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回転円板の振動
Get PDF論文(Article)The Vibrations of a rotating circular plate are very important ploblem in Engineering. The difficulties of an exact solution for the equation of motion have developed some approximate methods. For example, Southwell published the very interesting paper in 1922. He analyzed this ploblem by treating the two following cases separately, (1) considering only the flexural rigidity (2) neglecting the flexural rigidity and considering only the effect of centrifugai force. In this paper, we treat the transverse vibrations of a circular plate of uniform thickness rotating about its axies with constant velocity. The circular plate is clamped with inner circle, having the uniform load on the outer circle. We solve this problem by Ritz's method and Galerkin's. The Lagrangian consists of three energies, (1) works by centrifugal force, (2) kinetic energy of a disk, (3) strain energy of a disk. We assume the deflection of a circular disk as a linear series of the admissible functions, and obtain the frequency equations adjusting the arbitrary coefficients in the series so as to minimize the Lagrangian. Considering the amount of calculations and their accuracy, Ritz's method is more convenient than Galerin's in this case. So we treat the all by Ritz's method. The experiments are carried out and their results are compared with theoretical ones
鋼の降伏に関する研究
Get PDF論文(Article)The mechanism of yielding phenomena in carbon steel has been recently considered from the standpoint of dislocation theory, but these phenomena peculiar to carbon steel can not be explained satisfactorily by this theory alone. These phenomena are affected by the change of phase which occurs by various heat treatments and the addition of other elements. We measured the thermal change of carbon steel in its tensile test. As a result, endothermic change appeared below the yield point and exsothermic change on the yield point. The amount of this endothermic change is as mush greater than that which is due to the elastic deformation measured by Tammann. The endothermic change is caused by the dissolution of the compounds of carbon and nitrogen in the part of lattice defects into matrix, and then the specimen softens as the effect of this change. Luders line appears when the strength of the part of lattice defects become to be identical with that of complete lattice, and then hardness increases according to the occurence of slip. Strain ageing occurs owing to reprecipitation of the particles by ageing after removing stress
小型におい測定装置の開発
Get PDF論文(Article)A thin film of Urushi or Cashewnut toluene extract was coated on the surface of AT cut piezoelectric quartz crystals. The sensitivity of 8.9MHz quartz crystal is l0-9g/△ lHz for fragrance materials. This quartz sensor led to the development of a small-size fragrance-measurement apparatus. Sensitive detection measurements of fragrance adsorption on porous materials were carried out as an example of applicability of this apparatus
ジェット粉砕における粉砕産物の増加比表面積に及ぼす諸因子の影響
Get PDF論文(Article)The effect of various factors on specific surface area produced was experimentally investigated by means of the jet mill which had been reported in the previous paper. Six kinds of samples -- limestone, marble, gypsum, feldspar, quartz and beer bottle glass -- wTere used in this experiments. The specif1c surface area produced was found to increase with - 0.25 power of feed rate and to be proportional to the total air rate through all nozzles. Grinding ratio R_g^* based on the specific surface area produced increased proportionally to the approximate 0.25 power of R_f (the ratio of feed rate to air rate), 0.75 power of Re_t (Reynolds number based on typical nozzle), 1.0 power of R_d (the ratio of feed size to mill diameter) and 0.8 power of Hardgrove grindability, that is, the following non-dimensional equation was obtained; R_G^* = 0.05R_f^Re_t^R_d^Hd
線引き加工したFe-Ni合金線における磁性および弾性の熱処理効果
Get PDF論文(Article)Einige physikahsche Eigenscllaften, d.h. Magnetostriktion, die Magnetisierung und die Biegungselastizitat, waren auf die Eisen-Nickel-Legierungen mit der Kompositionen zwischen 30 und 50% Ni unter den Effekt der varierende thermische Behandlungen, d.h. sowol langsam abgekuhlt nach der zwei stundiger Gluhung bei verschiedenen Temperaturen als nie gegluht, untersucht im Vergleich mit der Veranderungen der mikroskopischen Gefuge. Die Magnetostriktion zeigt in Bezug auf der Nickelgehalt ein Maximum bei etwa 35% Ni die Verhalten davon gleicht die der Magnetostriktionkonstante, λ_111. Die Verhaltnisse der Veranderungen der Magnetostriktion in Bezug auf den Gluhungstemperaturen geben wesentlich dreiartigen Formen, die sich beziehungsweise in den kompositiongebiete bei 30%-,35-40%- und 45-50%-Nickelgehalten befinden. Die Magnetisierung-Komposition Kurve hat ein Maximum bei 45% Nickel und nimmt immer mehr auf beiden Seiten ab, ausschliesslich etwa 30% Ni Gebiet. Die Rate der Erhohung der Magnetisierung ist etwa 5%, ausschliesslich der Proben mit 30% Ni gezeigt 20% Erhohung. Die Biegungselastizitat war gefunden zu einen unveranderlichen Wert 1.7 X 10^ dyne/cm^2 haben, doch der sobald als die Temperatur uber dem Wert trate plotzlich zum Wert nicht hoher als 1.3-1.5 X 10^ dyne/cm^2 verkleinert. Die Magnetostriktion spiegelt sich in der Veranderungen der Gefuge wieder, doch die Magnetisierung und die Biegungselastizitat spiegeln sich in der Umwandiungen von Martensit zu Austenit wieder
微粒子混合液の粘土と沈降特性
Get PDF論文(Article)The methods for the estimation of classification effect and the treatment of dynamical similarity in hindered settling are presented. They are based on the results of the measurements of viscosity and settling characteristics of suspensions, and will be used in developing a better understanding on the settling phenomena and the problem of the scale up in the design of settling apparatus
Diakoptics and Codiakoptics
Get PDF論文(Article)最近G. Kronによって紹介された“ダイアコブテイクス”が複雑な電気回路網の解析に極めて有効であることが認められている[Kdk, Kic, Kmp及びKpi]。更に特殊な条件を持つ回路網では一層簡単化された方法も紹介されている[Wsd及びTse]。それらの方法を要約すれば次のような段階に分けることができる。 (i) 与えられた回路網を数個の部分回路網に分割する。 (ii) 各部分回路網を各個独立に解き等価部分回路網を作る。 (iii) 等価部分回路網を組合せて与えられた回路網の等価回路網を作る。 (iv) 等価回路網の解析によって与えられた回路網の問題を解く。 (i)の段階は切断という操作で行われる。この切断には開放操作と短絡操作の二者を考えることができるが未だ後者については紹介されていない，更に(ii)の段階では等価部分回路網が作られるのであるが，これには端子型と閉路型の二者を考えることができ未だ後者の利用については紹介されていない。(iii)の操作も(i),(ii)の段階に従って導かれる。 (iv)では等価回路網の未知数選たくに点電位と閉路電流の二者を考えることができるが夫夫上の段階に従って便利なるものを使用することが望ましい。 従つて著者はまずKronの方法を単純化し，更に種々の電源の存在する一般回路網に拡張した場合のダイアコプテイクスを紹介し，上述の工夫のもとに“双対ダイアコプテイクス”を新しく提案しようとするものである。その優劣については全く与えられた回路網がいずれの型に属するかによって定まる
わく組の振動を近似する系について
Get PDF論文(Article)In the vibrations of frame work cosisting of many bars we must generally consider three kinds of displacements: torsional displacement, extensional, and flexural. In order to solve simultaneously the equations for these displacements under the boundary conditions and the equations of continuity, we minimize the La-grangian represented by unknown boundary constants, and, consequently, obtain the equations to decide the frequencies and the boundary constants. If the slenderness ratio of each bar is large enough, then it is usually assumed to be infinite in the computations of those equations. And this assumption introduces some modifications of the terms referring to the torsional vibration and extensional one. In this paper, we shall be able to find the physical meaning of the dynamical system corresponding to the vibrations of frame work under those modification
回転する物体よりの熱伝達について
Get PDF論文(Article)The experimental study on heat transmission from rotating bodies, especially on the cylinder and disc, has recently been performed by many researchers. The author has already treated the experiments with rotating bodies. In the present paper comparison is made between authors' and other researchers' results. In the case of natural heat convection, ambient air around the rotating body is disturbed and the coefficient of surface heat transmission increases remarkably, according not only to the temperature difference but also to the peripheral velocity of the rotating body. The experiments are performed as regards three cases, i.e., for the cylinder disc and the rotating bar, and in each case the relation between the Nusselt's number Num and rofating Reynolds's number Rer is shown graphically
円環電極近傍の電界の計算
Get PDF論文(Article)A new expression of electric field near the circular ring electrode is deduced. This method of numerical calculation has many advantages as follows : (1) It is applicable to the calculation of the high frequency field as well as the static field. (2) We can conveniently compare with the both components due to the retarded scalar potential and vector potential, and then find the frequency range of which the later is negligible. (3) The error of results is estimated accurately. (4) This method is easily applied to the case of two electrodes, etc