材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
23 巻 , 250 号
選択された号の論文の16件中1~16を表示しています
  • 荒川 正文
    1974 年 23 巻 250 号 p. 504-514
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
  • 高坂 彬夫, 菊池 正志, 長谷川 二男
    1974 年 23 巻 250 号 p. 515-519
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    A study has been carried out on the physico-chemical properties of Itaya-zeolite, one of the most important natural zeolites of this country. The properties studied were chemical composition, shape, structure, specific surface area, pore volume distribution, gas adsorption, etc.
    The following facts were brought to light about Itaya-zeolite.
    (1) It is composed mostly of clinoptilolite, containing some mordenite.
    (2) Its structure changes when heated at temperatures above 700°C.
    (3) The amount of H2O, NH3, H2S or SO2 adsorbed on the natural zeolite is about 60 weight % of that by synthetic zeolite (3A∼5A).
    Being far less expensive than synthetic zeolite, Itaya-zeolite will be used as the adsorbent for various kinds of gas as well as for water vapour.
  • 海保 守, 栗原 現司, 近沢 正敏, 金沢 孝文
    1974 年 23 巻 250 号 p. 520-524
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    As a part of the hygroscopic studies of powder mixtures, the behavior of NaCl-K2SO4 mixtures in a water vapor adsorption process were investigated.
    The mixing of the two salts was carried out in vacuo. The water vapor adsorption isotherms of NaCl, K2SO4 and their mixtures were determined. The surface areas and X-ray diffraction intensities of the mixed salts were measured under various water vapor pressures.
    At the relative water vapor pressures above 0.34 on NaCl and 0.65 on K2SO4, water adsorbed on these salts was released partly owing to the decrease in the surface area of the salts. This decrease in the surface area may be attributed to the combination of the following two factors; the aggregation of the powder particles due to the cohesion force of the adsorbed water and the dissolution-deposition effect between the particle surface and the adsorbed water layers.
    Both the surface area and the water vapor adsorption capacity of the mixed sample began to increase when the sample was pretreated at the relative vapor pressure above 0.34. The X-ray diffraction data of the mixtures indicated that NaCl reacted with K2SO4 in the presence of water adsorbed as follow:
    NaCl+K2SO4→KCl+(Na, K)2SO4
    The increase in the surface area of the mixed sample seemed to be caused by deposition of micro-crystals formed by the reaction. The minimum thickness of the adsorbed water required to cause the above reaction was determined to be 2.0 and 1.3 molecular layers for NaCl and K2SO4, respectively.
  • 山口 喬, 箱守 正和
    1974 年 23 巻 250 号 p. 525-530
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    Decomposition of coprecipitated (Cr-Al) hydroxides was studied with special emphasis on the crystallization and composition of the corundum type solid solution.
    Temperature of crystallization of the corundum phase increased with increasing Al content. The corundum phase contained higher Cr/Al ratio than in the starting coprecipitate for all the compositions studied, though more Al was accommodated with increasing temperature.
    It was shown that at least 1300°C is necessary to obtain a homogeneous solid solution with the Cr/Al ratio equivalent to that in the coprecipitate.
    The comparison of the decomposition experiments for the aged and non-aged coprecipitates indicates that boehmite produced by the aging of coprecipitates accelerates the crystallization of the corundum phase.
    Considerable compositional deviation of corundum phase from those in the available phase diagram is explained as due to the difficulty in getting an equilibrium state. This point of view is supported by the results of prolonged isothermal heating of coprecipitates.
  • 早川 宗八郎, 長岡 輝治, 阿部 勝彦
    1974 年 23 巻 250 号 p. 531-535
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The purpose of this work is to get some information on the correlation between the change in crystal structure of atomic long-range order and that in crystal field of short-range order during mechanochemical processes. The x-ray diffraction patterns and the fine structures of fluorescence spectra from doped Sm ions were observed on several TiO2 crystals which were prepared by various procedures. TiO2(Sm) of anatase type changed to that of rutile type by grinding. The fine structure of spectrum changed from anatase to rutile almost in parallel to the corresponding change in x-ray pattern. It shows that no essential difference exists between the long-range reordering and the short-range reordering during the mechanochemical phase change. The broadening of fine structures of spectra, however, was observed in neither well ground TiO2(Sm) nor amorphous TiO2 fired at temperatures lower than the crystallization temperature. Such amorphous phase of TiO2 is considered to have a definite crystal field due to the ionic surrounding having the short-range order. This seems quite different from usual inorganic glasses, which give fluorescence spectra with broad structures from doped Sm ions.
  • 竹内 学, 金子 冨士男, 長坂 秀雄
    1974 年 23 巻 250 号 p. 536-540
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The effects of ball milling on the photoconductivity process in ground CdS powders were investigated. A sample powder was prepared from aqueous solution of cadmium sulphate. The powder was found to have a hexagonal structure, and the mean particle size was about 10μm. The powder was ground in an alumina ball mill for different periods from 30min to 30hr, In the early stage of the grinding process, the mean particle size decreased rapidly to about 2μm and it did not decrease any more even if grinding time was increased.
    The X-ray analysis showed the following results: (1) The transformation of CdS from hexagonal to cubic does not take place during grinding by using the alumina ball mill. (2) The degree of lattice distortion increases with increasing grinding time.
    Reflectance of the ground CdS powders decreased slightly with grinding time in the wavelength region of 550∼700nm. This reduction could be explained by an increase in lattice distortion.
    Using an interdigital electrode, the spectral response of photoconductivity, the photocurrent-light intensity characteristic and the decay of photocurrent were measured for the ground CdS powders. The photocurrent decreased considerably in the early stage of the grinding process, and then decreased gradually with increasing grinding time. This change was similar to the change of the mean particle size with grinding time. As the result of this similarity, it became evident that the considerable decrease in photocurrent by grinding is atributable to an increase in interparticle contact resistance of pressed CdS powders.
    The photoconductivity spectral response of the ground CdS powders showed a larger decrease in the short wavelength region than in the long wavelength region. This could be explained by structural imperfections generated near the CdS surface. The imperfections generated by grinding acted as the recombination centers and lowered the photosensitivity, especially in the short wavelength region. It was found also that the recombination centers facilitated the decay of photoconductivity. Moreover imperfections could also act as the trapping centers and lower the speed of response.
  • 宇津木 弘, 堀越 英生, 松沢 敏晴
    1974 年 23 巻 250 号 p. 541-548
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The silica gels containing two different surface groups were obtained through the surface-treatment of silica gels with the mixtures of two kinds of alcohol or of alcohol and phenol in autoclave. The quantitative determination of their component surface group was performed from their infrared absorption spectra, since the carbon contents of the component surface group can be reasonably determined in comparison with the total carbon contents from elemental analysis by using Lambert-Beer's law and the ratio of the absorbancy of the respective characteristic absorption of surface group against the absorbancy at 800cm-1 due to skeltal vibration of _??_Si-O-Si_??_. The argon surface area of surface-treated silica gels was discussed on the basis that the area covered by each surface group was constant for the silica gel prepared under the same condition. The silica gels pretreated with n-octanol were treated furthermore with methanol or benzyl alcohol. The former showed only the simple increase of numbers of the methyl group, whereas the substitution of the n-octyl group to the benzyl group was observed in the latter. Thus this reaction was regarded as the transesterification of the surface esters.
  • 梅屋 薫, 磯田 武信, 原 隆一, 菊田 潤一
    1974 年 23 巻 250 号 p. 549-554
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The angle of internal friction is one of the most important properties of powder and is often used to characterize powdered materials. The angle of internal friction has been generally determined from the slope of yield locus in the previous works. However, it has been reported also in many papers that the shape of yield locus is affected by the external conditions and the properties of the powder particles. Thus the angle of internal friction has not been determined precisely. On account of this reason, it is necessary to consider the shape of yield locus before everything. In this paper, the shape of yield locus was studied to know its dependence on some factors by analysing the mechanisms of the shear test.
    The shear test was performed using plastic balls of amorphous polystyrene as the powder, of which viscoelastic property changes with temperature continuously. The yield loci were determined at several temperatures and preconsolidation pressures. The results obtained show that the values of shear index determined from the yield loci, which is the reciprocal of the shear index in Warren Spring's equation, change with temperature and preconsolidation pressure. Furthermore it is seen that the influence of preconsolidation pressure can be substituted by the influence of temperature. As the results, the master curve of shear index vs. preconsolidation pressure could be constructed.
    On the other hand, it is considered that the shearing property is affected by the state of packing, which is dividable into the four parts-plastic deformation, elastic deformation, reversible rearrangement and irreversible rearrangement. It can be concluded that the change of shear index is determined by the values of these four contributions.
  • 1974 年 23 巻 250 号 p. 554-556
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
  • 1974 年 23 巻 250 号 p. 557-563
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
  • 浅見 克敏, 寺沢 正男
    1974 年 23 巻 250 号 p. 564-568
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    In the previous study, the authors proposed the following prediction equation on the fatigue limit of the smoothed specimen made of tufftrided steel, and clarified the validity of the equation from the experimental data.
    σw·t={C1(h/a-h)+(1+C2)}σw·nt
    Where, σw·t: fatigue limit of tufftrided specimen
    σw·nt: fatigue limit of non-tufftrided specimen
    h: hardened depth
    a: distance from the surface to the center of specimen
    C1: a constant which indicates the hardening due to cyclic stress
    C2: a constant which indicates the degree of improvement of fatigue limit due to residual stress
    In this paper, the authors describe the results of the fatigue tests on specimens with various a and h, and discuss the limitation of the applicability of this prediction equation from the experimental data.
    The results of the discussion are summarized as follows:
    (1) The applicable range of the equation is 0.01≤h/(a-h)≤0.6, when the material is 0.15% carbon steel and the rotating bending stress is applied.
    (2) In case of h/(a-h)<0.01, the fatigue limit is hardly improved.
    (3) In case of h/(a-h)>0.6, the improvement of fatigue limit is saturated.
  • 井上 貞弘
    1974 年 23 巻 250 号 p. 569-574
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The bond strength development of epoxy resins was investigated by means of the shear and tensile bond strength methods. All the experiments were conducted in a low temperature laboratory controlled, at 4°C, 70per cent R. H.
    Firstly, the shear bond strength method of JIS K 6801 using birch timber of edge grain was applied. The moisture content of the adherent was of 6 kinds ranging from 10 to 106per cent, and the hardening time was of 4 kinds ranging from 1 to 8 days. The results were: (1) Water does not have so much deteriorating effect on the bond strength development of epoxy resins as on that of a polyvinyl acetate emulsion adhesive or an urea resin adhesive, (2) with epoxy resins a greater strength development is obtained at a smaller moisture content of wood, and (3) the usable range of moisture content of wood is under 32per cent with epoxy resin No. 1 and under 10per cent with epoxy resin No. 3, while epoxy resin No. 2 is not suitable for the purpose of adhesion of wood.
    Secondly, the tensile bond strength method using cement mortar briquette of ASTM C 190 was applied. The water content was of 5 kinds ranging from 3.2 to 8.0per cent, and the hardening time was of 3 kinds ranging from 1 to 4 days. The results were: (1) Water does not have so much deteriorating effect on the bond strength development of epoxy resins as on that of polyvinyl acetate solution adhesive, (2) with epoxy resins a greater strength development is obtained at a smaller water content of cement mortar, and (3) in case of the adhesion of finishing materials, the usable range of water content of cement mortar is under 8.0per cent with epoxy resins No. 1 or No. 2, while in case of the adhesion of structural materials, the usable range of water content of cement mortar is under 7.3per cent with No. 1 and under 3.2per cent with No. 2.
  • 藤谷 景三, 元津 彰夫
    1974 年 23 巻 250 号 p. 575-580
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    As a new method to predict the fatigue lives of metallic materials under the fatigue tests with multiple repeated loads or strains, the fatigue fracture criterion based on varying plastic strain amplitudes instead of the linear damage criterion. Σ(n/N)=1 has already been. verified experimentally by carrying out the low-cycle fatigue tests under tension-compression and rotating bending. However, for the plane bending and torsional fatigue tests it has not been verified so far experimentally whether the fatigue fracture criterion based on varying plastic strains is applicable or not. From such a view point, the authors have carried out the lowcycle torsional fatigue tests by using 0.84%C piano wires under multiple repeated strains, and investigated the applicability of the fatigue fracture criterion based on varying plastic strains experimentally. Furthermore, the applicability of the above fracture criterion has been also discussed on the basis of the experimentally determined correlation between the equivalent stress τeq and the equivalent plastic strain amplitude γp.eq.
    The main results obtained are summarized as follows:
    (1) The values obtained from the fatigue fracture criterion based on varying plastic strains were slightly closer to unity than those calculated from the linear damage criterion. Therefore, when used for predicting the fatigue lives under the strain control test, the fatigue fracture criterion based on varying plastic strains is better than the linear damage criterion.
    (2) From the test results the following exponential relationships were found to hold between the equivalent stress and the equivalent plastic strain amplitude.
    γp.eq=c·aτeq up to fracture,
    γp.eq'=c'·a'τeq' up to fracture initiation,
    Where a, a' and c, c' are constants.
    (3) The strain ratio γa2a1 or the number of cycle ratio n2/n0 had a little effect on the cumulative damage in this study.
  • 網島 貞男, 谷本 敏夫
    1974 年 23 巻 250 号 p. 581-587
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    Fatigue tests have been conducted to investigate the fatigue properties of glass fiber reinforced plastics, especially the effects of environmental temperature and volume content of glass fiber in the specimen.
    The materials used were two kinds of F. R. P. laminate consisting of the same kind of matrix but different types of reinforcement, satin woven and plain woven fabrics.
    Sufficient data have been obtained to produce the master diagrams for both types of laminate. The Goodman law and the Gerber law are being commonly used to clarify the relation between mean stress and stress amplitude. However, the results of our experiments show that these laws are not applicable for F. R. P. at higher testing temperatures than room temperature. Then, an empirical equation in the form of modified Gerber law showing the relationship between the mean stresses and the stress amplitudes at various lives is proposed.
  • 山口 章三郎, 大柳 康, 辻川 洋三郎, 高橋 義男
    1974 年 23 巻 250 号 p. 588-592
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
    The effects of dimensions and supporting conditions on the compressive strength and deformation of polyvinylchloride pipes under external pressure were discussed. The following four kinds of pipe supporting conditions were used; (A) compression between two steel plates, (B) compression between a steel plate and a concave wooden block, (C) compression between two concave wooden blocks, and (D) compression between two concave hard rubber supporters. The main results obtained are as follows.
    (1) The relation between the compressive strength P and the dimensions of PVC pipe is given by the following formula, similar to the mid load bending for a both end fixed straight beam with a rectangular section;
    P=4σb·l·t2/3·Dm·c1 (a)
    where, l, t and Dm are the length, thickness and diameter of pipe, respectively, c1 the correction coefficient according to pipe supporting conditions, and σb the bending stress in kg/mm2. The value of correction coefficient c1 was 0.81∼1.35 for A-method, 1.35 for B-method, 8.0 for C-method and 2.3 for D-method, respectively.
    (2) The deflection δ under elastic deformation is given by the following formula;
    δ=P·Dm3/8E·l·t3c2 (b)
    where, E is Young's modulus in kg/mm2 of pipe material, and c2 the correction coefficient similar to c1. The value of c2 was 2.22 for A-method.
    (3) It seems reasonable, therefore, that the theory of straight beam may be applied to the compressive strength and deflection of plastics-pipe under external pressure by using the correction coefficient c1 or c2.
  • 小寺沢 良一
    1974 年 23 巻 250 号 p. 593-601
    発行日: 1974/07/15
    公開日: 2009/06/03
    ジャーナル フリー
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