23 resultados para conducting textiles
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
The reversibility of zinc anode in alkaline medium was enhanced by electrostatic deposition of a conducting polymer (polypyrrole). Electropolymerization of pyrrole onto zinc in aqueous medium using an organic acid as dopant is feasible and preferred as zinc is less corrosive in this medium. The structure of the polymer film was analyzed by FT-IR spectroscopy and scanning electron microscopy. The effect of the polypyrrole deposit on the zinc electrode was studied by cyclic voltammetry and charge–discharge cycling.
Resumo:
Aromatic monomers can be polymerised using the chloroaluminate room temperature melt obtained by mixing 1:2 ratio of cetyl pyridinium chloride and anhydrous aluminium chloride miscible in all proportions with organic solvents as an electrolyte. The chloroaluminate (AlCl4-) anion generated in this melt having a tetrahedral symmetry with equal bond lengths and bond angles is the dopant to stabilize macrocation generated near the vicinity of anode to yield better conducting and better ordered electronically conducting free standing polymer film. In this communication, we discuss the polymers derived from benzene and pyrrole and their characterization by various techniques.
Resumo:
Freestanding polyparaphenylene films were obtained on polymerization of benzene at potential of 1.2 V versus Al wire on substrates like platinum/transparent conducting glass as an anode. The electrolyte used was chloroaluminate room-temperature melt, which was prepared by intimate mixing of a 1:2 ratio of cetyl pyridinium chloride and anhydrous aluminum chloride to yield a viscous liquid. This liquid was miscible in all proportions with benzene and other aromatic hydrocarbons in all proportions at room temperature. The polyparaphenylene films deposited on platinum anode exhibited a prominent cyclic voltammetric peak at 0.7 V versus Al wire as reference electrode in chloroaluminate medium. The impedance spectra gave low charge transfer resistance. The diffused reflectance electronic spectra of the film gave the peaks at 386 nm and 886 nm. The PPP films showed electronic conductivity around 3–4 × 104 S/cm by four probe method under nitrogen atmosphere. The polymer was also characterized by IR spectra, thermal studies, and SEM studies.
Resumo:
Experimental and finite element modelling methods are used to study the formation of vapour layers in electrical discharges through saline solutions. The experiments utilize shadowgraphic and photometric methods to observe the time dependence of thin vapour layers and plasma formation around electrodes driven by moderate voltage (<500 V) pulses, applied to an electrode immersed in a conducting saline solution. Finite element multiphysics software, coupling thermal and electrical effects, is employed to model the vapour layer formation. All relevant electrical and thermal properties of the saline are incorporated into the model, but hydrodynamic and surface tension effects are ignored. Experimental shadowgraph and modelling images are compared, as are current histories, and the agreement is very good. The comparison of experiment and modelling gives insight into both vapour layer production and subsequent plasma production. We show that, for example, superheating of the saline above its normal vaporization temperature may be playing a significant role in vapour formation. We also show that electric fields of approaching 10(7) V m(-1) can be achieved in the vapour layer.
Resumo:
PURPOSE: The purpose of this study is to pilot test the effectiveness of using recently developed clinical guidelines from Australia for conducting palliative care family meetings in Japan. METHODS: Palliative care family meetings were conducted using clinical guidelines with 15 primary family carers of cancer patients who were admitted to an acute care hospital in Japan. Using the pre-family meeting questionnaire, the primary carers were asked to write key concerns to discuss during the family meetings and rate their concerns via a numerical rating scale: how upset/worried they were about the problem, frequency in which problem occurs, life interference with the problem, and the confidence to deal with the problem. Within 3 days after the meeting, the primary carers were asked to complete the post-meeting questionnaire to evaluate the effectiveness of the family meeting. RESULTS: There was a significant improvement in family carers' psychological well-being in the post-meeting questionnaires compared to the pre-meeting questionnaires as follows: how upset/worried they were about the problem, t(14)?=?3.1071, p?
Resumo:
Background. Interdisciplinary research has been promoted as an optimal research paradigm in the health sciences, yet little is known about how researchers experience interdisciplinarity in practice. This study sought to determine how interdisciplinary research was conceptualized and operationalized from the researcher's perspective and to better understand how best to facilitate interdisciplinary research success. Methods. Key informant interviews were conducted with health researchers with expertise or experience in conducting interdisciplinary research. Interviews were completed either in person or over the telephone using a semi-structured interview guide. Data collection occurred simultaneously with data analysis so that emerging themes could be explored in subsequent interviews. A content analysis approach was used. Results. Nineteen researchers took part in this study. Interdisciplinary research was conceptualized disparately between participants, and there was modest attention towards operationalization of interdisciplinary research. There was one overriding theme, "It's all about relationships", that emerged from the data. Within this theme, there were four related subthemes: 1) Involvement in interdisciplinary research; 2) Why do I do interdisciplinary research?; 3) Managing and fostering interdisciplinary relationships; and 4) The prickly side to interdisciplinary research. Together, these themes suggest that the choice to conduct interdisciplinary research, though often driven by the research question, is highly influenced by interpersonal and relationship-related factors. In addition, researchers preferred to engage in interdisciplinary research with those that they had already established relationships and where their role in the research process was clearly articulated. A focus on relationship building was seen as a strong facilitator of interdisciplinary success. Conclusion. Many health researchers experienced mixed reactions towards their involvement in interdisciplinary research. A well thought-out rationale for interdisciplinary research, and strategies to utilize the contribution of each researcher involved were seen as facilitators towards maximizing the benefits that could be derived from interdisciplinary research. © 2008 Nair et al; licensee BioMed Central Ltd.
Resumo:
Clinical psychologists often use qualitative methods to explore sensitive topics with vulnerable individuals, yet there has been little discussion of the specific ethical issues involved. For clinicians conducting qualitative research, there are likely to be ethical dilemmas associated with being both a researcher and a practitioner. We argue that this overarching issue frames all other ethical issues raised. This article provides an overview of the range of ethical issues that have been discussed in general in relation to qualitative research and considers the specific nature of these in relation to the discipline of clinical psychology. Such issues will be exemplified by reference to some of our own research and practice and the extant literature. We conclude with some suggestions for good practice, although our aim is to trigger debate rather than to establish prescriptive guidelines.
Resumo:
Tissue microarrays (TMAs) represent a powerful method for undertaking large-scale tissue-based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA-based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA-based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA-based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1-day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA-based research, including the pre-analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.
Resumo:
One of the difficulties with using molecularly imprinted polymers (MIPs) and other electrically insulating materials as the recognition element in electrochemical sensors is the lack of a direct path for the conduction of electrons from the active sites to the electrode. We have sought to address this problem through the preparation and characterization of novel hybrid materials combining a catalytic MIP, capable of oxidizing the template, catechol, with an electrically conducting polymer. In this way a network of "molecular wires" assists in the conduction of electrons from the active sites within the MIP to the electrode surface. This was made possible by the design of a new monomer that combines orthogonal polymerizable functionality; comprising an aniline group and a methacrylamide. Conducting films were prepared on the surface of electrodes (Au on glass) by electropolymerization of the aniline moiety. A layer of MIP was photochemically grafted over the polyaniline, via N,N'-diethyldithiocarbamic acid benzyl ester (iniferter) activation of the methacrylamide groups. Detection of catechol by the hybrid-MIP sensor was found to be specific, and catechol oxidation was detected by cyclic voltammetry at the optimized operating conditions: potential range -0.6 V to +0.8 V (vs Ag/AgCl), scan rate 50 mV/s, PBS pH 7.4. The calibration curve for catechol was found to be linear to 144 µM, with a limit of detection of 228 nM. Catechol and dopamine were detected by the sensor, whereas analogues and potentially interfering compounds, including phenol, resorcinol, hydroquinone, serotonin, and ascorbic acid, had minimal effect (=3%) on the detection of either analyte. Nonimprinted hybrid electrodes and bare gold electrodes failed to give any response to catechol at concentrations below 0.5 mM. Finally, the catalytic properties of the sensor were characterized by chronoamperometry and were found to be consistent with Michaelis-Menten kinetics. © 2009 American Chemical Society.