22A01

航空機実験用超臨界状態光化学反応装置の開発○夏井坂誠（宇宙航空研究開発機構），西山靖浩，垣内喜代三（奈良先端科学技術大学院大学），
永澤眞，松本雅光（㈱シン・コーポレーション），井上佳久（大阪大学），出口茂（海洋研究開発機構）

Development of a Compact Photoreactor for Parabolic Flight Experiments in Supercritical Fluids
Makoto NATSUISAKA (Japan Aerospace Exploration Agency), Yasuhiro NISHIYAMA, Kiyomi KAKIUCHI(Nara Institute of Science and Technology), Makoto NAGASAWA, Masamitsu MATSUMOTO(Syn Corporation), Yoshihisa INOUE (Osaka University), Shigeru DEGUCHI(Japan Agency for Marine-Earth Science and Technology)

1. Objectives

2.

Chiral photochemistry is one of the most intriguing andchallenging topics in current chemistry. We performed theenantiodifferentiating photoisomerization of (Z)-cyclooctene(1Z) to (E)-isomer (1E) sensitized by optically active menthyl(Men), 8-phenylmenthyl (8Ph-Men) and diacetone fructose(DAF) pyromellitates (Pyro) (Fig. 1) in organic solvents toreveal that the enantiomeric excesses (ee’s) of 1E can becontrolled by temperature, pressure, and solvent. Interestingly,
the product’s ee showed a dramatic, discontinuous dependence
on pressure when the photosensitization was carried out in nearcritical (nc) and supercritical (sc) CO2 (Fig. 2) 1). The results arerationalized by the variation in CO2 clustering around theintervening exciplex, which is affected by the density
fluctuation of nc/scCO2 and therefore expected to be
exaggerated under microgravity. To verify this, a compact
photoreactor for parabolic flight experiments in supercriticalfluid was newly developed.

Compact Photoreactor for Parabolic FlightExperiments in Supercritical Fluids

Fig. 3 illustrates the components of the photoreactor. The
reaction cells (shown as “SC-Cells” in the figure) are made ofsapphire tubes to enclose the high pressure of supercritical CO2.
The internal dimension of the cell was 5.9 mm  x 34 mm =0.93 cm3. Three identical cells surrounding a UV lamp ( = 254nm) were heated with silicone rubber-coated heaters up to thereaction temperature (45 °C). The temperature was controlledwith a microcomputer (shown as “dsPIC” in Fig. 3) bymonitoring the inside temperature of each cell. The UV lamp
was automatically switched on/off when the z-axis G becomes
smaller than a preset threshold with the microcomputer bymonitoring the gravity level with a G-sensor. The experimental
parameters, including acceleration (3 axes), inside temperatureof each cell and photodiode output monitoring the UV intensity,
were recorded with a data logger. It was verified that thetemperature (fluctuation within ±1 °C) and UV illumination(Fig. 4) were accurately controlled by the system throughout theactual parabolic flights.

Fig. 1 Enantiodifferentiating photoisomerization of 1Z
sensitized by a variety of chiral pyromellitates.
Fig. 3Fig. 4Components of the photoreactor

Control of the llumination of UV lamp.

References
1)Fig. 2Pressure effect on the ee of 1E.

− J 56 −R. Saito, M. Kaneda; T. Wada; A. Katoh and Y. Inoue: Chem.
Lett,.(2002) 860.

22A02

航空機実験用ハニカムフィルム作製装置の開発○夏井坂誠（宇宙航空研究開発機構），金原雅晃，齊藤祐太，平井悠司，藪浩，下村政嗣（東北大学），
辻井薫（元・北海道大学）

Development of Honeycomb Film Fabrication Apparatus for Parabolic Flights
Makoto NATSUISAKA (Japan Aerospace Exploration Agency), Masaaki KANEHARA, Yuta SAITO, Yuji HIRAI,
Hiroshi YABU, Masatsugu SHIMOMURA (Tohoku Univ.), Kaoru TSUJII (Hokkaido Univ. (retired))

1. Objectives
Shimomura et al found that fine porous polymer films(“honeycomb films”) could be obtained when water vapor wasadded to casted polymer solutions1,2). Although the protocol isvery simple, the uniformity and ordering of the pores are quite
fine (see Fig. 1). Various applications have been investigatedand for those larger films are desired. However unwanted
domain formation (see Fig. 2) is often observed and preventing
the honeycomb films from providing maximum capabilities tothe applications. The authors speculate that this might arise fromnatural convections due to gravity and has tried low gravity
experiments with parabolic flights to avoid the effect of thenatural convections.

Fig. 1value, the solenoid valve inserted in the exhausted line will be
opened to start casting and then, a few seconds after, anotherelectrical valve inserted in the water vapor line will be opened
to start vapor condensation onto the surface of the casted
polymer solution. The process of the film formation is recordedwith a video camera. The first parabolic flight experiments weretried in May, 2011, but acceleration just before a microgravity
period and an air flow to the exhaust and from water vapor lines
deformed the surface of the solutions. To avoid this, the new
apparatus employed a swing arm mechanism and a novel designfor the cell part. The second parabolic flights were carried out in
Dec. 2011 and the new apparatus succeed to eliminate thesurface deformation.

Fabrication of a honey comb film

Fig. 2

Fig. 3

Honeycomb film fabrication apparatus

Fig. 4

Schematic representation of the cell

Domain formation

2. Parabolic Flight Experiments
The components of the honeycomb film fabrication apparatus
for parabolic flights are shown in Fig. 3. A honeycomb film isfabricated by casting a polymer solution (polystyrene +chloroform + surfactant). The polymer solution poured in a cellmade of PTFE is initially confined in a cell with electricalvalves as shown in Fig. 4. When the solenoid valve controller
having a G-sensor detects low gravity less than a threshold

References
1)

M. Shimomura, Nanocrystals Forming Mesoscopic Structures ed
M P Pileni (Weinheim: WILEY-VHC Verlag GmbH & Co.
KGaA): chapter 6 (2005) 157.

2)

H. Yabu and M. Shimomura, Chem. Mater.: 17 (2005) 5231-5234.

− J 57 −22A03

宇宙実験支援のための熱物性計測○ 勝田真登(1)，村上敬司 (1)，太田昌也(2),向井碧(2)，

Thermal Property Measurement for Support of Microgravity Experiment in JAXA
M. Katsuta(1), K. Murakami(1), M.Ohta(2) , M.Mukai(2)(1): JAXA (2):AES

Table 2 Specification of Wettability/Surface tension
Measurement Device

1. Introduction
Utilization of the space environment, especially utilization of
microgravity are greatly expected to be available to produce thenew or high-quality material which can’t be gotten on the
ground. On the other hand, it is clear that solidification andcrystallization of materials are affected by Marangoni flow or
wettability of container even they don’t matter on the ground.
In JAXA, we have developed the evaluation technology ofwettability since 1990[1]. And we have supported themicrogravity experiments by these evaluation technology on the
ground. These measurement data are opened to the public in
JAXA Web pages as opened data base[2].

Temperature range

Room temperature – 1500
degree C.

Temperature monitor

R-type(B-type) thermocouple

Atmosphere

Vacuum, Inactive gas and Low
concentration reducing gas

Pressure

0.01Pa – atmosphere pressure

Heating Method

Tungsten mesh heater

Vacuum pump

Dry pump and turbo molecular
pump

Image acquisition

Two axes CCD camera

Sample holdings

Static drop method, Extrusion
method

2. Experiment Support Systems
Table 1 shows our support system which can be used for
decision of the microgravity experimental condition. All systems
are set in Tsukuba Space Center. Especially, Wettability/Surface
tension Measurement Device (shown in Fig. 1) was developed
by JAXA. Its specification is shown in Table 2.
Table 1 Experiment support systems
No.

System1

Wettability / Surface tension
Measurement Device

Contact Angle, Surface
Tension2

Thermal Diffusivity
Measurement Device by
Laser Flash Method

Thermal diffusivity, SpecificHeat, Thermal Conductivity

3

High Temperature
Oscillating Viscometer

Coefficient of Viscosity

Measured Value

3. Support Results
Many measurement cases are related to experiments in ISS or
discussion in ground for ISS experiment. For Example, “Hicari”
Experiment which aims to make the high-quality SiGe
semiconductor crystal in microgravity received the support byour systems on ahead. The data which was measured by oursystem have served as a useful reference.
In addition to this, some themes which use the “GradientHeating Furnace (GHF)”, “Electrostatics Levitation Furnace(ELF)” or “Multi-purpose Small Payload Rack (MSPR)” were
supported as well as Hicari. Not only the crystal growthexperiment but also the combustion experiment is included inthese supported cases.

4. Future Prospects
Researchers which aim the ISS experiment can use our systems
for decision of the experiment condition on the ground. In
addition our data base can be the reference for many potential
users in the future. In these ways, the result of experiment in ISS
will be maximized.
References[1] Keiji MURAKAMI, Kenji MIKAMI and Yoshio
HAYASHI, Thermal Property Measurement System in
JAXA, 2007, J.Jpn Soc. Microgravity Appl.Vol.24 No.1
[2] http://idb.exst.jaxa.jp/db_data/property/ (Accessed Sep.
24th)

Fig.1 Wettability / Surface tension Measurement Device− J 58 −22A04

ジルコニア式酸素ポンプを用いた低酸素分圧下における金属高温融体の表面張力測定○小澤俊平（千葉工大），高橋優（首都大），武井悠翔（千葉工大），
渡辺直行（首都大），渡邊匡人（学習院大）

Surface Tension Measurement of High Temperature Molten Metal under
Low Oxygen Partial Pressure Atmosphere using Zirconia Oxygen Pump
1. Introduction

2. Experimental procedure
High purity nickel (provided from Dr. K. Tanaka, Sumitomo
Metal Mining Co., Ltd.) was electromagnetically levitated andthen melted under flow condition (2L/min) of Ar-He mixed gas.
The Po2 of the gas was maintained to 3.8×10-19 Pa by theoxygen pump (ULOCE-500, Canon Machinery Inc) operated at
873K. The oscillation behavior and the temperature of thedroplet were monitored from above using a high speed video
camera and a single color pyrometer. The surface tension ofmolten samples was calculated from the frequencies of m=0, ±1,
and ±2 for l=2 mode of the droplet using Rayleigh equation 2)
calibrated by Cummings and Blackburn 1).

Surface tension , 10-3N･m-1

2000

The ability to measure accurate surface tension of molten
metals is important for reliable numerical calculation of hightemperature melt processes such as welding and casting. One
such promising technique is the oscillating droplet techniqueusing electromagnetic levitation (EML). When this technique isemployed on the ground, theoretically-derived Cummings andBlackburn calibration 1) is required because the levitated droplet
is deformed from a spherical shape due to the gravitational
acceleration and magnetic force from a levitation coil. However
this calibration has not been confirmed by experimentcompletely. However this calibration has not been validated by
an experiment completely because the influence of the Po2 on
surface tension has not been considered in the experiment;
oxygen is strong surfactant for molten metals.
In order to validate the Cummings and Blackburn calibration
properly, a long microgravity experiment in consideration of theinfluence of the Po2 is expected at the International Space
Station (ISS). One possibility for the Po2 control at the ISS
experiment is to employ a zirconia oxygen pump.
A zirconia oxygen pump was used to control the oxygen
partial pressure of atmospheric gas during surface tension
measurement of molten nickel by oscillating droplet method
using EML on the ground. The purpose of this study was toinvestigate the effectiveness of the oxygen pump for the Po2
control in the surface tension measurement at the ISS.

1800

1700

1600

Without oxygen adsorption
Measured under Ar-He-5vol.%H2
Measured under Ar-He (Po2 was controlled to 3.8×10-19Pa
by oxygen pump at 873K)

1500
1400

1600

1800

2000

2200

Temperature T, K

Fig. 1

Surface tension of molten nickel measured under ArHe gas processed by oxygen pump and under Ar-He5vol.%H2 gas. The surface tension of pure state is
expected from the plots as a dashed line

flow condition of Ar-He gas processed by the oxygen pump.
Also shown is the surface tension of molten nickel measured
under the Ar-He-5vol.%H2 gas with the moisture content of 2.66ppm3). We successfully measured the surface tension of molten
nickel over the very wide temperature range of 750K including
undercooling conditions. The temperature dependence of thesurface tension of molten nickel exhibited a kink due tocompetition between the temperature dependence of the Po2 andthat of the oxygen adsorption equilibrium constant as in the caseof the surface tension measured under the Ar-He-5vol.%H2 gas.
The kink is observed at higher temperature under the gas
processed by the oxygen pump because of higher Po2. Even
though the Po2 is different between these experiments, almost
the same surface tension is observed at low temperature. This
result implies that the influence of dissociation of H2O should
be considered for accurate evaluation of the Po2 of atmosphericgas prepared by oxygen pump during surface tension
measurement.

References
1)

D. L. Cummings and D. A. Blackburn: J. Fluid Mechanics, 224,
(1991) 395.

2)

Lord Rayleigh: Proceedings of the Royal Society of London, 29(1879) 71.
S. Ozawa , S. Takahashi, N. Watanabe, and H. Fukuyama: Int. J.
Thermophysics. (2012) submitted.

3)

3. Results and Discussions

1900

Figure 1 shows surface tension of molten nickel under the− J 59 −22A05液滴振動法による高温融体熱物性計測○渡邉匡人，水野章敏(学習院大)，小澤俊平 (千葉工大)，日比谷孟俊(慶応大)，石川毅彦（JAXA）

Thermophysical Properties Measurement of High-Temperature Liquids by Oscillating Drop
Technique under Microgravity
Masahito WATANABE, Akitoshi MIZUNO (Gakushuin Univ.), Shumpei OZAWA(Inst. of Chiba Tech.),Taketoshi HIBIYA (Keio Univ.), Takehiko ISHIKAWA(JAXA)

Oscillating drop method with levitation technique under the
microgravity conditions has advantage of thermophysicalproperties
measurements
high-temperatureliquids.
Thermophysical properties of high-temperature melts areindispensable for numerical simulations of materials processing.
Accurate data are necessary to improve the process modeling,which leads to cost-effective production of high-quality
products. From the requirements the levitation technique, which
provides containerless conditions during the measurements, isprogressed for accurate measurements of the thermophysicalproperties of high-temperature liquids. Therefore, we areplanning thermophysical properties of high-temperature melts in
the International Space Station (ISS) 1,2) using the materialsscience laboratory-electromagnetic levitator (MSL-EML)3). On
this basis JAXA and ESA together with national space agencies
in Europe has set up a strong scientific collaboration
programmed to utilize space as a complementary crucial tool toease and accelerate the development of new products throughknowledge-based designs using the timely fundamental
advances acquired from in the near future, the ISS. Using
MSL-EML we obtain the surface tension from the surface
oscillation frequency and also the viscosity from the dumping
time of the surface oscillations under the microgravity
conditions. However, analysis of oscillating drop method in
EML must be improved even in the microgravity conditions,because on the EML conditions the electromagnetic force(EMF) cannot generate the surface oscillation with discretely
oscillation mode. Since under microgravity the levitated droplet
shape is completely spherical, the surface oscillation frequency
with different oscillation modes degenerates into the single
frequency. However, if sample position moves close to thecoils, droplet shape is modulated by the EMF even in small
electric current case. The droplet shape modulation changes theoscillation mode and then cause to the oscillation frequency
separation. Therefore, for our project purpose of precise surface
tension measurements under the controlled oxygen atmosphericconditions we must clarify the droplet shape modulation effects
on the surface oscillation frequency shifts. Because if oscillation
frequency is shifted by droplet shape modulation, we missunderstanding of how the oxygen atmospheric condition affects
on the surface tension. Moreover, for the viscosity
measurements we also care of the different oscillation mode by

the droplet shape modulations. Because dumping time of
surface oscillation of liquid droplets depends on the oscillation
modes, the case of surface oscillation including multi oscillation
modes the viscosity values obtained from dumping time will be
modified from the correct viscosity. Therefore, we investigate
the dumping time of surface oscillation of levitated dropletswith different oscillation modes and also with including multioscillation modes using electrostatic levitation (ESL) on groundand EML under microgravity conditions by the parabolic flightof airplane. The ESL can discretely generate the surface
oscillation with different oscillation modes by the change ofgeneration frequency of surface oscillation, so we can obtain
dumping time of surface oscillation with discrete oscillation
mode. We obtained the dumping time of surface oscillation withdifferent EMF conditions by EML under microgravity using
parabolic flight of airplane operated by Diamond Air Service 4).
The different EMF conditions generated the different surface
oscillations with multi oscillation modes. From both levitation
experiments, we obtained the different dumping time dependingon the external force conditions. From the precise analysis of
the dumping time difference, we discuss about that how does
the dumping time modification by the oscillation modeconditions affect on the viscosity values from the Rayleigh’s
relations 5). We also discuss the collection model of surface
oscillation dumping for the case of multi oscillation modes
generated in droplets. In the presentation, we also introduce thetask and future plan of this international collaboration projects.

Acknowledgments
This work was supported by JAXA-WG and also by JSPS
KAKENHI Grant Number 24360316.
References
1) H.-J. Fecht et al., Europhysicsnews, 39 (2008)19.
2) I. Egry and D. Voss, J. Jpn. Soc. Microgravity Appl., 27 (2010) 178.
3) W. Soellner et al., J. Jpn. Soc. Microgravity Appl., 27 (2010) 183.
4) S. Ozawa et al., J. Jpn. Soc. Microgravity Appl., 27 (2010) 215.
5) S. Ozawa et al., J. Appl. Phys. , 109 (2010) 014902.

− J 60 −