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Ivo B Rietveld - One of the best experts on this subject based on the ideXlab platform.
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experimental and topological determination of the pressure Temperature Phase diagram of morniflumate a pharmaceutical ingredient with anti inflammatory properties
The Journal of Chemical Thermodynamics, 2017Co-Authors: Maria Barrio, R. Céolin, Ll J Tamarit, Benoit Robert, Christophe Guechot, Jeanmarie Teulon, Ivo B RietveldAbstract:Abstract The pressure-Temperature Phase diagram of morniflumate (niflumic acid β-morpholinoethyl ester) has been obtained by high-pressure thermal analysis. In addition, calorimetric melting data (TI→L = (348.1 ± 0.4) K and ΔHI→L = (89 ± 2) J·g−1) and the specific volumes of the solid and the liquid state have been obtained under normal pressure. Comparison of the measured high-pressure melting data with the equilibrium curve obtained through the Clapeyron equation indicates that the initial slopes are the same (dP/dT = (2.96 ± 0.06) MPa·K−1) at the melting point under normal pressure. The fact that the Clapeyron equation can be used to construct topological Phase diagrams may be of interest for the food and pharmaceutical industries.
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the topological pressure Temperature Phase diagram of fluoxetine nitrate monotropy unexpectedly turning into enantiotropy
European Physical Journal-special Topics, 2017Co-Authors: R. Céolin, Ivo B RietveldAbstract:The Phase behavior of pharmaceuticals is important for regulatory requirements and dosage form development. Racemic fluoxetine nitrate possesses two crystalline forms for which initial measurements indicated that they have a monotropic relationship with form I the only stable form. By constructing the topological pressure-Temperature Phase diagram, it has been shown that unexpectedly form II has a stable domain in the Phase diagram and can be easily obtained by heating and grinding. The pressure necessary to obtain form II is only 11 MPa, which is much lower than most pressure used for tableting in the pharmaceutical industry.
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the topological pressure Temperature Phase diagram and crystal structures of the dimorphic system spiperone
Annales pharmaceutiques françaises, 2016Co-Authors: Benoit Robert, R. Céolin, Marcantoine Perrin, Gerard Coquerel, Ivo B RietveldAbstract:The topological pressure-Temperature Phase diagram for the dimorphism of spiperone, a potent neuroleptic drug, has been constructed using literature data and improved crystal structures obtained with new crystallographic data from single-crystal X-ray diffraction at various Temperatures. It is inferred that form II, which is the more dense form and exhibits the lower melting Temperature, becomes the more stable Phase under pressure. Under ambient conditions, form I is more stable.
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the topological pressure Temperature Phase diagram of ritonavir an extraordinary case of crystalline dimorphism
Annales pharmaceutiques françaises, 2015Co-Authors: R. Céolin, Ivo B RietveldAbstract:Summary A topological pressure-Temperature Phase diagram involving the Phase relationships of ritonavir forms I and II has been constructed using experimental calorimetric and volumetric data available from the literature. The triple point I-II-liquid is located at a Temperature of about 407 K and a pressure as extraordinarily small as 17.5 MPa (175 bar). Thus, the less soluble solid Phase (form II) will become metastable on increasing pressure. At room Temperature, form I becomes stable around 100 MPa indicating that form II may turn into form I at a relatively low pressure of 1000 bar, which may occur under processing conditions such as mixing or grinding. This case is a good example for which a proper thermodynamic evaluation trumps “rules of thumb” such as the density rule.
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rimonabant dimorphism and its pressure Temperature Phase diagram a delicate case of overall monotropic behavior
Journal of Pharmaceutical Sciences, 2013Co-Authors: Marcantoine Perrin, R. Céolin, Maria Barrio, Michel Bauer, Joseplluis Tamarit, Ivo B RietveldAbstract:Crystalline polymorphism occurs frequently in the solid state of active pharmaceutical ingredients, and this is problematic for the development of a suitable dose form. Rimonabant, an active pharmaceutical ingredient developed by Sanofi and discontinued because of side effects, exhibits dimorphism; both solid forms have nearly the same melting Temperatures, melting enthalpies, and specific volumes. Although the problem may well be academic from an industrial point of view, the present case demonstrates the usefulness of constructing pressure–Temperature Phase diagrams by direct measurement as well as by topological approach. The system is overall monotropic and form II is the more stable solid form. Interestingly, the more stable form does not possess any hydrogen bonds, whereas the less stable one does. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:2311–2321, 2013
Frank Bruno - One of the best experts on this subject based on the ideXlab platform.
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A eutectic salt high Temperature Phase change material: Thermal stability and corrosion of SS316 with respect to thermal cycling
Solar Energy Materials and Solar Cells, 2017Co-Authors: Ming Liu, N. H. Steven Tay, Stuart Bell, Geoffrey Will, Wasim Saman, Mercè Segarra, Frank BrunoAbstract:Thermal energy storage (TES) is a critical component in a concentrated solar power (CSP) plant since it is able to provide dispatchability and increase the capacity factor of the plant. Recently the Brayton power cycle using supercritical carbon dioxide (s-CO2) has attracted considerable attention as it allows a higher thermal to electric power conversion efficiency compared to the conventional Rankine cycle using subcritical steam. However, no commercial TES has yet been developed for integration with a s-CO2based plant. One reason is the lack of a suitable storage material. This work explores the use of a eutectic NaCl-Na2CO3salt as a reliable high Temperature Phase change material (PCM). The PCM has been thermally cycled up to 1000 times. Its thermo-physical properties have been measured before and after it has been subjected to the thermal cycling and its corrosion behavior has been investigated. This eutectic salt shows good thermal stability without degradation after cycling 1000 times between 600 and 650 °C. The corrosion rate on stainless steel 316 (SS316) increases linearly up to 350 cycles, and thereafter it stabilizes at 70 mg/cm2.
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review on storage materials and thermal performance enhancement techniques for high Temperature Phase change thermal storage systems
Renewable & Sustainable Energy Reviews, 2012Co-Authors: Ming Liu, Wasim Saman, Frank BrunoAbstract:Abstract Designing a cost-effective Phase change thermal storage system involves two challenging aspects: one is to select a suitable storage material and the other is to increase the heat transfer between the storage material and the heat transfer fluid as the performance of the system is limited by the poor thermal conductivity of the latent heat storage material. When used for storing energy in concentrated solar thermal power plants, the solar field operation Temperature will determine the PCM melting Temperature selection. This paper reviews concentrated solar thermal power plants that are currently operating and under construction. It also reviews Phase change materials with melting Temperatures above 300 °C, which potentially can be used as energy storage media in these plants. In addition, various techniques employed to enhance the thermal performance of high Temperature Phase change thermal storage systems have been reviewed and discussed. This review aims to provide the necessary information for further research in the development of cost-effective high Temperature Phase change thermal storage systems.
Ming Liu - One of the best experts on this subject based on the ideXlab platform.
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A eutectic salt high Temperature Phase change material: Thermal stability and corrosion of SS316 with respect to thermal cycling
Solar Energy Materials and Solar Cells, 2017Co-Authors: Ming Liu, N. H. Steven Tay, Stuart Bell, Geoffrey Will, Wasim Saman, Mercè Segarra, Frank BrunoAbstract:Thermal energy storage (TES) is a critical component in a concentrated solar power (CSP) plant since it is able to provide dispatchability and increase the capacity factor of the plant. Recently the Brayton power cycle using supercritical carbon dioxide (s-CO2) has attracted considerable attention as it allows a higher thermal to electric power conversion efficiency compared to the conventional Rankine cycle using subcritical steam. However, no commercial TES has yet been developed for integration with a s-CO2based plant. One reason is the lack of a suitable storage material. This work explores the use of a eutectic NaCl-Na2CO3salt as a reliable high Temperature Phase change material (PCM). The PCM has been thermally cycled up to 1000 times. Its thermo-physical properties have been measured before and after it has been subjected to the thermal cycling and its corrosion behavior has been investigated. This eutectic salt shows good thermal stability without degradation after cycling 1000 times between 600 and 650 °C. The corrosion rate on stainless steel 316 (SS316) increases linearly up to 350 cycles, and thereafter it stabilizes at 70 mg/cm2.
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Determination of thermo-physical properties and stability testing of high-Temperature Phase-change materials for CSP applications
Solar Energy Materials and Solar Cells, 2015Co-Authors: Ming Liu, N. H.s. Tay, Craig S Turchi, Wasim Saman, J C Gomez, Fulvio BrunoAbstract:This paper presents the thermo-physical properties and stability testing results of six high-Temperature Phase-change candidate materials for potential use as a cascaded storage system for concentrating solar power applications. This type of storage is a promising technology because it offers a higher utilization of the possible Phase change and a more uniform heat-transfer fluid outlet Temperature, compared with the single Phase-change material (PCM) storage system. The tested materials were inorganic eutectic PCMs with reported Phase-change Temperatures between 300 °C and 600 °C. Four PCMs were made from carbonate salts (Na2CO3, K2CO3, and Li2CO3) and two from chloride salts (NaCl, MgCl2, and KCl). The Phase-change Temperature, Phase-change enthalpy, and specific heat of these PCMs were measured using a differential scanning calorimeter. Large material samples were tested in an oven subjected to multiple melt-freeze cycles. The results showed that the carbonate PCMs have a very high degree of sub-cooling in the initial cycles, which decreased in subsequent cycles. The chloride PCMs have a negligible degree of sub-cooling. There is some disagreement between the measured and reported thermo-physical property values of the tested materials, which demonstrates the uncertainty associated with published property values. One carbonate PCM and one chloride PCM were recommended as promising latent heat storage materials.
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review on storage materials and thermal performance enhancement techniques for high Temperature Phase change thermal storage systems
Renewable & Sustainable Energy Reviews, 2012Co-Authors: Ming Liu, Wasim Saman, Frank BrunoAbstract:Abstract Designing a cost-effective Phase change thermal storage system involves two challenging aspects: one is to select a suitable storage material and the other is to increase the heat transfer between the storage material and the heat transfer fluid as the performance of the system is limited by the poor thermal conductivity of the latent heat storage material. When used for storing energy in concentrated solar thermal power plants, the solar field operation Temperature will determine the PCM melting Temperature selection. This paper reviews concentrated solar thermal power plants that are currently operating and under construction. It also reviews Phase change materials with melting Temperatures above 300 °C, which potentially can be used as energy storage media in these plants. In addition, various techniques employed to enhance the thermal performance of high Temperature Phase change thermal storage systems have been reviewed and discussed. This review aims to provide the necessary information for further research in the development of cost-effective high Temperature Phase change thermal storage systems.
G V Shlyapnikov - One of the best experts on this subject based on the ideXlab platform.
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quantum monte carlo calculation of the zero Temperature Phase diagram of the two component fermionic hard core gas in two dimensions
Physical Review B, 2011Co-Authors: Neil Drummond, N R Cooper, R J Needs, G V ShlyapnikovAbstract:Motivated by potential realizations in cold-atom or cold-molecule systems, we have performed quantum Monte Carlo simulations of two-component gases of fermions in two dimensions with hard-core interactions. We have determined the gross features of the zero-Temperature Phase diagram by investigating the relative stabilities of paramagnetic and ferromagnetic fluids and crystals. We have also examined the effect of including a pairwise, long-range ${r}^{\ensuremath{-}3}$ potential between the particles. Our most important conclusion is that there is no region of stability for a ferromagnetic fluid Phase, even if the long-range interaction is present. We also present results for the pair-correlation function, static structure factor, and momentum density of two-dimensional hard-core fluids.
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a finite Temperature Phase transition for disordered weakly interacting bosons in one dimension
Nature Physics, 2010Co-Authors: I L Aleiner, B L Altshuler, G V ShlyapnikovAbstract:It is commonly accepted that there are no Phase transitions in one-dimensional systems at a finite Temperature, because long-range correlations are destroyed by thermal fluctuations. Here we show theoretically that the one-dimensional gas of short-range interacting bosons in the presence of disorder can undergo a finite-Temperature Phase transition between two distinct states: fluid and insulator. Neither of these states has long-range spatial correlations, but this is a true, albeit non-conventional, Phase transition, because transport properties are singular at the transition point. In the fluid Phase, mass transport is possible, whereas in the insulator Phase it is completely blocked even at finite Temperatures. This study thus provides insight into how the interaction between disordered bosons influences their Anderson localization. This question, first raised for electrons in solids, is now crucial for the studies of atomic bosons, where recent experiments have demonstrated Anderson localization in expanding dilute quasi-one-dimensional clouds.
Yongping Yang - One of the best experts on this subject based on the ideXlab platform.
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selection principles and thermophysical properties of high Temperature Phase change materials for thermal energy storage a review
Renewable & Sustainable Energy Reviews, 2018Co-Authors: Gaosheng Wei, Gang Wang, Lijing Xing, Yongping YangAbstract:Abstract Phase change thermal energy storage (TES) is a promising technology due to the large heat capacity of Phase change materials (PCM) during the Phase change process and their potential thermal energy storage at nearly constant Temperature. Although a considerable amount of research has been conducted on medium and low Temperature PCMs in recent years, there has been a lack of a similar systematic and integrated study on high Temperature PCMs and high Temperature thermal energy storage processes. Analyzing the available literature, this review evaluates the selection principles of PCMs and introduces and compares the available popular material selection software options. The thermophysical property data of high Temperature PCMs is comprehensively summarized, including high Temperature molten salts and metal alloys. Several heat transfer and performance enhancement techniques are summarized and discussed as potential alternative methods to overcome poor thermal conductivity when using high Temperature molten salt as the PCM. The common thermophysical property measurement methods used in literature are also summarized and compared. This review gives a broad overview of material selection, innovation and investigation of thermophysical properties for high Temperature PCM development, and will be a helpful reference for the design of high Temperature Phase change TES systems.
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numerical analysis of thermal storage performance with high Temperature Phase change materials operated by condensing steam
Solar Energy, 2015Co-Authors: Xing Ju, Chao Xu, Xianglin Li, Xiaoze Du, Yongping YangAbstract:Abstract This paper numerically investigated the heat storage behaviors of a shell-and-tube storage unit filled with high-Temperature Phase change material (PCM) using steam as the heat transfer fluid. A two dimensional heat transfer model using the enthalpy method was established, and the characteristics of the variations in the PCM melting time, charging rates from the steam to the PCM, and the steam condensation with time were studied. The influences of the thermal conductivity of PCM, the steam flow rate and the diameter ratio on the charging performance were evaluated. The results show that the heat charging rate can be not only significantly increased by increasing the PCM thermal conductivity, but also considerably increased by increasing the steam flow rate or decreasing the diameter ratio. As a result, the total charging time decreases with the increase of the PCM thermal conductivity or the decrease of the diameter ratio, and it can also be regulated by adjusting the steam flow rate. The liquefaction ratio can also be increased by increasing the PCM thermal conductivity during the design procedure, and can be effectively regulated by varying the steam flow rate during the operation.
