradichnus ichnofacies. This aeolian facies, and associated ichnofauna described herein, represents the oldest development of a unique erg system in the Old Red Sandstone (Devonian) of the southern British Isles, and one of the oldest and most diverse aeolian ichnofaunas to be reported worldwide. Copyright © 2011 John Wiley & Sons, Ltd.

Triassic dryland fluvial systems occur infilling extensional and post-rift basins across northwest Europe. These systems were deposited by streams draining off the major basin margin catchments of Greenland, Fennoscandia, the Scottish Highlands and the remnant Variscan mountains. Fluvial drainage was dominantly endorheic in character, and terminated in playa, aeolian dune, sabkha or marsh settings. Whilst the ambient basin climate fluctuated through varying levels of aridity and humidity, the dispersal of sand into these basins was critically dependant on catchment run-off from the major, basin flanking regions. In the Early Triassic the Tethyan monsoon drove seasonal precipitation over the Variscan mountains which transported sediment northward into arid dune fields and playa. In addition, far-travelled fluvial systems supplied sediment from distant, wetter catchments. Through the Middle and Late Triassic the effects of the Tethyan monsoon apparently weakened, and sand-prone fluvial systems draining off the Variscan mountains were more limited in areal extent, but expanded during pluvial episodes. However, Greenland and Fennoscandia maintained sediment supply from the north, with perennial run-off from Fennoscandia able to maintain marshes and levels of vegetation cover not encountered elsewhere in the region and to episodically drive major exorheic drainage systems into the Tethys Sea. Published climatic simulations are consistent with these observations, which indicate that Greenland, and particularly Fennoscandia, had precipitation levels higher than the regions to the south with a positive precipitation: evaporation balance. Copyright © 2009 John Wiley & Sons, Ltd.

The lower part of the Old Red Sandstone in the Dingle Penisula has been previously assigned to one lithostratigraphic group (Dingle Group) despite marked variations in sedimentary facies. However the apparently oldest non-marine sequence in the northwest of the peninsula has sedimentary and lithological attributes that contrast strongly with those of the late Silurian-early Devonian Dingle Group to the south. This northern sequence, here renamed the Smerwick Group, evolved independently of the Dingle Group in a separate basin of deposition. Field relationships between the two groups in the north of the peninsula are interpreted as indicating that the Smerwick Group overlies, with angular unconformity, a normal Dingle Group succession. Similarly, it is argued that the Smerwick Group overlies, with angular unconformity, the Dingle Group in the northwest of the peninsula, but there the Dingle Group is attenuated, represented only by a conglomerate unit some 10 m thick. In the absence of biostratigraphic evidence the age of the Smerwick Group is poorly constrained. Nevertheless, we propose a tectonic model that suggests that the Smerwick Group evolved within a small extensional half-graben on the northern margin of the Munster Basin. This model accounts for the stratigraphic and structural relationships observed, and implies that the Smerwick Group is of Late Devonian age.

Trace fossils of Beaconites type are found abundantly and widely in the Old Red Sandstone magnafacies of the British Isles, particularly in fluviatile deposits, where they occur in or closely associated with channel sandstones. Because of their giant size, however, terminations to the sediment-filled burrows are almost impossible to detect, and it has hitherto been uncertain whether the Beaconites organism dwelt in or near active rivers, or merely colonized the sandy deposits at their abandoned sites. At Llanstephan in southwest Wales B. antarcticus is preserved in a laterally accreted sandstone, a unique example of the trace fossil being truncated by an erosion surface cut during the sideways growth of a presumed point bar. The Beaconites organism is therefore thought to have lived in and near active river channels, where a moist environment was provided.

The Devonian Old Red Sandstone Ridgeway Conglomerate Formation crops out in Pembrokeshire, SW Wales. It was deposited as part of a dryland alluvial fan, axial fluvial valley deposystem. It conformably overlies the mid Lochkovian Freshwater West Formation and probably predates deposition of the Lower Cosheston Group Mill Bay Formation indicating an Early Devonian (latest Lochkovian to earliest Pragian) age, rather than a Middle Devonian age as suggested by previous workers. It therefore represents the youngest preserved formation of the Milford Haven Group south of the Ritec Fault. The Formation thickens drastically into the Ritec Fault, indicating its control on sedimentation. The half-graben topography initiated deposition of a hangingwall alluvial fan that was sourced from a southerly Lower Palaeozoic/Precambrian provenance within the present-day Bristol Channel. The Formation is heterolithic in nature, with deposits on the fan reflecting a mixture of processes. Conglomerates were deposited primarily by laterally extensive sheetfloods, and as bars in low-relief, laterally accreted channels. Sandstones were also predominantly deposited by sheetfloods. Gritty mudrocks in comparison demonstrate deposition by cohesive debris flows. The fan prograded northward and interfingered with a low-gradient, high-sinuosity fluvial channel system dominated by inclined and non-inclined heterolithic stratification. Thinly laminated mudstone and sandstone interbeds were deposited in ephemeral fan-toe and axial valley lakes that may have developed during sub-humid climatic episodes. The lacustrine heterolithic association has associated matgrounds and possible ‘algal roll-up’ structures. Calcretized peetee structures and root traces comprise a lake margin calcrete association. Fan gravels prograded into the axial fluvial valley during periods of increased sediment flux that may represent semi-arid conditions and/or episodes of tectonic activity. Calcretes of varying development were established in both the fan and axial valley zones. Calcretes with lower stages of development are more proximal to the Ritec Fault reflecting decreased soil residence times and high deposition rates within the axial valley. More strongly developed soil profiles on the fan may indicate sequence boundaries associated with low sediment flux, or increased soil residence time due to active fan-channel migration (the pedofacies concept). Groundwater calcretes have sharp-based and layer-bound calcrete profiles. Gully-bed cements are locally developed within the fan gravels. Copyright © 2007 John Wiley & Sons, Ltd.

Public awareness and concern over food safety, together with intensified regulatory control over the impact of food processing operations on the environment, present new challenges to the industry. This paper outlines a systematic approach to water management that addresses both cost-reduction strategies and environmental performance improvement, which can enhance industry image while maintaining product and brand integrity. Many companies already operate a well-defined environmental management system (EMS), and some have already sought accreditation to ISO 14001. However, the implementation of, among others, the Integrated Pollution Prevention and Control (IPPC) Directive, the Water Directive and the Climate Change Levy (CCL) are raising new and important questions.

The Lower Devonian (Lochkovian-Emsian) Cosheston Group of south Pembrokeshire is one of the most enigmatic units of the Old Red Sandstone of Wales. It consists of a predominantly green, exceptionally thick succession (up to 1.8 km) within the red c. 3 km-thick fill of the Anglo-Welsh Basin, but occupies a very small area (27 km2). Four formations—Llanstadwell (LLF), Mill Bay (MBF), Lawrenny Cliff (LCF) and New Shipping (NSF)—group into lower (LLF + MBF) and upper (LCF + NSF) units on stratigraphical and sedimentological criteria. Two palynostratigraphic associations (Hobbs Point and Burton Cliff) are recognised in the LLF. Overall, the Cosheston succession comprises a fluvial, coarsening-upward megasequence, mostly arranged in fining-upward rhythms. It is interpreted as the fill of an east-west graben bounded by faults to the north and south of the Benton and Ritec faults, respectively. Both ‘lower Cosheston’ formations were deposited by east-flowing, axial river systems draining a southern Irish Sea landmass. Drainage reversal, early in the deposition of the LCF, resulted in ‘upper Cosheston’ lateral, SW-flowing rivers which carried predominantly second- and multi-cycle detritus. The ‘lower Cosheston’ is characterized by an abundance of soft-sediment deformation structures, probably seismically triggered by movements along the graben's northern bounding fault. A minimum average (≥ mesoseismic) earthquake recurrence interval of c. 4000 yr is estimated for the MBF. This and the correlative Senni Formation of south-central Wales form a regionally extensive green-bed development that represents a pluvial climatic interval. Copyright © 2006 John Wiley & Sons, Ltd.

Both regional and localized tectonic events controlled deposition within the Wenlock and early Ludlow of SW Wales. Estuarine deposits within north–south-tending incised valleys dominate the youngest (Homerian) Gray Sandstone Group, valley incision being probably related to changing base-levels associated with Avalonia/Laurentian collision. Available accommodation space was outpaced by sediment supply, with the Red Cliff Formation (Late Ludfordian) defining a conformable transition from marine to Old Red Sandstone (ORS) deposition within the Marloes Peninsula. Sedimentation was dominated by fine-grained pedified siliciclastics, with subordinate fine-grained ephemeral sheet-flood sandstones. Local palaeocurrents indicate sediment transport from the south and west, though long-distance transport from a distant Laurentian provenance is assumed. A probable tectonically generated sequence boundary marks the base of petrographically distinctive, multi-storey pebbly sandstones of the Albion Sands Formation, deposited within the hangingwall valley of the active east–west-trending Wenall Fault. Sediment accommodation space was controlled by proximity to the tip-point of this important growth fault within the Lower ORS. Debris-flow-dominated fans, shed from both the hangingwall and footwall of the Wenall Fault, deposited the Lindsway Bay Formation, an exotic-clast conglomerate unit sourced predominantly from the south and west. It is uncertain as to whether movement along the Wenall Fault was caused by collision-related transtension, or rifting associated with the southern margin of Avalonia. Copyright © 2004 John Wiley & Sons, Ltd.

Sandstone bodies within the Lower Old Red Sandstone (ORS) in southern Pembrokeshire exhibit variability in architecture, sediment grade and composition both spatially and temporally. Four architectural styles are observed, namely decimetre- to metre-thick sheets, metre-thick multi-storey amalgamations, inclined-heterolithic units and ribbon geometries. Sandstone bodies in the Freshwater East Formation are sheet-like, heterolithic units several metres thick. An association with lingulids and wave ripples alludes to a marine influence, possibly estuarine tidal flats or storm washovers. Within the Moor Cliffs Formation, the most common sandstone bodies are centimetre- to metre-thick sheets with high width-to-depth ratios. Fine-grained sandstones represent sheet-flood deposition on unconfined, planar surfaces, whereas coarser-grained sandstones constitute distinctive amalgamations of discrete flood events, reflecting either a change in provenance or tectonic influence. Clear incision of coarse-grained, multi-storey units within the Inter-Tuff Moor Cliffs Formation reflects a change in relative sea-level, possibly tectonically induced. The base of the Conigar Pit Sandstone Member (CPSM) is marked by a distinctive, exotic-clast conglomerate defining the base to heterolithic, lateral-accretion bedsets and sandstone sheets. This association defines a significant influx of coarse-grained sediment post-Chapel Point Calcrete formation, an interval of presumed topographic stability across the Anglo-Welsh Basin. This influx must reflect rejuvenation of source regions, with changes in base-level reflecting either eustatic or tectonic influences. Commonly observed in the CPSM are fine-grained, inclined-heterolithic bedsets recording deposition by highly sinuous rivers with flashy discharge. Up-sequence within the CPSM are metre-thick, multi-storey amalgamations of predominatly trough cross-stratified medium- to coarse-grained sandstone. It is likely that these units are genetically related to contemporaneous decimetre-thick sandstone sheets, the latter being ‘splay’ events marginal to the main channel axis. The interbedding of multi-storey sandstones and fine-grained laterally accreted units reflects changes in provenance, slope and/or climate. Thickness variations within the Lower ORS detail significant thickening of all units northward into the Benton Fault. It seems likely that this thickening reflects variable accommodation space development associated with active growth along this and other WNW–ESE-trending faults, and migration of channel belts toward the footwall. Copyright © 2004 John Wiley & Sons, Ltd.

Within the UK, a large number of surveys are being carried out for the identification of asbestos in building materials. Pre-demolition or major refurbishment and building sampling surveys require that representative samples be analysed for asbestos. The primary technique for the analysis of asbestos fibres in bulk materials is polarized light microscopy (PLM). Since this method is based on visual estimation, it depends on the competence and experience of the analyst. Furthermore, PLM, in common with the other analytical methods used for the identification of asbestos in bulk materials, is a laboratory-based technique requiring samples to be collected and then sent to a laboratory for analysis. Raman spectroscopy is a powerful tool for mineral characterization and provides a molecular fingerprint for material. In recent years, new developments in optics and electronics have permitted the development of compact Raman spectrometers allowing in situ measurements. We report the performance of a robust, laboratory-based fibre-optic probe for the identification of asbestos in bulk materials by Raman spectroscopy. Thirty-eight samples were analysed, and the results showed that 95% of the samples were successfully identified as either asbestos free or containing one or more asbestos components. A success rate of 100% was found for asbestos insulating board and asbestos cement materials. The results indicated that a Raman probe device for detecting asbestos does have potential, but a number of issues need to be addressed before an on-site system can be developed. Copyright © 2004 John Wiley & Sons, Ltd.

Raman scattering properties from various GaN thin films grown on sapphire by metalorganic chemical vapor deposition were studied. Visible micro-Raman measurements show different mode behaviors with different laser incidence configurations. Raman lineshape analyses through two sets of equations led to the monitoring of the sample quality and stress and the optical determination of electrical properties of GaN films. An approximate 3 cm−1 shift in the E1(LO) mode wavenumber is observed across the GaN film from the sapphire/GaN interface to the GaN surface, indicating the spatial variation of strains along the film growth direction within a few microns thickness range. Combined Raman and PL spectra were obtained under UV excitation, and interesting high-order resonance Raman features were observed using a sensitive UV–Raman–photoluminescence microscope. A new way to characterize p-type GaN is introduced. Copyright © 2001 John Wiley & Sons, Ltd.

Raman microscopy was used to identify unambiguously the anions of lead and barium in gunshot residues (ca. 5 μm in size) deposited on cellulosic substrates. It was found that most of the particles consist of mixtures of oxides, sulphate and carbonate (along with carbon). In particular, there is strong evidence for the formation of mixed oxides of iron but only relatively little evidence for oxides of antimony. The Raman technique has been shown to be able to identify individual or mixed components and to confirm the presence of microcrystalline particles with a particular crystal structure (e.g. orthorhombic lead oxide). © 1998 John Wiley & Sons, Ltd.

The antimicrobial enrofloxacin was tested for its ability to control atypical Aeromonas salmonicida in Atlantic tomcod (Microgadus tomcod). An initial experiment showed that a single injection of enrofloxacin, at a dosage of approximately 5 mg active ingredient per kilogram of fish, prevented the formation of characteristic furunculosis lesions but did not significantly reduce mortality during a 76-d period. In a second experiment, in which we administered the antimicrobial at days 1, 10, and 45, treated fish experienced significantly lower mortality than did the control fish. Three of 10 necropsied fish treated with enrofloxacin produced positive cultures of atypical A. salmonicida, whereas the pathogen was successfully cultured from 7 of 10 control fish. Cultures were obtained from skin lesions or from infected areas of buccal or caudal regions. Sixteen of 50 (32%) fish from the enrofloxacin treatment died during the experiment, and 30% of the dead fish displayed circular lesions on the trunk. ...

The galactosylation status of IgG from both control and arthritic DBA-1 mice was determined by exoglycosidase sequencing and an anti-GlcNAc monoclonal based ELISA. Two to three weeks after arthritis onset mice with collagen-induced arthritis (CIA) showed a modest increase in IgG anti-GlcNAc reactivity against controls (0.644 +/- 0.080 and 0.530 +/- 0.087, respectively, mean absorbance +/- SEM n = 4) consistent with previous literature reports. However, the authors were unable to detect any significant changes in the galactosylation of purified IgG from arthritic and control mice using direct sequencing techniques (percentage G0 of 34.5% +/- 1.9 and 37.7% +/- 2.4, respectively, mean +/- SEM n = 4). It has been demonstrated that a correlation exists between percentage G0 and anti-GlcNAc reactivity for purified human IgG and sera samples, respectively; no such correlation was found for murine IgG and sera. The galactosylation of purified polyclonal murine IgG isotypes was analysed on a separate group of arthritic mice selected for their high anti-GlcNAc reactivities. No significant differences were observed between control and arthritic mice. Immunoglobulin G isotype specific differences were found, with IgG1 exhibiting the highest percentage G0 (45-48%) followed by IgG2a (27-37%), IgG3 (20-32%) and IgG2b the lowest (13-17%). The percentage G0 and anti-GlcNAc reactivity of purified IgG1 and IgG2b showed a narrow range of values when compared to those of IgG2a and IgG3 samples. Pooled sera from both arthritic and control mice was used to purify large quantities of IgG3. Which on analysis revealed a fourfold increase in anti-GlcNAc reactivity in the arthritic sample compared to control. Paradoxically these same IgG3 samples contained similar percentage G0 levels as determined by direct sequencing. The results suggest that IgG1 and IgG2b exhibit isotype selective oligosaccharide processing as little sample heterogeneity could be observed. These two purified IgG isotypes displayed a good correlation between percentage G0 and anti-GlcNAc reactivity; this was in contrast to IgG2a and IgG3. Immunoglobulin G3 from arthritic mice may have G0 oligosaccharides selectively paired together with no net increase in percentage G0. This observation is discussed in detail as is the role of agalactosyl IgG in murine type II collagen-induced arthritis.

Two typical representatives of the Ediacaran biota, Ediacaria booleyi n.sp. and Nimbia occlusa have been found in deep-water turbidites within the Upper Cambrian Booley Bay Formation at Booley Bay in Co. Wexford, Eire. The examples of E. booleyi were transported over short distances by the turbidity currents and then impacted, in some instances at high angles, into the ocean floor muds where they formed moulds but, as their bodies decayed, these were filled by casting sand from the overlying turbidite. They preserved fine detail during transportation and impaction, thereby indicating the existence of a rigid body wall. The three-dimensional nature of their preservation allows reconstruction, which shows that Ediacaria had a discoid form with prominent relief, particularly on its dorsal side, which was divided into three main concentric zones with thin radial features, more evident at the periphery. The ventral side had lower relief, with alternate areas of coarse and fine concentric markings and numerous fine radial lines, some also thicker at the periphery. Nimbia occlusa are disc-like bodies of low relief and occur in profusion on one sole. Some show a circular outline indicating that they were preserved flat on the bedding plane, but others occur as semicircular reliefs oriented in the palaeocurrent direction. This indicates that they too were moved by the turbidity current, but their abundance and excellent preservation indicate that transport distances were short. There is no evidence in either genus for the coelenterate characteristics of a mouth and a two-layered body wall enclosing a single cavity. This, and the evidence for a rigid outer wall, adds to recent doubt on the concept of the world-wide Ediacaran fauna as dominated by soft-bodied coelenterates.

Multiple episodes of extensional tectonism dominated the formation of Mesozoic fault-bounded basins on the Grand Banks of Newfoundland, the Irish Continental Shelf and the central North Sea. A range of structural and stratigraphic responses in the Jeanne d'Arc, Porcupine and Moray Firth basins support widespread synchronous tectonic controls on sedimentation during one of these episodes, the Late Cimmerian. Rifting was preceded by a phase of related tectonism during which subsidence rates began to vary across broad areas but without significant fault block rotation. This Late Cimmerian ‘onset warp’ pattern of subsidence is considered to have been essential in the establishment of restricted anoxic basins from latest Oxfordian through Kimmeridgian (sensu gallico) time and the development of one prolific layer of organic-rich source rocks. The most prominent and widely recognized structural/lithostratigraphic response to Late Cimmerian rifting was the deposition of sediment wedges. Tithonian to early Valanginian strata generally thicken- into northerly trending faults in the Jeanne d'Arc and Porcupine basins, indicating that extensional stress was orientated WNW-ESE across a very broad area. The misalignment of this regional Late Cimmerian extensional stress with local inherited structural fabric may be responsible for transpressional uplift of individual fault blocks in the Outer Moray Firth basin. Sedimentological responses to Late Cimmerian rifting were varied, though a common lithofacies stacking pattern is recognized. Variably thick conglomerates and/or sandstones were widely deposited at the start of rift deformation, while palaeoenvironments ranged from alluvial and braid plain to submarine fan even within individual basins. The relatively coarse basal sediments fine upwards into a second layer of commonly organic-rich shales and mark The widest variations in palaeoenvironments and sediment thicknesses occurred during the last phase of Late Cimmerian rift tectonism, though all three basins show evidence of decreasing water depths, increasing oxygen levels and increasing grain size. This lithofacies stacking pattern of relatively coarse to fine to coarse (reservoir/source/reservoir) and the development of bounding unconformities are largely attributable to progressive changes in rift-controlled subsidence. Rift basin subsidence rates are interpreted to increase from a low at initiation of faulting to a mid-rift peak, followed by slowing subsidence to the end of extension. A number of counteracting crustal mechanisms that may account for progressive variations in rift-induced subsidence are considered.

Minor amounts of authigenic pyrite are common throughout the Middle Jurassic Brent Group, often being well developed within the delta-plain fades of the Ness Formation. Petrographic analyses of pyrite samples from the Lyell and Murchison fields reveal two stages of pyrite authigenesis, both of which occurred during an early stage of burial. The first phase of pyrite authigenesis is represented by the development of nodules and finely-disseminated cement within shale, mudstone, and siltstone fades, and can include the development of bladed marcasite nodules. These cements are interpreted as having formed within organic-rich sediment soon after deposition, and pre-date all other authigenic precipitates (typically calcite, quartz and kaolinite). “Early” pyrite cements display a wide range of δ34S(-14.9 to +42.5% CDT), and some nodules analysed display isotopically-heavy cores and considerably lighter margins. These isotopically-zoned nodules are problematical. They could be interpreted as forming via progressive “closed system” bacteriogenic reduction and isotopic fractionation of sea-water sulphate, with incorporation of heavy H2S into the earliest-formed pyrite occurring as a result of its upward diffusion through the sediment column, following isotopic fractionation at depth. However, there are a number of problems with this type of interpretation. These include the fact that diffusion will favour the 32S isotope, so that the first-formed cements should still be isotopically “light” not “heavy”; also, there is a mass-balance problem, in that no low δ34S sulphides were detected. Coarsely-crystalline pyrite euhedraform nodular cements mainly within sandstones (δ34S -2.6 to +12.8%CDT), and are interpreted as a “later” diagenetic phase. This second phase of sulphide cementation also pre-dates the main phases of quartz and kaolinite authigenesis within sandstones, but post-dates an early phase of kaolinite, and may have been partly coeval with some early calcite authigenesis. High organic contents and the early establishment of reducing conditions led to early formation of pyrite within fine-grained brackish and marine sediments. The lowest measured end-member δ34S of sandstone-hosted pyrite cements is less isotopically depleted than that within fine-grained argillaceous fades, perhaps indicating that sandstone-hosted pyrite cements began to form subsequent to the onset of burial and bacteriogenic reduction within mudstones. Compaction of marine/brackish-water shales and mudstones (or sulphate diffusion from these fades) may have supplied an already isotopically-fractionated source of sulphate to porous sandstone lithologies, where “later” pyrite cements precipitated.

Raman spectroscopy is steadily growing in importance in the industrial analytical laboratory. The nature of the equipment, its ease of use and its cost are making the method more acceptable to non-experts. This paper illustrates the capabilities of a recent commercialized Raman system which fulfils the criteria of ease of use, speed and low cost. The system is designed for Raman microscopy and uses a single spectrograph and CCD detector. The combination provides confocal microscopy, high throughput and optimum sensitivity, to the extent that it only requires the use of a low-powered laser to provide high-quality spectral data. The additional feature of direct Raman imaging is seen as being beneficial in the industrial environment in that it provides spatial information over large surface areas quickly and without the need for excessive amounts of data processing. The performance of the instrument is illustrated with applications taken from the industrial environment.

The combination of the three types of vibrational spectroscopy, infrared, Raman, and inelastic neutron scattering, has enabled all of the internal, and most of the external, modes of Mg2FeH6 and Mg2FeD6 to be observed and assigned, as well as some of the modes of Mg2FeD5H. As an aid to the assignment, a reliable, empirical force field has been developed. The spectra also show evidence for a dynamic distortion of the hexahydrido complex, an effect that is not observed for the deuterated species.

The infrared, Raman and inelastic neutron scattering spectra of the approximately tetrahedral ternary metal hydrides: Mg2NiH4, Rb3ZnH5 and their deuterides have been observed and assigned. This has enabled a comparison of some of the properties of the first row transition ternary metal hydrides.

Fourier transform Raman spectroscopy has been carried out remote from the instrumentation using fibre-optic probes. The quality of the data is good; the measured signal-to-noise ratios from spectra obtained using a conventional sampling arrangement are better only by a factor of ca. 5. The choice of fibre-optic material and grade is crucial to the success of this work. Two different fibres have been tested and compared. Technical improvements are discussed.

The fourier transform (FT) Raman method, the main technique for overcoming background fluorescence in Raman spectroscopy, was applied to small samples which proved difficult to study using visible laser Raman methods. Various examples are given and the minimum sample size for FT-Raman spectroscopy has been shown to be in the microgram range.

The present work has provided a complete set of assignments for the vibrational spectrum of Rb2PtH6 and Rb2PtD6. To confirm the assignments, a periodic density functional theory (DFT) code has been applied to the analysis of the inelastic neutron scattering (INS) spectrum of an ionic material for the first time. The work has also provided an explanation for the unusual infrared spectrum of the potassium salt. The most significant aspect of the work is the use of the momentum transfer information provided by an INS chopper spectrometer. The straightforward method employed for the analysis of the data is applicable to any molecular system (organic or inorganic) and demonstrates the potential of these instruments for chemistry. Periodic DFT was also used to study the other A2PtH6 (A = alkali metal) including, the at present, unknown Li salt, which is found to be stable. The DFT studies have also highlighted the crucial role of the cation in removing charge from the transition metal and “hydride” ligand. It i...

Summary A 79-year-old man with a diagnosis of myocardial infarction treated with streptokinase and heparin developed a large lingual haematoma, precipitating dysphagia and upper airway obstruction. Spontaneous haemorrhage into the tongue is a previously unreported but serious complication of thrombolytic therapy. Tracheal intubation was performed under local anaesthesia.

Raman spectroscopic studies have been carried out on a rhenium/alumina catalyst, active in metathesis reactions. Raman data comparing the state of the rhenium on the fresh catlyst (freshly activated and following air exposure), and on catalyst promoted with tetramethyltin are presented.The ammonium perrhenate impregnated alumina catalyst precursor contains a tetrahedral oxidic rhenium species in a hydrated state. When the precursor is activated, a reduction in the number of attached hydroxyl groups and a distortion of the tetrahedral rhenium moiety occurs. The extent of hydration of the rhenium phase is therefore an important parameter determining metathesis activity. There is no evidence for the presence of a surface rhenium heptoxide phase.An extra Raman band at 777 cm–1, observed following tetramethyltin promotion, is attributed to a Re–Sn vibration. This Re–Sn interaction may be responsible for the observed promotional effect.

In situ Raman spectroscopic studies of the electrochemical reduction of carbon dioxide at lead-impregnated PTFE-bonded carbon gas diffusion electrodes are reported. Polarization of the electrode surface resulted in the appearance of two weak bands at 2824 and 2915 cm−1. These do not correspond to the wavenumber shifts expected for free formic acid, but they are thought to arise from the presence of a ‘free’ formate ion and the formic acid perturbed at the electrode surface, respectively. Spectral changes observed at lower wavenumber shifts on polarization of the electrodes are interpreted in terms of the reduction of lead oxide to lead.

The free radical cations of a series of para- substituted anilines have been formed by UV photolysis of the neutral parent compounds trapped in clear glassy ethanol matrices at 77 K. The radicals all have intense visible absorption bands which facilitate excitation of their resonance Raman spectra. These Raman spectra have been assigned and interpreted in terms of structure changes from the corresponding parents. The changes are shown to correlate well with the appropriate Hammett σp function values for the para-substituents.

The Red Marls are renamed the Milford Haven Group (thickness approximately 2 · 4 km) and divided between the Red Cliff, Albion Sands, Lindsway Bay, Sandy Haven and Gelliswick Bay Formations, in ascending order. The lowest three, totalling approximately 230 m in thickness, are largely restricted to the Marloes area, where they succeed the marine Silurian rocks sharply and with a distinct facies change, indicative of a possibly substantial stratigraphical break. Northwards the Red Cliff and Albion Sands Formations are overlapped, the Lindsway Bay Formation in the Winsle area resting disconformably on marine Silurian rocks older than the youngest of the marine Silurian beds exposed at Marloes. The Sandy Haven and Gelliswick Bay Formations are more widely distributed and closely resemble the Red Marls of the Pembroke Peninsula and the main outcrop north of the Benton Fault. They are Gedinnian in age on the basis of ostracoderms, but the Gelliswick Bay Formation may range into the Siegenian. The thick Cosheston Group, which grades up from the Gelliswick Bay formation, probably represents the remainder of the Siegenian and may possibly be partly Emsian in age. The character of the Milford Haven Group lends no credence to the idea that allochthonous blocks are assembled in southwest Dyfed as the result of Variscan movements.

The free radical cation of 1,4-diaminobenzene (p-phenylenediamine, PPD+.) has been generated in aqueous solution, wherein it is short-lived, by oxidation of the parent compound with bromine. The same PPD+. radical has also been produced by UV photolysis of the parent at 77 K in an ethanolic glassy matrix. Resonance Raman spectra of the radical and its parent are reported and analysed in detail with the aid of normal coordinate and molecular orbital calculations. Evidence is presented for (PPD+.)2 dimer formation in aqueous solution at room temperature.

The 5-10-dihydrophenazine and the 5-methyl-10-hydrophenazine free radical cations have been prepared at room temperature by photolysis of phenazine and 10-methylphenazine, respectively, in acidic ethanol solution. Both radicals exhibit very intense visible absorptions which have permitted the excitation of their resonance Raman spectra. Raman spectra have been recorded using various laser exciting lines, and excitation profiles for both systems have been determined. The parent-to-radical wavenumber shifts observed for each species have been interpreted in terms of the structural changes brought about by radical formation.

SUMMARY. A simple 4π light collector is described suitable for light attenuation studies. It uses table tennis balls as light collectors and its spherical response is near to ideal. A circuit for a simple meter based on an operational amplifier is given as well as that for a direct-reading log-ratio meter. Both circuits are intended for use with selenium photocells. The cost of the materials for detector and simple meter is less than £30.

SUMMARY Freshly exposed unameliorated spoil and vegetated spoil were analysed for their nitrogen constituents using methods devised for soils. The main components found were non-exchangeable ammonium (25%), hydrolysable nitrogen (33%) and unidentified non-hydrolysable nitrogen (62%). Summation of these exceeded 100% because hydrolysis with 6 M HCI extracted much of the non-exchangeable ammonium. Ammonium in the hydrolysate accounted for over 90% of hydrolysable nitrogen in freshly exposed unameliorated spoil and 70% of hydrolysable nitrogen in vegetated spoil. Correction for this ammonium in the hydrolysate allowed estimates of ‘recent organic’ nitrogen accumulation to be made. These estimates were significantly correlated with spoil mineralizable nitrogen levels. The nature of the nitrogen constituents of colliery spoil and the use of ‘recent organic’ nitrogen estimates in assessing site fertility are discussed.

The full resonance Raman spectra of cobalt(II) and cobalt(I) phthalocyanine are presented. By comparison with the Raman spectra of similar compounds, it has been possible to assign many of the bands. The resonance Raman spectrum of cobalt(II) phthalocyanine was replaced by that of cobalt(I) phthalocyanine when a PTFE-bonded carbon gas diffusion electrode impregnated with a small amount of cobalt(II) phthalocyanine was maintained at a potential of −1.80 V, the gas side of the electrode being exposed to a carbon dioxide atmosphere. These results indicate that cobalt(I) phthalocyanine is a reactive intermediate in the electrochemical reduction of carbon dioxide to carbon monoxide at cobalt(II) phthalocyanine-impregnated electrodes.

The synthesis of 2-nitrophenanthrene from 9,l0-dihydrophenanthrene is reported. Some 2-substituted phenanthrene and 9,l0-dihydrophenanthrene hydroxylamine derivatives have been prepared and the structure of the rearrangement products determined.

The utilization of amino acid benzyl esters in synthetic peptide procedures offers advantages over the corresponding methyl or ethyl derivatives. Whereas the latter groups must by cleaved by alkaline saponification, the benzyl ester function can be removed by acidolysis or by catalytic hydrogenation under conditions which permit the simultaneous cleavage of N-acyl-protecting groups such as t-Boc or CBzl.*