211 research outputs found
The feed-in tariff in the UK : a case study focus on domestic photovoltaic systems
This paper explores the photovoltaic (PV) industry in the United Kingdom (UK) as experienced by those who are working with it directly and with consideration of current standards, module efficiencies and future environmental trends. The government's consultation on the comprehensive review for solar PV tariffs, proposes a reduction of the generation tariff for PV installations in the UK of more than 50%. The introduction of the Feed-In Tariffs scheme (FITs) has rapidly increased deployment of PV technologies at small scale since its introduction in April 2010. The central principle of FIT policies is to offer guaranteed prices for fixed periods to enable greater number of investors. A financial analysis was performed on two real-life installations in Cornwall, UK to determine the impact of proposed cuts to the FIT will make to a typical domestic PV system under 4 kW. The results show that a healthy Return on Investment (ROI) can still be made but that future installations should focus on off-setting electricity required from the national grid as a long term push for true sustainability rather than subsidised schemes. The profitability of future installations will have to be featured within in-service and end-of-service considerations such as the feed-in tariff, module efficiencies and the implications of costs associated with end-of-life disposal
The effects of anode material type on the optoelectronic properties of electroplated CdTe thin films and the implications for photovoltaic application
The effects of the type of anode material on the properties of electrodeposited CdTe thin films for photovoltaic application have been studied. Cathodic electrodeposition of two sets of CdTe thin films on glass/fluorine-doped tin oxide (FTO) was carried out in two-electrode configuration using graphite and platinum anodes. Optical absorption spectra of films grown with graphite anode displayed significant spread across the deposition potentials compared to those grown with platinum anode. Photoelectrochemical cell result shows that the CdTe grown with graphite anode became p-type after post-deposition annealing with prior CdCl2 treatment, as a result of carbon incorporation into the films, while those grown with platinum anode remained n-type after annealing. A review of recent photoluminescence characterization of some of these CdTe films reveals the persistence of a defect level at (0.97–0.99) eV below the conduction band in the bandgap of CdTe grown with graphite anode after annealing while films grown with platinum anode showed the absence of this defect level. This confirms the impact of carbon incorporation into CdTe. Solar cell made with CdTe grown with platinum anode produced better conversion efficiency compared to that made with CdTe grown using graphite anode, underlining the impact of anode type in electrodeposition
Effect of iodine incorporation on characteristic properties of cadmium telluride deposited in aqueous solution
The electrodeposition of polycrystalline I-doped CdTe was successfully performed from aqueous solutions containing cadmium nitrate (Cd(NO3)2 and tellurium oxide (TeO2). The effects of different I-doping concentrations in the electrolytic bath on the deposited CdTe layers deposited were evaluated structurally, optically, morphologically and electronically using X-ray diffraction (XRD), ultraviolet-visible spectrophotometry, scanning electron microscopy, photoelectrochemical cell measurement and direct-current (DC) conductivity test respectively. The XRD show reduction in the (111) cubic CdTe peak intensity and the calculated crystallite size of the CdTe:I layers above 5 ppm I-doping. At I-doping of 1000 ppm of the CdTe-bath and above, the deposition of only crystalline Te due to the formation of Cd-I complexes debarring the deposition of Cd and co-deposition of CdTe in aqueous solution was observed. Morphologically, reductions in grain size were observed above 5 ppm I-doping with high pinhole density and the formation of cracks within the CdTe:I layers. For the as-deposited CdTe:I layers, conduction type remained n-type across all the explored I-doping concentration of 200 ppm. For the CdCl2 and Ga2(SO4)2+CdCl2 treated CdTe:I layers, the transition from n- to p-type conductivity was observed for the CdTe:I baths doped with 20 ppm and above due to the reduced cadmium deposition on the substrate. The highest conductivity was observed at 5 ppm I-doping of the CdTe-bath. Observations made on the CdTe:I in aqueous solution differs from the non-aqueous solvent documented in the literature. These results are reported systematically in this communication
Improvement of composition of CdTe thin films during heat treatment in the presence of CdCl2
CdCl2 treatment is a crucial step in development of CdS/CdTe solar cells. Although this rocessing step has been used over a period of three decades, full understanding is not yet achieved. This paper reports the experimental evidence for improvement of composition of CdTe layers during CdCl2 treatment. This investigation makes use of four selected analytical techniques; Photo-electro-chemical (PEC) cell, X-ray diffraction (XRD), Raman spectroscopy and Scanning electron microscopy (SEM). CdTe layers used were electroplated using three Cd precursors; CdSO4, Cd(NO3)2 and CdCl2. Results show the improvement of stoichiometry of CdTe layers during CdCl2 treatment through chemical reaction between Cd from CdCl2 and elemental Te that usually precipitate during CdTe growth, due to its natural
behaviour. XRD and SEM results show that the low-temperature (~85ºC) electroplated CdTe layers consist of ~(20-60) nm size crystallites, but after CdCl2 treatment, the layers show drastic recrystallisation with grains becoming a few microns in size. These CdCl2 treated
layers are then comparable to high temperature grown CdTe layers by the size of grains
Effects of deposition time and post-deposition annealing on the physical and chemical properties of electrodeposited CdS thin films for solar cell application
CdS thin films were cathodically electrodeposited by means of a two-electrode deposition system
for different durations. The films were characterised for their structural, optical, morphological
and compositional properties using x-ray diffraction (XRD), spectrophotometry, scanning
electron microscopy (SEM) and energy dispersive x-ray (EDX) respectively. The results obtained
show that the physical and chemical properties of these films are significantly influenced by the
deposition time and post-deposition annealing. This influence manifests more in the as-deposited
materials than in the annealed ones. XRD results show that the crystallite sizes of the different
films are in the range (9.4 – 65.8) nm and (16.4 – 66.0) nm in the as-deposited and annealed
forms respectively. Optical measurements show that the absorption coefficients are in the range
(2.7×104 – 6.7×104) cm-1 and (4.3×104 – 7.2×104) cm-1 respectively for as-deposited and annealed
films. The refractive index is in the range (2.40 – 2.60) for as-deposited films and come to the
value of 2.37 after annealing. The extinction coefficient varies in the range (0.1 – 0.3) in asdeposited
films and becomes 0.1 in annealed films. The estimated energy bandgap of the films is
in the range (2.48 – 2.50) eV for as-deposited films and becomes 2.42 eV for all annealed films.
EDX results show that all the films are S-rich in chemical composition with fairly uniform Cd/S
ratio after annealing. The results show that annealing improves the qualities of the films and
deposition time can be used to control the film thickness.
Keywords: Electrodeposition; two-electrode system; CdS; annealing; deposition time; thin-film
New directions for patient-centred care in scleroderma : the Scleroderma Patient-centred Intervention Network (SPIN)
Systemic sclerosis (SSc), or scleroderma,
is a chronic multisystem autoimmune
disorder characterised by
thickening and fibrosis of the skin and
by the involvement of internal organs
such as the lungs, kidneys, gastrointestinal
tract, and heart. Because there is
no cure, feasibly-implemented and easily
accessible evidence-based interventions
to improve health-related quality
of life (HRQoL) are needed. Due to a
lack of evidence, however, specific recommendations
have not been made
regarding non-pharmacological interventions
(e.g. behavioural/psychological,
educational, physical/occupational
therapy) to improve HRQoL in SSc. The
Scleroderma Patient-centred Intervention
Network (SPIN) was recently organised
to address this gap. SPIN is
comprised of patient representatives,
clinicians, and researchers from Canada,
the USA, and Europe. The goal
of SPIN, as described in this article, is
to develop, test, and disseminate a set
of accessible interventions designed to
complement standard care in order to
improve HRQoL outcomes in SSc.The initial organisational meeting for SPIN was funded by a Canadian Institutes of Health Research (CIHR) Meetings, Planning, and Dissemination grant to B.D. Thombs (KPE-109130), Sclerodermie Quebec, and the Lady Davis Institute for Medical Research of the Jewish General Hospital, Montreal, Quebec. SPIN receives finding support from the Sclemderma Society of Ontario, the Scleroderma Society of Canada, and Sclerodermie Quebec. B.D. Thombs and M. Hudson are supported by New Investigator awards from the CIHR, and Etablissement de Jeunes Chercheurs awards from the Fonds de la Recherche en Sante Quebec (FRSQ). M. Baron is the director of the Canadian Scleroderma Research Group, which receives grant folding from the CIHR, the Scleroderma Society of Canada and its provincial chapters, Scleroderma Society of Ontario, Sclerodermie Quebec, and the Ontario Arthritis Society, and educational grants from Actelion Pharmaceuticals and Pfizer. M.D. Mayes and S. Assassi are supported by the NIH/NIAMS Scleroderma Center of Research Translation grant no. P50-AR054144. S.J. Motivala is supported by an NIH career development grant (K23 AG027860) and the UCLA Cousins Center for Psychoneuroimmunology. D. Khanna is supported by a NIH/NIAMS K23 AR053858-04) and NIH/NIAMS U01 AR057936A, the National Institutes of Health through the NIH Roadmap for Medical Research Grant (AR052177), and has served as a consultant or on speakers bureau for Actelion, BMS, Gilead, Pfizer, and United Therapeutics
The Scleroderma Patient-centered Intervention Network (SPIN) Cohort : protocol for a cohort multiple randomised controlled trial (cmRCT) design to support trials of psychosocial and rehabilitation interventions in a rare disease context
Introduction: Psychosocial and rehabilitation
interventions are increasingly used to attenuate disability and improve health-related quality of life (HRQL) in chronic diseases, but are typically not available for patients with rare diseases. Conducting rigorous, adequately powered trials of these interventions for patients with rare diseases is difficult. The Scleroderma Patient-centered Intervention Network (SPIN) is an international collaboration of patient organisations, clinicians and researchers. The aim of SPIN is to develop a research infrastructure to test accessible, low-cost self-guided online interventions to reduce disability and improve HRQL for people living with the rare disease systemic sclerosis (SSc or scleroderma). Once tested, effective interventions will be made accessible through patient organisations partnering with SPIN. Methods and analysis: SPIN will employ the cohort multiple randomised controlled trial (cmRCT) design, in which patients consent to participate in a cohort for ongoing data collection. The aim is to recruit 1500– 2000 patients from centres across the world within a period of 5 years (2013–2018). Eligible participants are persons ≥18 years of age with a diagnosis of SSc. In addition to baseline medical data, participants will complete patient-reported outcome measures every 3 months. Upon enrolment in the cohort, patients will consent to be contacted in the future to participate in intervention research and to allow their data to be used for comparison purposes for interventions tested with other cohort participants. Once nterventions are developed, patients from the cohort will be randomly selected and offered interventions as part of pragmatic
RCTs. Outcomes from patients offered interventions will be compared with outcomes from trial-eligible patients who are not offered the interventions.
Ethics and dissemination: The use of the cmRCT design, the development of self-guided online interventions and partnerships with patient organisations will allow SPIN to develop, rigourously test and effectively disseminate psychosocial and rehabilitation interventions for people with SSc.(undefined
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