The Experts below are selected from a list of 1749 Experts worldwide ranked by ideXlab platform
R Hidalgoalvarez - One of the best experts on this subject based on the ideXlab platform.
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streaming current permeability and microelectrophoresis of polystyrene latices in methanol ethanol mixtures
Journal of Colloid and Interface Science, 2004Co-Authors: O Elgholabzouri, M A Cabrerizovilchez, R HidalgoalvarezAbstract:Abstract The influence of the solvent (methanol–ethanol mixtures) on the electrokinetic behavior of polystyrene latices with sulfate groups was studied (methanol content was increased by 0.2 at a constant KBr concentration of 1 mM). Viscosity, density, and dielectric constant ( η , ρ , and e ) were determined at experimental conditions. Two latices (with different surface charge densities and sizes) were used. Electrophoresis measurements were used for dilute dispersions. Streaming current and hydrodynamic permeability were measured for Porous Plugs. Linear trends in the electrokinetic measurements were observed in the whole molar fraction range. The experimental data obtained from different techniques allow determining the zeta potential according to a well-established classical relationship. The results obtained were analyzed on the basis of the solvent mixture properties and the electrical interface behavior. In addition, permeability data provided valuable information to interpret effects at the solid–liquid interface of the Porous Plug.
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streaming current permeability and microelectrophoresis of polystyrene latices in methanol ethanol mixtures
Journal of Colloid and Interface Science, 2004Co-Authors: O Elgholabzouri, M A Cabrerizovilchez, R HidalgoalvarezAbstract:The influence of the solvent (methanol-ethanol mixtures) on the electrokinetic behavior of polystyrene latices with sulfate groups was studied (methanol content was increased by 0.2 at a constant KBr concentration of 1 mM). Viscosity, density, and dielectric constant (eta, rho, and epsilon) were determined at experimental conditions. Two latices (with different surface charge densities and sizes) were used. Electrophoresis measurements were used for dilute dispersions. Streaming current and hydrodynamic permeability were measured for Porous Plugs. Linear trends in the electrokinetic measurements were observed in the whole molar fraction range. The experimental data obtained from different techniques allow determining the zeta potential according to a well-established classical relationship. The results obtained were analyzed on the basis of the solvent mixture properties and the electrical interface behavior. In addition, permeability data provided valuable information to interpret effects at the solid-liquid interface of the Porous Plug.
O Elgholabzouri - One of the best experts on this subject based on the ideXlab platform.
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streaming current permeability and microelectrophoresis of polystyrene latices in methanol ethanol mixtures
Journal of Colloid and Interface Science, 2004Co-Authors: O Elgholabzouri, M A Cabrerizovilchez, R HidalgoalvarezAbstract:Abstract The influence of the solvent (methanol–ethanol mixtures) on the electrokinetic behavior of polystyrene latices with sulfate groups was studied (methanol content was increased by 0.2 at a constant KBr concentration of 1 mM). Viscosity, density, and dielectric constant ( η , ρ , and e ) were determined at experimental conditions. Two latices (with different surface charge densities and sizes) were used. Electrophoresis measurements were used for dilute dispersions. Streaming current and hydrodynamic permeability were measured for Porous Plugs. Linear trends in the electrokinetic measurements were observed in the whole molar fraction range. The experimental data obtained from different techniques allow determining the zeta potential according to a well-established classical relationship. The results obtained were analyzed on the basis of the solvent mixture properties and the electrical interface behavior. In addition, permeability data provided valuable information to interpret effects at the solid–liquid interface of the Porous Plug.
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streaming current permeability and microelectrophoresis of polystyrene latices in methanol ethanol mixtures
Journal of Colloid and Interface Science, 2004Co-Authors: O Elgholabzouri, M A Cabrerizovilchez, R HidalgoalvarezAbstract:The influence of the solvent (methanol-ethanol mixtures) on the electrokinetic behavior of polystyrene latices with sulfate groups was studied (methanol content was increased by 0.2 at a constant KBr concentration of 1 mM). Viscosity, density, and dielectric constant (eta, rho, and epsilon) were determined at experimental conditions. Two latices (with different surface charge densities and sizes) were used. Electrophoresis measurements were used for dilute dispersions. Streaming current and hydrodynamic permeability were measured for Porous Plugs. Linear trends in the electrokinetic measurements were observed in the whole molar fraction range. The experimental data obtained from different techniques allow determining the zeta potential according to a well-established classical relationship. The results obtained were analyzed on the basis of the solvent mixture properties and the electrical interface behavior. In addition, permeability data provided valuable information to interpret effects at the solid-liquid interface of the Porous Plug.
Yuichiro Ezoe - One of the best experts on this subject based on the ideXlab platform.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard hitomi
Journal of Astronomical Telescopes Instruments and Systems, 2017Co-Authors: Yuichiro Ezoe, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Ryuichi Fujimoto, Kazuhisa Mitsuda, Michael Dipirro, Yoshitaka Ishisaki, Mark O Kimball, Masahide MurakamiAbstract:When using superfluid helium in low-gravity environments, Porous Plug phase separators are commonly used to vent boil-off gas while confining the bulk liquid to the tank. Invariably, there is a flow of superfluid film from the perimeter of the Porous Plug down the vent line. For the soft x-ray spectrometer onboard ASTRO-H (Hitomi), its approximately 30-liter helium supply has a lifetime requirement of more than 3 years. A nominal vent rate is estimated as ∼30 μg/s, equivalent to ∼0.7 mW heat load. It is, therefore, critical to suppress any film flow whose evaporation would not provide direct cooling of the remaining liquid helium. That is, the Porous Plug vent system must be designed to both minimize film flow and to ensure maximum extraction of latent heat from the film. The design goal for Hitomi is to reduce the film flow losses to <2 μg/s, corresponding to a loss of cooling capacity of <40 μW. The design adopts the same general design as implemented for Astro-E and E2, using a vent system composed of a Porous Plug, combined with an orifice, a heat exchanger, and knife-edge devices. Design, on-ground testing results, and in-orbit performance are described.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Proceedings of SPIE, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Suppression of super fluid helium flow is critical for the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi). In nominal operation, a small helium gas flow of ~30 μg/s must be safely vented and a super fluid film flow must be sufficiently small <2 μg/s. To achieve a life time of the liquid helium, a Porous Plug phase separator and a film flow suppression system composed of an orifice, a heat exchanger, and knife edge devices are employed. In this paper, design, on-ground testing results and in-orbit performance of the Porous Plug and the film flow suppression system are described.
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flight model measurements of the Porous Plug and film flow suppression system for the astro h soft x ray spectrometer dewar
Cryogenics, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Abstract Flight model measurements of a Porous Plug phase separator and a film flow suppression system for the ASTRO-H Soft X-ray Spectrometer dewar are described. ASTRO-H is the sixth Japanese astronomy satellite and will be launched in 2016. It carries the Soft X-ray Spectrometer consisting of an X-ray optic and an X-ray microcalorimeter system operated at 50 mK. Superfluid liquid He is employed as a part of the cooling system. A wide range of He flows from 28 μ g/s to 3.2 mg/s in various operation cases must be safely vented under zero gravity. At the same time, superfluid He film flow through the vent line must be suppressed to μ g/s in a nominal case to avoid extra loss of the liquid He. For this purpose, a Porous Plug phase separator together with a film flow suppression system is installed. To verify its performance, the mass flow rates and the film flow rate of the flight model system were measured at component level. The mass flow rates at various He tank temperatures (1.15, 1.30, 1.50, and 2.00 K) were obtained and also the film flow rate was measured at 1.15 K. Then, the mass flow rates were measured after installing the whole system into a flight model dewar at the He tank temperature of 1.16, 1.30, 1.50, and 2.00 K. The dewar was tilted so that the Porous Plug located at the top of the dewar is immersed in the liquid He and the Porous Plug separates the liquid and vapor He by the thermomechanical effect as in orbit. The obtained mass flow rates and the film flow rate in these tests were confirmed to meet the requirements and to be consistent with each other. No abnormal event such as large mass flow rates was observed. All these experimental results strongly suggest that this flight model of the Porous Plug and the film flow suppression system will work properly in space.
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development of Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Cryogenics, 2012Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Hiroya Yamaguchi, Shoji TsunematsuAbstract:Abstract ASTRO-H is the sixth Japanese astronomy satellite scheduled for launch in 2014. The Soft X-ray Spectrometer instrument is onboard ASTRO-H. This is a 6 × 6 array of X-ray microcalorimeters with an energy resolution of
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Porous Plug and superfluid helium film flow suppressor for the soft x ray spectrometer onboard astro h
Cryogenics, 2010Co-Authors: Kumi Ishikawa, Masahide Murakami, Yuichiro Ezoe, Ikuyuki Mitsuishi, Takaya Ohashi, Ryuichi Fujimoto, Kazuhisa Mitsuda, Hiroya Yamaguchi, Hiroshi Yoshitake, Kenichi KanaoAbstract:Abstract Suppression of superfluid helium flow is critical for the Soft X-ray Spectrometer (SXS) onboard Astro-H, to achieve a life time of the liquid helium over 5 years. The superfluid film flow must be sufficiently small, compared to a nominal helium gas flow rate of the SXS ( 25 μ g / s ) . For this purpose, four devices composed of a Porous Plug, an orifice, a heat exchanger, and knife edge devices will be employed based on the experience of the X-ray microcalorimeter (XRS for X-Ray Spectrometer) onboard Suzaku. The Porous Plug is a phase separator of the liquid and gas helium. A potential film flow leaking from the Porous Plug is suppressed by the orifice. Almost all the remaining film flow evaporates at the heat exchanger. The knife edge devices stop the remaining film flow by using atomically sharp edges. In this paper, we describe the principle and design of these four devices.
Kenichi Kanao - One of the best experts on this subject based on the ideXlab platform.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard hitomi
Journal of Astronomical Telescopes Instruments and Systems, 2017Co-Authors: Yuichiro Ezoe, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Ryuichi Fujimoto, Kazuhisa Mitsuda, Michael Dipirro, Yoshitaka Ishisaki, Mark O Kimball, Masahide MurakamiAbstract:When using superfluid helium in low-gravity environments, Porous Plug phase separators are commonly used to vent boil-off gas while confining the bulk liquid to the tank. Invariably, there is a flow of superfluid film from the perimeter of the Porous Plug down the vent line. For the soft x-ray spectrometer onboard ASTRO-H (Hitomi), its approximately 30-liter helium supply has a lifetime requirement of more than 3 years. A nominal vent rate is estimated as ∼30 μg/s, equivalent to ∼0.7 mW heat load. It is, therefore, critical to suppress any film flow whose evaporation would not provide direct cooling of the remaining liquid helium. That is, the Porous Plug vent system must be designed to both minimize film flow and to ensure maximum extraction of latent heat from the film. The design goal for Hitomi is to reduce the film flow losses to <2 μg/s, corresponding to a loss of cooling capacity of <40 μW. The design adopts the same general design as implemented for Astro-E and E2, using a vent system composed of a Porous Plug, combined with an orifice, a heat exchanger, and knife-edge devices. Design, on-ground testing results, and in-orbit performance are described.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Proceedings of SPIE, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Suppression of super fluid helium flow is critical for the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi). In nominal operation, a small helium gas flow of ~30 μg/s must be safely vented and a super fluid film flow must be sufficiently small <2 μg/s. To achieve a life time of the liquid helium, a Porous Plug phase separator and a film flow suppression system composed of an orifice, a heat exchanger, and knife edge devices are employed. In this paper, design, on-ground testing results and in-orbit performance of the Porous Plug and the film flow suppression system are described.
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flight model measurements of the Porous Plug and film flow suppression system for the astro h soft x ray spectrometer dewar
Cryogenics, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Abstract Flight model measurements of a Porous Plug phase separator and a film flow suppression system for the ASTRO-H Soft X-ray Spectrometer dewar are described. ASTRO-H is the sixth Japanese astronomy satellite and will be launched in 2016. It carries the Soft X-ray Spectrometer consisting of an X-ray optic and an X-ray microcalorimeter system operated at 50 mK. Superfluid liquid He is employed as a part of the cooling system. A wide range of He flows from 28 μ g/s to 3.2 mg/s in various operation cases must be safely vented under zero gravity. At the same time, superfluid He film flow through the vent line must be suppressed to μ g/s in a nominal case to avoid extra loss of the liquid He. For this purpose, a Porous Plug phase separator together with a film flow suppression system is installed. To verify its performance, the mass flow rates and the film flow rate of the flight model system were measured at component level. The mass flow rates at various He tank temperatures (1.15, 1.30, 1.50, and 2.00 K) were obtained and also the film flow rate was measured at 1.15 K. Then, the mass flow rates were measured after installing the whole system into a flight model dewar at the He tank temperature of 1.16, 1.30, 1.50, and 2.00 K. The dewar was tilted so that the Porous Plug located at the top of the dewar is immersed in the liquid He and the Porous Plug separates the liquid and vapor He by the thermomechanical effect as in orbit. The obtained mass flow rates and the film flow rate in these tests were confirmed to meet the requirements and to be consistent with each other. No abnormal event such as large mass flow rates was observed. All these experimental results strongly suggest that this flight model of the Porous Plug and the film flow suppression system will work properly in space.
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development of Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Cryogenics, 2012Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Hiroya Yamaguchi, Shoji TsunematsuAbstract:Abstract ASTRO-H is the sixth Japanese astronomy satellite scheduled for launch in 2014. The Soft X-ray Spectrometer instrument is onboard ASTRO-H. This is a 6 × 6 array of X-ray microcalorimeters with an energy resolution of
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Porous Plug and superfluid helium film flow suppressor for the soft x ray spectrometer onboard astro h
Cryogenics, 2010Co-Authors: Kumi Ishikawa, Masahide Murakami, Yuichiro Ezoe, Ikuyuki Mitsuishi, Takaya Ohashi, Ryuichi Fujimoto, Kazuhisa Mitsuda, Hiroya Yamaguchi, Hiroshi Yoshitake, Kenichi KanaoAbstract:Abstract Suppression of superfluid helium flow is critical for the Soft X-ray Spectrometer (SXS) onboard Astro-H, to achieve a life time of the liquid helium over 5 years. The superfluid film flow must be sufficiently small, compared to a nominal helium gas flow rate of the SXS ( 25 μ g / s ) . For this purpose, four devices composed of a Porous Plug, an orifice, a heat exchanger, and knife edge devices will be employed based on the experience of the X-ray microcalorimeter (XRS for X-Ray Spectrometer) onboard Suzaku. The Porous Plug is a phase separator of the liquid and gas helium. A potential film flow leaking from the Porous Plug is suppressed by the orifice. Almost all the remaining film flow evaporates at the heat exchanger. The knife edge devices stop the remaining film flow by using atomically sharp edges. In this paper, we describe the principle and design of these four devices.
Masahide Murakami - One of the best experts on this subject based on the ideXlab platform.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard hitomi
Journal of Astronomical Telescopes Instruments and Systems, 2017Co-Authors: Yuichiro Ezoe, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Ryuichi Fujimoto, Kazuhisa Mitsuda, Michael Dipirro, Yoshitaka Ishisaki, Mark O Kimball, Masahide MurakamiAbstract:When using superfluid helium in low-gravity environments, Porous Plug phase separators are commonly used to vent boil-off gas while confining the bulk liquid to the tank. Invariably, there is a flow of superfluid film from the perimeter of the Porous Plug down the vent line. For the soft x-ray spectrometer onboard ASTRO-H (Hitomi), its approximately 30-liter helium supply has a lifetime requirement of more than 3 years. A nominal vent rate is estimated as ∼30 μg/s, equivalent to ∼0.7 mW heat load. It is, therefore, critical to suppress any film flow whose evaporation would not provide direct cooling of the remaining liquid helium. That is, the Porous Plug vent system must be designed to both minimize film flow and to ensure maximum extraction of latent heat from the film. The design goal for Hitomi is to reduce the film flow losses to <2 μg/s, corresponding to a loss of cooling capacity of <40 μW. The design adopts the same general design as implemented for Astro-E and E2, using a vent system composed of a Porous Plug, combined with an orifice, a heat exchanger, and knife-edge devices. Design, on-ground testing results, and in-orbit performance are described.
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Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Proceedings of SPIE, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Suppression of super fluid helium flow is critical for the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi). In nominal operation, a small helium gas flow of ~30 μg/s must be safely vented and a super fluid film flow must be sufficiently small <2 μg/s. To achieve a life time of the liquid helium, a Porous Plug phase separator and a film flow suppression system composed of an orifice, a heat exchanger, and knife edge devices are employed. In this paper, design, on-ground testing results and in-orbit performance of the Porous Plug and the film flow suppression system are described.
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flight model measurements of the Porous Plug and film flow suppression system for the astro h soft x ray spectrometer dewar
Cryogenics, 2016Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Ikuyuki Mitsuishi, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Shoji TsunematsuAbstract:Abstract Flight model measurements of a Porous Plug phase separator and a film flow suppression system for the ASTRO-H Soft X-ray Spectrometer dewar are described. ASTRO-H is the sixth Japanese astronomy satellite and will be launched in 2016. It carries the Soft X-ray Spectrometer consisting of an X-ray optic and an X-ray microcalorimeter system operated at 50 mK. Superfluid liquid He is employed as a part of the cooling system. A wide range of He flows from 28 μ g/s to 3.2 mg/s in various operation cases must be safely vented under zero gravity. At the same time, superfluid He film flow through the vent line must be suppressed to μ g/s in a nominal case to avoid extra loss of the liquid He. For this purpose, a Porous Plug phase separator together with a film flow suppression system is installed. To verify its performance, the mass flow rates and the film flow rate of the flight model system were measured at component level. The mass flow rates at various He tank temperatures (1.15, 1.30, 1.50, and 2.00 K) were obtained and also the film flow rate was measured at 1.15 K. Then, the mass flow rates were measured after installing the whole system into a flight model dewar at the He tank temperature of 1.16, 1.30, 1.50, and 2.00 K. The dewar was tilted so that the Porous Plug located at the top of the dewar is immersed in the liquid He and the Porous Plug separates the liquid and vapor He by the thermomechanical effect as in orbit. The obtained mass flow rates and the film flow rate in these tests were confirmed to meet the requirements and to be consistent with each other. No abnormal event such as large mass flow rates was observed. All these experimental results strongly suggest that this flight model of the Porous Plug and the film flow suppression system will work properly in space.
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development of Porous Plug phase separator and superfluid film flow suppression system for the soft x ray spectrometer onboard astro h
Cryogenics, 2012Co-Authors: Yuichiro Ezoe, Masahide Murakami, Kumi Ishikawa, Kenichi Kanao, Takaya Ohashi, Ryuichi Fujimoto, Seiji Yoshida, Kazuhisa Mitsuda, Hiroya Yamaguchi, Shoji TsunematsuAbstract:Abstract ASTRO-H is the sixth Japanese astronomy satellite scheduled for launch in 2014. The Soft X-ray Spectrometer instrument is onboard ASTRO-H. This is a 6 × 6 array of X-ray microcalorimeters with an energy resolution of
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Porous Plug and superfluid helium film flow suppressor for the soft x ray spectrometer onboard astro h
Cryogenics, 2010Co-Authors: Kumi Ishikawa, Masahide Murakami, Yuichiro Ezoe, Ikuyuki Mitsuishi, Takaya Ohashi, Ryuichi Fujimoto, Kazuhisa Mitsuda, Hiroya Yamaguchi, Hiroshi Yoshitake, Kenichi KanaoAbstract:Abstract Suppression of superfluid helium flow is critical for the Soft X-ray Spectrometer (SXS) onboard Astro-H, to achieve a life time of the liquid helium over 5 years. The superfluid film flow must be sufficiently small, compared to a nominal helium gas flow rate of the SXS ( 25 μ g / s ) . For this purpose, four devices composed of a Porous Plug, an orifice, a heat exchanger, and knife edge devices will be employed based on the experience of the X-ray microcalorimeter (XRS for X-Ray Spectrometer) onboard Suzaku. The Porous Plug is a phase separator of the liquid and gas helium. A potential film flow leaking from the Porous Plug is suppressed by the orifice. Almost all the remaining film flow evaporates at the heat exchanger. The knife edge devices stop the remaining film flow by using atomically sharp edges. In this paper, we describe the principle and design of these four devices.