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The performance of porous carbon materials as sorbents is often compromised by the presence of humidity. Studying the kinetics of water vapour adsorption on activated carbons will undeniably help to overcome this issue. This has been approached in this work by evaluating the influence of several operational factors on the dynamic adsorption of water vapour in these materials. Specifically, different carbon types, particle sizes, air flows and ambient conditions (temperature and relative humidity (RH)) were systematically investigated. The impact of each isolated parameter on both the maximum water uptake and the uptake rate was analyzed by fitting the experimental data to the Linear Driving Force (LDF) kinetic model. The results show that except for the particle size, the studied variables play a role in the water sorption kinetics, although to a different extent. It was also confirmed that the LDF model can adequately describe the kinetics of water vapour adsorption independently of the experimental conditions. Finally, the complete water vapour adsorption process can be described by this model, obtaining a different value of the kinetic constant for the sequential stages, involving different adsorption mechanisms.

It is very important to be able to predict the breakthrough time of gas mask filters under real life circumstances. This article describes the use of a very simple predictive equation, the Wheeler-Jonas equation, that yields excellent predictions but only within a very restrictive set of boundary conditions. In order to make this model work in a more realistic environment, it has been gradually adapted to take into account a number of parameters related to this environment: a non-constant inlet concentration, a breather flow, new physical forms of activated carbon, the relative humidity and temperature of the ambient air, chemisorbed gases and mixtures of organic vapours. As (nearly) all of these parameters can be calculated independently of each other, based on data that are either readily available or that can be measured, their influence on the complexity of the model stays low. This makes this combined model both easy to use and powerful in predicting breakthrough times of gas mask filters under real-life conditions.

The effect of temperature on the adsorption of lead by an activated carbon from coconut shells is investigated. The pseudo second order equation is applied to the kinetic data obtained at different temperatures in order to determine the adsorption rate constants at these temperatures. Then, the Arrhenius equation is applied to the rate constants to determine the activation energy of the sorption reaction and the pre-exponential factor. By applying the Eyring equation to the rate constants, the standard thermodynamic activation parameters of the sorption reaction can also be calculated. In addition, the isotherms of lead adsorption on the activated carbon from coconut shells, at different temperatures, are determined and fitted by the Langmuir equation. The Van’t Hoff equation is applied to the Langmuir equilibrium constants in order to determine the standard enthalpy of the sorption reaction. The other standard thermodynamic parameters (Gibbs standard enthalpy and standard entropy) are deduced. The isosteric standard sorption enthalpy is also determined by using both the classical approach and an adapted Clausius Clapeyron equation. The results are identical. The value obtained is higher, but more correct than that of Langmuir. On the basis of these thermokinetic parameters, the activated carbon from Coconut shells can be considered as a very efficient carbon for the sorption of lead and its sorption efficiency (rate and quantity) increase with the temperature.

An activated carbon from Bois carré (Citharexylum Fruticosum L.) seeds was prepared by chemical activation with phosphoric acid. The activated carbon obtained has a surface area of 594 m2/g and a high content of acid groups of 3.44 mmol.g-1. This carbon was studied for the removal of lead from water. Sorption studies were performed at 30 °C at different pH and adsorbent doses, in batch mode. Maximum adsorption occurred at pH 7 for an adsorbent dose of 1g/L. Kinetic studies, at the initial concentration of 150 mg/L of lead, pH 5 and an adsorbent dose of 1 g/L, yielded an equilibrium time of 30 h for this activated carbon. The kinetic data were modelled with the pseudo first order, the pseudo second order and the Bangham models. The pseudo second order model fitted the data well. The sorption rate constant (2.10-3 mol-1.Kg.s-1) and the maximum amount of lead adsorbed are quite good (0.18 mol.kg-1) compared to the data found in literature. Sorption equilibrium studies were conducted in a concentration range of lead from 0 to 150 mg/L, at pH 5, adsorbent dose 1 g/L. In an aqueous lead solution with an initial concentration of 30 mg/L, activated Bois carré seed carbon removed (at equilibrium) 48 % of the heavy metal. The equilibrium data were modelled with the Langmuir and Freundlich equations, of which the latter gave the best fit. The Freundlich constants n (3.76 L.mol-1) and Kf (1.06 mol.kg-1) are in good agreement with literature. The Bois carré seed activated carbon is a very efficient carbon in terms of the metal amount adsorbed per unit of surface area (0. 06 m2 /g). This good result is due to the presence of many active acid sites on the surface of this activated carbon.

Abstract Aims Heart failure in adults is characterized by reduction of long‐chain fatty acid oxidation in favour of carbohydrate metabolism. This adaptive phenomenon becomes maladaptive because energy conversion decreases and lipid toxic derivatives known to impair cardiac function are accumulating. No data are available concerning metabolic modification in heart failure in children. Methods and results In order to evaluate the fatty acid oxidation in children suffering from heart failure, acylcarnitine profiles on dried blood spots were obtained from children under 16 years old with dilated cardiomyopathy and clinical heart failure (DCM‐HF) and control children. Nine children were included in the DCM‐HF group and eight in the control group. Acylcarnitine profiles revealed a significant 3.1‐fold increase of total acylcarnitines (sum of C3 to C18 acylcarnitine species) in DCM‐HF children compared with controls. This result persisted considering the sum of long‐chain acylcarnitines (sum of C14 to C18 species), medium‐chain acylcarnitines (sum of C8 to C12 species), and short‐chain acylcarnitines (sum of C3 to C6 species), respectively, 2.0‐, 2.6‐, and 1.9‐fold increase compared with the control group. A significant linear correlation was found between left ventricular dilatation or ejection fraction and acylcarnitines accumulation. Finally, acylcarnitine ratio C16OH/C16 and C18OH/C18 enhanced in the DCM‐HF group, suggesting a diminution of the long‐chain hydroxyl acyl‐CoA dehydrogenase activity. Conclusions Our results suggest down‐regulation of fatty acid oxidation in children with heart failure. Such lipidomic alteration could worsen heart function and may suggest considering a metabolic treatment of heart failure in children.

Purpose: This study provides a country-specific and sector-wide study of campus sustainability. Campus sustainability is a key consideration for the higher education (HEI) sector, and campus sustainability officers and managers manage its reporting and planning. Global and country-specific studies to date have focussed on individual organisation narratives, interviews with faculty and management and content analysis of reports and plans. Findings show wide divergence on scope and scale of formalised planning and reporting, few references to sustainability officers and managers' perspectives and limited reference to organisational theory to explain tactics and strategies adopted. As a result, there are a few country-specific and sector-wide studies. The purpose of this paper is to address the scarcity of country-specific and sector-wide studies into campus sustainability practices in HEI by combining qualitative and quantitative analysis. Design/methodology/approach: The authors provide the first sector-wide overview of formal campus sustainability commitments for the Australian public sector HEI (n = 41) in terms of several key indicators -- plans, reports and other indicators. Second, the authors use reflexive thematic analysis of interviews (n = 21) with current and former sustainability officers and managers to examine sector organisational reasons for such variation. Third, the authors analyse HEI sector isomorphism and divergence on planning and reporting of campus sustainability from the perspective of institutional theory of organisations. Findings: This study finds some convergence on the need for plans, reporting and other engagement elements, albeit without any sector-wide standards being followed. The authors observe a trend towards carbon-neutral (CN) declarations before 2030 although with nuances on emissions scope and increasing inclusion of renewable energy. Interviews identify a range of strategies and tactics adopted for campus sustainability relative to internal and external organisational pressures. Overall, the sector still exhibits weak institutionalisation of sustainability. Research limitations/implications: This study interviews a specific and limited cohort (n = 21) and presents an overview of sector reporting, planning and target setting although not a detailed content analysis. Other interview cohorts may have different views on the strategic and tactical purposes of reporting practices, and more in-depth analysis of formal plans and reports should be conducted in the future. Practical implications: This study concludes that the Australian HEI sector should consider greater public transparency of its data and reporting actions. Common standards and a benchmarking platform for the sector would improve overall engagement with all internal and external stakeholders. At present, the HEI sector's message to its key internal and external stakeholders is mixed and needs to change towards a more in-depth institutionalisation of sustainability on campus. Originality/value: Particular insights are the value of organisational strategies and tactics as an interpretive framework for HEI campus sustainability and how interviewees attribute sector competitors and self-different motives and tactics. Albeit limited, this is the first mapping of sector approaches to sustainability reporting and planning.

This study describes how a multidisciplinary team at an Australian university’s innovation hub developed their research targets and capacity. The process through which research teams establish their research targets and strategies for achieving them is often tacit, which makes process sharing challenging. Referencing Situated Learning Theory (Brown et al., 1989) and using the Design and Development Research (DDR) framework (Richey and Klein, 2007) we document the process of how researchers negotiate to develop team research targets in this study. Our workshop data suggests that if researchers want to leverage the research abilities of others in their team, their targets must remain flexible. Additionally, a range of individual and organisation hinderers, barriers and enablers of conducting research were identified, that can inform practical actions to realise research strategy targets for innovation hubs.

The characterization of fluorinated carbon fibers by water sorption has been broadly investigated in this work. In brief, a pitch-based activated carbon fiber (ACF) was submitted to a fluorination process under different conditions of partial pressure (F2:N2 ratio) and temperature. This led to samples with varied fluorine content and C-F type bonding. The effect of the fluorination treatment on the textural properties of the ACF was studied by means of nitrogen and carbon dioxide adsorption at −196 and 0°C, respectively, while the changes induced in the surface chemistry of the materials were analyzed by XPS. Also, the affinity and stability of the materials toward water was evaluated by single and cycling isotherms. The obtained results show that a mild fluorination not only can preserve most of the textural properties of the parent ACF, but enhance the water uptake at the first stages of the water sorption process, together with a shift in the upswing of the water isotherms toward lower relative humidities. This indicates that fluorination under certain conditions can actually enhance the surface hydrophilicity of carbon materials with specific properties. On the contrary, higher partial pressures led to highly fluorinated fibers with lower porosity and more hydrophobic character. Moreover, they presented a lower chemical stability as demonstrated by a change in the shape of the water isotherms after two consecutive measurements. The kinetics of water sorption in the ACFs provided further insights into the different sorption phenomena involved. Hence, water sorption can definitely help to tailor the water affinity, stability and performance of fluorinated porous carbon materials under humid conditions.

In the field of cognitive psychology, the "p"-value hypothesis test has established a stranglehold on statistical reporting. This is unfortunate, as the "p"-value provides at best a rough estimate of the evidence that the data provide for the presence of an experimental effect. An alternative and arguably more appropriate measure of evidence is conveyed by a Bayesian hypothesis test, which prefers the model with the highest average likelihood. One of the main problems with this Bayesian hypothesis test, however, is that it often requires relatively sophisticated numerical methods for its computation. Here we draw attention to the "Savage-Dickey density ratio" method, a method that can be used to compute the result of a Bayesian hypothesis test for nested models and under certain plausible restrictions on the parameter priors. Practical examples demonstrate the method's validity, generality, and flexibility. (Contains 12 figures.)

An invitational teaching ecosystem comprises an environment of 5 Ps: people, places, policies, programmes and processes. Invitational education is promoted amongst students and educators. This article reports on an empirical study conducted at a higher education institution that is offering programmes at multiple sites of delivery to determine the impact of mergers on an invitational ecosystem. Results indicate that access to learning resources that support teaching, as well as other social and personal factors in the learning environment, also inluence the quality of a student's learning. Enthusiasm, motivation and sensitivity of educators are noted by students as necessary to create an invitational ecosystem. Key priority areas on which higher education institutions should focus are highlighted in the indings. A qualitative approach was followed to understand and represent the opinions of the students at the different sites of delivery. This article attempts to represent the views of students on the balance between people, places, policies, programmes and processes within the educational transaction movements. (Contains 4 tables, 3 figures, and 1 note.)

The article offers information on a colloquium organized by the Dutch-Flemish Society for Music Theory in the Hague, Netherland which tackles the approaches in music education and performance.

In recent years, partimento has rapidly become an important tool in the pedagogy of music theory and in performance practice. In this survey, eight European partimentisti (Nicholas Baragwanath, Nicola Cumer, Therese de Goede, Ewald Demeyere, Jorge Garcia, Birger Petersen, Giorgio Sanguinetti, and Peter van Tour) answer eight questions, outlining their diverse uses of partimento in the classroom. [ABSTRACT FROM AUTHOR]

Abstract: The effect of temperature on the adsorption of lead by an activated carbon from Bois carré seeds is investigated. The pseudo second order equation is applied to the kinetic data obtained at different temperatures in order to determine the adsorption rate constants at these temperatures. Then, the Arrhenius equation is applied to these rate constants to determine the activation energy of the sorption reaction and the pre-exponential factor. They are equal to 37kJmol−1 and 6.1×103 mol−1 kgs−1, respectively. By applying the Eyring equation to the rate constants, the standard thermodynamic activation parameters of the sorption reaction can also be calculated. In addition, the isotherms of lead adsorption on the activated carbon from Bois carré seeds, at different temperatures, are determined and fitted by the Freundlich equation. The Niwas and the classical methods are applied to the equilibrium data obtained at these different temperatures in order to determine the equilibrium constants. Then, the Van’t Hoff equation is applied to the equilibrium constants in order to determine the standard enthalpy of the sorption reaction. The standard sorption enthalpy is also determined using a new method suggested by the authors, the value is equal to −53.2kJmol−1. The other standard thermodynamic parameters (free standard enthalpy and standard entropy) are deduced. The thermodynamic study shows that rate sorption of the activated carbon from Bois carré seeds increases with the temperature contrarily to the quantity of lead sorbed at equilibrium. [ABSTRACT FROM AUTHOR]