日本金属学会誌
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
33 巻, 9 号
選択された号の論文の21件中1~21を表示しています
  • 古沢 浩一, 田中 一英
    1969 年 33 巻 9 号 p. 985-991
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The interaction of carbon and nitrogen atoms with dislocation in iron was studied by measuring the amplitude dependent internal friction. The measurements were carried out on three specimens containing 10 ppm C, 1 ppm C and 5 ppm N, respectively, by the forced transverse vibration method. The binding energies between these interstitial impurities and dislocation were obtained as a result of an analysis based on the theory proposed by Granato and Lücke. The amplitude dependent internal friction is so sensitive to the locking of dislocations by impurities that the binding energies thus determined are considered to be more reliable than those ever reported. The results are summarized in the following:
    (1) The binding energies are 0.55 eV for carbon and 0.80 eV for nitrogen, respectively.
    (2) If a calculated binding force between a carbon atom and a dislocation (0.1Gb2) is used, the mean pinning lengths obtained from the amplitude dependent internal friction are in good agreement with those estimated from a thermodynamic equation.
  • 岡田 克己
    1969 年 33 巻 9 号 p. 991-999
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    For the purpose of investigating the drawability of S.A.P., hot-rolled Al-Al2O3 alloys containing Al2O3 from 1.2 to 15.5 wt% were deep drawn at high and room temperatures. As to the maximum deep drawability, the limiting drawing ratio of 2.10 was obtained on Al-3.5%Al2O3 alloy. The cup profile obtained on Al-Al2O3 (3.5%) alloy showed 50° ears from the rolling direction. The ears disappeared at over 9.8 wt%Al2O3, and the new ears pararell to the rolling direction were formed. The pole figures of Al-Al2O3 alloys with 3.5 wt%Al2O3 showed that the preferred orientation is (110)[\bar335], and the relation between the ears and pole figures are discussed. The mechanism of forming the (110)[\bar335] texture seemed to be due to the operation of a new slip system other than the primary and conjugate slip systems. It appears that the new slip system has the same slip plane as the primary or the conjugate slip plane and its slip direction is equal to the crossing line between the primary and conjugate slip planes.
  • 増本 量, 沢谷 昭八, 菊地 紀雄
    1969 年 33 巻 9 号 p. 999-1003
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    Measurements of the thermal expansion, natural frequency of vibration and magnetization of ferromagnetic cobalt-manganese alloys were carried out at various temperatures, and a new equilibrium diagram was constructed. The equilibrium diagram shows that the ε-α transformation continues up to a composition range of 19.30%Mn and the magnetic transformation point in the α phase is 0°C at a concentration of 28.20%Mn. Further, the coefficient of thermal expansion and the temperature coefficient of Young’s modulus at room temperature were determined, from which it has been ascertained that a Co-23.85%Mn alloy in the ferromagnetic region of α phase shows a minimum value of 14.04×10−6 in thermal expansion coefficient and a maximum value of 2.52×10−5 in temperature coefficient of Young’s modulus. The cause of such abnormal properties of the alloy can be explained by Masumoto’s rule in regard to Invar.
  • 増本 量, 沢谷 昭八, 中村 直司
    1969 年 33 巻 9 号 p. 1003-1006
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    Measurements of the linear coefficient of thermal expansion, Young’s modulus and its temperature coefficient, and density were carried out so as to investigate effects of Cr, Mo or W additions on the anomaly of Young’s modulus, i.e. the Elinvar property, of nickel at high temperature. It was found that in the Ni-Cr, Ni-Mo and Ni-W binary systems the Elinvar property of nickel at high temperature falls down gradually to room temperature along the magnetic transformation point with increasing addition of each element, and also a minimum linear coefficient of thermal expansion, characteristic of the Invar property appears in a composition range where the Elinvar property is revealed.
  • 増本 量, 村上 雄悦, 比内 正勝
    1969 年 33 巻 9 号 p. 1007-1011
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    Masumoto et al. previously discovered that alloys near in composition to Ni3Mn exhibited a high magnetic permeability when these alloys had an optimum degree of order, and named them “Nimalloy”. A great deal of works have since been carried out on the effects of additions of various elements on the properties of nickel-manganese alloys, and consequently the highest initial permeability of 76000 and the highest maximum permeability of 441000 have been obtained.
    In the present study additions of germanium to nickel-manganese alloys showed that the initial and maximum permeabilities of nickel-manganese alloys increased gradually at the beginning and then rapidly attained a maxima, and afterwards decreased gradually. The highest initial permeability of 15180 was obtained on the alloy of 77.89%Ni, 17.98%Mn and 4.13%Ge when cooled at a rate of 240°C/hr from 900°C and reheated at 400°C for 10 hr, and the highest maximum permeability of 167000 on the alloy of 78.27%Ni, 17.11%Mn and 4.62%Ge when cooled at a rate of 240°C/hr from 900°C and reheating at 400°C for 8 hr. The latter alloy shows a coercive force of 0.0046 Oe and a magnetic hysteresis loss of 12.58 erg/cm3/cycle for the maximum magnetic induction of 2000 G, and its electrical resistivity being 65.4 μΩ-cm at 20°C.
  • 五弓 勇雄, 鈴木 敬治郎, 藤倉 潮三
    1969 年 33 巻 9 号 p. 1012-1017
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The dependences of stretch-formability on crystallographic orientation and work hardening exponent n for metal sheets were investigated. The results showed that in aluminium single crystal plates stretch-formed the (100) oriented single crystal sheet has the best stretch-formability. Therefore copper sheets with various amounts of the (100)[001] orientation were stretch-formed and the effect of the (100)[001] orientation on the stretch-formability was studied.
    On the other hand, brass and aluminium sheets annealed at various temperatures were stretch-formed and the contribution of work hardening exponent n to the stretch-formability was studied. The results obtained are summarized as follows:
    (1) There is little effect of the crystallographic orientation on the stretch-formability.
    (2) Stretch-formability is nearly independent of strain ratio r.
    (3) Stretch-formability has little bearing on the observed values of work hardening exponent n at 10% strain, but it is considered that work hardening exponent at fracture represents the stretch-formability.
    (4) Elongation is closely related to the stretch-formability; the more the material is elongated in tension, the more excellent is it in strech-formability.
  • 浜崎 美智子, 五弓 勇雄, 岡村 俊一
    1969 年 33 巻 9 号 p. 1017-1023
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    It is one of the disadvantages in the use of 18% chrome stainless steel that a ridging phenomenon occurs when the cold rolled and annealed sheet or strip is drawn. The principal objects of the present study was to investigate a method to eliminate the ridging phenomenon and to clarify its origin, cesing commercially produced 18% chrome stainless steel. The results obtained were as follows: (1) The optimum treatment for 18% chrome stainless steel to develop the suitable mechanical properties is to heat-treat at 1100°C for 1∼3 min. (2) The facts that any ridging phenomenon did not occur either by quenching at 1100°C or by slow cooling from 1100°C, and the ridging phenomenon appeared in the rolling direction independent of the elongated direction, prove that the ridging phenomenon is not connected directly with the martensite itself. (3) As for the stainless steel with lower C and N contents(without α-γ zone), the ridging phenomenon is always shown by any heat treatment. (4) Cr is segregated at only grain boundaries, and this segregation is considered to have no direct relation with the ridging phenomenon. Mn is almost uniformly distributed. (5) The distribution of Cr and Mn is found to be independent of the C and N contents. Therefore, there would not be direct relation between the dispersion of chromium carbide and the ridging phenomenon. (6) The ridging phenomenon is closely related to the Fe-decreased banded structure produced by cold rolling.
  • 増本 健, 武田 滋, 今井 勇之進
    1969 年 33 巻 9 号 p. 1024-1030
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    Precipitation characteristics of 12%Cr steel during isothermal tempering were studied mainly by a transmission electron microscope. As the result, the shape, nucleation site and habit plane of each carbide (Fe3C, (Cr, Fe)7C3, (Cr, Fe)23C6), and the orientation relationships between carbides and ferrite matrix were clarified. It was confirmed that the transformation from Fe3C to (Cr, Fe)7C3 occurs by both in situ and separate nucleation and the transformation from (Cr, Fe)7C3 to (Cr, Fe)23C6 by separate nucleation at grain boundaries. Furthermore, it was concluded that the secondary hardening may be induced by the distribution of fine granular particles of (Cr, Fe)7C3 nucleated separately on the dislocations in the region of high dislocation density.
  • 今井 勇之進, 行方 二郎
    1969 年 33 巻 9 号 p. 1030-1035
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The precipitation behaviour of V4C3 and the structural change in Mn-Cr-V type austenitic steel with a chemical composition of 0.44%C, 17.40%Mn, 12.15%Cr and 2.37%V have been studied by measuring the changes in dilatation and hardness and by transmission electron microscope observations. The results obtained are as follows:
    (1) The precipitated carbide which brings about a remarkable hardening and dilatation change is spherical V4C3 only.
    (2) The strain field caused by the coherency between V4C3 and the matrix is released when the particle size grows up to a diameter of 150∼160 Å, resulting in contraction and the hardness decrease of the austenic steel. This suggests that the coherency between V4C3 and the matrix plays an important role in the strengthening of austenitic steel in the Mn-Cr-V system.
  • 三浦 維四, 浜中 人士
    1969 年 33 巻 9 号 p. 1036-1041
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    In recent years increasing attension has been given to the production of eutectic fibrous composites produced by the unidirectional solidification technique. For binary alloys, many kinds of eutectic composites have been reported, but very little has been known about ternary eutectics. In this paper, the preparation of an Al-Si-Al3Ni ternary eutectic fibrous composite has been investigated by means of unidirectional solidification. And growth mechanism of the ternary eutectic composite was discussed.
    The main results are as follows: (1) In the controlled microstructure of Al-Si-Al3Ni eutectics, platelet silicon and Al3Ni rods were aligned each other in a growth direction in the aluminum matrix. (2) Increasing the rate of solidification caused the interesting change of microstructure and altered the type of growth profile of the silicon colony. (3) The growth mechanism of the silicon phase in the aluminum matrix was remarkably modified by the addition of nickel atoms, so the microstructure of Al-Si-Al3Ni eutectic alloy can more easily be controlled than that of Al-Si eutectic alloys.
    From this investigation it has been concluded that some serious shortcomings of the eutectic approach to reinforced composites may be greatly improved by the addition of third or more elements.
  • 杉本 克久, 沢田 可信, 森岡 進
    1969 年 33 巻 9 号 p. 1042-1048
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The impedance of the system aluminium-surface film-aqueous halide solution has been investigated by means of the apparatus consisting of a potentiostat and an A.C. bridge. The results obtained may be summarized as follows:
    (1) The series capacitance component of the impedance between aluminium and the solutions of pH 9.26∼11.15 has a maximum value at the potential intermediate between the corrosion potential and the pitting potential of the specimens, namely approximate −1.15 V (vs.S.C.E.). Its series resistance component also has a minimum value at the same potential. These phenomena are considered to result from the decrease in thickness of the surface films near that potential. In neutral solutions, these phenomena are not observed.
    (2) The dissipation factor (tanδ) of the surface film on aluminium formed anodically in aqueous halide solutions grows larger with increasing potential to the noble direction. It is suggested that the defect density in the surface film increases near the pitting potential of the specimen.
    (3) A remarkable decrease in the impedance between the aluminium electrode and the solution is observed in the potential region of pitting dissolution. Since the impedance of the surface film itself dose not show a remarkable change, the above decrease in impedence is dominated by the Faradaic impedance induced by the pitting dissolution current.
  • 大野 篤美, 早田 博
    1969 年 33 巻 9 号 p. 1049-1052
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    To provide sufficient evidence as to the mechanism of grain refinement of Al, Al-0.04%Ti alloy was solidified in a mold equipped with a horizontal barrier, by which a zone of very fine grains was found to exist only on the barrier and not under it. This is considered to be inconsistent with the nucleating agent theory and the peritictic reaction theory. When Al-0.15%Ti alloy was poured into a graphite mold at 750°C, very fine grains were obtained. The grain size increased markedly as the pouring temperature was increased to 900°C. However, the grains became refined when the molten surface was agitated during solidification. The mechanism of the grain refinement is considered to be dendrite remelting due to the temperature fluctuations in the mold in the early stage of solidification. It appears that solid particles, such as TiC, which have been considered as the nucleant of crystallization are trapped in the crystals by dendrite arms during solidification.
  • 大野 レイ一
    1969 年 33 巻 9 号 p. 1053-1059
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The solution rate of solid iron in liquid copper was studied under dynamic conditions. A cylindrical iron was rotated in liquid copper or liquid Cu-Fe alloys for 40 to 240 sec at about 240, 560 and 820 revolutions per minute at about 1220°, 1300° and 1380°C. The dependence of the solution rate on the iron concentration in liquid copper was investigated. Its dependence at the highest temperature can be explained neither by the Berthoud equation nor by Lommel and Chalmers’ equation, but approximately by an equation in which the driving force is expressed by the difference in the activity of solute between saturation and bulk liquid. A theoretical derivation of the new equation was tried and a consideration was made from the standpoint of thermodynamics of irreversible processes. The solution rate constant defined by the equation increases with increasing temperature and rotational speed. The dependence of the logarithm of the solution rate constant on the reciprocal of absolute temperature gives the activation energy ranging from 40 to 47 kcal/mol. The exponent of Reynolds numbers determined from the dependence of the solution rate constant on the peripheral velocity of rotating cylinder ranges from 0.5 to 0.7.
  • 中山 忠行, 押田 良機
    1969 年 33 巻 9 号 p. 1060-1066
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The present authors have studied the structures and chemical compositions of the oxide films produced on the surfaces of 18-8 and 18Cr stainless steels, in 300°C water and vapor under various polishing conditions. Especially, the effects of the oxidation duration, polishing conditions and dryness of the vapor on the structures and chemical compositions of the oxides were investigated through the electron microscope, transmission electron diffraction and the X-ray microanalyzer.
    The main results obtained are as follows:
    (1) The corundum type oxide produced on the surfaces by mechanical polishing at 300°C for 1 hr is identified to be (Cr, Fe)2O3 alone or its coexistence with α-Fe2O3. The corundum type oxide has been transferred to the spinel type oxide containing Ni with prolonged heating time (24 hr). This spinel type oxide is presumed to be formed by the solid reaction of NiO with (Cr, Fe)2O3 and/or α-Fe2O3.
    (2) The oxide films formed on the chemically and electrolytically polished 18-8 stainless steels were the spinel type oxides having Ni.
    (3) After the heating in high temperature vapor (dryness: 0.18) of 18-8 stainless steel, the corundum type and spinel type oxides were found on both the mechanically and chemically (or electrolytically) polished surfaces. In the case of the higher dryness (1.0), however, the structure difference by the polishing conditions was not observed; i.e., the corundum type oxides were detected on the three differently polished surfaces.
    (4) On heating in the high temperature water and vapor of 18Cr stainless steels under the same conditions, the oxide films were of the corundum type containing Fe and Cr. This evidence throws a light on the contribution of Ni to the formation of spinel type oxides detected in the initial oxide films of 18-8 stainless steel.
  • 堀 真市
    1969 年 33 巻 9 号 p. 1067-1072
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The β→α+γ2 transformation of Cu-Al binary alloy is depressed at cooling velocity 5°C/min and changes to β→β1 and β1→β′ transformations. The tempering processes of the alloy show combinations of β′→β1, β1→α+γ2, β1→β, β→α+γ2 and α+γ2→β transformations, depending on the tempering conditions. In this paper, the effects of Fe and Zr on cooling and tempering eutectoid transformations and on the self-annealing of Cu-Al binary alloy were measured by means of differential dilatation, differential thermal analysis and microscopic observation. The changes in the length of the columnar structure with the β′→β1 transformation were also discussed. The results obtained were as follows: (1) Some columnar structures of Cu-12.2Al, Cu-12.3Al-1.2Fe and Cu-12.5Al-1.2Zr alloys contracted at β′→β1. (2) The β→α+γ2 transformation temperature of Cu-12.3-1.2Fe alloy was lower than Cu-Al binary alloy and that of Cu-12.5Al-1.2Zr alloy was higher. (3) The processes of cooling and tempering transformations of Cu-12.3Al-1.2Fe, Cu-12.5Al-1.2Zr alloys were the same as those of Cu-Al binary alloy, but microstructures of Cu-12.7Al-1.0Fe, Cu-12.7Al-0.7Fe, Cu-12.5Al-1.2Zr and Cu-12.4Al-0.7Zr alloys water-quenched from 800°C were β′+γ′ produced by phase separation. The Al concentrations in these alloys were lower than those in the Cu3Al type lattices. (4) The self-annealing of Cu-Al binary alloy was depressed by adding Fe and enhanced by adding Zr.
  • 堀 真市
    1969 年 33 巻 9 号 p. 1073-1077
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The effects of Cr and Ti on cooling and tempering eutectoid transformation and on the self-annealing of Cu-Al binary alloy were measured by means of differential dilatation, differential thermal analysis and microscopic observation. The results obtained were as follows: (1) The β→α+γ2 transformation temperature of Cu-11.6Al-1.5Cr was higher than that of Cu-Al binary alloy and that of Cu-12.1Al-1.6Ti was lower. (2) The processes of cooling and tempering transformations of Cu-11.6Al-1.5Cr and Cu-12.1Al-1.6Ti alloys were the same as those of Cu-Al binary alloy, but the microstructures of Cu-12.6Al-1.2Cr and Cu-12.7Al-1.4Ti alloys water-quenched from 800°C were β′+γ′ by phase separation and the Al concentrations in these alloys were lower than in the Cu3Al type lattice of these alloys. (3) The self-annealing of Cu-Al binary alloy was enhanced by adding Cr and Ti.
  • 西田 和彦
    1969 年 33 巻 9 号 p. 1077-1083
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    The effect of austenitizing temperatures of 900°C to 1250°C and isothermal holding at 900°C after the solution treatment at 1250°C on the mechanical properties of a Nb-bearing carbon steel were studied. Electron microscopic observations by the replica method, optical microscopic observations and analysis of Nb contents in the residues extracted by 1:1 HCl were carried out on some of these specimens. The results obtained are as follows:
    (1) The tensile strength after air cooling increases with increasing austenitizing temperature above 1100°C. This probably is the result of strengthening of the ferrite matrix due to the precipitation of fine NbC(N).
    (2) The tensile strength of Nb-steel decreases sharply with increasing holding time at 900°C after the solution treatment and reaches nearly the same strength as the strength of C-steel. This variaiton in tensile strength corresponds well to the Nb content in the residues extracted by 1:1 HCl. The localized distribution of NbC(N) suggests that the precipitation occurred at the original austenite grain boundary, twin boundary, stacking fault or dislocation. Retempering of the steel which became nearly the same strength as C-steel shows no secondary hardening between 500°∼700°C and decreases with increasing tempering temperature.
    The above results suggest that the Nb dissolved in solution over the austenitic range precipitates during or after transformation as fine NbC(N) precipitates coherent with the ferrite matrix and contribute to the increase in tensile strength.
  • 柳原 正, 小林 剛, 福田 豊
    1969 年 33 巻 9 号 p. 1083-1086
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    It was previously reported that the hydrogen-reduction product of Fayalite was the iron crystals surrounded with the silica crystals, having no Si-O-Fe-O-Si bond. The extraction of Fe from Fayalite with HCl is much easier than from the hydrogen-reduction product. 100% of Fe was extracted from Fayalite with boiling 6 N HCl, while only 85% of Fe was extracted with boiling 6 N HCl from hydrogen-reduction product.
    Both residues were examined with the X-ray diffraction method: The residues of the hydrogen-reduction products show the decrease of α-Fe alone with the advance of the extraction process, leaving a small amount of α-Fe and amorph silica as residues at the later stage of extraction. The residues of Fayalite show the decrease of orthorhombic Fayalite in the early stage.
    In later stage of extraction, the X-ray diffraction patterns of a cubic Fayalite spinel-like substance appeared. When extracted all of Fe in Fayalite, no diffraction patterns were detected. About residues of HCl extraction with two series of samples, the infra-red absorptions were measured. Residues of the H2-reduced product showed only the infra-red absorption of SiO2 in the early stage, and in later stage the absorption due to the hydration of SiO2 appeared together with the absorption of SiO2.
    In the case of the residues of Fayalite, with the advance of the HCl extraction process, the absorption of orthorhombic Fayalite disappeared, but that of SiO2 with OH-bond appeared.
    No absorption of the cubic Fayalite spinel was detected. The process of the Fe2+ extraction in the orthorhombic Fayalite with HCl has been discussed to account for the formation of fine colloidal silica.
  • 依田 連平, 新井 隆
    1969 年 33 巻 9 号 p. 1087-1092
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    Molybdenum was coated with a JIS electric heating material (Nichrome alloy) and cobalt-base heat-resistant alloy (S-816) by casting and was then drawn to a diameter of 0.5 mm. On the applicability of these wires to the electric heating wire, some properties which are required for electric heating wire were compared with the commercial JIS electric heating wires, Ni, Cr and Ni-Cr multi-electroplated molybdenum wires and Al and Al-Si alloy dipped molybdenum wires. The life of the composite material is equal and/or superior to the JIS Nichrome wire up to 1250°C, but deteriorated at 1300°C. The tensile strength of the material is almost equal to the JIS electric heating wires at room temperature, but about 2 to 2.5 times larger at 1200°C. The electrical resistivity of the material is considerably small as compared with the JIS electric heating wire at room temperature, but becomes almost equal at 1000°C because of its high temperature coefficient. The change in electrical resistivity of the material after its use for a long period is almost equal to the JIS electric heating wire. This result shows that the material is very stable. In conclusion, this composite-material shows an ability comparable to the JIS electric heating wire in air up to 1250°C and is advantageous for a particular purpose in view of its superior high temperature strength.
  • 榊 隆
    1969 年 33 巻 9 号 p. 1092-1098
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
    An extraction spectrophotometric method with sulfochlorophenol S for the determination of niobium was investigated, and applied to the determination of niobium in iron and steel.
    The niobium sulfochlorophenol S complex is formed quantitatively in 1.2∼2.4 N, hydrochloric acid media, and this complex is quantitatvely and easily extracted with n-butyl alcohol in the presence of diphenylguanidine. The absorption maximum of the extracted complex is at a wavelength of 650 milli microns.
    Iron, molybdenum and zirconium interfere with the determination of niobium, but these interferences can be eliminated to some extent by the use of thioglycollic acid and EDTA. The presence of sulfates of chromium and nickel lowers the absorbance for the determination of niobium; the coexistence of more than 2 mg each of chromium and nickel and of more than 0.5 mg of chromium and 1 mg of nickel interfere with the determination of 10γ and 20γ of niobium, respectively.
    The addition of more than 0.5 mL of sulfuric acid (1+10) in the presence of 0.5 mL of phosphoric acid (1+10), lowers the absorbance for the determination of 20γ of niobium.
    The sample was fumed with a mixture of sulfuric and phosphoric acids for dissolving completely the carbides and tungstic acid after the sample was dissolved in aqua regia.
    As a result of the present experiment, the author succeeded in establishing a method in which 0.01 to 2% niobium contained in iron and steel can precisely be measured without difficulty.
  • 1969 年 33 巻 9 号 p. 1098
    発行日: 1969年
    公開日: 2008/04/04
    ジャーナル フリー
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