応用物理
Online ISSN : 2188-2290
Print ISSN : 0369-8009
ISSN-L : 0369-8009
26 巻 , 6 号
選択された号の論文の14件中1~14を表示しています
  • 青木 昌治
    1957 年 26 巻 6 号 p. 215-228
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
  • 坂田 亮
    1957 年 26 巻 6 号 p. 229-233
    発行日: 1957/06/10
    公開日: 2009/02/20
    ジャーナル フリー
    Gold beads of equal sizes are sintered in a small cylindrical vessel under Compressive load. The relations among the diameter of bead, load, sintering time and the lowest sintering temperature (the temperature for the beginning of sintering) are determined by the method described in the former report1). The diameters of beads tested are 1.35, 0.85 and 0.45mm. For example, the beads (0.85 mm in dia.) are sintered at 413°K for 5 minutes under a load of 3.5kg or at 1203°K for 5 minutes under no load. These temperatures are 30 and 90% of the melting point of gold respectively. The value of ξ=(-dlog TS/dlog W)r, t=const changes with the lowest sintering temperature Ts, where ξ is the rate of lowering of the lowest sintering temperature with the increase of load under the same sintering time and radius of beads. In the case of 0.85 mm in diameter, the value of ξ has a maximum value at a little higher temperature than the range of the recrystallization temperature of gold (100°_??_400°C).
    The ratio of the diameter of the adhered area between two beads to the diameter of the bead is found to take a certain value, 7%, independent of the dimension of the bead under no load, but it becomes larger with the load. In the case of 0.85 mm in diameter, it is 7_??_10 between 0_??_100g in load and 10_??_54% between 100_??_3500 g in load.
    The activation energy for beginning of sintering between two beads is found to take a certain value regardless of the dimension of the bead, but it changes with the lowest sintering temperature. It becomes smaller with the sintering temperature, but has a minimum value within the range of recrystallization temperature and then it becomes larger. Its minimum value is about 18 kcal/mol and the largest value is 290 kcal/mol. These values are 1/3 and 6 times as large as the activation energy of self-diffusion of gold respectively.
  • 田中 栄, 安斉 太郎
    1957 年 26 巻 6 号 p. 234-238
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
    The results of laboratory and field experiments on the propagation of ultrasonic pulses in concrete are reported. The data obtained are believed to be useful in measuring the dynamic elastic constants and Poisson's ratio of concrete structures of dams in particular. Langevin type vibrators of barium titanate ceramic, with the resonance frequency of 21 Kc/e are found most suited as the sending and the receiving units for the purpose. The main results of the fields tests are as follows:
    In concrete dams, it is possible to measure the compressional waves and the surface waves separately, so that the Poisson's ratio can be computed from the measured values. The transverse waves can be observed when the sending and the receiving units are in particular relative positions and angles. The propagation waves are accompanied by secondary waves of frequencies far lower than the natural frequency of the sender, and the propagation of the surface waves through long distances is found to depend chiefly on such secondary waves. This shows the importance of the secondary waves for which the data obtained by fundamental experiments are given in addition.
  • 谷崎 茂俊
    1957 年 26 巻 6 号 p. 238-241
    発行日: 1957/06/10
    公開日: 2009/02/20
    ジャーナル フリー
    WO3 is monoclinic at a room temperature and has a domain structure with walls of (110) and (100) twin planes. (110) wall is displaced vertically by a unidirectional pressure externally applied along b-axis with the change of axis b to shorter axis a. (100) domains change to a single domain by stress Xz. Single domain crystal obtained by this method is used to determine the optic elasticity axes of WO3. Two peculiar types of domain structure appear by a pressure along c-axis, which can be understood as a result of the change of axes c _??_ a by the stress. The sensitivity of domain structure to the stress thus witnessed seems to be due to the pseudosymmetric structure of WO3 crystal.
  • 椙山 一典, 湯浅 一経
    1957 年 26 巻 6 号 p. 242-246
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
    Characteristics of ZnS(Ag) phosphor for a-particle detection are described. Investigations are made on some commercial ZnS (Ag) for (a) the preparation of phosphor screen, (b) the relation between photomultiplier voltage and counting ratio using screens of varying thicknesses, (c) the relation of thickness vs. counting efficiency, (d) the effect of thickness on pulse height distribution of Po-α particles and (e) the effect of activator Ag content. Also, (a) comparison with other phosphors, (b) application to T (d, n) He 14 MeV neutron monitor and (c) application of fast decay component to fast coincidence, are tried.
    It is found that the grain size and screen thickness are important, as ZnS(Ag) phosphor is in powder form and is opaque to its own fluorescent light.
    Desirable result for a-particle detection is obtained with high backgrounds of γ-rays and neutrons.
  • 岡部 茂, 北本 篤義
    1957 年 26 巻 6 号 p. 247-249
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
    A direct measurement method to study the distribution of a-particles in air near the ground surface has been deviced using nuclear plates.
    The instrument consists of some nuclear plate cameras, a suction pump and rubber tubes which are connected to each camera. The sample air is introduced into the camera through the rubber tube supported at a appropriate height. After some hours of suction the number of tracks of α-particles on the nuclear plate are counted. Results seem to show no agreement with the theoretical presumptions of recent investigators.
  • 吉村 正夫
    1957 年 26 巻 6 号 p. 250-253
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
    The possibility of roughness of surface being measured by means of jelly containing radio isotope is confirmed. The jelly is spread over the surface, scraped flat with a straight edge under predetermined conditions, dried and the count by radiation counter is taken, The count is proportional to what the author calls the mean 3-dimensional roughness determined by the amount of jelly that filled up and smoothened up the unevenness. The results are compared with the roughness measured with electrical capacitance method.
  • 小倉 磐夫
    1957 年 26 巻 6 号 p. 254-259
    発行日: 1957/06/10
    公開日: 2009/02/20
    ジャーナル フリー
    The extension of the image of a point source formed by any optical system is practically limited to some finite area in the image plane. As a consequence the sampling theorem can be applied to the plane of the exit pupil. The process is the counterpart of the sampling theorem applied to the image plane. The case of optical system with spherical aberration only is studied.
    It is shown mathematically that, if the Fourier spectrum G (R) of a two dimensional radial function g(r) contains no frequency higher than 1, then g(r) is expanded in the series of _??_ with the coefficient gs), where μs is the s-th root of the Bessel of _??_J, with the coefficient gs), where μs is the s-th root of the Bessel function of order zero, and the spectrum G (R) is completely determined by giving a discrete set of g (p). If we represent by G (R) the complex amplitude of the image in a limited area, g (r) corresponds to the pupil function, and the former can be expressed by a set of gs). As an example the intensity of the image is calculated for a lens with spherical wave aberration of 3/4 λ.
  • 小川 智哉
    1957 年 26 巻 6 号 p. 259-266
    発行日: 1957/06/10
    公開日: 2009/02/20
    ジャーナル フリー
    周波数分析器の濾波素子として広く用いられている圧電結晶共振子(piezo-electric resonator)は,圧電結晶を適当な方位に切り出して作つた振動子が,それの弾性的共振点近くで電気的インピーダンスが大きく変ることを利用したもので,現在では水晶のAT, BT, CT, NTカット等が多く用いられている.
    ところで,振動子が弾性的共振を起すと振動の節の部分には非常に大きな歪が生ずるが,この歪に依る光学的異方性(光弾性効果)を偏光を用いて光電管,写真又は肉眼等で検出すれば,その透過光量から振動子の共振の有無強弱がわかるから,このような共振子を並列に幾つか使用して,直視型の周波数分析器にすることが出来る.
    このように共振の様子を直ちに光学的に検出する共振子(piezo-optic resonator)を作るには,透明で,圧電定数,光弾性定数及び機械的Q値の三数の積が大き圧い電結晶が必要である.このような条件を満足する結晶の一つは, ADP結晶である.
    ADP結晶というのは,第一燐酸アンモニウム(ammonium dihydrogen phoshate: NH4H2PO4)の結晶で正方晶系D2dに属し(Fig. 1),水溶液から育成されるが,結晶水を含んでいないので風解せず,又潮解も湿度90%以上にならないと起らない.しかもロツシェル塩のように室温で強誘電的でなく, -100°Cから+100°C位の湿度範囲で安定で,圧電定数,電気機械結合係数及び電気光学定数が大きいので,音響素子やKerr Cell等として種々の機器に用いられている1) 2) 3) 4).このような長所と相俟つて,最近我国でもADP結晶の工業的育成が行なわれ,結晶の入手及び加工が容易となつた.
    そこでADP結晶の45°zカットで短冊型振動子(longitudinal vibrationをする)を作り,それの性質について調べた結果,この共振子のQ値は500~1,000で末だ良好とはいえなかつたが,数十ボルトの電圧で共振させれば,容易に共振を肉眼で検知し得る程度の光量変化があつた.従つてこのような共振子を数箇並列に使用して,簡単な直視型音響分析器が出来る見透しが得られた5).
  • 嵯峨 卓郎, 佐藤 金司, 井坂 昌夫
    1957 年 26 巻 6 号 p. 267-268
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
  • 神山 雅英
    1957 年 26 巻 6 号 p. 268
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
  • 西野 治
    1957 年 26 巻 6 号 p. 269
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
  • 菅 義夫
    1957 年 26 巻 6 号 p. 269a
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
  • 川崎 弘司
    1957 年 26 巻 6 号 p. 269b
    発行日: 1957/06/10
    公開日: 2009/02/09
    ジャーナル フリー
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