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Matthew W Bowler - One of the best experts on this subject based on the ideXlab platform.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    Journal of Applied Crystallography, 2017
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The Humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative Humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The Controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, leading to higher diffraction quality. Devices that can accurately Control the Humidity surrounding crystals while monitoring diffraction have led to this technique being increasingly adopted, as the experiments become easier and more reproducible. Matching the RH to the mother liquor is the first step in allowing the stable mounting of a crystal. In previous work [Wheeler, Russi, Bowler & Bowler (2012). Acta Cryst. F68, 111–114], the equilibrium RHs were measured for a range of concentrations of the most commonly used precipitants in macromolecular crystallography and it was shown how these related to Raoult's law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between the measured values and those predicted by theory could not be explained. Here, a more precise Humidity Control device has been used to determine equilibrium RH points. The new results are in agreement with Raoult's law. A simple argument in statistical mechanics is also presented, demonstrating that the equilibrium vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult's law. The same argument can be extended to the case where the solvent and solute molecules are of different sizes, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding a sample.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    arXiv: Soft Condensed Matter, 2016
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The equilibrium relative Humidity values for a number of the most commonly used precipitants in biological macromolecule crystallisation have been measured using a new Humidity Control device. A simple argument in statistical mechanics demonstrates that the saturated vapour pressure of a solvent is proportional to its mole fraction in an ideal solution (Raoult's Law). The same argument can be extended to the case where solvent and solute molecules are of different size.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    bioRxiv, 2016
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The Humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative Humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The Controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, which often leads to higher diffraction quality. Devices that can accurately Control the Humidity surrounding crystals on a beamline have led to this technique being increasingly adopted, as experiments become easier and more reproducible. Matching the relative Humidity to the mother liquor is the first step to allow the stable mounting of a crystal. In previous work, we measured the equilibrium relative Humidity for a range of concentrations of the most commonly used precipitants and showed how this related to Raoult9s law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between measured values and those predicted by theory could not be explained. Here, we have used a more precise Humidity Control device to determine equilibrium relative Humidity points. The new results are in agreement with Raoult9s law. We also present a simple argument in statistical mechanics demonstrating that the saturated vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult9s Law. The same argument can be extended to the case where solvent and solute molecules are of different size, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding samples.

Dinhhieu Vu - One of the best experts on this subject based on the ideXlab platform.

  • Humidity Control materials prepared from diatomite and volcanic ash
    Construction and Building Materials, 2013
    Co-Authors: Dinhhieu Vu, Kuensheng Wang
    Abstract:

    Abstract The preparation of Humidity Control materials has been studied by sintering a mixture of diatomite and volcanic ash with and without the addition of sodium perborate. The final products were analyzed to identify moisture adsorption–desorption performances, porous and mechanical properties. In addition, effects of sintering temperature and various mixed portions on the final products were also investigated. The sintered products have mesoporous structure with the pore diameter tends to be in the range of 2–50 nm, and the porous properties reach from 14.1 ± 1 to 65 ± 3 m2/g in BET surface area and from 65.23 ± 3 to 70.84 ± 5% in porosity. In addition, moisture adsorption–desorption ability of the Humidity Control materials increases as diatomite content increases. The results indicate that the adsorbed moisture amount of the best products manufactured from the mixture of 90% diatomite, 8% volcanic ash and 2% sodium perborateat sintering temperature of 1000° C and 1100° C reach 65 ± 4 and 55 ± 2 g/m2, respectively. The best products show excellent performance as a Humidity Control building material with fine mechanical properties and can be used for various construction applications at low cost.

  • Humidity Control porous ceramics prepared from waste and porous materials
    Materials Letters, 2011
    Co-Authors: Dinhhieu Vu, Kuensheng Wang
    Abstract:

    Abstract This study investigated the feasibility of generating Humidity Control porous ceramics by sintering a mixture of volcanic ash, weathered volcanic ash, and waste glass. The sintering conditions, including sintering time, sintering temperature, and various mixed portions of glass amendment, were tested. The final ceramics were analyzed for their pore distribution, pore volume, adsorption and desorption characteristics, and bending strength. The results indicate that the pore size of the volcanic ash ceramics tends to distribute in the range from 70 to 100 nm, whereas that of the weathered volcanic ash ceramics is in the range of 7–9 nm. The Humidity Controlling conditions of the ceramics take advantage of the inherent porosity of the natural materials. The bending strengths in both cases were all satisfying with the fractural intensity specification of ceramics (> 6 Mpa).

Kuensheng Wang - One of the best experts on this subject based on the ideXlab platform.

  • Humidity Control materials prepared from diatomite and volcanic ash
    Construction and Building Materials, 2013
    Co-Authors: Dinhhieu Vu, Kuensheng Wang
    Abstract:

    Abstract The preparation of Humidity Control materials has been studied by sintering a mixture of diatomite and volcanic ash with and without the addition of sodium perborate. The final products were analyzed to identify moisture adsorption–desorption performances, porous and mechanical properties. In addition, effects of sintering temperature and various mixed portions on the final products were also investigated. The sintered products have mesoporous structure with the pore diameter tends to be in the range of 2–50 nm, and the porous properties reach from 14.1 ± 1 to 65 ± 3 m2/g in BET surface area and from 65.23 ± 3 to 70.84 ± 5% in porosity. In addition, moisture adsorption–desorption ability of the Humidity Control materials increases as diatomite content increases. The results indicate that the adsorbed moisture amount of the best products manufactured from the mixture of 90% diatomite, 8% volcanic ash and 2% sodium perborateat sintering temperature of 1000° C and 1100° C reach 65 ± 4 and 55 ± 2 g/m2, respectively. The best products show excellent performance as a Humidity Control building material with fine mechanical properties and can be used for various construction applications at low cost.

  • Humidity Control porous ceramics prepared from waste and porous materials
    Materials Letters, 2011
    Co-Authors: Dinhhieu Vu, Kuensheng Wang
    Abstract:

    Abstract This study investigated the feasibility of generating Humidity Control porous ceramics by sintering a mixture of volcanic ash, weathered volcanic ash, and waste glass. The sintering conditions, including sintering time, sintering temperature, and various mixed portions of glass amendment, were tested. The final ceramics were analyzed for their pore distribution, pore volume, adsorption and desorption characteristics, and bending strength. The results indicate that the pore size of the volcanic ash ceramics tends to distribute in the range from 70 to 100 nm, whereas that of the weathered volcanic ash ceramics is in the range of 7–9 nm. The Humidity Controlling conditions of the ceramics take advantage of the inherent porosity of the natural materials. The bending strengths in both cases were all satisfying with the fractural intensity specification of ceramics (> 6 Mpa).

Michael G Bowler - One of the best experts on this subject based on the ideXlab platform.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    Journal of Applied Crystallography, 2017
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The Humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative Humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The Controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, leading to higher diffraction quality. Devices that can accurately Control the Humidity surrounding crystals while monitoring diffraction have led to this technique being increasingly adopted, as the experiments become easier and more reproducible. Matching the RH to the mother liquor is the first step in allowing the stable mounting of a crystal. In previous work [Wheeler, Russi, Bowler & Bowler (2012). Acta Cryst. F68, 111–114], the equilibrium RHs were measured for a range of concentrations of the most commonly used precipitants in macromolecular crystallography and it was shown how these related to Raoult's law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between the measured values and those predicted by theory could not be explained. Here, a more precise Humidity Control device has been used to determine equilibrium RH points. The new results are in agreement with Raoult's law. A simple argument in statistical mechanics is also presented, demonstrating that the equilibrium vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult's law. The same argument can be extended to the case where the solvent and solute molecules are of different sizes, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding a sample.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    arXiv: Soft Condensed Matter, 2016
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The equilibrium relative Humidity values for a number of the most commonly used precipitants in biological macromolecule crystallisation have been measured using a new Humidity Control device. A simple argument in statistical mechanics demonstrates that the saturated vapour pressure of a solvent is proportional to its mole fraction in an ideal solution (Raoult's Law). The same argument can be extended to the case where solvent and solute molecules are of different size.

  • raoult s law revisited accurately predicting equilibrium relative Humidity points for Humidity Control experiments
    bioRxiv, 2016
    Co-Authors: Michael G Bowler, D R Bowler, Matthew W Bowler
    Abstract:

    The Humidity surrounding a sample is an important variable in scientific experiments. Biological samples in particular require not just a humid atmosphere but often a relative Humidity (RH) that is in equilibrium with a stabilizing solution required to maintain the sample in the same state during measurements. The Controlled dehydration of macromolecular crystals can lead to significant increases in crystal order, which often leads to higher diffraction quality. Devices that can accurately Control the Humidity surrounding crystals on a beamline have led to this technique being increasingly adopted, as experiments become easier and more reproducible. Matching the relative Humidity to the mother liquor is the first step to allow the stable mounting of a crystal. In previous work, we measured the equilibrium relative Humidity for a range of concentrations of the most commonly used precipitants and showed how this related to Raoult9s law for the equilibrium vapour pressure of water above a solution. However, a discrepancy between measured values and those predicted by theory could not be explained. Here, we have used a more precise Humidity Control device to determine equilibrium relative Humidity points. The new results are in agreement with Raoult9s law. We also present a simple argument in statistical mechanics demonstrating that the saturated vapour pressure of a solvent is proportional to its mole fraction in an ideal solution: Raoult9s Law. The same argument can be extended to the case where solvent and solute molecules are of different size, as is the case with polymers. The results provide a framework for the correct maintenance of the RH surrounding samples.

J F Young - One of the best experts on this subject based on the ideXlab platform.

  • Humidity Control in the laboratory using salt solutions a review
    Journal of Chemical Technology & Biotechnology, 2007
    Co-Authors: J F Young
    Abstract:

    The relative humidities maintained over saturated and unsaturated salt solutions and of some salt hydrate mixtures have been collated from the literature over a wide range of temperature. Results are presented for 38 saturated salt solutions, and details listed for salts which are recommended as suitable for Humidity Control. The Control of Humidity in the laboratory by the use of salt solutions is critically discussed.