69 resultados para Refined earthenware


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The molecular structure of trans-[PtCl(CHCH2)(PEt2Ph)2] has been determined by X-ray diffraction methods. The crystals are orthorhombic, space group Pbcn, with a= 10.686(2), b= 13.832(4), c= 16.129(4)Å, and Z= 4. The structure has been solved by the heavy-atom method and refined by full-matrix least squares to R 0.044 for 1 420 diffractometric intensity data. The crystals contain discrete molecules in which the platinum co-ordination is square planar. The Pt–Cl bond vector coincides with a crystallographic diad axis about which the atoms of the vinyl group are disordered. Selected bond lengths (Å) are Pt–Cl 2.398(4), Pt–P 2.295(3), and Pt–C 2.03(2). The Pt–CC angle is 127(2)°. From a survey of the available structural data it is concluded that there is little, if any, back donation from platinum to carbon in platinum–alkenyl linkages.

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In 2007, the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) was operated for a nine-month period in the Murg Valley, Black Forest, Germany, in support of the Convective and Orographically-induced Precipitation Study (COPS). The synergy of AMF and COPS partner instrumentation was exploited to derive a set of high-quality thermodynamic and cloud property profiles with 30 s resolution. In total, clouds were present 72% of the time, with multi-layer mixed phase (28.4%) and single-layer water clouds (11.3%) occurring most frequently. A comparison with the Cloudnet sites Chilbolton and Lindenberg for the same time period revealed that the Murg Valley exhibits lower liquid water paths (LWPs; median = 37.5 g m−2) compared to the two sites located in flat terrain. In order to evaluate the derived thermodynamic and cloud property profiles, a radiative closure study was performed with independent surface radiation measurements. In clear sky, average differences between calculated and observed surface fluxes are less than 2% and 4% for the short wave and long wave part, respectively. In cloudy situations, differences between simulated and observed fluxes, particularly in the short wave part, are much larger, but most of these can be related to broken cloud situations. The daytime cloud radiative effect (CRE), i.e. the difference of cloudy and clear-sky net fluxes, has been analysed for the whole nine-month period. For overcast, single-layer water clouds, sensitivity studies revealed that the CRE uncertainty is likewise determined by uncertainties in liquid water content and effective radius. For low LWP clouds, CRE uncertainty is dominated by LWP uncertainty; therefore refined retrievals, such as using infrared and/or higher microwave frequencies, are needed.

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In this paper, the statistical properties of tropical ice clouds (ice water content, visible extinction, effective radius, and total number concentration) derived from 3 yr of ground-based radar–lidar retrievals from the U.S. Department of Energy Atmospheric Radiation Measurement Climate Research Facility in Darwin, Australia, are compared with the same properties derived using the official CloudSat microphysical retrieval methods and from a simpler statistical method using radar reflectivity and air temperature. It is shown that the two official CloudSat microphysical products (2B-CWC-RO and 2B-CWC-RVOD) are statistically virtually identical. The comparison with the ground-based radar–lidar retrievals shows that all satellite methods produce ice water contents and extinctions in a much narrower range than the ground-based method and overestimate the mean vertical profiles of microphysical parameters below 10-km height by over a factor of 2. Better agreements are obtained above 10-km height. Ways to improve these estimates are suggested in this study. Effective radii retrievals from the standard CloudSat algorithms are characterized by a large positive bias of 8–12 μm. A sensitivity test shows that in response to such a bias the cloud longwave forcing is increased from 44.6 to 46.9 W m−2 (implying an error of about 5%), whereas the negative cloud shortwave forcing is increased from −81.6 to −82.8 W m−2. Further analysis reveals that these modest effects (although not insignificant) can be much larger for optically thick clouds. The statistical method using CloudSat reflectivities and air temperature was found to produce inaccurate mean vertical profiles and probability distribution functions of effective radius. This study also shows that the retrieval of the total number concentration needs to be improved in the official CloudSat microphysical methods prior to a quantitative use for the characterization of tropical ice clouds. Finally, the statistical relationship used to produce ice water content from extinction and air temperature obtained by the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite is evaluated for tropical ice clouds. It is suggested that the CALIPSO ice water content retrieval is robust for tropical ice clouds, but that the temperature dependence of the statistical relationship used should be slightly refined to better reproduce the radar–lidar retrievals.

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We have carried out a thorough mineralogical analysis of 16 pottery samples from the Lapita site of Bourwera in Fiji, using micromorphological techniques with optical and polarising microscopes. While the overall mineralogy of all of the samples is similar the samples clearly divide into two groups, namely those with or without the mineral calcite. Our findings are backed up by chemical analysis using SEM–EDX and FTIR. SEM–EDX shows the clear presence of inclusions of calcite in some of the samples; FTIR shows bands arising from calcite in these samples. The study suggests that it is likely that more than one clay source was used for production of this pottery, but that most of the pottery comes from a single source. This finding is in line with previous studies which suggest some trading of pottery between the Fijian islands but a single source of clay for most of the pottery found at Bouwera. We found no evidence for the destruction of CaCO3 by heating upon production of the pottery in line with the known technology of the Lapita people who produced earthenware pottery but not high temperature ceramics.

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The phenolic fractions released during hydrothermal treatment of selected feedstocks (corn cobs, eucalypt wood chips, almond shells, chestnut burs, and white grape pomace) were selectively recovered by extraction with ethyl acetate and washed with ethanol/water solutions. The crude extracts were purified by a relatively simple adsorption technique using a commercial polymeric, nonionic resin. Utilization of 96% ethanol as eluting agent resulted in 47.0-72.6% phenolic desorption, yielding refined products containing 49-60% w/w phenolics (corresponding to 30-58% enrichment with respect to the crude extracts). The refined extracts produced from grape pomace and from chestnut burs were suitable for protecting bulk oil and oil-in-water and water-in-oil emulsions. A synergistic action with bovine serum albumin in the emulsions was observed.

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Common approaches to the simulation of borehole heat exchangers (BHEs) assume heat transfer in circulating fluid and grout to be in a quasi-steady state and ignore fluctuations in fluid temperature due to transport of the fluid around the loop. However, in domestic ground source heat pump (GSHP) systems, the heat pump and circulating pumps switch on and off during a given hour; therefore, the effect of the thermal mass of the circulating fluid and the dynamics of fluid transport through the loop has important implications for system design. This may also be important in commercial systems that are used intermittently. This article presents transient simulation of a domestic GSHP system with a single BHE using a dynamic three-dimensional (3D) numerical BHE model. The results show that delayed response associated with the transit of fluid along the pipe loop is of some significance in moderating swings in temperature during heat pump operation. In addition, when 3D effects are considered, a lower heat transfer rate is predicted during steady operations. These effects could be important when considering heat exchanger design and system control. The results will be used to develop refined two-dimensional models.

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Barium ferrites substituted by Mn–Sn, Co–Sn, and Mn–Co–Sn with general formulae BaFe12−2xMnxSnxO19 (x=0.2–1.0), BaFe12−2xCoxSnxO19 (x=0.2–0.8), and BaFe12−2xCox/2Mnx/2SnxO19 (x=0.1–0.6), respectively, have been prepared by a previously reported co-precipitation method. The efficiency of the method was refined by lowering the reaction temperature and shortening the required reaction time, due to which crystallinity improved and the value of saturated magnetization increased as well. Low coercivity temperature coefficients, which are adjustable by doping, were achieved by Mn–Sn and Mn–Co–Sn doping. Synthesis efficiency and the effect of doping are discussed taking into account accumulated data concerning the synthesis and crystal structure of ferrites.

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In the European Union, first-tier assessment of the long-term risk to birds and mammals from pesticides is based on calculation of a deterministic long-term toxicity/exposure ratio(TERlt). The ratio is developed from generic herbivores and insectivores and applied to all species. This paper describes two case studies that implement proposed improvements to the way long-term risk is assessed. These refined methods require calculation of a TER for each of five identified phases of reproduction (phase-specific TERs) and use of adjusted No Observed Effect Levels (NOELs)to incorporate variation in species sensitivity to pesticides. They also involve progressive refinement of the exposure estimate so that it applies to particular species, rather than generic indicators, and relates spraying date to onset of reproduction. The effect of using these new methods on the assessment of risk is described. Each refinement did not necessarily alter the calculated TER value in a way that was either predictable or consistent across both case studies. However, use of adjusted NOELs always reduced TERs, and relating spraying date to onset of reproduction increased most phase-specific TERs. The case studies suggested that the current first-tier TERlt assessment may underestimate risk in some circumstances and that phase-specific assessments can help identify appropriate risk-reduction measures. The way in which deterministic phase-specific assessments can currently be implemented to enhance first-tier assessment is outlined.

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The Cognitive Development Questionnaire (CDQ) allows accurate assessment of cognitive development of children from 10 to 24 months by parents and caregivers in the home. It takes between one and two hours to complete over about a week. Three phases of work are described, in which the instrument is progressively refined to improve its validity and reliability. This resulting version of the CDQ shows excellent correlation with age, and with the Mental Scale of the Bayley Scales of Infant Development (Bayley, 1993). The CDQ thus offers researchers and clinicians a useful alternative to professionally-administered cognitive assessment in infancy.

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The United Kingdom’s pharmacy regulator contemplated using continuing professional development (CPD) in pharmacy revalidation in 2009, simultaneously asking pharmacy professionals to demonstrate the value of their CPD by showing its relevance and impact. The idea of linking new CPD requirements with revalidation was yet to be explored. Our aim was to develop and validate a framework to guide pharmacy professionals to select CPD activities that are relevant to their work and to produce a score sheet that would make it possible to quantify the impact and relevance of CPD. METHODS: We adapted an existing risk matrix, producing a CPD framework consisting of relevance and impact matrices. Concepts underpinning the framework were refined through feedback from five pharmacist teacher-practitioners. We then asked seven pharmacists to rate the relevance of the framework’s individual elements on a 4-point scale to determine content validity. We explored views about the framework through focus groups with six and interviews with 17 participants who had used it formally in a study. RESULTS: The framework’s content validity index was 0.91. Feedback about the framework related to three themes of penetrability of the framework, usefulness to completion of CPD, and advancement of CPD records for the purpose of revalidation. DISCUSSION: The framework can help professionals better select CPD activities prospectively, and makes assessment of CPD more objective by allowing quantification, which could be helpful for revalidation. We believe the framework could potentially help other health professionals with better management of their CPD irrespective of their field of practice.

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The mirror neuron system is widely held to provide direct access to the motor goals of others. This paper critically investigates this idea, focusing on the so-called ‘intentional worry’. I explore two answers to the intentional worry: first that the worry is premised on too limited an understanding of mirror neuron behaviour (Sections 2 and 3), second that the appeal made to mirror neurons can be refined in such a way as to avoid the worry (Section 4). I argue that the first response requires an account of the mechanism by which small-scale gestures are supposedly mapped to larger chains of actions but that none of the extant accounts of this mechanism are plausible. Section 4 then briefly examines refinements of the mirror neuron-mindreading hypothesis which avoid the intentional worry. I conclude that these refinements may well be plausible but that they undermine many of the claims standardly made for mirror neurons.

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In response to evidence of insect pollinator declines, organisations in many sectors, including the food and farming industry, are investing in pollinator conservation. They are keen to ensure that their efforts use the best available science. We convened a group of 32 ‘conservation practitioners’ with an active interest in pollinators and 16 insect pollinator scientists. The conservation practitioners include representatives from UK industry (including retail), environmental non-government organisations and nature conservation agencies. We collaboratively developed a long list of 246 knowledge needs relating to conservation of wild insect pollinators in the UK. We refined and selected the most important knowledge needs, through a three-stage process of voting and scoring, including discussions of each need at a workshop. We present the top 35 knowledge needs as scored by conservation practitioners or scientists. We find general agreement in priorities identified by these two groups. The priority knowledge needs will structure ongoing work to make science accessible to practitioners, and help to guide future science policy and funding. Understanding the economic benefits of crop pollination, basic pollinator ecology and impacts of pesticides on wild pollinators emerge strongly as priorities, as well as a need to monitor floral resources in the landscape.

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'The Prophetic Sound: a day and night of noise cabaret' is the first event hosted by Agency of Noise. This all day event brought together artists and academics whose subject of focus is noise (in creative practice). Artists from across the UK were invited to consider a future post-digital era in which everything with a microchip has malfunctioned, as a thought exercise and starting point for response through sound. In response to Jacques Attali’s claim that music is prophecy, The Prophetic Sound asks us to consider if noise can communicate in an unbridled, unfiltered, way that is somehow not culturally coded -before it becomes sound that is recognised, refined, manipulated and exploited for musical or other cultured purpose. Featuring students from Reading, Brighton, LCC and Goldsmiths alongside more established artists and academics from across the UK, this event brings into focus locations where pattern, timbre, pitch, organisation and sequencing of sounds become distinguishable from noise and asks us to consider, through diversion within such locations, new origins for future communication systems. The Prophetic Sound included talks, films, presentations and performances from: Ryo Ikeshiro / Inigo Wilkins / Neal Spowage / Dane Sutherland / Poulomi Desai / Benedict Drew / AAS / Polly Fibre / Steven Dickie As part of The Prophetic Sound, POLLYFIBRE (Ellison, C.) performed LIVE RECORDING with Amplified Scissors. This industrial activity by POLLYFIBRE short-circuits the complicated chain that is music production. The distinctive roles of consumer, producer, composer, and performer collapse in a series of live ‘cuts’ where vinyl discs are produced with amplified scissors. Production happens through action and action becomes production. A limited edition of 9 flexi discs were produced and available for special collectors at the event.

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The ECMWF operational grid point model (with a resolution of 1.875° of latitude and longitude) and its limited area version (with a resolution of !0.47° of latitude and longitude) with boundary values from the global model have been used to study the simulation of the typhoon Tip. The fine-mesh model was capable of simulating the main structural features of the typhoon and predicting a fall in central pressure of 60 mb in 3 days. The structure of the forecast typhoon, with a warm core (maximum potential temperature anomaly 17 K). intense swirling wind (maximum 55 m s-1 at 850 mb) and spiralling precipitation patterns is characteristic of a tropical cyclone. Comparison with the lower resolution forecast shows that the horizontal resolution is a determining factor in predicting not only the structure and intensity but even the movement of these vortices. However, an accurate and refined initial analysis is considered to be a prerequisite for a correct forecast of this phenomenon.

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Introduction. Feature usage is a pre-requisite to realising the benefits of investments in feature rich systems. We propose that conceptualising the dependent variable 'system use' as 'level of use' and specifying it as a formative construct has greater value for measuring the post-adoption use of feature rich systems. We then validate the content of the construct as a first step in developing a research instrument to measure it. The context of our study is the post-adoption use of electronic medical records (EMR) by primary care physicians. Method. Initially, a literature review of the empirical context defines the scope based on prior studies. Having identified core features from the literature, they are further refined with the help of experts in a consensus seeking process that follows the Delphi technique. Results.The methodology was successfully applied to EMRs, which were selected as an example of feature rich systems. A review of EMR usage and regulatory standards provided the feature input for the first round of the Delphi process. A panel of experts then reached consensus after four rounds, identifying ten task-based features that would be indicators of level of use. Conclusions. To study why some users deploy more advanced features than others, theories of post-adoption require a rich formative dependent variable that measures level of use. We have demonstrated that a context sensitive literature review followed by refinement through a consensus seeking process is a suitable methodology to validate the content of this dependent variable. This is the first step of instrument development prior to statistical confirmation with a larger sample.