# Fileset [kakenhi-1997-en-141-280.xlsx](https://mdr.nims.go.jp/filesets/c2805d09-06ee-4ee7-b579-a8f716580c53/download) ## Creator National Institute for Materials Science ## Rights In Copyright[In Copyright](http://rightsstatements.org/vocab/InC/1.0/) ## Other metadata [Physics and Chemistry of Functionally Graded Materials 　Research Report 1997　Grant-in-Aid for Scientific Research on PriorityArea, No. 274 　The Ministry of Education, Science, Sports and Culture of Japan (pp.141-280)](https://mdr.nims.go.jp/datasets/8889edb6-8d07-4a7f-8c89-942ac3bfce37) ## Fulltext Sheet1 BookTitle_j BookTitle_e Volume/Issue Issueddate Page Title_j Title_e AuthorList_j AuthorList_e Abstract Language Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 141-144 複合積層化合物を利用したナノスケール磁気傾斜機能材料の開発と物性 Preparation and Properties of Nano-scale Magnetically Graded Materials using Composite Layer Compounds 鈴木和也、道岡千城横浜国立大学　大学院工学研究科 Kazuya Suzuki and Chishiro MichiokaGraduate School of Engineering, Yokohama National University If some kind of function can work even in atomic layer scale we can easily design ultimately thin functional films or materials in which the function is graded in the atomic scale. We choose the layer compound (MS)x(TS2)n that has alternate stacking structure of MS and TS2 in order to study the fundamental properties of functional atomic layer. Incommensurate misfit layer compounds (MX)x(TX2)n (M=rare earth metal, Pb, Sn, Bi, T=Ti, V, Cr, Nb, Ta, X=S, Se, x=1.08- 1.25 and n=1,2) are now well known low dimensional electronic systems in which the structure consists of alternate stacking of hexagonal transition metal dichalcogenides (TX2) layers and tetragonal metal monochalcogenide (MX) bi-layers. (MX)x(TX2)n shows the "staging" structure denoted by a stage index n. In the case n=2, there exist the Van der Waals gaps between the adjacent TX 2 layers and one can intercalate some kinds of atoms or molecules in the TX2 interlayer. This indicates the possibility to yield highly designed magnetic materials by intercalation magnetic species. We have studied the synthesis and properties of Fe intercalated (MS)1.19(TiS2)2 in the passed year, and found that in (CeS)1.19 [Fe0.33(TiS2)2] magnetic order of Ce and intercalated Fe both developed in the different temperature, antiferromagnetic for Ce and ferromagnetic for Fe, respectively. In this report, we focused on novel compounds (MS)1.20CrS 2 and (MS)x[Fe0.33(NbS2)2] (M=La,Ce). The former compounds consist of magnetic Cr atoms in triangle arrangements in the crystal. The interatomic distances of Cr and M are much shorter than that of Fe-M in (MS)1.19[Fe0.33(TiS2)2] so that significant magnetic interaction is expected between the magnetic moments. In the latter compounds it is expected that the antiferromagnetic interaction works among Fe atoms that form triangle arrangement within the layer. The magnetic moments align in the stacking direction so that the very strong frustration may be possible to appear. We have investigated synthesis and electrical, magnetic and thermal properties of these compounds. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 145-148 DCアークプラズマ法による強磁性鉄窒化物膜の傾斜設計 Graded Design of Ferromagnetic Iron Nitride Film by DC Arc Plasma Method 山本直一冨井洋一花田禎一京都大学　大学院　人間・環境学研究科京都大学　大学院　エネルギー科学研究科 京都大学　総合人間学部 Naoichi YAMAMOTO, Youichi TOMII, Teiichi HANADADepartment of Human and Environmental Studies, Graduate School of Kyoto University Department of Fundamental Energy Science, Faculty of Energy Science. Graduate School of Kyoto University Department of Integrated Human Studies, Kyoto University Phase diagram (by R.H.Jack) shows three kind of iron nitride compounds exist at room temperature as stable phases, that is gamma' -Fe4N, epsilon-FexN (20) and antiferromagnetic (J<0) exchange interactions. Moreover, in a mixed ferro-ferrimagnet (Fe0.40Mn0.60)1 .5[Cr III (CN)6]*7.5H2O powder, we have succeeded in demonstrating a novel photo-induced magnetic pole inversion. In the present work, in order to study the magnetic properties of the novel types of magnetic thin films composed of a gradient composition between ferromagnetic and ferrimagnetic components along growth direction, we have prepared the new classes of magnetic thin films composed of mixed ferro-ferrimagnets, (Fe II xCr II 1-x)1.5[Cr III (CN)6]*zetaH2O, by a simple electrochemical method. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 165-168 低次元蛍光体の傾斜機能の研究 Study on graded function of low-dimensionaI phosphor 遠藤忠東北大学　大学院工学研究科　980-8579 宮城県仙台市青葉区荒巻青葉 Tadashi EndoGraduate school of Engineering, Tohoku University, Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan The self-activated luminescence of ZnGa2O4 with spinel structure has been studied. Recently, we found that ZnGa2O4 solid solution exhibited a full colored (white-emitting) phosphor if the solid solution consisted of the suitable graded compositions. The change in luminescence color was due to the change in emitting photon energy of donor-acceptor recombination center. The photon energy depended upon the bandgap which was determined from the absorption edges of solid solution. Also, the thermoluminescence (TL) occurred at the activated ions, giving rise to the luminescence characteristic of transition metal ion such as Mn2+ and Cr3+. The spinel structure consists of a f.c.c. anion sublattice that has half its octahedral interstices and one-eight of its tetrahedral interstices occupied by cations. Therefore the site preference of replaceable cation was governed luminescence characteristics. Simulataneously the decay profile of luminescence was changed by the partial replacement of aliovalent cation. Additional change, i,e. the formation of vacansies was needed to preserve electroneutrality. The present study was focused to identify the experimental parameters which was required to make the full-colored or white-emission of ZnGa2O4 phosphor with graded and non-stoichiometric composition. Also, the improvement of thermoluminescence of ZnGa2O4 relatives was examined on the viewpoint of cystallo-graphical low-dimensionality. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 169-172 キャリア濃度傾斜熱電半導体単結晶の熱電特性の研究 Studies on thermoelectric properties for thermoeleotric semioonducting single crystals with FGM structure 海部宏昌東京都立大学　大学院 工学研究科　電気工学専攻　192-03 東京都八王子市南大沢1-1 H. T. KaibeGraduate School of Engineering, Graduate Course of Electrical Engineering, Tokyo Metropolitan University, 1-1 , Minami-Ohsawa, Hachioji-shi,Tokyo, 192-03, Japan The possibility of improvement in thermoelectric performance for n-type PbTe with graded carrier concentration has been investigated since 1996. The hot-pressed compact with three-stage structure was prepared through piling up starting powder with different amount of dopant material. The 3-stages FGM had 10% larger output power than that of each constituent. And also, the liquid phase diffusion bonding technique, which is available for the solidified PbTe, has been established. However, the single crystal of the thermoelectric materials, such as Bi2Te3 and PbTe has not been obtained yet in this project. Then, the sublimation method was applied in order to grow the single crystals of n-type PbTe. The crystal grown from gas phase has superior crystalline to that of from melt phase. The improvement of the crystalline results in the elevation of the thermoelectric performance due to the increase in the carrier mobility. The sublimation method is also useful to fabricate FGM thermoelements with a graded carrier concentration by changing the starting material. Generally, the chemical transport technique which is one of the method of crystal growth from gas phase uses halogen compounds as agent material. In case of PbTe, halogen compounds such as PbI2 and SbI3 act as donor. Then, those compounds has roles for both agent and dopant. The knowledge concerning such as the growth direction and growth mechanism is considered to be strongly useful for the joining the dissimilar materials. In 1997, we have tried to fabricate p-type PbSnTe thermoelement with FGM structure. Then, materials parameters such as resistivity rho, thermoelectric power alpha and thermal conductivity kappa for p-type solidified PbSnTe were investigated. Furthermore, the liquid phase diffusion bonding usin insert metal was applied to join Pb0.75Sn0.25Te and Pb0.5Sn0.5Te. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 173-176 傾斜機能CuInSe薄膜太陽電池 Functionally Graded CulnSe2 Thin Fillm Solar Cells 伊藤太一郎、小見崇、伊崎昌伸＊、芦田淳大阪府立大学　　＊大阪市立工業研究所 Taichiro Ito, Takashi Omi, Masanobu Izaki * and Atsushi AshidaOsaka Prefecture University, *Osaka Municipal Tech. Res. Inst. CuInSe2 has attracted keen attention to apply to advanced high efficiency polycrystalline thin film solar cells. It is most desirable that CuInSe2 thin film as an optical absorption layer in a solar cell has (112) preferred orientation. Because, it is very remunerative terms for fabricating heterojunction with wide gap semiconductor thin film as window layer. On the other hand, CdS is employed as a material for high resistivity window layer in cells, because of ease of preparation, and ITO or ZnO is applied to transparent conductive layer. Though, existence of CdS / ITO or ZnO interface is disadvantageous in a solar cell. Furthermore, using Cd is undesirable. So, it is expected to unify those two layers with ZnO that may be n-type semiconductor and transparent conductive material. To realize such demands, we tried to prepare CuInSe2 and ZnO thin films with processes introducing a new concept of functionally graded material (FGM). English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 177-180 熱電複合傾斜機能構造材料の熱電特性制御メカニズム Thermoelectric Properties Control Mechanism for MultiFunctionalIy Graded Thermoelectric Material 梶川武信湘南工科大学　251　神奈川県藤沢市辻堂西海岸1-1-25 T. KajikawaShonan Institute of Technology , Tsujido-nishikaigan 1-1-25 Fujisawa, Kanagawa 251, Japan Thermoelectric performance is determined with the three factors, namely, Seebeck coefficient alpha(V/K), electrical conductivity sigma(S/m), thermal conductivity kappa(W/mK). The figure of merit of thermoelectric material is represented as alpha 2 sigma/kappa. For metal and single crystalline semiconductor, those factors have close relationship each other. However, as the sintered, impurity doped polycrystalline thermoelectric material has various levels of superstructures from macro scale to micro one as for the carrier transport mechanism, the relationship among them is more complex, and it can be said that it shows the possibility of enhancement of the performance. For our research, the thermoelectric properties control mechanism is clarified by the investigation of the characteristics of the thermoelectric material of various doping levels and hot-press conditions to make the thermoelectric elements for which the temperature dependence of the performance is controlled due to FGM approach. Antimony doped, hot-pressed magnesium silicide made by spark plasma sintering has been studied in this research. In the experiment the temperature dependence of Seebeck coefficient alpha , electrical conductivity sigma and Hall mobility could be obtained for the sintered elements of the different sintering temperatures and the different dopant concentrations. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 181-184 光学的傾斜機能ポリマーの分子設計と特性評価 Design and Characterization of Functionally Graded Photonics Polymer Materials 小池康博・二瓶栄輔・石榑崇明慶応義塾大学　理工学部　223-8522 神奈川県横浜市港北区日吉3-14-1 /神奈川科学技術アカデミー　236 横浜市金沢区福浦 1-1-1 Yasuhiro Koike, Eisuke Nihei, and Takaaki IshigureFaculty of Science and Technology, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama 223 Japan / Kanagawa Academy of Science and Technology, 1-1-1, Fukuura, Kanazawa-ku, Yokohama 236 Japan Considerable research activity lately has been focused on the development of the optical component and devices that have the capability to support the high-speed multimedia network. Silica base single mode optical fiber is widely utilized in the long distance trunk area for the order of giga bit per second transmission because of its high bandwidth and transparency. On the other hand, the conventional metallic cables in the access area network significantly limit the transmission rate to the order of kilo bit per second. However, introduction of the single mode fiber in such short-range network requires many breakthroughs in the total system cost, because of the small core size. We have proposed a large-core, high-bandwidth, and low-loss GI POF. The development of the PF amorphous polymer base GI POF particularly opened the way for great advantage in the high-speed POF network. We have investigated the formation process of refractive index profile in POF by which low modal dispersion is achieved. In this paper, design of the optimum index profile of the GI POF and its bandwidth characteristic numerically computed are described. Thermal stability and long term reliability is also one of the important issues for the realization of POF network. We describe in this paper that the thermal and long term stability of the GI POF strongly depends on the used dopant, and that the refractive index profile of the GI POF can be maintained through high temperature aging by selecting the suitable dopant. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 185-188 高分子安定化液晶による屈折率傾斜特性とその応用 Graded-Refractive-Index Properties in Polymer Stabilized Liquid-Crystals and their Applications 佐藤進秋田大学　電気電子工学科 Susumu SatoDepartment of Electrical and Electronic Engineering, Akita University Since the molecular orientations in the LC cells can easily be controlled by applying a relatively low voltage, recently many investigations into their practical application as flat-panel-type display devices have been carried out. The focal length of the lens-shaped cells and the deflection angle of the prism-shaped cell can be varied from the value for an extraordinary ray to that for an ordinary ray by applying an electric field across the cells. We also proposed and demonstrated a LC optical element such as a LC microlens, based on a reorientation of LC molecules in an inhomogeneous electric field produced by a hole-patterned electrode structure, where a graded-refractive-index profile was induced by an axially symmetric nonuniform electric field. The optical properties of the LC microlens have been investigated and reported. An anamorphic LC microlens is prepared using elliptically-patterned electrode structures, where the focal length and astigmatism can easily be controlled by an ellipticity of a patterned electrode and an applying voltage. In addition, a novel beam-steering device that makes use of a nematic LC with a divided hole-patterned electrode structure is proposed and demonstrated. However, they have a disadvantage such that the graded-refractive-index profile is disappeared when the applied voltage is removed. Recently, UV curable LC materials which have a nematic phase at room temperature have been synthesized and are receiving great attention as novel LC materials. However, the graded-refractive-index properties have been frozen and they can hardly be varied by an electric field unlike the case using the usual nematic LCs. In this research project, polymer stabilized LC cells with the graded-refractive-index profile are prepared using a mixture of nematic LC and a small amount of UV curable LC materials. They are expected to have the variable graded-refractive-index properties but their lens properties will be held without voltage application and the response properties can be improved. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 189-192 バンド・ポテンシャルの設計による3-1 a-Si1-xGex(x=0-0.5)組成傾斜合金の光注入キャリア輸送特性制御 Control of Carrier Transport Properties of A-Si1-xGex:H(F) Alloy by Designing Band Potential 白井肇埼玉大学　工学部　338　埼玉県浦和市下大久保255 Hajime ShiraiFaculty of Engineering, Saitama University, 255, Shimo-Okubo, Urawa, Saitama 338, Japan For further improvement of the performance of optoelectrical devices such as solar cell and sensors, it is required to design the highly photoconductive Si related films with low defect density as well as the precise control of the internal band potential. Our motivation is based on the formation of the band potential during the film fabrication processes. To this aim, the plasma-enhanced CVD (PE-CVD) is applicable among various film fabrication techniques. We have designed highly photoconductive Si based thin films by PECVD with the internal potential gradient to improve the performance of the solar cell and studied the carrier transport properties. To introduce the material designs such as a compositional gradient or multilayered structures, several conditions are needed as follows. First is highly photoconductive a-Si:H, (mu)c-Si:H and thier based materials (a-SiGe). Second is the no interuption of RF plasma by supplying the guest molecules gradually. And the third is no additional defects in the tail states by changing the flow of guest molecules such as GeF4 or SiH4 in this study. Thus, the development of a novel fabrication technique using plasma technologies is required to overcome these difficulties. The present reports describes (a) the design and fabrication of compositional gradients using a-Si1-xGex:H(F)(0-0.5) alloys and (b) of the Si films with the phase gradients from a-Si:H to (mu)c-Si:H toward the depth to enhance the optical absorption efficiencies of infrared region above 800nm. The carrier transport properties were systematically studied in a-Si1-xGex:H(F)(0-0.5) gradient structures with different potential slope (dV/dX). In addition, highly photoconductive a-Si:H(Cl) and (mu)c-Si:H(Cl) films have been designed at high deposition rate from SiH2Cl2/SiH4/H2 for application to solar cell. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 193-196 選択的還元によって傾斜機能を持たせた高光歪セラミックスの開発 Functionally Graded High Photoristrictive Ceramics by Preferential Reduction 野間竜男、和田智志東京農工大学　工学部　応用分子化学科　184-8588 東京都小金井市中町2-24-16 Tatsuo Noma and Satoshi WadaDepartment of Applied Chemistry, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan One of the unique property seen in ferroelectric ceramics is photoristrictive effect. This is a combination of photovoltaic effect and piezoelectric effect. For practical application, there are three important obstructions to be overcome. 1) UV light irradiation, 2) small strain (1x10**(-4)) and 3) slow response (1sec~). The authors have successfully shifted the driving wave length up to 380nm by substituting the rare earth trivalent ions in PLZT which results in the broadening of band gap. The response can be improved by reducing the resistivity. However, the small strain problem has not been well solved yet. A piezoelectric material called RAINBOW (Reduced And INternally Biased Oxide Wafer) ceramics have been paid a lot of attention. A RAINBOW ceramic is fabricated through a preferential reduction by heat treating a ferroelectric ceramic (wafer) with contacting a graphite plate on the either surface. The un-reduced region shows the piezoelectricity and the coupling factor of the whole material is improved by the high conductivity caused by the reduction. Also a thermal strain mismatch between the reduced/un-reduced phases results in the increase of piezoelectric strain. In the present work, to solve the problems 2) and 3), a preferential reduction of PLZT photoristrictive ceramics was conducted. A) Improve the ratio of electric to mechanical energy transformation by increasing the coupling factor and thermal strain. B) Improve the ratio of light to electric energy transformation and also response by adding a graded conductivity. The aim of the present work is to develop an improved photoristrictive actuator which shows a high strain and a quick response. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 197-200 分子性傾斜配向を有する光伝導性液晶材料の光電特性 Photo-electric Properties of Photoconductive Liquid Crystals with Graded Molecular Alignment 半那純一 舟橋正治東京工業大学　工学部　像情報工学研究施設　226-8503　横浜市緑区長津田町 4259 Jun-ichi Hanna and Masahiro FunahashiImaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan Liquid crystals exhibiting self-organizing behavior based on weak intermolecular interactions are utilized for display devices owing to the optical anisotropy induced by the molecular alignment sensitive to the surface properties of the substrate and to applied electric field. This indicates that the liquid crystals are an attractive materials system in which we can expect new phenomenon and properties induced by a molecularly graded alignment. We paid attention to the functionalized liquid crystal which enjoys a bulk fluidity and self-organizing molecular alignment in order to create new sophisticated functionality materials and have firstly synthesized a photoconductive smectic liquid crystal, 2-(4'-Heptyloxyphenyl)-6-dodecylthiobenzothiazole (7O-PBT-S12), firstly. It was demonstrated that 7O-PBT-S12 exhibits a fast hole mobility of 6x10-3 cm2/Vs which is 10**3 times faster than that of conventional polymer based photoconductors. More recently, we have succeeded in the synthesis of a new photononductive smectic liquid crystal, 2-(4'-octylphenyl)-6-dodecyloxynaphthalene (8-PNP-O12) which exhibits ambipolar and fast electronic mobilities of 6x10**-3 cm2/Vs for electrons and holes. The aim of the present study is to investigate effects of molecularly graded alignment in photoconductive liquid crystal cells on photo-electric properties and new properties. In the first phase, the major effort will be made in establishment of the graded molecular alignment with the photoconductive liquid crystal. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 201-204 光学的線形・非線形傾斜機能型ガラスセラミックスの製造と評価 Fabrication and Characterization of Optically Linear/Nonlinear Functional Graded Glass-Ceramics 小松高行、紅野安彦、坂井亮介長岡技術科学大学　化学系　940-21長岡市上富岡町1603-1 T. Komatsu, Y Benino and R. SakaiDepartment of Chemistry, Nagaoka University of Technology; 1603-1 Kamitomioka-cho, Nagaoka 940-21, Japan Recently, we succeeded in fabricating transparent TeO2-based glass-ceramics such as K2O-Nb2O5-TeO2 and discovered that the glass-ceramics show a second harmonic generation (SHG). Further, we proposed optically linear/nonlinear functional graded glass-ceramics in which alkali metal ions are graded. Our idea was based on the fact that SHG depends on alkali metal species. For example, transparent Na2O-Nb2O5-TeO2 glass-ceramics do not show SHG. In materials with a gradient in optical nonlinearity, it is possible to convert light energy (SHG) and confine light, and it is considered that a graded structure itself is just like a device. In this study, we tried to fabricate new materials in which a crystallized fraction or glassy fraction is graded. Such new transparent graded glass-ceramics will lead to the fabrication of optical functional graded glass-ceramic fibers with a crystallized core showing SHG and with a glassy clad. At the interface between the core and the clad, a crystallized fraction would be graded. We also try to prepare Er3+doped transparent glass-ceramics, leading to the fabrication of functional graded materials with optical amplification. In glass and glass-ceramic processing, there are many advantages for the preparation of materials such as long fibers and optical waveguides. TeO2-based glasses with low phonon energies show various unique properties, and recently their optical nonlinearities have been extensively studied. To our best knowledge, the research on transparent optical functional graded TeO2-based glass-ceramics, however, has not been carried out so far. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 205-208 非晶質傾斜超格子を用いた極低雑音アバランシェ増幅型光導電膜の研究 AvaIanche MuItipIication Photodiode FiIms using FunctionaIIy Graded Super lattice Struoture. 安藤隆男　澤田和明　中西洋一郎静岡大学　電子工学研究所　432-8011静岡県浜松市城北3-5-1 Takao Ando, Kazuaki Sawada and Youichirou NakanishiResearch Institute of Electronics, Shizuoka University, Johoku3-5-1, Hamamatsu, Shizuoka, 432-8011, Japan High resolution and high sensitive image sensors have been desirable. However, as the resolution is increased, the size of the pixels will be reduced. Then, photons introduced in the photodiode area decrease. This leads a degradation of a signal to noise ratio of the image sensor. So it is necessary to realize a photo-conversion device for a next generation imaging sensor that amplify photo-signals larger than 100% quantum efficiency with noise free. The a-Si:H film can be absorbed the visible light efficiently, and it is compatible with the conventional CCD (Charge Coupled Device) process. It seems that a a-Si:H photodiode film is suitable for a photo-conversion film of the stacked type image sensor. The avalanche process is intrinsically statistical in nature so that individual carriers have different avalanche gains characterized by a distribution with an average. This causes the excess noise. On the conventional avalanche photodiodes, the increment of the noise is exceeded the increment of the photo-signal. To realize an avalanche photodiode with excess noise free, the concept of the staircase avalanche photodiode with linearly graded multilayer structure is accepted. On the staircase APD, the avalanche process is much less random than in a conventional APD, because each electrons are impact-ionized once at after each conduction band step and then the multiplication occurs only at a well-defined position in space. In this report, we report the characteristics of an a-Si:H/a-SiC:H staircase photodiode with linearly graded-gap multiplication regions. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 209-212 多孔質傾斜機能熱電材料の製作と最適化 Synthesis and optimization of functionally graded porous thermoelectric materials 大中逸雄、安田秀幸、梶浦英亮、矢野哲也大阪大学　知能・機能創成工学 Itsuo OHNAKA, Hideyuki YASUDA, Hideaki KAZIURA, Tetsuya YANODepartment of Adaptive Machine Systems Osaka University Thermoelectric materials have been extensively studied in the application to power generation systems. Recently, Echigo et. al have proposed a new thermoelectric power generation systems using porous thermoelectric device. In this system, a flammable gas flows through the porous device, cooling the device, and burns at the end of device. Gas can drive heat energy from the cold side to the hot side, like heat pump. Consequently large temperature difference between inlet and outlet of porous device is caused without any additional cooling system. There are some features of the porous thermoelectric devices. One is the large temperature gradient in the porous media and the other is that the hot side of the device contacts with flames. Therefore the thermoelectric device is required to exhibit high thermoelectric power in a wide temperature range and to have resistance to oxidation at high temperatures. It is, however, difficult to achieve these requirement by a single phase materials. Functionally graded materials which satisfy the following requirement can achieve good thermoelectric performance. (a) Oxidation resistance at high temperatures (b) High performance in wide temperature range (c) Porous structure which causes optimum temperature profile In this study, our target is synthesis and development of porous thermoelectric devices by functional graded materials of oxidation resistance (chemical properties), thermoelectric properties and porous structure (physical properties). First of all, processing of porous media formation has been investigated, since few studies has been done for porous thermoelectric materials. 1. Production of porous materials (especially brittle materials like FeSi2, PbTe) 2. Synthesis of porous thermoelectric device for functionally graded materials 3. Evaluation of the porous thermoelectric devices For the first aim, the porous devices were produced by laser irradiation and hot press method including SPS method. Prototypes of functionally graded FeSi2(Bi,Sb)2Te3 and FeSi2/PbTe porous thermoelectric devices were also produced. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 213-216 ポテンシャルの傾斜した導電性高分子の光増感反応を用いた製造 Fabrication of a Potential-Graded Phase in a Conductive Polymer Film Using Photosensitized Reactions 山下和男　播磨裕広島大学　総合科学部　生物圏科学研究科〒739-8521東広島市鏡山1-7-1 Kazuo Yamashita and Yutaka HarimaDivision of Material and Life Sciences, Faculty of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 7398521, Japan In the last two decades polymeric semiconductors have received significant attention as new functionality organic materials applicable to solar cells, light emitting diodes, batteries and electrochromic devices. A valence control or an impurity doping technique is widely used for fabricating a potential-graded phase in an inorganic semiconductor. However, it is not a method generally applicable to organic semiconductors. Establishment of a technology for fabricating a potential-graded phase in an organic semiconductor would be a new approach to the construction of new organic devices or more efficient ones. Recently, we have reported a photosensitized doping (PSD) and dedoping method using tris(2,2'-bipyridine)ruthenium(II) ([Ru(bpy)3]2+) and peroxydisulfate (S2O82-) or triethanolamine as a sensitizer and an oxidative or a reductive quencher, respectively. In this report we describe the modified PSD technique. The electrochemical version of the PSD method is based on the combination of the controlled-potential electrochemical doping and the PSD. Using the potentiostatic PSD (PPSD) method a potential-graded phase in the direction of the thickness in a polymer film can be readily fabricated. In addition, we show electrochemical and spectroelectrochemical properties of poly[sylanylene(oligothienylene)]s such as poly[(diethylmonosilanylene)penta(2,5-thienylene)] (MS5T) and poly[(tetraethyldisilanylene)penta(2,5-thienylene)] (DS5T), which are promising materials applicable to conductors and photoresists, etc., and the application of the PSD method to preparation of images on a thin film of MS5T. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 217-220 プラズマ粉体処理によるミクロ傾斜機能構造を有する熱電材料焼結体の開発 Development of thermoelectric sintered materials with functionally graded microstructures prepared by plasma powder treatement 小柳剛、岸本堅剛、松原覚衛＊山口大学　工学部　755　宇部市常盤台2557＊山口東京理科大学　756　小野田市大学通1-1-1 T. Koyanagi, K. Kishimoto and K. Matsubara*Faculty of Engineering, Yamaguchi University, 2557, Tokiwadai, Ube 755, Japan *Science University of Tokyo in Yamaguchi, 1-1-1, Daigakudori, Onoda 756, Japan There is a possibility of improvement of the thermoelectric performance in the thermoelectric sintered materials of which microstructures are controlled since not only a decrease in the electric resistivity but also a decrease in the thermal conductivity and an increase in the Seebeck coefficient can be expected. In this study, we have investigated the control of microstructures in thermoelectric sintered materials by the plasma powder treatment technique in order to improve their thermoelectric performance. Functionally graded structures can be formed at grain boundaries of sintered materials by sintering their raw powders of which surfaces are modified in reactive plasmas. These sintered materials are regarded as a kind of the functionally graded materials (micro-FGM). In this year, we have studied the Si-Ge and Bi-Sb thermoelectric sintered materials. For the Si-Ge materials, the improvement of thermoelectric performance by the energy filtering effect has been investigated. This effect is expected to be realized on the SiGe/Si composite, in which SiGe grains are surrounded with Si layers, sintered using the SiH4-plasma treated SiGe powder. For the Bi-Sb materials, the thermoelectric properties of Bi sintered using its raw powder treated in Ar, H2, O2 and SbCl3+H2 plasmas have been investigated as a preliminary experiment in order to improve the thermoelectric performance of Bi-Sb alloys. We aimed at various kinds of surface modification of Bi powder, that is, etching and/or disordering of surface atoms by bombardment of Ar+ ions for the Ar plasma treatment, reduction of O for the H2 plasma treatment, oxidation for the O2 plasma treatment, and coating of Sb for the SbCl3+H2 plasma treatment. Further, we also investigated the thermoelectric properties of Bi-Sb alloys sintered using their O2-plasma treated powder. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 221-224 生物を模倣した高分子傾斜材料の設計 Biomimetic Design of Polymeric FGM 小野勝道茨城大学　物質工学 Katsumichi OnoDepartment of Materials Science, Ibaraki University The main object of A04 research group is to prepare FGM ranging nm to cm sizes by chemical and biochemical reaction as well as to clarify the graded structure of various biological tissues. In order to control the size of the FGM structure, it is necessary that the reactant has an appropriate rate of mass transfer and that the reaction product is practically immobilized. Generally, we reduce the rate of mass transfer of the reaction product by quenching the reaction. In the case of biological tissue, the rate of mass transfer is reduced by the formation of immobilized products without quenching the reaction. In this study we analyzed a simple model system where the reactant having the diffusion coefficient D forms immobilized product by n- th order reaction. The condition for the formation of FGM is derived by analyzing the model system using theoretical and/or numerical calculations. The results were compared with experimental profile of graded structure. Finally we also discussed the control of the size of FGM and that of the distribution function of FGM. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 225-228 人工生体構成材料の作製と応用一チタン／アパタイト、チタン／コバルト系傾斜機能型インプラントの生体親和性一 The Chemical and Biochemical Functionally Graded Materials Synthesis of Biomaterials and their Application - Biocompatibility of Titanium/Hydroxyapatite and Titanium/Cobalt Functionally Graded Dental Implants- 亘理文夫、横山敦郎、佐相史徳、宇尾基弘、松野浩宣、川崎貴生北海道大学　歯学部　060-8586　札幌市北海道大学内 F. WATARI, A. YOKOYAMA, F. SASO, M. UO, H. MATSUNO and T. KAWASAKISchool of Dentistry, Hokkaido University, Sapporo 060 -8586, JAPAN Dental implant is set in the jawbone with the form penetrating from the inside to the outside of the bone to reconstruct the masticatory function. The present structure, however, is not necessarily the best form, where the whole part is composed of the single composition and uniform structure. The dental implant with the structure of functionally graded materials(FGM), for example, with the composition from the biocompatible metal , Ti, at one end , increasing the concentration of ceramics, hydroxyapatite(HAP) toward 100% HAP at the other end, could control the functions of mechanical properties and biocompatibility, depending on the necessity of each part of implant, without the abrupt change by the formation of discrete boundary. FGM of this type is expressed as Ti/100 English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 229-232 植物の階層的傾斜構造 Functionally Graded and Hierarchical Structure of Plants 天田重庚、深尾守昭、孫運涛群馬大学　376-8515　群馬県桐生市天神1-5-1 S. Amada, M. Fukao and Yuntao SunGunma University, 1-5-1 Tenjin, Kiryu, Gunma 376-8515, Japan Plants have acquired various intelligent properties for a long time to adapt to our natural environments. One of those properties is hierarchical structure, or functionally graded structure. These lead to a generation of far superior function. Of all those plants bamboo must be a typical one, which has a fiber reinforced composite. In the mechanical view point, it is anticipated that functionally graded structure has been established at each scale level. So far, the macroscopic functionally graded structure(the 1st functionally graded structure) on the bamboo shape and the microscopic one(2nd functionally graded structure) on the fiber distribution in the bamboo culm have been uncovered. The 3rd FGM structure is expected to exist in the wall structure of the vascular bundle sheath(simply called fiber) surrounding the vessels and sieve tubes. This report presents the measurements of the elastic property on fibers based on the non-destructive approach using a scanning acoustic microscope(SAM), which is concerned with the 3rd FGM level. Also the fracture toughness of the bamboo culm is discussed, which is in the 2nd FGM level. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 233-236 生体活性傾斜機能材料の設計 Design of Bioactive Functionally Graded Materials 小久保正京都大学　工学部　606-01　京都市左京区吉田 T. KokuboFaculty of Engineering, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-01 , Japan Generally, artificial materials implanted into a bone defect are encapsulated by fibrous tissue to be isolated from the surrounding bone. Some ceramics, however, come into direct contact with living bone without forming the fibrous tissue around them and bond to it. Bioglass, sintered hydroxyapatite and glass-ceramic A-W are its examples. They are now called bioactive ceramics, and used as valuable bone-repairing materials. None of the bioactive ceramics, however, can not be used as implants to replace highly load-bearing bones, since their fracture toughnesses are lower than that of human cortical bone. Some metallic materials such as Ti metal coated with hydroxyapatite by plasma spraying method are currently used as load-bearing implants. Such plasma spraying method is, however, performed at a temperature over 10,000deg.C. Control of crystallity and composition of the coated hydroxyapatite and its strong adhesion to the metal substrates are therefore very difficult. Recently, the present author showed that a simple NaOH and a subsequent heat treatments give a bioactive titanium (Ti) metal, where a sodium titanate graded structure is formed on its surface. Thus-treated Ti metal spontaneously bonds to bone via the formation of bonelike apatite layer on its surface in the body. In the process of apatite formation, a graded structure is established at the apatite-metal interface to provide tight integration of the metal with the bone. In the present study, Ti-6Al-4V alloy metal, which is more often used as load-bearing orthopedic and dental implants, was subjected to the NaOH and heat treatments to investigate whether the above kind of graded structure can be formed on its surface and how the graded structure changes in body environment. Aluminum (Al) is reported to suppress the apatite formation, and vanadium (V) is toxic in body environment. It is therefore very important in clinical application of this kind of bioactive alloy metals to clarify how the Al and V constituting the alloy affect on the formation of the sodium titanate and apatite with graded structures. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 237-240 植物体内に構築されたFGM構造による適応発現機構 Adaptive Growth Mechanisms of Design Architecture of FGMS in Plants 野方文雄姫路工業大学　機械工学科 F. NogataDepartment of Mechanical Engineering, Himeji Institute of Technology It was found that the biological electric signal from the cells of plant controls the growth activity of load carriers. Thus it was demonstrated that we can control the structures of biomaterials using specific electric signals. It is also considered that this process is the best choice to survive the hard competition for energy and external mechanical condition with minimum materials and limited living space. These findings shows that rather than developing new materials with high stiffness it might more advantageous to create structures using the optimal placement of fibers as per bamboo, mollusc shell, or porous or cellular structures of bone and plant. In addition, the self-optimizing, cell-based sensing system for analyzing external physical stimuli adapted by plants, could serve as a useful model for constructing new, intelligent, multiphase/graded materials as per systems. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 241-244 耐候性鋼安定さび層を担うクロム置換ゲーサイトの傾斜組成と大気腐食抑制機構 Graded Composition of Stable Rust Layer of Cr substituted Goethite Formed on Weathering Steel and Suppression Mechanism on Atmospheric Corrosion 三澤俊平室蘭工業大学　材料物性工学科〒050　北海道室蘭市水元町２７－１ Toshihei MisawaInstitute for Materials Science and Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido, 050, Japan Weathering steels have high atmospheric corrosion resistance by the presence of stable rust layer. On the basis of analytical results of rust layer of a weathering steel which exposed to atmosphere in an industrial area for a quarter of century, it was found that final stable rust layer of the weathering steel had a Goethite structure of (alpha)-FeOOH type and Cr containing condensely packed (alpha)-(Cr1-x,Fex)OOH(Cr substituted Goethite) grains are gradedly distributed in the rust layer. In seashore region, permeation behavior of chloride ions through rust layer influence greatly corrosion of weathering steels. Since current flow from anode to cathode are carried by the transport of ions which pass through the rust layer and electrochemical corrosion is controlled by the ion selectivity. Although main component substances in the rust layer on weathering steels are composed of various iron oxyhydroxides and iron oxides, their ion selective properties are not fully understood. In this paper, ion selectivity of iron oxyhydroxides and iron oxides were investigated by the measurement of membrane potentials from the standpoint of electrochemical ion selectivity of rust layer which is important function. Furthermore, effect of Cr content and adsorbed oxyanions on the ion selective properties of (alpha)-(Cr1-x,Fex)OOH were examined. On the basis of the results, the protection mechanism for the stable rust layer formed on weathering steels was discussed. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 245-248 イネ科植物の茎の構造と組織形成における傾斜構造の解析 Analysis of graded structure of stem in Graminaceous plants 高橋清、後藤雄佐、中村貞二東北大学　大学院農学研究科 K. Takahashi, Y. Goto and T. NakamuraGraduate School of Agriculture, Tohoku University Amada et al (1996) reported that two kinds of graded functions were found in the Graminaceous plants such as bamboo tree. One of them is the micro structure in the transverse section of the stem which may have the protective function from the outer stress. The other is the macro structure which is shown in the interval of the nodes, namely the length of the internodes. The latter may have the function of maintenance of the very high stem. As a result, the stem of Graminaceous plants is not so heavy although the stem length is very long. We have clarified that the process of the formation of graded structure in the internode lengths of the sweet sorghum and also in the transverse section of the stem. Especially the density of the vascular bundles was the highest in the surface area (periferal zone) and was the lowest in the central area (pith). On the other hand, the size of single vascular bundle was the smallest in the periferal zone and the largest in the pith. It was already reported that auxin, one of the plant hormone, has an important role in the formation of vascular bundles. It is also known that auxin is produced in the shoot apex and it moves downward as described as polar transport and that high concentration of auxin stimulated differentiation of vascular bundle whereas the size of a vascular bundle became smaller. Therefore we suggested that auxin may have a role in formation of the graded structure in the vascular bundle of the sweet sorghum. In the present report, we investigated the distribution of silica(SiO2) in the rice plant because a graded distribution pattern of silica was found in the preliminal experiments. It was also reported that large amount of silica exists in rice plant and the silica played a role as a physical support and protect from the attack of fungi such as rice blust. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 249-252 電気化学的ポテンシャル勾配を持つルテニウム三核錯体のピラゾン架橋オリゴマー Pyrazine-Bridged Oligomers of Triruthenium Cluster Complex with Electrochemical Potential Slope. 伊藤翼東北大学 大学院理学研究科　化学科〒980-77　仙台市 Tasuku ItoDepartment of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-77, Japan A triruthenium cluster complex of the type [Ru3((mu)3-O)((mu)-CH3CO2)6(L)3]+ shows reversible 4 step 1 electron redox waves in electrochemistry. It is possible to make oligomers by linking the trinuclear complex with bridging ligand such as pyrazine or 4,4'-bipyridine. Since each Ru3 unit in oligomer shows respective redox waves, it is expected to make electrochemical potential slope along the oligomer chain by arranging appropriate terminal ligands in the oligomer. Objectives of the present study are : (1) to make such Ru3 oligomers with electrochemical potential slope; (2) to investigate the relation between the electrochemical potential slope and the rate of electron transfer along the chain. The results thus far obtained show that faily strong inter-Ru3 unit interaction has to operate to show detectable effect of electrochemical potential slope on the electron transfer rate, that interunit electronic interaction takes place via pyrazine bridge (pi)*orbital, and that only the reduced species of oligomer can show detectable correlation between the slope and the electron transfer rate. In this fiscal year, we started the research aiming at the objective (2). The present study is headed for the elucidation of behavior of the long distance electron transfer along the oligomer chain. It is necessary to understand first of all the electron transfer behavior between Ru3 units deeply. Therefore, we decided to begin with investigation of electron transfer in one electron reduced species of Ru3 dimer, which is in the mixed valence state on the Ru3 unit. For this purpose, we selected a series of Ru3 dimer, in which each unit has carbonyl ligand. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 253-256 濃度傾斜表面の作成と表面反応性制御およびXPEEMシステムの開発 Preparation of the concentration graded surface and development of XPEEM imaging system for surface reaction control 朝倉清高東京大学　理学部　スペクトル化学研究センター　113-0033　東京都文京区本郷 K. AsakuraResearch Center for Spectrochemistry, Faculty of Science, The University of Tokyo, Hongo, Tokyo 113-0033, Japan Regulation of surface chemical reactions is possible by controlling the self-organized chemical waves created on the surface. In this study, we tried to regulate the propagation direction of the chemical waves by using the concentration or temperature graded surface. For this purpose, we developed a new characterization tool for the graded surface called as XPEEM(X-ray photoemission electron microscopy). XPEEM is a technique combining PEEM(Photoemission electron microscopy) and XPS(X-ray photoelectron spectroscopy). PEEM gives the real time imaging of the surface using difference in the work function of surface. Advantage of the PEEM is the possibility of in-situ measurement of the surface dynamics in the presence of gas phase components. In addition to this the XPEEM can select the electron with its kinetic energy like XPS. Thus it may be possible to map the element distribution of the surface under reaction conditions. We have developed XPEEM system to clarify the structure of concentration-graded surface and its effect on reaction waves. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 257-260 生体組織傾斜構造に類似のコラーゲン会合体を含んだ細胞培養床の作成 Cell Culture Substrates consisting of Collagen Supramolecular Aggregates in a Graded Structure 林利彦　水野一乗　広瀬志弘　中里浩一　吉川究　小杉浩章東京大学　大学院総合文化研究科　生命環境科学　153-0023　東京都目黒区駒場3-8-1 T. Hayashi, K. Mizuno, M. Hirose, K. Nakazato, H. Kosugi, K. YoshikawaDepartment of Life Sciences, Graduate School of Arts & Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-0023, Japan The infrastructure of living organ and tissue consists of a graded structure of various collagenous supramolecular structures. We hypothesize that the collagen aggregates may affect the functions of cells in contact including cell morphology, proliferation, gene expression, and differentiation through specific adhesion signals consolidated. The immunohistochemical analyses with specific antibodies suggested the graded distribution of type IV collagen, type V collagen and type I collagen. The three collagen types form the fine filaments with dimaters increasing in this order. Our results are summarized in Fig. 1a(Adachi et al, 1997) as a hypothetical general skeletal structure of tissue. The model can be combined to form further complex structures in Fig. 1b(Adachi et al, 1997). In blood vessel wall, type IV collagen, type V collagen, type III collagen and type I collagen are found in accord with the graded distribution of vascular endothelial cells, vascular smooth muscle cells and fibroblasts. Apparent correlation of the graded distributions of cell types and collagen types may be involved in maintaining the tissue homeostasis. The cellular behavior and responses may be affected by the substrates composed of collagen supramolecular structures. We here report that the type IV collagen gel showed unexpected influences on cells. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 261-264 歯質とポリマーとの傾斜機能型分子複合体の合成と接着機構の解明 Preparation of a Molecular Level Composite Having Concentration Gradient in Dentin Side with Copolymers and Analysis of the Bonding Mechanism of Copolymers to Dentin 中林宣男　石原一彦　渡辺昭彦東京医科歯科大学　医用器材研究所101-0062　東京都神田 N. NAKABAYASHI, K. Ishihara and A. WatanabeInstitute for Medical and Dental Engineering, Tokyo Medical and Dental University, Kanda, Tokyo 101-0062, Japan The bonding is very important to prevent infection at the interface when artificial materials have been implanted for medical and dental treatments. As results of the studies, it turned out that diffusion of monomers into the substrate and their polymerization in situ are essential for the adhesion and the chemical reaction between them might not be necessary. 4-methacryloyloxyethyl trimellitate anhydride (4-META, Figure 1) dissolved in methyl methacrylate (MMA) initiated by tri-n-butyl borane (TBB), was abbreviated as 4-META/MMA-TBB resin. The adhesive worked well in the bonding to dentin demineralized by an aqueous mixture of 10% citric acid and 3% ferric chloride (10-3). 4-META/MMA-TBB resin could provide new dental materials in subsurface of dentin which is called hybridized dentin. The hybridized dentin is prepared by diffusion of monomers into conditioned dentinal substrate which has high monomer permeability and the polymerization of impregnated monomers in situ. Monomers must have high potential to promote diffusion of monomers into tooth substrates to create the hybrid layer. Methacrylate with both hydrophobic and hydrophilic group is essential to provide such biocompatible monomers. Reliable bonding of polymers to dentin became possible as it can unite the natural tissues with polymers. It is neither tooth elements nor polymers, but a molecular level mixture of the two. It is a acid resistance impermeable membrane created in the subsurface of dentin and can prevent recurrent caries and invasion of stimuli coming to the pulp which induces irritation of pulp. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 265-268 DNA二重らせん鎖の配向固定化傾斜機能フィルム Functionally Graded Films in which DNA Double Strands are aligned 岡畑恵雄東京工業大学　生命理工学部　226　横浜市緑区長津田 Yoshio OkahataDepartment of Biomolecular Engineering,Tokyo Institute of TechnologyNagatsuda, Midori-ku, Yokohama, 226 Japan DNA is important as a source of biological information depending on base sequences. DNA is also interesting as a molecular material that shows a long double helical structure with base-pair stacking: the base separation is 3.4 angstrom while the diameter of the helix is about 20 angstrom. It therefore is a good candidate for gradually graded electron conduction materials. In this report, we describe two methods to prepare organic thin films in which DNA strands aligned in one direction by i) uniaxial stretching of a cast film of DNA-lipid complex and ii) vertical dipping LB method of anionic DNA strands with cationic lipid monolayers. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 269-272 粘土層間のスピロピランイオンのインターカレーションの増進 An Enhanced Intercalation of Ionic Spiropyrans in Clay 高木克彦　志知哲也　小木曽博貴名古屋大学　大学院工学研究科　結晶材料工学科〒464-01名古屋市千種区不老町 Katsuhiko Takagi, Tetsuya Shichi, and Hiroki OgisoDepartment of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-01 Clay minerals exhibit an intercalation capability to adsorb various organic guest molecules on their layer surfaces by ionic exchange with such counterions as sodium, lithium, and so on. The amount of adsorption is defined as the cation-exchange-capacity (CEC) which designates the milliequivalent of counterions per 100 grams of clay. Thus, in the case of intercalation by ionic exchange with the counterion, the amount of guest molecules can be controlled by the CEC of the clay. For instance, montmorillonite clay can accommodate stilbazolium cations quantitatively up to the CEC of the clay, but over the CEC, the adsorption sites are saturated and the amount of guest cations levels off, as shown in Figure 1. A typical montmorillonite clay, Kunipia F, is known to possess, on average, approximately one exchangeable sodium cation molecule per 100 square angstrom. Therefore, judging from the fact that the cross-section area of the molecule is estimated to be around 30 square angstrom, it is unlikely that a dense packing of the stilbazolium ions on the surface of the clay can be attained, which is in contrast to the molecular packing observed in typical organic crystals and LB membranes. In order to fully utilize organic-inorganic hybrid materials including functional guest molecules in clay, it is vital to construct clay interlayers which is as densely packed with the aggregates of the guest molecules as possible. In the present investigation, we have undertaken the task of realizing a method of obtaining the most densely packed molecular aggregates as possible in the clay by the intercalation of guests molecules far exceeding the CEC. By employing such procedures, we have presented a new methodology for the enhanced intercalation of zwitterionic guest molecules. These adsorption characteristics explicitly reflect the grated functionality between the intercalated guest molecules and the added molecules in a range of up to ca.400% based on the CEC of the clay. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 273-276 不均質系アパタイトの合成設計と生体材料への応用 Synthesis Design of Heterogeneous Apatites and Their Application to Biomaterials 岡崎正之　高橋純造　荘村泰治　寺岡文雄　平雅之　前田芳信大阪大学　歯学部　565　大阪府吹田市山田丘1-8 M. Okazaki, J. Takahashi, T. Sohmura, F. Teraoka, M. Taira and Y. MaedaOsaka University, Faculty of Dentistry1-8 Yamadaoka, Suita, Osaka 565, Japan Apatite formation occurs sometimes heterogeneously in some biological systems. To investigate such heterogeneous precipitation phenomena in biological systems, we are continuing our synthesis experiments. Fluoridated hydroxyapatites were synthesized heterogeneously using a two-step fluoride supply system. Two different types of heterogeneous fluoridated apatites were formed: hydroxyapatite covered with fluorapatite, and fluorapatite covered with hydroxyapatite. There are various fluoridated apatites with different degrees of fluoridation (the degree of fluoridation X=0: hydroxyapatite, X=1.0: fluorapatite). In this study, heterogeneous fluoridated hydroxyapatites were synthesized with various fluoride concentrations equivalent to those from hydroxyapatite to fluorapatite. In addition, a three-step fluoride supply system was also adopted for apatite synthesis. Furthermore, in human teeth the negative gradient of fluoride concentration from the surface of tooth enamel toward dentine-enamel junction can be formed. We speculate that even each crystal composing enamel layer may have a distribution. Therefore, we newly created a continuous gradient fluoride supply system by developing the previous step-like fluoride supply system in this study. English Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on PriorityArea, No. 274 The Ministry of Education, Science, Sports and Culture of Japan Physics and Chemistry of Functionally Graded Materials Research Report 1997Grant-in-Aid for Scientific Research on Priority Area, No. 274 4 1998-03-01 277-280 光反応を用いた微少領域での傾斜機能高分子表面の作成と細胞機能発現の制御 Preparation of Functionally Gradient Polymer Surfaces with Micron-Order Precision using Photochemical Reaction and Cellular Responses 中山泰秀・松田武久国立循環器病センター研究所　生体工学部565　大阪府吹田市藤白台5-7-1 Y. Nakayama and T. MatsudaDepartment of Bioengineering, National Cardiovascular Center Research Institute, Fujishiro-dai 5-7-1, Suita, Osaka 565, Japan Since the surface structure, composition and properties at the outermost layers of blood- or tissue-contacting surfaces determine the biological responses to biomedical devices, surface design in the devices is crucial with regard to whether implanted devices can be accepted or rejected by body defense mechanisms. Both nonionic hydrophilicand hydrated surfaces are generally considered to be resistant to both protein adsorption and cellular adhesion, while hydrophobic or ionic surfaces are thought to promote protein adsorption and cellular adhesion, spreading, and proliferation. Within a single device, there may be several different local microenvironments, each with its own set of requirements for efficacious cell-material interactions. Thus, there is considerable impetus to develop regionally specific, multifunctionalized surfaces for the purpose of studying these localized cellular interactions. In the last year, we have developed a surface modification technique that enables the generation of graft-polymerized surface with micronorder regional precision. The technique is based on photochemistry of benzyl dithiocarbamate 'iniferters' (Figure 1). Since the reaction proceeds only during photoirradiation and at photoirradiated regions, the reactive zone can be easily controlled using a photomask. Using surface photo-graft copolymerization via benzyl N,N-diethyldithiocarbamate free radical chemistry, we have deposited hydrophilic nonionic regions on hydrophobic biomedical polymers. In this year, we prepared three different three dimensional photo-grafted gradient surfaces, and then exampled the endothelial cell adhesion and proliferation on these surfaces. The gradient surfaces allowed a controlled examination of the effect of polymer chain length on the cellular response within one physical sample. With these novel surfaces, the initial studies involving the simultaneous characterization of the cellular response in multiple microenvironments have been completed. English