984 resultados para local thermodynamic equilibrium


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Designers have a social responsibility to deal with the needs, issues, and problems that their clients and communities are confronted with. Students of design require opportunities to reflect on their role as social facilitators to develop an attitude towards community engagement through different phases and aspects of their careers. However, current design courses are challenged by compressed timeframes and fragmented scenarios of different academic requirements that do not actively teach community engagement. This paper outlines a participatory and technological approach that was employed to address these issues within the teaching of Architecture and Urban Design at the Queensland University of Technology, Brisbane, Australia. A multi-phase community based research project with actual stakeholders was implemented over a two-year period. Approximately 150 students in the final year of the Bachelor of Design-Architecture; 10 students in the Master of Architecture and 15 students in the Master of Design-Urban Design have informed and influenced each others’ learning through the teaching and research nexus facilitated by this project. The technical approach was implemented in form of a bespoke digital platform that supported the display and discussion of digital media on a series of interactive touch walls. The platform allowed students to easily upload their final designs onto large interactive surfaces, where visitors could explore the media and provide comments. Through the use of this technical platform and the introduction of neogeography, students have been able to broaden their level of interaction and support their learning experience through external structured and unstructured feedback from the local community. Students have not only been exposed to community representatives, but they also have been working in parallel on a specific case study providing each other, across different years and courses, material for reflection and data to structure their design activities.

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Uncertainty assessments of herbicide losses from rice paddies in Japan associated with local meteorological conditions and water management practices were performed using a pesticide fate and transport model, PCPF-1, under the Monte Carlo (MC) simulation scheme. First, MC simulations were conducted for five different cities with a prescribed water management scenario and a 10-year meteorological dataset of each city. The effectiveness of water management was observed regarding the reduction of pesticide runoff. However, a greater potential of pesticide runoff remained in Western Japan. Secondly, an extended analysis was attempted to evaluate the effects of local water management and meteorological conditions between the Chikugo River basin and the Sakura River basin using uncertainty inputs processed from observed water management data. The results showed that because of more severe rainfall events, significant pesticide runoff occurred in the Chikugo River basin even when appropriate irrigation practices were implemented. © Pesticide Science Society of Japan.

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Educating responsive graduates. Graduate competencies include reliability, communication skills and ability to work in teams. Students using Collaborative technologies adapt to a new working environment, working in teams and using collaborative technologies for learning. Collaborative Technologies were used not simply for delivery of learning but innovatively to supplement and enrich research-based learning, providing a space for active engagement and interaction with resources and team. This promotes the development of responsive ‘intellectual producers’, able to effectively communicate, collaborate and negotiate in complex work environments. Exploiting technologies. Students use ‘new’ technologies to work collaboratively, allowing them to experience the reality of distributed workplaces incorporating both flexibility and ‘real’ time responsiveness. Students are responsible and accountable for individual and group work contributions in a highly transparent and readily accessible workspace. This experience provides a model of an effective learning tool. Navigating uncertainty and complexity. Collaborative technologies allows students to develop critical thinking and reflective skills as they develop a group product. In this forum students build resilience by taking ownership and managing group work, and navigating the uncertainties and complexities of group dynamics as they constructively and professionally engage in team dialogue and learn to focus on the goal of the team task.

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In some of the countries where there has been a rapid increase in the use of online music distribution technologies, analysts have reported about declining sales of local music repertoire (e.g. Nordgård, 2013). The analysts are concerned about such tendencies since local music repertoire accounts for a sizable share of an average country’s total recorded music sales (e.g. IFPI, 2012). This paper searches for empirical evidence that may confirm these reports in a number of music markets in North America, Europe and Australasia. The paper makes a contribution to the literature on the digital transformation of the music industry since it combines and analyses data sources that previously have not been used in this context and gives a new perspective on changing user consumption practices in the music industry. The paper also examines the variation of geographic diversity over time among international acts that become commercially successful in the countries covered by the study.

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The conformational stability of the homodimeric pea lectin was determined by both isothermal urea-induced and thermal denaturation in the absence and presence of urea. The denaturation profiles were analyzed to obtain the thermodynamic parameters associated with the unfolding of the protein. The data not only conform to the simple A(2) double left right arrow 2U model of unfolding but also are well described by the linear extrapolation model for the nature of denaturant-protein interactions. In addition, both the conformational stability (Delta G(s)) and the Delta C-p for the protein unfolding is quite high, at about 18.79 kcal/ mol and 5.32 kcal/(mol K), respectively, which may be a reflection of the relatively larger size of the dimeric molecule (M-r 49 000) and, perhaps, a consequent larger buried hydrophobic core in the folded protein. The simple two-state (A(2) double left right arrow 2U) nature of the unfolding process, with the absence of any monomeric intermediate, suggests that the quaternary interactions alone may contribute significantly to the conformational stability of the oligomer-a point that may be general to many oligomeric proteins.

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The binding of xylo-oligosaccharides to Chainia endoxylanase resulted in a decrease in fluorescence intensity of the enzyme with the formation of 1:1 complex. Equilibrium and thermodynamic parameters of ligand binding were determined by fluorescence titrations and titration calorimetry. The affinity of xylanase for the oligosaccharides increases in the order X-2 < X-3 < X-4 less than or equal to X-5. Contributions from the enthalpy towards the free energy change decreased with increasing chain length from X-2 to X-4, whereas an increase in entropy was observed, the change in enthalpy and entropy of binding being compensatory. The entropically driven binding process suggested that hydrophobic interactions as well as hydrogen bonds play a predominant role in ligand binding.

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We report the direct observation of electrochemical potential and local transport field variations near scatterers like grain boundaries, triple points, and voids in thin platinum films studied by scanning tunneling potentiometry. The field is highest at a void, followed by a triple point and a grain boundary. The local transport field near a void can even be four orders of magnitude higher than the macroscopic field, indicating that the void is the most likely place for an electromigration induced failure. The field build up for a particular type of scatterer depends on the grain connectivity. We estimate an average grain boundary reflection coefficient for the film from the temperature dependence of its resistivity.

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Sob o rótulo da globalização, as ciências humanas e sociais têm sido forçadas a rever seu pensamento para encontrar novas maneiras de falar sobre as situações de mudança ao nosso redor e para reorientar-se conceitualmente em um aparente ‘mundo sem fronteiras’. Este artigo analisa algumas dessas formas, sugerindo que a pesquisa em currículo transnacional como tarefa, como talvez inclusiva de algo para além dos estudos curriculares como subárea, tem preocupações, pontos de entrada e horizontes de promulgação amplos, inconstantes, imprevisíveis, que levantam uma série de questões e considerações éticas que exigem maior compromisso nos espaços em que as fronteiras percebidas forem transgredidas no ato da investigação. Usando os relatórios sobre os resultados do PISA como disparador intelectual, este artigo discute quatro questões que surgem no ato investigativo em currículo transnacional: a comparação como princípio de produção de conhecimento; as estratégias de agrupamento onto-teo-filosóficas e a delimitação da ética; o retorno do sujeito centrado, humanista, racional e as críticas a esse sujeito inspirado no Iluminismo; as questões relativas à causalidade, ou seja, como os processos de atribuição são forjados e que tipos de ‘legitimação via procedimento’ operam na crítica social. Em vez de sugerir uma nova ordem, este artigo busca um questionamento mais profundo dos repetitivos pressupostos ocidentalistas.

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The equilibrium geometry, electronic structure and energetic stability of Bi nanolines on clean and hydrogenated Si(001) surfaces have been examined by means of ab initio total energy calculations and scanning tunnelling microscopy. For the Bi nanolines on a clean Si surface the two most plausible structural models, the Miki or M model (Miki et al 1999 Phys. Rev. B 59 14868) and the Haiku or H model (Owen et al 2002 Phys. Rev. Lett. 88 226104), have been examined in detail. The results of the total energy calculations support the stability of the H model over the M model, in agreement with previous theoretical results. For Bi nanolines on the hydrogenated Si(001) surface, we find that an atomic configuration derived from the H model is also more stable than an atomic configuration derived from the M model. However, the energetically less stable (M) model exhibits better agreement with experimental measurements for equilibrium geometry. The electronic structures of the H and M models are very similar. Both models exhibit a semiconducting character, with the highest occupied Bi-derived bands lying at ~0.5 eV below the valence band maximum. Simulated and experimental STM images confirm that at a low negative bias the Bi lines exhibit an 'antiwire' property for both structural models.

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The scanning tunneling microscope (STM) has evolved continually since its invention, as scientists have expanded its use to encompass atomic-scale manipulation, momentum-resolved electronic characterization, localized chemical reactions (bond breaking and bond making) in adsorbed molecules, and even chain reactions at surfaces. This burgeoning field has recently expanded to include the use of the STM to inject hot electrons into substrate surface states; the injected electrons can travel laterally and induce changes in chemical structure in molecules located up to 100 nm from the STM tip. We describe several key demonstrations of this phenomenon, including one appearing in this issue of ACS Nano by Chen et al. Possible applications for this technique are also discussed, including characterizing the dispersion of molecule−substrate interface states and the controlled patterning of molecular overlayers.

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Nine tie-lines between Fe-Ni alloys and FeTiO3-NiTiO3 solid solutions were determined at 1273 K. Samples were equilibrated in evacuated quartz ampoules for periods up to 10 days. Compositions of the alloy and oxide phases at equilibrium were determined by energy-dispersive x-ray spectroscopy. X-ray powder diffraction was used to confirm the results. Attainment of equilibrium was verified by the conventional tie-line rotation technique and by thermodynamic analysis of the results. The tie-lines are skewed toward the FeTiO3 corner. From the tie-line data and activities in the Fe-Ni alloy phase available in the literature, activities of FeTiO3 and NiTiO3 in the ilmenite solid solution were derived using the modified Gibbs-Duhem technique of Jacob and Jeffes [K.T. Jacob and J.H.E. Jeffes, An Improved Method for Calculating Activities from Distribution Equilibria, High Temp. High Press., 1972, 4, p 177-182]. The components of the oxide solid solution exhibit moderate positive deviations from Raoult's law. Within experimental error, excess Gibbs energy of mixing for the FeTiO3-NiTiO3 solid solution at 1273 K is a symmetric function of composition and can be represented as: Delta G(E) = 8590 (+/- 200) X-FeTiO3 X-NiTiO3 J/mol Full spectrum of tie-lines and oxygen potentials for the three-phase equilibrium involving Fe-Ni alloys, FeTiO3-NiTiO3 solid solutions, and TiO2 at 1273 K were computed using results obtained in this study and data available in the literature.

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Recent calls in Australia have addressed the need for better integration of planning processes. The consequent effort made by government has been, and still is, reshaping the way urban and regional planning and sustainability are managed. Focusing on planning practices at the local and regional levels, we investigate how environmental sustainability is pursued from an institutional perspective. Specifically, we analyse the way that planning in Australian cities aims to achieve sustainable strategies and reflect on the relationship with ‘Strategic Environmental Assessment’. This paper has four goals. First, sustainable planning practices at the local and regional levels are analysed considering the legislative and organizational frameworks of each state. The goal is to identify through an analysis of planning documents how much discretion is given to local councils to address sustainable strategies. Second, we focus on two regional and four cities in Queensland, to outline strengths and weaknesses of current legislative and practical frameworks. We use analytical criteria from the SEA literature to investigate these plans in more detail. Third, we examine the relationship between strategic and statutory plans, to see how sustainability is actually implemented. Finally we compare emerging issues about sustainable planning in Australia with countries overseas with different planning and SEA traditions. Considering that SEA is evolving and there are considerable international experiences, we offer recommendations on how Australia might achieve a more integrated and sustainable approach to planning.

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We propose three variants of the extended Kalman filter (EKF) especially suited for parameter estimations in mechanical oscillators under Gaussian white noises. These filters are based on three versions of explicit and derivative-free local linearizations (DLL) of the non-linear drift terms in the governing stochastic differential equations (SDE-s). Besides a basic linearization of the non-linear drift functions via one-term replacements, linearizations using replacements through explicit Euler and Newmark expansions are also attempted in order to ensure higher closeness of true solutions with the linearized ones. Thus, unlike the conventional EKF, the proposed filters do not need computing derivatives (tangent matrices) at any stage. The measurements are synthetically generated by corrupting with noise the numerical solutions of the SDE-s through implicit versions of these linearizations. In order to demonstrate the effectiveness and accuracy of the proposed methods vis-à-vis the conventional EKF, numerical illustrations are provided for a few single degree-of-freedom (DOF) oscillators and a three-DOF shear frame with constant parameters.

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The standard free energies of formation of CaO derived from a variety of high-temperature equilibrium measurements made by seven groups of experimentalists are significantly different from those given in the standard compilations of thermodynamic data. Indirect support for the validity of the compiled data comes from new solid-state electrochemical measurements using single-crystal CaF2 and SrF2 as electrolytes. The change in free energy for the following reactions are obtained: CaO + MgF2 --> MgO + CaF2 Delta G degrees = -68,050 -2.47 T(+/-100) J mol(-1) SrO + CaF2 --> SrF2 + CaO Delta G degrees = -35,010 + 6.39 T (+/-80) J mol(-1) The standard free energy changes associated with cell reactions agree with data in standard compilations within +/- 4 kJ mol(-1). The results of this study do not support recent suggestions for a major revision in thermodynamic data for CaO.