Empirical investigation to explore potential gains from the amalgamation of Phase Changing Materials (PCMs) and wood shavings

The reduction of gained heat, heat peak shifting and the mitigation of air temperature fluctuations are some desirable properties that are sought after in any thermal insulation system. It cannot be overstated that these factors, in addition to others, govern the performance of such systems thus their effect on indoor ambient conditions. The effect of such systems extends also to Heating, Ventilation and Air-conditioning (HVAC) systems that are set up to operate optimally in certain conditions. Where literature shows that PCMs and natural materials such as wood-shavings can provide efficient passive insulation for buildings, it is evident that such approaches utilise methods that are of a degree of intricacy which requires specialist knowledge and complex techniques, such as micro-encapsulation for instance. With technical and economic aspects in mind, an amalgam of PCM and wood-shavings has been created for the purpose of being utilised as a feasible thermal insulation. The amalgamation was performed in the simplest of methods, through submerging the wood shavings in PCM. An experimental procedure was devised to test the thermal performance of the amalgam and compare this to the performance of the same un-amalgamated materials. Comparative analysis revealed that no significant thermal gains would be expected from such amalgamation. However, significant reduction in the total weight of the insulation system would be achieved that, in this case, shown to be up to 20.94%. Thus, further reducing possible strains on structural elements due to the application of insulation on buildings. This can be especially beneficial in vernacular architectural approaches where considerably large amounts and thicknesses of insulations are used. In addition, cost reduction could be attained as wood shavings are significantly cheaper compared to the cost of PCMs

Purification of Propylene and Ethylene by a Robust Metal–Organic Framework Mediated by Host–Guest Interactions

From Wiley via Jisc Publications RouterHistory: received 2021-03-19, pub-electronic 2021-06-07Article version: VoRPublication status: PublishedFunder: Engineering and Physical Sciences Research Council; Id: http://dx.doi.org/10.13039/501100000266; Grant(s): EP/I011870, EP/R00661X/1, EP/S019367/1, EP/P025021/1, EP/P025498/1Funder: European Research Council; Id: http://dx.doi.org/10.13039/501100000781; Grant(s): 742401Abstract: Industrial purification of propylene and ethylene requires cryogenic distillation and selective hydrogenation over palladium catalysts to remove propane, ethane and/or trace amounts of acetylene. Here, we report the excellent separation of equimolar mixtures of propylene/propane and ethylene/ethane, and of a 1/100 mixture of acetylene/ethylene by a highly robust microporous material, MFM‐520, under dynamic conditions. In situ synchrotron single crystal X‐ray diffraction, inelastic neutron scattering and analysis of adsorption thermodynamic parameters reveal that a series of synergistic host–guest interactions involving hydrogen bonding and π⋅⋅⋅π stacking interactions underpin the cooperative binding of alkenes within the pore. Notably, the optimal pore geometry of the material enables selective accommodation of acetylene. The practical potential of this porous material has been demonstrated by fabricating mixed‐matrix membranes comprising MFM‐520, Matrimid and PIM‐1, and these exhibit not only a high permeability for propylene (≈1984 Barrer), but also a separation factor of 7.8 for an equimolar mixture of propylene/propane at 298 K

From the imprints of French poetry to the expression of committed Persian poetry : the case of Ahmad Shâmlou and Nimâ Yushidj

Dans cette thèse de littérature comparée, plus qu’une histoire politique des poètes Nimâ Yushidj et Ahmad Shâmlou, nous avons cherché à comprendre comment ceux-ci négocient les rapports entre champ politique et champ poétique. Alors que la modernité consiste, selon Baudelaire, à « dépolitiser » les auteurs, l'engagement de la poésie persane est pourtant l’un des enjeux de la littérature moderne en Iran. Comment peut-on trouver des expressions alternatives pour définir cette étrange alliance entre poésie et politique ? Nimâ Yushidj (1895- 1960) et Ahmad Shâmlou (1925-2000) sont deux poètes les plus lus et les figures poétiques les plus marquantes de la littérature persane moderne. Dans la foulée de la Révolution constitutionnelle persane (ou la période dite Mashroutiat) en 1905, ils ont contribué à libérer leur expression poétique par un style raffiné et conforme à leur temps. En prenant des images puisées dans la poésie française, ils ont conçu une particularité poétique sur le modèle français, mais dans le contexte de leur société. Ils ont créé ainsi une hybridation littéraire et identitaire qui confronte les vestiges d'un traditionalisme à la modernité. Comment peut-on traiter une littérature sans être absent du débat et sans entrer en contact avec l'Histoire et l'actualité ? Pourquoi la question de l'engagement a-t-elle si explicitement été poursuivie par ces deux poètes persans du XXe siècle ? Comment rendre au fait littéraire, en principe affranchi du politique et de ses contraintes, son autonomie et sa spécificité ? Cette thèse cherche à répondre à ces différentes questions.In this comparative literature thesis, rather than a political history of the poets Nimâ Yushidj and Ahmad Shâmlou, we have sought to understand how they negotiate the relationship between political and poetic fields. While modernity consists, according to Baudelaire, in "depoliticizing" authors, the commitment of Persian poetry is nevertheless one of the issues of modern literature in Iran. How can we find alternative expressions to define this strange alliance between poetry and politics? Nimâ Yushidj (1895- 1960) and Ahmad Shâmlou (1925-2000) are two of the most widely read poets and the most prominent poetic figures in modern Persian literature. In the wake of the Persian Constitutional Revolution (or the so-called Mashroutiat period) in 1905, they contributed to the liberation of their poetic expression through a refined style in keeping with their time. By taking images from French poetry, they designed a poetic particularity on the French model, but in the context of their society. In this way, they created a literary and identity hybridization that confronts the vestiges of traditionalism with modernity. How can one deal with literature without being absent from the debate and without coming into contact with history and current events? Why has the question of commitment been so explicitly pursued by these two twentieth-century Persian poets? How can we give back to the literary fact, in principle freed from politics and its constraints, its autonomy and its specificity? This thesis seeks to answer these different questions. In this thesis of comparative literature, more than a political history of the poets Nima Yushidj and Ahmad Shâmlou, we sought to understand how they negotiate the relations between the political field and the poetic field. While modernity consists, according to Baudelaire, in «depoliticizing» the authors, the commitment of Persian poetry is nevertheless one of the stakes of modern literature in Iran. How can we find alternative expressions to define this strange alliance between poetry and politics? Nimâ Yushidj (1895-1960) and Ahmad Shâmlou (1925-2000) are two of the most widely read poets and poetic figures in modern Persian literature. In the wake of the Persian Constitutional Revolution (or the so-called Mashroutiat period) in 1905, they helped to liberate their poetic expression by a refined style in keeping with their time. By taking images drawn from French poetry, they have conceived a poetic peculiarity on the French model, but in the context of their society. They have thus created a literary and identity hybridization that confronts the vestiges of traditionalism with modernity. How can a literature be treated without being absent from the debate and without coming into contact with history and current events? Why was the question of commitment so explicitly pursued by these two 20th century Persian poets? How can we return to the literary fact, in principle free from politics and its constraints, its autonomy and its specificity? This thesis seeks to answer these different questions

Optimum operating conditions for a combined power and cooling thermodynamic cycle

The combined production of thermal power and cooling with an ammonia-water based cycle proposed by Goswami is under intensive investigation. In the cycle under consideration, simultaneous cooling output is produced by expanding an ammonia-rich vapor in an expander to sub-ambient temperatures and subsequently heating the cool exhaust. When this mechanism for cooling production is considered in detail, it is apparent that the cooling comes at some expense to work production. To optimize this trade-off, a very specific coefficient-of-performance has been defined. In this paper, the simulation of the cycle was carried out in the process simulator ASPEN Plus. The optimum operating conditions have been found by using the Equation Oriented mode of the simulator and some of the results have been compared with the experimental data obtained from the cycle. The agreement between the two sets proves the accuracy of the optimization results.Ammonia cycle Cooling Power Aspen simulation Optimization

Development of a Molecular Kinetic Model and Tuning of its Required Kinetic Parameters for Thermal Cracking of Light Hydrocarbons

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A novel bio-based phase change material of methyl palmitate and decanoic acid eutectic mixture: Thermodynamic modeling and thermal performance

One of the most sustainable methods of energy management is thermal energy storage using renewable phase change materials. Phase change materials (PCMs) with high latent heat can store thermal energy when available and release it effectively when required. In this study, the thermal properties of a set of binary mixtures of methyl palmitate (MP) and decanoic acid (DA) have been evaluated as a new bio-based and renewable PCM. Both phase change materials are obtained from vegetable oil and are biomass-based materials. The results show that the binary eutectic mixture consisting of 30% MP and 70% DA has the desired properties as a PCM for applying as thermal energy storage in the building materials. These features include the convenient melting and freezing temperatures (Tm = 20.19 °C, Tf = 15.08 °C) and the high value of corresponding latent heats (ΔHf =202.3 J.g−1, ΔHm = 201.43 J.g−1). Evaluating other thermo-physical properties of this mixture also confirms its fitness for the PCM role. The composition and melting point of the eutectic point and the solid-liquid phase equilibrium for these mixtures were predicted by several thermodynamic models from which UNIQUAC showed the lowest Average Relative Deviation percentage (ARD%) of 0.29%