1,452 research outputs found

    Studies of Complex Formation in the System Chromium(III) - Phosphoric Acid.

    Get PDF
    The aim of the work described in this thesis has been to further the existing knowledge of the chromium (lll) - phosphoric acid system in aqueous media. Because of the length of time required for the system to attain equilibrium at room temperature, the majority of the solutions investigated were aged at 70°C. Methods for deciding whether equilibrium had in fact been reached were determined. At 70°C, a phase diagram study of the system Cr[2]O[3]-P[2]O[5]-H[2]O gave a series of parallel tie-lines and no compound could be isolated as such, A preliminary investigation into the nature of the solid material indicated that it behaved as an ion exchanger. Possible structures have been put forward. The results of ion-exchange studies carried out on both saturated and unsaturated solutions of the system indicated the existence of polynuclear species. The batch studies using cation exchange resins of varying degrees of cross-linking show that there is a marked 'sieving out' effect where the cross-linking is heavy. From the chromatographic separations employing the technique of gradient elution the PO[4] : Cr ratio of a number of these complexes have been evaluated. Probable structures have been allocated to these 7 complexes. Modes of formation have also been discussed. The structure of the cationic complexes existing in solution and the nature of the solid phase in contact with a saturated solution are discussed in terms of a concept of "-olation" which is held to be capable of extension

    The role of EcoCampus in addressing sustainability in UK universities

    Get PDF
    Universities are key drivers of sustainable development and are well-positioned to contribute to the sustainability agenda. Universities in the United Kingdom (UK) are themselves large and influential organisations, and because of their size, can have a significant impact on the environment. Their challenge, however, is to practice what they preach and to manage their own estates and procurement decisions to reduce their impact on the environment and meet carbon reduction targets. In the UK, higher education (HE) sector Scopes 1 and 2 carbon CO2e emissions have, over recent years, been falling considerably short of the emission reduction targets set by the Higher Education Funding Council for England (HEFCE) in all but a few institutions. Setting sector specific targets, therefore, does not guarantee success in addressing climate change. However, in those institutions adopting the EcoCampus management system approach, Scopes 1 and 2 carbon CO2e emissions have fallen by up to 5% over the latest reporting period (2013/2014–2014/2015). This contrasts with the increase in emissions from those institutions who currently do not have a certified management system and are currently at the bottom of the People and Planet University League Table. (This is an independent league table of UK universities ranked by environmental and ethical performance). Environmental management systems (EMSs) are increasingly being used by organisations to improve their environmental performance. EMSs deliver many benefits such as reducing resource use and pollution, complying with relevant environmental legislation, managing risks, improving corporate reputation and saving costs. The aim of this research was to assess the carbon management performance of universities in the UK and China and relate this to the level of uptake of EMSs in these universities. The results of this research informed the development of the EMS support and awards programme called EcoCampus. EcoCampus addresses the challenges faced by universities in reducing their carbon emissions by developing an EMS in simple stages with support in a variety of different forms. This self-financing programme has now been operating successfully for over ten years. During this time, EcoCampus has worked with over 60 universities and colleges in the UK. Eighteen participants have currently achieved the highest phase of EcoCampus and certification to the international EMS standard ISO14001. There are currently 40 universities, one research institute and three colleges enrolled on the various phases of the EcoCampus programme. There are five universities from the Russell Group including Cambridge University, Imperial College London, Nottingham University, Newcastle University and University College London. The EcoCampus programme is highly successful in the UK and there is growing interest from international universities wishing to join the programme. Seven of the top ten universities in the UK’s People and Planet University League Table are EcoCampus members. All the top ten universities in the League Table have shown a reduction in their carbon emissions. In contrast, the ten institutions at the bottom of the League don’t have a certified EMS and have increased their carbon emissions. By identifying the benefits of an EMS, particularly in relation to carbon management, it is hoped that this paper will encourage organisations to develop, implement and operate an EMS. This should lead to a more sustainable sector able to lead by example

    Tissue biochemical diversity of 20 gooseberry cultivars and the effect of ethylene supplementation on postharvest life

    Get PDF
    The European gooseberry (Ribes uva-crispa) is still an understudied crop with limited data available on its biochemical profile and postharvest life. A variety of polyphenols were detected in the skin and flesh of 20 gooseberry cvs, representing mainly flavonol glycosides, anthocyanins and flavan-3-ols. In contrast, gooseberry seeds were for the first time characterised by the presence of considerable amounts of hydroxycinnamic acid glycosides tentatively identified by UPLC-QToF/MS. All cvs examined represented a good source of vitamin C while being low in sugar. Furthermore, the postharvest stability of bioactives was explored by supplementation of exogenous ethylene in air at 5 °C. Results suggest a low sensitivity of gooseberries to ethylene. The overall quality of gooseberries remained stable over two weeks, showing potential for extended bioactive life

    Quantification of the photosynthetic performance of phosphorus-deficient Sorghum by means of chlorophyll-a fluorescence kinetics

    Get PDF
    Chlorophyll fluorescence induction curves have been used as a sensitive tool for screening the photosynthetic performance of plants. Experimental treatments involving nitrate supply and chilling stress have been shown to affect fluorescence induction curves and other measures of photosynthesis. We have investigated the photosynthetic performance of Sorghum bicolor supplied with Long Ashton growth solution containing standard (20 μmol mol^(–1)) or low (5 μmol mol^(–1)) phosphorus. The JIP-test based on the chlorophyll fluorescence induction curve was used as a non-destructive method to measure the relative proportions of energy dissipated by different processes (termed energy fluxes) in the light reactions. The various energy fluxes or derived parameters were compared to find the measures that were most sensitive to the experimental conditions. Plant response to treatments was first evident in selected chlorophyll fluorescence parameters, particularly performance index (PI_ABS_); plants with increased PI_ABS_ manifested higher electron transport activity and dissipated less energy as heat, possibly as a result of their better phosphorus status, leading to more functional reaction centres. Observed changes in fluorescence were correlated to changes in gas exchange and biomass. Standard phosphorus treatments significantly increased biomass, leaf area, photosynthetic and respiratory rates, carboxylation efficiencies and levels of ribulose biphosphate regeneration rates, relative to plants with low supplies of nutrients

    RESPOND – A patient-centred programme to prevent secondary falls in older people presenting to the emergency department with a fall: Protocol for a mixed methods programme evaluation.

    Get PDF
    Background Programme evaluations conducted alongside randomised controlled trials (RCTs) have potential to enhance understanding of trial outcomes. This paper describes a multi-level programme evaluation to be conducted alongside an RCT of a falls prevention programme (RESPOND). Objectives 1) To conduct a process evaluation in order to identify the degree of implementation fidelity and associated barriers and facilitators. 2) To evaluate the primary intended impact of the programme: participation in fall prevention strategies, and the factors influencing participation. 3) To identify the factors influencing RESPOND RCT outcomes: falls, fall injuries and ED re-presentations. Methods/ Design Five hundred and twenty eight community-dwelling adults aged 60–90 years presenting to two EDs with a fall will be recruited and randomly assigned to the intervention or standard care group. All RESPOND participants and RESPOND clinicians will be included in the evaluation. A mixed methods design will be used and a programme logic model will frame the evaluation. Data will be sourced from interviews, focus groups, questionnaires, clinician case notes, recruitment records, participant-completed calendars, hospital administrative datasets, and audio-recordings of intervention contacts. Quantitative data will be analysed via descriptive and inferential statistics and qualitative data will be interpreted using thematic analysis. Discussion The RESPOND programme evaluation will provide information about contextual and influencing factors related to the RCT outcomes. The results will assist researchers, clinicians, and policy makers to make decisions about future falls prevention interventions. Insights gained are likely to be transferable to preventive health programmes for a range of chronic conditions

    ‘Choicest unguents’: molecular evidence for the use of resinous plant exudates in late Roman mortuary rites in Britain

    Get PDF
    YesResinous substances were highly prized in the ancient world for use in ritual contexts. Details gleaned from classical literature indicate that they played a significant role in Roman mortuary rites, in treatment of the body and as offerings at the tomb. Outside of Egypt, however, where research has shown that a range of plant exudates were applied as part of the mummification process, resins have rarely been identified in the burial record. This is despite considerable speculation regarding their use across the Roman Empire. Focusing on one region, we investigated organic residues from forty-nine late Roman inhumations from Britain. Using gas chromatographyemass spectrometry and the well-attested biomarker approach, terpenic compounds were characterized in fourteen of the burials analysed. These results provided direct chemical evidence for the presence of exudates from three different plant families: coniferous Pinaceae resins, Mediterranean Pistacia spp. resins (mastic/terebinth) and exotic Boswellia spp. gum-resins (frankincense/olibanum) from southern Arabia or beyond. The individuals accorded this rite had all been interred with a package of procedures more elaborate than the norm. These findings illuminate the multiplicity of roles played by resinous substances in Roman mortuary practices in acting to disguise the odour of decomposition, aiding temporary soft-tissue preservation and signifying the social status of the deceased. Nevertheless, it was their ritual function in facilitating the transition to the next world that necessitated transportation to the most remote outpost of the late Roman Empire, Britain.R.C.B is supported by a PhD studentship from the Art and Humanities Research Council (43019R00209)
    • …
    corecore