The Experts below are selected from a list of 933 Experts worldwide ranked by ideXlab platform
Kazukiyo Nagai - One of the best experts on this subject based on the ideXlab platform.
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permeability diffusivity and solubility of benzene vapor and water vapor in high free volume silicon or Fluorine Containing Polymer membranes
Journal of Membrane Science, 2010Co-Authors: Shuichi Sato, Shinji Kanehashi, Maiko Suzuki, Kazukiyo NagaiAbstract:The diffusivity, solubility, and permeability of benzene and water vapors, as well as nitrogen (i.e., major component of air) were systematically investigated for high free volume silicon-Containing Polymers, including, poly(dimethylsiloxane) (PDMS), poly(trimethylsilylmethylmethacrylate) (PTMSMMA), poly(1-trimethylsilyl-1-propyne) (PTMSP), Fluorine-Containing 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)-based polyimide. The infinite-dilution permeability coefficient, P0, of benzene vapor and water vapor was diffusion controlled and did not depend on either the mobility of the Polymer segments, the space between Polymer segments, or cohesive energy density of the Polymer but was dependent on the balance among them. In ideal permselectivity, which was determined from pure gas experiments, all silicon-Containing Polymers used in this study showed benzene vapor-permselective behavior while all Fluorine-Containing Polymers had the opposite property (i.e., nitrogen-permselective). All Polymers used in this study showed water vapor-permselective behavior. The benzene vapor/nitrogen permselectivity depended on diffusivity selectivity for Fluorine-Containing Polymers and solubility selectivity for silicon-Containing Polymers. Additionally, the water vapor/nitrogen permselectivity depended on solubility selectivity for PTMSP and some 6FDA-based polyimides with methyl substituent, and both selectivity balance for PDMS, PTMSMMA, and some a 6FDA-based polyimide without methyl substituent.
Maiko Suzuki - One of the best experts on this subject based on the ideXlab platform.
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permeability diffusivity and solubility of benzene vapor and water vapor in high free volume silicon or Fluorine Containing Polymer membranes
Journal of Membrane Science, 2010Co-Authors: Shuichi Sato, Shinji Kanehashi, Maiko Suzuki, Kazukiyo NagaiAbstract:The diffusivity, solubility, and permeability of benzene and water vapors, as well as nitrogen (i.e., major component of air) were systematically investigated for high free volume silicon-Containing Polymers, including, poly(dimethylsiloxane) (PDMS), poly(trimethylsilylmethylmethacrylate) (PTMSMMA), poly(1-trimethylsilyl-1-propyne) (PTMSP), Fluorine-Containing 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)-based polyimide. The infinite-dilution permeability coefficient, P0, of benzene vapor and water vapor was diffusion controlled and did not depend on either the mobility of the Polymer segments, the space between Polymer segments, or cohesive energy density of the Polymer but was dependent on the balance among them. In ideal permselectivity, which was determined from pure gas experiments, all silicon-Containing Polymers used in this study showed benzene vapor-permselective behavior while all Fluorine-Containing Polymers had the opposite property (i.e., nitrogen-permselective). All Polymers used in this study showed water vapor-permselective behavior. The benzene vapor/nitrogen permselectivity depended on diffusivity selectivity for Fluorine-Containing Polymers and solubility selectivity for silicon-Containing Polymers. Additionally, the water vapor/nitrogen permselectivity depended on solubility selectivity for PTMSP and some 6FDA-based polyimides with methyl substituent, and both selectivity balance for PDMS, PTMSMMA, and some a 6FDA-based polyimide without methyl substituent.
Shuichi Sato - One of the best experts on this subject based on the ideXlab platform.
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permeability diffusivity and solubility of benzene vapor and water vapor in high free volume silicon or Fluorine Containing Polymer membranes
Journal of Membrane Science, 2010Co-Authors: Shuichi Sato, Shinji Kanehashi, Maiko Suzuki, Kazukiyo NagaiAbstract:The diffusivity, solubility, and permeability of benzene and water vapors, as well as nitrogen (i.e., major component of air) were systematically investigated for high free volume silicon-Containing Polymers, including, poly(dimethylsiloxane) (PDMS), poly(trimethylsilylmethylmethacrylate) (PTMSMMA), poly(1-trimethylsilyl-1-propyne) (PTMSP), Fluorine-Containing 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)-based polyimide. The infinite-dilution permeability coefficient, P0, of benzene vapor and water vapor was diffusion controlled and did not depend on either the mobility of the Polymer segments, the space between Polymer segments, or cohesive energy density of the Polymer but was dependent on the balance among them. In ideal permselectivity, which was determined from pure gas experiments, all silicon-Containing Polymers used in this study showed benzene vapor-permselective behavior while all Fluorine-Containing Polymers had the opposite property (i.e., nitrogen-permselective). All Polymers used in this study showed water vapor-permselective behavior. The benzene vapor/nitrogen permselectivity depended on diffusivity selectivity for Fluorine-Containing Polymers and solubility selectivity for silicon-Containing Polymers. Additionally, the water vapor/nitrogen permselectivity depended on solubility selectivity for PTMSP and some 6FDA-based polyimides with methyl substituent, and both selectivity balance for PDMS, PTMSMMA, and some a 6FDA-based polyimide without methyl substituent.
Varlamov V.e. - One of the best experts on this subject based on the ideXlab platform.
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Neutron lifetime measurements with a large gravitational trap for ultracold neutrons
'American Physical Society (APS)', 2018Co-Authors: Serebrov A.p., Fomin A.k., Vassiljev A.v., Prudnikov D.m., Chechkin A.v., Chaikovskiy M.e., Kolomensky E.a., Krasnoshchekova I.a., Varlamov V.e.Abstract:International audienceNeutron lifetime is one of the most important physical constants: it determines parameters of the weak interaction and predictions of primordial nucleosynthesis theory. There remains the unsolved problem of a 3.9σ discrepancy between measurements of this lifetime using neutrons in beams and those with stored ultracold neutrons (UCN). In our experiment we measure the lifetime of neutrons trapped by Earth's gravity in an open-topped vessel. Two configurations of the trap geometry are used to change the mean frequency of UCN collisions with the surfaces; this is achieved by plunging an additional surface into the trap without breaking the vacuum. The trap walls are coated with a hydrogen-less Fluorine-Containing Polymer to reduce losses of UCN. The stability of this coating over multiple thermal cycles between 80 and 300 K was tested. At 80 K, the probability of UCN loss due to collisions with the trap walls is just 1.5% of the probability of β decay. The free neutron lifetime is determined by extrapolation to an infinitely large trap with zero collision frequency. The result of these measurements is τn=881.5±0.7stat±0.6systs which is consistent with the conventional value of 880.2 ± 1.0 s presented by the Particle Data Group. Future prospects for this experiment are in further cooling to 10 K, which will lead to an improved accuracy of measurement. In conclusion we present an analysis of currently available data on various measurements of the neutron lifetime
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New Neutron Lifetime Measurements with the Big Gravitational Trap and Review of Neutron Lifetime Data
'Knowledge E', 2017Co-Authors: Serebrov A.p., Kolomensky E. .a., Fomin A.k., Krasnoschekova I.a., Vassiljev A.v., Prudnikov D.m., Chechkin A.v., Chaikovskiy M.e., Varlamov V.e.Abstract:International audienceNeutron lifetime is one of the most important physical constants which determines parameters of the weak interaction and predictions of primordial nucleosynthesis theory. In our experiment we measure the storage time of UCN in the material trap coated with a hydrogen-free Fluorine-Containing Polymer (Fomblin grease UT-18). The stability of this coating to multiple thermal cycles between 80 K and 300 K was tested. The achieved storage time is only 1.5% less than free neutron lifetime. Using additional surface, which can be plunged into the trap to change the collision frequency of UCN with walls, we calculate free neutron lifetime by extrapolation to zero collision frequency. The result of the measurements with this new experimental setup is τn=881.5±0.7stat±0.6systs which is consistent with the conventional value of 880.2±1.0 presented in Particle Data Group. In conclusion, we present an analysis of currently-available data on measurements of neutron
Shinji Kanehashi - One of the best experts on this subject based on the ideXlab platform.
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permeability diffusivity and solubility of benzene vapor and water vapor in high free volume silicon or Fluorine Containing Polymer membranes
Journal of Membrane Science, 2010Co-Authors: Shuichi Sato, Shinji Kanehashi, Maiko Suzuki, Kazukiyo NagaiAbstract:The diffusivity, solubility, and permeability of benzene and water vapors, as well as nitrogen (i.e., major component of air) were systematically investigated for high free volume silicon-Containing Polymers, including, poly(dimethylsiloxane) (PDMS), poly(trimethylsilylmethylmethacrylate) (PTMSMMA), poly(1-trimethylsilyl-1-propyne) (PTMSP), Fluorine-Containing 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)-based polyimide. The infinite-dilution permeability coefficient, P0, of benzene vapor and water vapor was diffusion controlled and did not depend on either the mobility of the Polymer segments, the space between Polymer segments, or cohesive energy density of the Polymer but was dependent on the balance among them. In ideal permselectivity, which was determined from pure gas experiments, all silicon-Containing Polymers used in this study showed benzene vapor-permselective behavior while all Fluorine-Containing Polymers had the opposite property (i.e., nitrogen-permselective). All Polymers used in this study showed water vapor-permselective behavior. The benzene vapor/nitrogen permselectivity depended on diffusivity selectivity for Fluorine-Containing Polymers and solubility selectivity for silicon-Containing Polymers. Additionally, the water vapor/nitrogen permselectivity depended on solubility selectivity for PTMSP and some 6FDA-based polyimides with methyl substituent, and both selectivity balance for PDMS, PTMSMMA, and some a 6FDA-based polyimide without methyl substituent.