2,936 research outputs found
The Recognition of Fires Originating from Photovoltaic (PV) Solar Systems
No full textThere has been an observable increase in the fitting of photovoltaic (PV) solar panels on the roofs
of buildings in the UK over the last decade. The origin of some fires in domestic and commercial
properties has been attributed to PV systems. This thesis examines the ability of fire examiners to
recognise and record details of fires believed to have originated from PV systems, as well as
investigating the effect of internal heating in direct current (DC) isolators to the point at which they
fail.
National fire data was examined along with the methods for collecting and collating these data.
This clarified that national fire data cannot identify the specifics of electrical fires. Validity of these
data was then tested by identifying the confidence and competence in the recognition of the origin
of fire, (especially when associated with PV systems), of some fire staff responsible for collecting
fire data. This suggests that some fire scenes examiners are not confident in their own ability to
recognise fires originating from PV systems. Evidence for fires occurring in PV systems in Kent
between 2009 and 2014 was then examined, including a cold case forensic review of the
evidence. This provided an indication that a potential common point of failure, which may lead to
fire originating from a PV system, was to be found within the DC section of the PV circuits and
probably within the DC isolator switch itself. Experimentation revealed that internal heating of a
terminal connection can lead to changes of the phase of the insulating material, causing failure of
structural integrity and therefore allowing an arc to be established. Observable post fire indicators
associated with this mechanism of failure have been identified as well as hydrocarbons evolved
from pyrolysis of isolator insulating material.
Finally, areas for further experimental research and training of fire staff are suggested as well as
the modification of recording mechanisms and building regulations
Properties and prospects for rhenium(i) tricarbonyl N-heterocyclic carbene complexes
No full textRe(i) complexes bound to p-conjugated bidentate N-heterocyclic carbene ligands with formulation Re(CO)3(N^NHC)L (where N^NHC represents an imidazole or benzimidazole carbene ligand conjugated to a N-based heterocycle such as pyridine, pyrimidine, quinoline or quinoxaline) are a relatively new class of complexes belonging to the archetypal family of well known luminescent Re(CO)3(diim)X species (where diim is a conjugated diimine ligand and X is a halogen anion). The complexes Re(CO)3(N^NHC)L are characterised by blue-shifted emission compared to Re(CO)3(diim)X, but with shorter excited state lifetime decays and lower quantum yields, in contrast to trends expected by the energy gap law. Detailed investigations elucidated that these complexes are photochemically active and undergo ligand exchange reactions when excited to their lowest metal-to-ligand charge transfer excited states. This mechanism is entirely different from previously known mechanisms of photoactivated ligand substitution reactions in Re(i) tricarbonyl complexes. Therefore, the species Re(CO)3(N^NHC)L represent a new and unique class of photoactive Re(i) complexes. This feature article illustrates the research effort dedicated to the design and synthesis of Re(CO)3(N^NHC)L complexes and the elucidation of their photophysical and photochemical behaviour by means of a variety of spectroscopic techniques. Furthermore, for their unique characteristics, these new complexes have demonstrated potential value in several applications including catalysis, diagnosis and therapy. These studies will also be illustrated herein
Feasibility of Solar Technology (Photovoltaic) Adoption: A Case Study on Tennessee's Poultry Industry
No full textThe advantages and limitations of solar photovoltaic (PV) systems for energy generation are reviewed under various physical efficiency limits, operational design and financial assistance programs. Recent increases in utility and fuel costs in poultry production as well as public awareness of and demand for green power or renewable energy sources has given renewed interest in alternative energy sources. This study seeks to investigate the impact of alternative energy programs, grants and other incentives on the feasibility of solar PV systems in two solar regions within Tennessee's poultry industry. Preliminary results show that incentives must exceed current levels before adoption of solar PV systems would be financially beneficial.Livestock Production/Industries, Resource /Energy Economics and Policy,
Solar PV hosting capacity: Grid-based vs. market-based scenarios
No full textAssessing the capability of a distribution grid to accommodate new solar PV installations, namely its hosting capacity (HC), has been a prevalent research topic. Although providing a technical limit to how much additional solar PV can be integrated into a distribution grid without trespassing operational limits, commonly used HC analysis (HCA) does not consider consumer preferences or the economic feasibility of installations. Using a market-based optimal power flow (MBOPF) and HCA, we compare the economic and technical limits of solar PV capacity integration in low voltage distribution systems (LVDS). Findings illustrate that (1) the PV HC computed using grid limits only does not give a complete picture of solar PV capacity integration potential, (2) linear, deterministic power flow is not a foolproof method for assessing the network-secure amount of PV, and (3) the number of technically feasible installation sites supersedes the economically feasible ones.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Energy and Industr
Unprecedented staining of polar lipids by a luminescent rhenium complex revealed by FTIR microspectroscopy in adipocytes
No full textData source: Supplementary information, http://www.rsc.org/suppdata/c6/mb/c6mb00242k/c6mb00242k1.pdfFourier transform infrared (FTIR) microspectroscopy and confocal imaging have been used to demonstrate that the neutral rhenium(i) tricarbonyl 1,10-phenanthroline complex bound to 4-cyanophenyltetrazolate as the ancillary ligand is able to localise in regions with high concentrations of polar lipids such as phosphatidylethanolamine (PE), sphingomyelin, sphingosphine and lysophosphatidic acid (LPA) in mammalian adipocytes.C. A. Bader, E. A. Carter, A. Safitri, P. V. Simpson, P. Wright, S. Stagni, M. Massi, P. A. Lay, D. A. Brooksa and S. E. Plus
PV-boats: Design issues in the realization of PV powered boats
No full textPV integration in boats is rarely seen, but offers clean and silent transportation while on the water. In order to research the PV realization into boat design challenges, the University of Twente and the NHL hogeschool, both in the Netherlands, started a joined research into PV integration in boats. By studying 3 cases, PV boat specifications and the key design challenges are researched. The first case, the Frisian Solar Challenge 2010, offered the possibility to gather information about 44 innovative PV powered racing boats. The Frisian Solar Challenge is a 5 day 220km race for PV powered boats. Boats need to be fast, efficient and reliable to finish the race at high positions. The second case shows the NHL hogeschool\u92s PV powered racing boat design and building process which attended the Frisian Solar Challenge 2010. The third case is a study in PV powered boats found worldwide. From 105 boats, specifications are collected to learn recent developments in PV powered boats. From these 3 cases follows that light weight is one of the key parameters to build a successful PV powered boat. Especially PV modules with lower weight can bring successful PV powered boat designs. Furthermore, boats equipped with monohull designs offer high efficiency with low drag. However, catamaran designs prove to be successful as well, bringing higher stability in boat designs. Mature technology is needed to sail with reliable hardware
Comprehensive modelling and sizing of PV systems from location to load
No full textPhotovoltaic (PV) systems are progressively used for decentralized electricity generation. To obtain the maximum yield from such systems, optimisation of all components is essential. In this contribution, we provide a comprehensive modelling and sizing of PV systems for any location. Three applications are here presented providing real time monitoring of PV potential, accurate prediction of yield taking into account thermodynamic temperature effects, optimization of modules orientation addressing the effects of shading and efficient sizing of inverter for a higher yield output. When combined, these models can accurately predict the real time performance of any PV system.Accepted Author ManuscriptPhotovoltaic Materials and DevicesDC systems, Energy conversion & Storag
Xanthomonas campestris pv. campestris (cause of black rot of crucifers) in the genomic era is still a worldwide threat to brassica crops
No full textBackground
Xanthomonas campestris pv. campestris (Xcc) (Pammel) Dowson is a Gram-negative bacterium that causes black rot, the most important disease of vegetable brassica crops worldwide. Intensive molecular investigation of Xcc is gaining momentum and several whole genome sequences are available.
Taxonomy
Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadacea; Genus Xanthomonas; Species X. campestris.
Host range and symptoms
Xcc can cause disease in a large number of species of Brassicaceae (ex-Cruciferae), including economically important vegetable Brassica crops and a number of other cruciferous crops, ornamentals and weeds, including the model plant Arabidopsis thaliana. Black rot is a systemic vascular disease. Typical disease symptoms include V-shaped yellow lesions starting from the leaf margins and blackening of the veins.
Race structure, pathogenesis and epidemiology
Collections of Xcc isolates have been differentiated into physiological races based on the response of several brassica species lines. Black rot is a seed-borne disease. The disease is favoured by warm, humid conditions and can spread rapidly from rain dispersal and irrigation water.
Disease control
The control of black rot is difficult and relies on the use of pathogen-free planting material and the elimination of other potential inoculum sources (infected crop debris and cruciferous weeds). Major gene resistance is very rare in B. oleracea (brassica C genome). Resistance is more readily available in other species, including potentially useful sources of broad-spectrum resistance in B. rapa and B. carinata (A and BC genomes, respectively) and in the wild relative A. thaliana.
Genome
The reference genomes of three isolates have been released. The genome consists of a single chromosome of approximately 5 100 000 bp, with a GC content of approximately 65% and an average predicted number of coding DNA sequences (CDS) of 4308.
Important genes identified
Three different secretion systems have been identified and studied in Xcc. The gene clusters xps and xcs encode a type II secretion system and xps genes have been linked to pathogenicity. The role of the type IV secretion system in pathogenicity is still uncertain. The hrp gene cluster encodes a type III secretion system that is associated with pathogenicity. An inventory of candidate effector genes has been assembled based on homology with known effectors. A range of other genes have been associated with virulence and pathogenicity, including the rpf, gum and wxc genes involved in the regulation of the synthesis of extracellular degrading enzymes, xanthan gum and lipopolysaccharides
PV Module Integrated Converter for Distributed MPPT PV Systems
No full textDriven by constant advances and cost reductions in photovoltaic (PV) technology,together with incentive government policies toward cleaner environment, the PV energy became one of the fastest growing market in the world. In many countries the amount of installed PV power is increasing at an exponential rate, in all sectors from large utility scale power plants to small residential PV systems.DC systems, Energy conversion & Storag
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