-
Hiroaki YANAGIDA
2000 Volume 12 Issue 3 Pages
153-156
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Brevity is the soul of future in technology. We have to avoid spaghetti syndromes of modern technology. For this purpose intelligent materials must be developed. Yanagida proposes ken-materilas to meet the requirement for the future technology. Authorities have to find novel concepts to make technology more easily understood to avoid unnecessary confusion. Integration is an important key word. Improvement of structural reliability and capability of self-damage monitoring may be achieved if we design so beforehand. This opens a new field of materials design in composite materials. Typical case is a concrete structure reinforced by CFGFRP (carbon fiber and glass fiber co-reinforced plastic) bars. This may be extended to diagnose damage of fragile materials such as ceramics used for heat engine component and concrete piles. R & D is conducted by Ken-materials Research Consortium led by Yanagida.
View full abstract
-
Hirohisa UCHIDA
2000 Volume 12 Issue 3 Pages
157-165
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
While each nation is attempting to strengthen its economy and international competitiveness, due consideration should be given to the harmony between people and the development of science & technology. This paper points out important factors to be considered in designing an
Environment
COnscious:
ECO-global society from a viewpoint of recent progress in materials science for energy and human environment.
View full abstract
-
Toshiharu FUKUNAGA
2000 Volume 12 Issue 3 Pages
166-174
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Mechanical alloying was employed to synthesize hydrogen storage graphite materials and cell materials as anodes of secondary lithium-ion batteries. First of all, the mechanical alloying of graphite was carried out under Ar gas atmosphere. Hexagonal graphite was used as a starting material. The transformation from the hexagonal graphite composed of layers into amorphous-like carbon was observed by using a highly resolved neutron diffraction technique. In case of the mechanical alloying under D
2 gas atmosphere, deuterium was absorbed by the solid-gas reaction. Two types of the location of deuterium atoms were found in
RDF(r). One is the C-D covalent bond and the other is due to deuterium located between layers of the graphite. Lithium-graphite intercalation compound was obtained by mechanical alloying of graphite and lithium mixed powders. The short range structure around a Li atom was observed by using the advantage of neutron diffraction. The coordination number of the C-Li correlation indicates the formation of LiC
3.1 intercalation compound.
View full abstract
-
Julien BROWAEYS, Cyrille FLAMENT, Jean-Claude BACRI, Lisa HOUILLOT
2000 Volume 12 Issue 3 Pages
175-177
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
We describe the concept of a voltage generator based on the use of a magnetic fluid. A cell contains two immiscible liquids: the lower liquid boils at a low temperature and the upper is a magnetic liquid magnetized by a permanent magnet. By heating the bottom of the cell the lower liquid boils and bubbles of the gas phase cross both liquid phases; consequently a flux variation is induced in a detection coil. Finally, the gas phase condenses in a recovery device in order to be injected back at the bottom of the cell. We obtain a voltage generator with a shape signal linked to the nucleation frequency and to the volume of the gas bubbles.
View full abstract
-
Kazuya OGURI, Sanshirou OGINO, Yoriyoshi UCHIKAWA, Yasuzumi OCHIAI, Yo ...
2000 Volume 12 Issue 3 Pages
178-179
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A variable reluctance hybrid magnet was studied to apply to a new type of high torque motor. The shaft torque at stillness is about 1000kgf·cm for a 20A current. The torque is about twice larger than that on the motor with no permanent magnet.
View full abstract
-
Kyoji TACHIKAWA
2000 Volume 12 Issue 3 Pages
180-184
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Superconductors with improved performance have been developed, which play a significant role in the progress of different scientific and technical fields, e.g. energy, environment, life science, communication, transportation, industrial processing as well as fundamental research.
View full abstract
-
Haru-Hisa UCHIDA, Shigeru OHGA
2000 Volume 12 Issue 3 Pages
185-188
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
In this paper the intelligence of Aluminum (Al) is considered with an experiment of Al recycling from used beverage cans, caps and foils. In the recycling of Al of used beverage cans, several processes can be considered. Using a new Al retrieving process, not only the enlarged yield rate, but also metal Al with lower impurity could be obtained. This may result in a decreased environmental impact, such as CO
2 emission, where the material may be defined as more intelligent from the environmental point of view.
View full abstract
-
Iwao HACHIYA, Tetsuo KOYANO
2000 Volume 12 Issue 3 Pages
189-193
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
To control and improve crystallization of Form V of cocoa butter, which is a main ingredient in the fat phase of chocolate, and fat bloom stability, we developed a new crystal seeding method using a crystal powder of the β
2 form of BOB (2-oleoyl-1, 3-dibehenoylglycerol). The BOB β
2 seeding can easily control the preferable polymorphic crystallization instead of a tempering process used in the chocolate industry. BOB β
2 has a triple chain length structure and subcell packing of T
//, which is same as Form V of cocoa butter. In addition, BOB β
2 does not melt at higher temperature than the melting point of chocolate because its melting point is 51.4°C. From this reason, the 5% seeding of BOB β
2 completely prevents the fat bloom formation on the surface of chocolate products even after heating at 38°C. The application of this method is practically used in the domestic chocolate industry.
View full abstract
-
Takehiro DAN, Mitsuru EGASHIRA, Junro KYONO, Hiroshi FUDOUZI, Mikihiko ...
2000 Volume 12 Issue 3 Pages
194-199
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The purposes of the present work are to describe the importance of forced electrification to particle hybridization and to develop new materials with multi-functions by combining two kinds of particles electrified reciprocally. This paper reports a preparation method and the positive temperature coefficient of resistivity (PTCR) properties of complex particles consisting of semiconductive BaTiO
3 particles and metallic indium particles by this method.
Moreover, it is thought that the electrical properties at contact interfaces between these two kinds of particles plays a very important role in the cell packed by these complex particles. In the next stage, these properties were measured quantitatively. As a result it was confirmed that the I-V characteristics at the contact interface between a semiconductive BaTiO
3 disc and vapor-deposited metallic indium film were similar to those at the contact interface between a semiconductive BaTiO
3 disc and liquid In-Ga eutectic alloy layer. But it was apparent that vapor-deposited Au film formed a Schottky barrier because of its high value of work function.
View full abstract
-
Shigeo KAWASAKI, Naoki OHKUBO
2000 Volume 12 Issue 3 Pages
200-205
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Applications of the novel artificial microwave crystal, PBG, made by etching were demonstrated for the circuit as well as for the antenna. The PBG was designed using a computer program based on the FDTD method. From observation of experimental data, the improvement of the microwave and millimeter-wave circuit and of the planar antenna by combining the PBG technique were confirmed.
View full abstract
-
Tadashi SHIRAISHI
2000 Volume 12 Issue 3 Pages
206-210
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
It is well known that the hydrogenated amorphous silicon (a-Si: H) prepared from SiH
4 gas in a UHV (ultra high vacuum) system nonessentially contains carbon(C) nitrogen (N) and oxygen (O) atoms of about 10
17, 10
16 and 10
18cm
-3, respectively. The electron negativity of C, N and O is 2.5, 3.0 and 3.5, respectively and these values are larger than that of Si, 1.8 and H, 2.1. Therefor, it is expected that the created Si
+-O
---H
+, Si
+-O
---Si
+ and Si
+-H
- bond behave as like as ionic like bond. If a negatively (or positively) charged Si atom, T
3- (or T
3+) exists vicinity of the H
+ (or H
-), the H
+ (or H
-) forms hydrogen bond with the T
3- (or T
3+). The density of dangling bonds T
3 defects is 10
14N-10
15cm
-3 in a-Si: H. These ionic like bond and hydrogen-bond make electric dipoles and that creates electronic potential and may act like as a carrier trap, a recombination center and scattering center which strongly affect carrier mobility. In this paper, especially we will discuss a trapping effect due to the ionic like bond and hydrogen bond which is with an isomerization effect of Si
+-O
---Si
+ and Si
+-O
---H
+ configurations.
View full abstract
-
Kohji MITSUBAYASHI, Yuki HASHIMOTO, Yoshihiro NAKAYAMA, Thierry MONTES ...
2000 Volume 12 Issue 3 Pages
211-216
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Gas-phase biosensors were constructed using a unique reaction cell with both gas and liquid phase compartments separated by a diaphragm membrane and an immobilized enzyme electrode with alcohol oxidase, aldehyde dehydrogenase and flavin-containing monooxygenase for measurement of ethanol, acetaldehyde and trimethylamine, respectively. The gas sensors possessed high selectivity for their analyte vapor in the presence of other gas phase chemicals and gave a negligible response to these chemicals.
View full abstract
-
Thierry MONTESINOS, Sandra PEREZ-MUNGUIA, Jean-Louis MARTY, Kohji MITS ...
2000 Volume 12 Issue 3 Pages
217-222
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A disposable cholinesterase biosensor based on screen-printed electrodes (SPE) was assembled and used to assess the effect of miscible organic solvents on the acetylcholinesterase activity and on the inhibitory effect of organophosphorus pesticides on acetylcholinesterase activity. Acetonitrile, ethanol and DMSO were tested in a range of 0 to 30% mixed with phosphate buffer (0.1M, pH7). With 5% acetonitrile and 10% ethanol, an increase of the recorded current was observed. The addition of 0.2% polyethylenimine to the enzyme preparation, before immobilization, allowed the utilization of 15% acetonitrile without negative effect on the enzyme activity. An inhibition calibration curve was obtained using chlorpyrifosethyl-oxon, a compound widely used for agricultural purposes. The lowest detectable amount was 1ppb following an incubation time of 10min. The use of 5% acetonitrile and 0.2% polyethylenimine did not interfere with the enzyme-inhibitors interactions. The second part is focused on the evaluation of the activity of several genetically modified acetylcholinesterases obtained from
Drosophila melanogaster and their inhibition constant face to the methamediphos. The selection of one of them and its immobilization on a SPE allowed a detection of 1.4ppb methamediphos.
View full abstract
-
Ken NAITOH
2000 Volume 12 Issue 3 Pages
223-230
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A mesoscopic kinetic theory is proposed, which describes synthetically the atomizations of flexible liquid droplets, the biological cell divisions, and the unlacing processes of biological molecules such as DNA and RNA surrounded with water molecules, that is, the chemical reaction processes related to the hydrogen bonds. The present theory clarifies the reason why the ladder of asymmetry related to the artistic ratios of about 2:3, such as the golden and silver ratios, are observed in the size and density of liquid droplets, biological cells, and nitrogenous bases such as adenine and thymine. Finally, the origin of nucleotides and transfer RNA (tRNA) molecules, that is, the origin of information and function, is clarified on the basis of the present theory.
View full abstract
-
T. MARIMBORDES, A. OULD EL MOCTAR, H. PEERHOSSAINI
2000 Volume 12 Issue 3 Pages
231-237
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A two dimensional cavity filled with a fluid subjected to ohmic heating is studied. A linear stability analysis including the control strategy is developed. The feed-back control strategy using the derivation of the real temperature from that of the associated conductive state is applied for this purpose
View full abstract
-
Mami TANAKA, Hideki ICHINOSE, Seiji CHONAN, Katsuko NUMAGAMI, Zhong We ...
2000 Volume 12 Issue 3 Pages
238-243
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
This paper is concerned with the development of a haptic sensor system that monitors the human skin conditions. The base of the sensor is an aluminum shell, around which a sponge rubber layer, a PVDF film, a protective acetate film and a gauze are stacked in sequence. The sensor is attached onto the tip of an elastic cantilevered beam and pressed against the human skin. It is then moved by hand over the skin to collect the surface morphological features through the sensor. The characteristics of data are extracted by calculating the variance and the distribution of power intensity over several segmented frequency ranges. Each set of data obtained is used as a training set of data for a neural network that distinguishes the skin with atopic dermatitis from the normal healthy skins. Experimental results show that 100% of recognition is achieved by using the constructed network system.
View full abstract
-
What is “Intelligent Materials”?
Yoshitake Nishi, John S. Brodie
2000 Volume 12 Issue 3 Pages
244-251
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Materials are, by definition, substances that are used. It follows that utility (U
m) is also an essential factor in evaluating intelligent materials. The U
m value reflects the degree of development of the material. Developing original concepts for ideal intelligent materials calls for bold, imaginative and broad based thinking. This paper proposes guidelines for the evaluation of materials intelligence (I
h) by analogy with human intelligence functions. Taking into consideration of the I
h and U
m values, we also define and evaluate a potential (μ
h) of intelligent materials. Furthermore, we suggest an impact intelligence (I
i) and an impact potential (μ
i) for materials from the point of view of future industrial impact. The premise of the paper is that the concept of intelligent materials will be one of the dominant factors in breakthrough technologies of the future.
View full abstract
-
G. Bossis, C. Métayer, S. Lacis, C. Abbo
2000 Volume 12 Issue 3 Pages
252-256
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Electroactive elastomers are composites made of solid particles embedded in an elastomeric network whose electrical, mechanical or optical properties can be changed by the application of an electric or a magnetic field. These materials have obviously a strong connection with ER and MR fluids and can be more appropriated for some applications. We present results concerning the conductivity, magnetic permeability and elasticity of an elastomer filled with iron or carbonyl iron particles. We show that the change of elastic properties obtained by the application of a magnetic field depends strongly on the gap between the particles. We explain quantitatively the experimental results with the help of finite element calculation to predict the magnetic forces between the particles. The effect of a magnetic field on the electrical resistance is also investigated and we show that we can obtain a huge decrease of the resistance by the application of a magnetic field.
View full abstract
-
Towards tailored surface topographies
Patrick BOURGIN, M'hamed BOUTAOUS
2000 Volume 12 Issue 3 Pages
257-261
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Surface roughness plays an important role in the stress state generated within a roll of a flexible material (i.e. plastic film). In can be appreciated in an indirect way through the Young's modulus of the roll in the radial direction. A theoretical model confirms the importance of this modulus. An experimental device allows to test the behavior of a single layer of film submitted to compression, and some “dynamic roughness coefficient” is introduced. The link between this coefficient and (1) some adequate (static) description of the surface topography and (2) the behavior of a stack of film layers is to be established.
View full abstract
-
Hiroshi ASANUMA
2000 Volume 12 Issue 3 Pages
262-267
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
This paper describes a basic concept and elemental developments to realize a new actuator made of active composite material to be used for smart structures. In this study, CFRP prepreg was laminated on aluminum plate to develop an actuator and this laminate could perform unidirectional actuation. SiC continuous fiber/Al composite thin plate could also be used to form a modified type of actuator instead of using CFRP. As sensors to be embedded in this actuator, the following ones were developed. (1) A pre-notched optical fiber filament was embedded in matrix material without fracture and fractured in it at the notch, which enabled forming of an optical interference type strain sensor. (2) Nickel wire could be uniformly oxidized and embedded in aluminum matrix without fracture, which could successfully work as a temperature sensor and a strain sensor.
View full abstract
-
Philippe GUY, Thomas MONNIER, Jean-Claude BABOUX, Michèle SALVI ...
2000 Volume 12 Issue 3 Pages
268-274
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The health of a structure depends on both the homogeneously distributed degradation of its mechanical properties during its life cycle and the presence of localised defects such as cracks or delaminations. The proposed non-destructive health monitoring method allows recovering both kinds of information using ultrasonic waves. To avoid traditional techniques limitations, such as coupling reproducibility for instance, we propose here to integrate a piezoelectric element into the plate-like composite structure. The element dimensions are determined in order to uncouple the frequency ranges of the thickness and radial vibration modes. The thickness mode is used to monitor the homogeneous ageing of the structure through electrical impedance measurement. As for the radial vibrations, they are used to generate and detect Lamb waves, which have the advantage of propagating over long distances and offering specific sensitivity of various modes to different kinds of defects. The present work focuses on this last application and studies the ability of the proposed technique to detect and identify defects such as low speed impact-induced delaminations and cracks in composite plate-like structures.
View full abstract
-
Hideaki MATSUBARA, Yoshiki OKUHARA, Hiroaki YANAGIDA
2000 Volume 12 Issue 3 Pages
275-280
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The electrically conductive fiber reinforced plastics (FRP) and ceramics matrix composites (CMC) have been designed and fabricated in order to introduce the self-diagnosis function in these materials. The electrical conductivity was achieved by adding conductive particles into the matrices of these composites. The FRP with percolation structure consisting of carbon particles had liner response of resistance to the tensile strain and high sensitivity in the wide strain range. The FRP embedded in mortar block successfully diagnosed micro-crack formation and propagation, showing that the self-diagnosis function of the FRP has the ability to monitor the health condition of concrete structures. The CMC materials containing TiN particles as a conductive phase indicated not only fine response of resistance to the applied strain but also resistance increase with increasing number of repetitions during cyclic bending test. These results suggest that these composites can be brought to many industrial applications concerning the self-diagnosis of deformation and damage in structural materials.
View full abstract
-
Hisaaki TOBUSHI, Kayo OKUMURA, Masato ENDO, Shunichi HAYASHI
2000 Volume 12 Issue 3 Pages
281-286
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The thermomechanical properties of polyurethane-shape memory polymer foam were investigated by the compressive tests. The results are summarized as follows. (1) The material contracts uniformly in the axial direction with the ratio of lateral strain to axial strain 0.4 in the early stage but about 0.15 thereafter. (2) The deformation resistance is large at low temperature and at high strain rate. (3) In the case of thermomechanical loading, strain is recovered at temperatures in the vicinity of
Tg. The rate of strain recovery is 99%. The rate of strain fixity is 100%.
View full abstract
-
Taras PELEKH, Jun-ichi MATSUSHITA
2000 Volume 12 Issue 3 Pages
287-290
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The process of heat transfer at solid body is considered during high temperature oxidation. The temperature redistribution in solid body leads to occurrence of the new phases, which are favorable to increasing of mechanical characteristics of hard alloy WC-Co.
View full abstract
-
Emmanuel Chailleux, Michelle Salvia, Nicole Jaffrezic-Renault, Yves Ja ...
2000 Volume 12 Issue 3 Pages
291-297
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
This paper reports on a comparative study carried out for different type of sensors which are able to monitor in-situ curing of thermosets resin. In fact, the thermoset matrix composites are increasingly used as structural parts in complex technological structures. So, monitoring the matrix microstructural evolution and the development of internal stresses during the cure is now of the utmost importance. Taking in account their inhomogeneous structures and processing methods, mesoscopic sized sensors may be embedded into the composite materials. Until now different characterisation techniques have been applied independently in order to monitor essentially the cure process:
-Frequency dependant dielectric measurements provide a sensitive in situ sensor able to give access to the electrical conductivity and complex permitivity of the surrounding medium. The conductivity parameter related to the ionic mobility is linked to the polymerisation advancement
-The ultrasonic waves are generally used for global characterisation of mechanical properties. For in situ applications, a piezoelectric element is embedded in the structure during its processing and the rheological properties of such a material-system can be monitored.
-Refractive index measurement is carried out with a fibre-optic sensor. This optical parameter allows to determine the density of the thermoset resin during the cure process and to access to the extent of cure.
The multidetection measurement seems to be a powerful tool to understand the chemorheological mechanisms occurring during the thermosets resin cure process.
View full abstract
-
Hideaki MURAYAMA, Kazuro KAGEYAMA, Isao KIMPARA, Akiyoshi SHIMADA, Hir ...
2000 Volume 12 Issue 3 Pages
298-302
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Health monitoring technologies of a structure made of polymer matrix composites have lately become a subject of special interest. International America's Cup Class (IACC) yachts are specific boats whose most components made of carbon fiber reinforced plastic (CFRP) and that are regulated by the IACC rule. A Brillouin optical time domain reflectometer (BOTDR) is a fiber optic distributed sensor that can measure strain and temperature along an optical fiber. We equipped IACC yachts that were the Japanese entry in America's Cup 2000 with these sensors. Strain distributions of the yachts measured with BOTDR were used for structural health monitoring and assessments of the structural integrity were continued during races.
View full abstract
-
Tae-Young UM, Yoshimasa KOBAYASHI, Jinhao QIU, Junji TANI, Hirofumi TA ...
2000 Volume 12 Issue 3 Pages
303-308
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The present study aims to improve the capacity of actuator materials by focussing on the properties of a single sheet. Thin Pb(Zr
0.53Ti
0.47)O
3 and Pb(Nb
2/3Ni
1/3)
0.55(Zr
0.3Ti
0.7)
0.45O
3 composition sheets (about 130μm in thickness) with large surface areas were fabricated and their properties were investigated. Green sheets with uniform thickness distribution were fabricated by the doctor blade with a slurry viscosity of 2000-5000cp. Additives such as solvent, binder, plasticizer and dispersant were completely eliminated by the heat treatment which was carried out at 500°C. The PbO excess atmosphere sintering at temperatures above 1050°C and 1200°C produced high density Pb(Zr
0.53Ti
0.47)O
3 sheets with only perovskite phases, and Pb(Nb
2/3Ni
1/3)
0.55 (Zr
0.3Ti
0.7)
0.45O
3 sheets with perovskite phases and traces of pyrochlore phase, respectively. The dielectric and piezoelectric properties of sintered sheets showed slightly lower values than those of bulk samples fabricated by typical powder processing; however, the sheets exhibited a relatively large displacement at low electric fields.
View full abstract
-
Martine LEJEUNE, Sylvie KURUTCHARRY, Maksoud OUDJEDI, Pierre ABELARD
2000 Volume 12 Issue 3 Pages
309-315
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The electromechanical responses of 0.9PMN-0.1PT ceramics are reported in different conditions, i.e. under variable electric field (static or dynamic), compressive stress and temperature. The resulting strain characteristics are well fitted in terms of an hyperbolic tangent formulation. The apparent elastic compliance and piezoelectric coefficient, deduced from this expression, are strongly dependent on the different environmental parameters (electric field, compressive stress and temperature), which underlines the adaptive behavior of 0.9PMN-0.1PT ceramics. This one results from the sensitivity of the nanostructure of these ceramics, corresponding to the development of compliant polar domains with increasing electric field, decreasing compressive stress and temperature. Moreover, the adaptive character of 0.9PMN-0.1PT ceramics is essential in regards to development of intelligent structures with numerous applications in different fields (automotive, aeronautic, medical, home automation, ..). In particular, the potentialities of this material for active damping applications is introduced, and other promising routes to integrate 0.9PMN-0.1PT material in intelligent structures are suggested.
View full abstract
-
Takashi IIJIMA, Bo-Ping Zhang, Norio SANADA, Kouki KUNII
2000 Volume 12 Issue 3 Pages
316-319
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A diaphragm type (100) dominant oriented tetragonal phase lead zirconate titanate (PZT) film actuator is fabricated to achieve the micro actuators and acoustic transducers system. The ferroelectric properties of the texture controlled PZT film is relatively good compared with other reported data and is comparable to those of bulk PZT ceramics. The displacement of the PZT film actuator driven at ±20 V shows a butterfly like hysteresis. However, this butterfly shape shows opposite direction compared with the typical displacement curve of bulk PZT ceramics. This depressed displacement property of the PZT film appears to indicate bend motion in the vertical direction on the film surface since the film is not clamped, and it does not reflect the genuine piezoelectric property. The value of the maximum displacement is about 160nm. It can be seen that the texture controlled PZT films is applicable to the film micro actuator and transducer.
View full abstract
-
Keiji KUSUMOTO, Yoshiro SHIMOJO, Tadashi SEKIYA
2000 Volume 12 Issue 3 Pages
320-325
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Relaxor-type ferroelectric perovskite Pb(Ni
1/3Nb
2/3)O
3 (PNN) could be synthesized through a two-steps process consisting of heat treatment at high temperatures and then acetic acid treatment of oxide mixture containing PbO in amount greater than in the perovskite composition, though until now it is very difficult to obtain its single phase. This made possible to open a new route of actuator materials in the combination of PNN and other kinds of perovskite compounds. In this paper, an investigation was undertaken for the combinations with perovskites PbTiO
3 (PT), PbZrO
3 (PZ) and Pb(Sc
1/2Nb
1/2)O
3 (PSN), such as PNN-PT, PNN-PZ-PT, PNN-PSN and PNN-PSN-PT, to search compositions giving higher electric field-induced strain. In order to obtain higher strain, it was essential to bring close the composition near the morphotropic phase boundary (MPB) from rhombohedral to tetragonal symmetry. For the PNN-based ceramics showing higher strain, the potentiality as actuator was discussed.
View full abstract
-
Joël ABADIE, Nicolas CHAILLET, Christian LEXCELLENT
2000 Volume 12 Issue 3 Pages
326-331
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Microtechnologies and microsystems engineering use new active materials for microactuators and microsensors. In this field, Shape Memory Alloys (SMA) are good candidates for microactuation. They can actuate microrobots and are able to provide very important forces, but have low dynamic response, especially for cooling. Joule effect is an easy and classical way to heat the SMA actuators, but cooling is not so easy. Dynamic response of the actuator depends on cooling capabilities. This paper describes a reversible way for heating and cooling SMA microactuators, based on the Peltier effect. Using Peltier effect, a positive or a negative electrical current is able to absorb or produce heat in the SMA actuator. The integrated SMA microactuator presented here in the millimeter size. It consists of a thin blade of SMA working in flexion and placed in junction with a material with high thermoelectric features. This material is Bi
2 Te
3, i.e. bismuth telluride, N an P doped. As far as we know, it is one of the first investigations with a real measurement of the motion of the SMA actuator using integrated thermoelectric junctions. Using this system, we are able to control the temperature of the SMA blade in a range of -10°C to 90°C. Some experimental results are given.
View full abstract
-
Yasubumi FURUYA
2000 Volume 12 Issue 3 Pages
332-336
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Electro-magnetic melt-spinning method is applied for developing higher performance shape memory actuator/sensor materials. The obtained characteristic metallurgical microstructure is discussed from crystal anisotropy and grain boundary interface morphology. Our recent developments of new types of shape memory alloys of rapid-solidified TiNi systems having the capabilities of larger and faster actuation and magnetically induced ferromagnetic shape memory actuator Fe-Pd alloy system are introduced. The several potential applications by unique features of SMAS are also proposed.
View full abstract
-
Toshiyuki TAKAGI, Yun LUO, Shinya HARA, Tomoyuki YAMABE, Shintaro AMAE ...
2000 Volume 12 Issue 3 Pages
337-342
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
This paper describes the development of an artificial sphincter using shape memory alloy (SMA). With the artificial sphincter it is expected to enable the active bowel movement of patients with the lack of anal sphincters due to inborn intestinal atresia or medical operations of an artificial anus. The SMA actuator has the function of a sphincter muscle; keeping the artificial anus closed at the body temperature and opening it by heating. Investigations on the thermomechanical properties of the actuator have been carried out. Animal experiments have also been done, and the results showed potentially applicability of the artificial sphincter for implantation in living bodies.
View full abstract
-
Hiromasa YABE, Kazuya OGURI, Haru-Hisa UCHIDA, Yoshihito MATSUMURA, Hi ...
2000 Volume 12 Issue 3 Pages
343-344
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Top data of magnetostrictive susceptibility was obtained at Fe-45at%Pd film. The reversible relationship was obtained between shape change and applied magnetic field from earth magnetic field to 0.2 kOe. The high magnetostrictive susceptibility at room temperature was higher than that of Tb
0.3Dy
0.7Fe
2 thin film developed.
View full abstract
-
Kazuhiro SHIGENOBU, Kazuhito SUGANUMA, Yoshitake NISHI
2000 Volume 12 Issue 3 Pages
345-346
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Fish freshness should be maintained by effect of tourmaline on water pH since the fish freshness is evaluated by concentrations of ATP related substances, which decompositions are controlled by the tourmaline. The tourmaline treatment maintains fish freshness for approximately 2 days longer.
View full abstract
-
Yuka OZU, Ryota GENMA, Haru-Hisa UCHIDA, Shigeru OHGA, Makoto OHGA
2000 Volume 12 Issue 3 Pages
347-349
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Since several years we have proposed and practically used a unique process, which retrieving metallic Al from used beverage cans, caps and other Al-organic composite materials
1. This recycling process is characterized by the treatment without any melting, which saves a pretty amount of energy. In this process decorative coating containing metal oxide is detached as powder by mechanical process, which results in the higher purity of Al. The rest powder is only the waste yielded throughout this process. In this paper the waste of this detached paint powder was tested its possibility of photo-catalytic application because a large amount of TiO
2 was contained. Certain photo-catalytic effect was confirmed on sintered waste paint powder by irradiation of ultra violet light. The waste may be used as construction materials with photo-catalytic function.
View full abstract
-
Yoichi ISHIMOTO, Fumie NAKAJIMA, Taras PELEKH, Jun-ichi MATSUSHITA
2000 Volume 12 Issue 3 Pages
350-351
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
In the forest or near the waterfall, people feel refreshing or so good. Recently, a part of scientist tries to solve the fact. As one theory, this matter is caused by a minus ion. It is said that minus ion is made by garnet system ceramics as used jewel. Then if the Garnet is mixed with paint or wall materials, people will be able to lead in comfort. And we experiment ammonia gas adsorption characteristic of garnet system ceramics for us to get the bottom of the fact.
View full abstract
-
Rie FUJII, Kazuya OGURI, Masaki TETSUKA, Akira TONEGAWA, Kazuo TAKAYAM ...
2000 Volume 12 Issue 3 Pages
352-354
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
Sheet electron beam irradiation [SEBI] decreased the time to clear vision of the TiO
2 surface. Decay of the effect was also studied. The effective period is about one hour.
View full abstract
-
Yoshihisa YASUOKA, Shigeo KAWASAKI
2000 Volume 12 Issue 3 Pages
355-358
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
One of the radar functions for the active integrated antenna array for beam steering utilizing harmonic injection into an MMIC oscillator is described in this paper. The fabricated 2×2 active integrated antenna array was locked by an external signal at frequency one half with respect to the fundamental operating frequency of the MMIC oscillator. Its beam steering operation was also confirmed by changing the frequency of the injection signal. A 10 degree beam variation was observed within the injection locking range of 3.90MHz. From these results, the fundamental data for realization of the millimeter-wave radar systems using the MMIC with low-cost and simple structure were obtained.
View full abstract
-
Kenichi USHIJIMA, Jun-ichi MATSUSHITA, Koichi KITAZONO, Eiichi SATO, K ...
2000 Volume 12 Issue 3 Pages
359-360
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
A composite consisting of Al matrix and giant magnetostriction particles was fabricated by powder metallurgy. The composite was heat treated under a magnetic field, where the particles induced giant magnetostriction, and after turning off the magnetic field at room temperature, the matrix possessed compressive residual stress. Tensile tests revealed that the above magnetization heat treatment improved the yield strength of the composite. The result proposed the new magnetostriction strengthening mechanism.
View full abstract
-
Samon TANAKA, Noriyuki FUKUSHIMA, Taras PELEKH, Jun-ichi MATSUSHITA
2000 Volume 12 Issue 3 Pages
361-362
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The oxidation behavior of GdB
6 in the temperature range of 873 to 1273K was investigated to determine the oxidation parameters for sintering the GdB
6. The derivatographical analysis of GdB
6 and X-ray diffraction analysis of oxidized GdB
6 were generated.
View full abstract
-
Noriyuki FUKUSHIMA, Takenori GOMI, Samon TANAKA, Jun-ichi MATSUSHITA
2000 Volume 12 Issue 3 Pages
363-364
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
In this study, SiB
6 and SiB
6-10wt%C prepared by hot pressing. The influence of temperature on the electrical conductivity of SiB
6 and SiB
6-10wt%C sintered body was investigated. The sample was sintered at 1973K for 3.6ks in vacuum under a pressure of 25MPa. The relative density of sintered body at 1373K was approximately 99%. The high temperature electrical conductivity measured using a D.C. four-terminal method.
View full abstract
-
Jun-ichi MATSUSHITA, Takashi KUBOTA, Yoichi ISHIMOTO, Taras PELEKH, Sh ...
2000 Volume 12 Issue 3 Pages
365-366
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The ceramic foam were prepared by silicon, sodium hydroxide and sodium fluoride. The influence of temperature on volume and weight change was investigated between 423K and 973K. The volume swelling rate of the sample increased with increasing temperature. The value of maximum volume swelling sample was 1382% at 773K for 10 to 20min.
View full abstract
-
Takanori NAKAMURA, Kazuya OGURI, Yoshitake NISHI
2000 Volume 12 Issue 3 Pages
367-368
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
The fracture toughness, indicated by fracture load (P
fmid) of quasicrystal reinforced Al-Li-Cu alloy, can be largely controlled by heat treatment at 553K. Furthermore, supersonic heat treatment shortens the aging time and enhances the fracture toughness.
View full abstract
-
Naotada HAGIWARA, Hiromasa YABE, Kazuya OGURI, Takashi ASAKA, Tsunenor ...
2000 Volume 12 Issue 3 Pages
369-370
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
In order to develop new shape memory materials operated by temperature, magnetic field, electrical current and pressure, the shape memory effect of the high T
c YBa
2Cu
3O
7-y superconductor was studied at different preparation methods using thermal expansion on softening. The sintering YBa
2Cu
3O
7-y with 30 mass% Ag has a prominent shape memory effect.
View full abstract
-
Kentaro TAKASHINA, Takanobu MATUMURA, Masaki TETSUKA, Yasuyuki MIYAZAW ...
2000 Volume 12 Issue 3 Pages
371-373
Published: January 31, 2001
Released on J-STAGE: February 25, 2010
JOURNAL
FREE ACCESS
To develop the high temperature shape memory bi-ceramics, the thermal expansion test was performed for Si-C-O glassy tyranno fiber which shows high resistant to heat and oxygen. The reversible shape change can be observed for Si-C-O glassy fiber sample under 1573K and below 25MPa.
View full abstract