Optimization of Near Infrared Cured Polyester/Melamine Coil Coatings by the Use of Near Infrared Absorbing Primers

Near Infrared (NIR) radiative curing is a fastthermal curing technology used to cure 25 micron polyestermelamine industrial coil coatings on galvanized steel substrate.The cure is optimized when the top coat is relatively transparentto NIR and with most NIR absorption taking place at thesubstrate surface. In this study UV/Vis/NIR spectroscopy andlab scale curing trials with a white top coat were used to showthat absorption in the bottom most layers of the coating systemcan be taken a stage further by the addition of NIR absorbingpigment to the primer layer. The results show energy efficiencybenefits for NIR cure by increasing the amount of incidentradiation absorbed without altering the colour properties of thecoating. A similar smaller benefit is also evident with aconventional convection cure

Effect of TiO2 Photoanode Porosity on Dye Diffusion Kinetics and Performance of Standard Dye-Sensitized Solar Cells

Low-cost water-based P25-TiO2 pastes were formulated and used to produce porous TiO2 films in application to the fabrication of dye-sensitized solar cells. The structural properties of the films were characterized using a variety of techniques such as stylus profilometry, FEG-SEM imaging, BET surface area, and BJH pore size analyses. These were compared to films produced from a commercial paste, DSL 18 NR-AO (Dyesol). The major difference was in the fraction of macroporosity: 23% of the total pore volume for films produced with the commercial material and 67–73% for the P25-TiO2 films owing to the vast difference in dispersion and size distribution of the particles in the two types of pastes. The macroporosity was found to have a dramatic effect on the dye diffusion kinetics measured using in situ UV-Vis reflectance spectroscopy. The sensitization of P25-based films was much faster for heavily macroporous P25-TiO2 films (>90% saturation at 15–35 mins) than for their commercial analogue (>90% saturation at 110 mins). DSC devices built with optimized P25-TiO2 photoanodes showed better performance at short dye immersion time (30 mins and 1 hr) due to faster percolation of the dye molecules through the film

Sequential Slot-Die Deposition of Perovskite Solar Cells Using Dimethylsulfoxide Lead Iodide Ink

This work demonstrates a sequential deposition of lead iodide followed by methylammonium iodide using the industrially compatible slot-die coating method that produces homogeneous pin-hole free films without the use of the highly toxic dimethylformamide. This is achieved through the careful selection and formulation of the solvent system and coating conditions for both the lead iodide layer and the methylammonium iodide coating. The solvent system choice is found to be critical to achieving good coating quality, conversion to the final perovskite and for the film morphology formed. A range of alcohols are assessed as solvent for methylammonium iodide formulations for use in slot-die coating. A dimethylsulfoxide solvent system for the lead iodide layer is shown which is significantly less toxic than the dimethylformamide solvent system commonly used for lead iodide deposition, which could find utility in high throughput manufacture of perovskite solar cells

Middle and Late Pleistocene environmental history of the Marsworth area, south-central England

To elucidate the Middle and Late Pleistocene environmental history of south-central England, we report the stratigraphy, sedimentology, palaeoecology and geochronology of some deposits near the foot of the Chiltern Hills scarp at Marsworth, Buckinghamshire. The Marsworth site is important because its sedimentary sequences contain a rich record of warm stages and cold stages, and it lies close to the Anglian glacial limit. Critical to its history are the origin and age of a brown pebbly silty clay (diamicton) previously interpreted as weathered till. The deposits described infill a river channel incised into chalk bedrock. They comprise clayey, silty and gravelly sediments, many containing locally derived chalk and some with molluscan, ostracod and vertebrate remains. Most of the deposits are readily attributed to periglacial and fluvial processes, and some are dated by optically stimulated luminescence to Marine Isotope Stage (MIS) 6. Although our sedimentological data do not discriminate between a glacial or periglacial interpretation of the diamicton, amino-acid dating of three molluscan taxa from beneath it indicates that it is younger than MIS 9 and older than MIS 5e. This makes a glacial interpretation unlikely, and we interpret the diamicton as a periglacial slope deposit. The Pleistocene history reconstructed for Marsworth identifies four key elements: (1) Anglian glaciation during MIS 12 closely approached Marsworth, introducing far-travelled pebbles such as Rhaxella chert and possibly some fine sand minerals into the area. (2) Interglacial environments inferred from fluvial sediments during MIS 7 varied from fully interglacial conditions during sub-stages 7e and 7c, cool temperate conditions during sub-stage 7b or 7a, temperate conditions similar to those today in central England towards the end of the interglacial, and cool temperate conditions during sub-stage 7a. (3) Periglacial activity during MIS 6 involved thermal contraction cracking, permafrost development, fracturing of chalk bedrock, fluvial activity, slopewash, mass movement and deposition of loess and coversand. (4) Fully interglacial conditions during sub-stage 5e led to renewed fluvial activity, soil formation and acidic weathering

The impact of solvent characteristics on performance and process stability of printed carbon resistive materials

Carbon conductive pastes deposited by screen printing are used in many commercial applications including sensors, PCB, batteries, and PV, and as such represent an important value-added coating. An experimental investigation was carried out into the role of the solvent on the drying characteristics, conductivity, and process consistency in screen printed carbon pastes. Four materials with solvent boiling points between 166 and 219°C were deposited at film thickness between 6 and 16 μm, and the sheet resistance and film thickness were measured after successive passes through an industrial dryer operating with an air temperature of 155°C. Sheet resistances of 14 Ω/sq. were obtained with the thicker films while thinner films produced a sheet resistance of 46 Ω/sq. Thinner films achieved a stable resistivity within a 2.5-min residence time, while the thicker films required a residence time in excess of 12.5 min to achieve a stable resistivity. As well as prolonging drying times, the higher boiling point increased the resistivity of the cured film. It is postulated that the lower resistance of the faster drying materials is a result of film stressing increasing inter particle contact. Process models indicate that multiple thin layers are a more efficient means of manufacture for the process parameters examined

The availability of snack food displays that may trigger impulse purchases in Melbourne supermarkets

<p>Abstract</p> <p>Background</p> <p>Supermarkets play a major role in influencing the food purchasing behaviours of most households. Snack food exposures within these stores may contribute to higher levels of consumption and ultimately to increasing levels of obesity, particularly within socioeconomically disadvantaged neighbourhoods. We aimed to examine the availability of snack food displays at checkouts, end-of-aisle displays and island displays in major supermarket chains in the least and most socioeconomically disadvantaged neighbourhoods of Melbourne.</p> <p>Methods</p> <p>Within-store audits of 35 Melbourne supermarkets. Supermarkets were sampled from the least and most socioeconomically disadvantaged suburbs within 30 km of the Melbourne CBD. We measured the availability of crisps, chocolate, confectionery, and soft drinks (diet and regular) at the checkouts, in end-of-aisle displays, and in island bin displays.</p> <p>Results</p> <p>Snack food displays were most prominent at checkouts with only five stores not having snack foods at 100% of their checkouts. Snack foods were also present at a number of end-of-aisle displays (at both the front (median 38%) and back (median 33%) of store), and in island bin displays (median number of island displays: 7; median total circumference of island displays: 19.4 metres). Chocolate items were the most common snack food item on display. There was no difference in the availability of these snack food displays by neighbourhood disadvantage.</p> <p>Conclusions</p> <p>As a result of the high availability of snack food displays, exposure to snack foods is almost unavoidable in Melbourne supermarkets, regardless of levels of neighbourhood socioeconomic disadvantage. Results of this study could promote awareness of the prominence of unhealthy food items in chain-brand supermarkets outlets.</p

Design and implementation of a generalized laboratory data model

<p>Abstract</p> <p>Background</p> <p>Investigators in the biological sciences continue to exploit laboratory automation methods and have dramatically increased the rates at which they can generate data. In many environments, the methods themselves also evolve in a rapid and fluid manner. These observations point to the importance of robust information management systems in the modern laboratory. Designing and implementing such systems is non-trivial and it appears that in many cases a database project ultimately proves unserviceable.</p> <p>Results</p> <p>We describe a general modeling framework for laboratory data and its implementation as an information management system. The model utilizes several abstraction techniques, focusing especially on the concepts of inheritance and meta-data. Traditional approaches commingle event-oriented data with regular entity data in <it>ad hoc </it>ways. Instead, we define distinct regular entity and event schemas, but fully integrate these via a standardized interface. The design allows straightforward definition of a "processing pipeline" as a sequence of events, obviating the need for separate workflow management systems. A layer above the event-oriented schema integrates events into a workflow by defining "processing directives", which act as automated project managers of items in the system. Directives can be added or modified in an almost trivial fashion, i.e., without the need for schema modification or re-certification of applications. Association between regular entities and events is managed via simple "many-to-many" relationships. We describe the programming interface, as well as techniques for handling input/output, process control, and state transitions.</p> <p>Conclusion</p> <p>The implementation described here has served as the Washington University Genome Sequencing Center's primary information system for several years. It handles all transactions underlying a throughput rate of about 9 million sequencing reactions of various kinds per month and has handily weathered a number of major pipeline reconfigurations. The basic data model can be readily adapted to other high-volume processing environments.</p

Individual Attachment Style Modulates Human Amygdala and Striatum Activation during Social Appraisal

Adult attachment style refers to individual personality traits that strongly influence emotional bonds and reactions to social partners. Behavioral research has shown that adult attachment style reflects profound differences in sensitivity to social signals of support or conflict, but the neural substrates underlying such differences remain unsettled. Using functional magnetic resonance imaging (fMRI), we examined how the three classic prototypes of attachment style (secure, avoidant, anxious) modulate brain responses to facial expressions conveying either positive or negative feedback about task performance (either supportive or hostile) in a social game context. Activation of striatum and ventral tegmental area was enhanced to positive feedback signaled by a smiling face, but this was reduced in participants with avoidant attachment, indicating relative impassiveness to social reward. Conversely, a left amygdala response was evoked by angry faces associated with negative feedback, and correlated positively with anxious attachment, suggesting an increased sensitivity to social punishment. Secure attachment showed mirror effects in striatum and amygdala, but no other specific correlate. These results reveal a critical role for brain systems implicated in reward and threat processing in the biological underpinnings of adult attachment style, and provide new support to psychological models that have postulated two separate affective dimensions to explain these individual differences, centered on the ventral striatum and amygdala circuits, respectively. These findings also demonstrate that brain responses to face expressions are not driven by facial features alone but determined by the personal significance of expressions in current social context. By linking fundamental psychosocial dimensions of adult attachment with brain function, our results do not only corroborate their biological bases but also help understand their impact on behavior

Aqueous batteries as grid scale energy storage solutions

Energy storage technologies are required to make full use of renewable energy sources, and electrochemical cells offer a great deal flexibility in the design of energy systems. For large scale electrochemical storage to be viable, the materials employed and device production methods need to be low cost, devices should be long lasting and safety during operation is of utmost importance. Energy and power densities are of lesser concern. For these reasons, battery chemistries that make use of aqueous electrolytes are favorable candidates where large quantities of energy need to be stored. Herein we describe several different aqueous based battery chemistries and identify some of the research challenges currently hindering their wider adoption. Lead acid batteries represent a mature technology that currently dominates the battery market, however there remain challenges that may prevent their future use at the large scale. Nickel–iron batteries have received a resurgence of interest of late and are known for their long cycle lives and robust nature however improvements in efficiency are needed in order to make them competitive. Other technologies that use aqueous electrolytes and have the potential to be useful in future large-scale applications are briefly introduced. Recent investigations in to the design of nickel–iron cells are reported with it being shown that electrolyte decomposition can be virtually eliminated by employing relatively large concentrations of iron sulfide in the electrode mixture, however this is at the expense of capacity and cycle life

Neurobehavioral Mechanisms of Temporal Processing Deficits in Parkinson's Disease

Parkinson's disease (PD) disrupts temporal processing, but the neuronal sources of deficits and their response to dopamine (DA) therapy are not understood. Though the striatum and DA transmission are thought to be essential for timekeeping, potential working memory (WM) and executive problems could also disrupt timing.The present study addressed these issues by testing controls and PD volunteers 'on' and 'off' DA therapy as they underwent fMRI while performing a time-perception task. To distinguish systems associated with abnormalities in temporal and non-temporal processes, we separated brain activity during encoding and decision-making phases of a trial. Whereas both phases involved timekeeping, the encoding and decision phases emphasized WM and executive processes, respectively. The methods enabled exploration of both the amplitude and temporal dynamics of neural activity. First, we found that time-perception deficits were associated with striatal, cortical, and cerebellar dysfunction. Unlike studies of timed movement, our results could not be attributed to traditional roles of the striatum and cerebellum in movement. Second, for the first time we identified temporal and non-temporal sources of impaired time perception. Striatal dysfunction was found during both phases consistent with its role in timekeeping. Activation was also abnormal in a WM network (middle-frontal and parietal cortex, lateral cerebellum) during encoding and a network that modulates executive and memory functions (parahippocampus, posterior cingulate) during decision making. Third, hypoactivation typified neuronal dysfunction in PD, but was sometimes characterized by abnormal temporal dynamics (e.g., lagged, prolonged) that were not due to longer response times. Finally, DA therapy did not alleviate timing deficits.Our findings indicate that impaired timing in PD arises from nigrostriatal and mesocortical dysfunction in systems that mediate temporal and non-temporal control-processes. However, time perception impairments were not improved by DA treatment, likely due to inadequate restoration of neuronal activity and perhaps corticostriatal effective-connectivity