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We have investigated the oil penetration speed into paper which are vertically directed to paper surface, by means of the penetration volumeter.According to Lucas∼Washburn or Kozeny-Carman equation, the penetration volume V is followed to the next equationV=K√T cos θ/η·√tt : time K : constantT : Surface tensionη : Coefficient of Viscossityθ : Contact angleof used oilResult of ObservationV∼√t plots are on straight lines. In almost cases, these lines are separated in two parts evidently.For this cause, anisotropy of paper in vertical direction to the paper surface are thought.We may conclude that, the penetration speed in internal layer are different to the speed in external layer.On the machine made paper, it seems that difference in distance from surface to central layer exist between wire side and felt side.Though we have not determined manifestly these differences in distance. In penetration speed no difference was observed.Beating effects on penetration speed were also observed. As beating proceeds, penetration speed decreases. This is easily prefigured, more interesting matter, at certain point in the beating procedure isotropic property of paper regards oil penetration have been obesrved, but we could not understand its reason.Calendering effects on penetration speed were discussed. As a matter of course, the penetration speed had been greatly decreased by calendering, and passing through time in the case of not fully beated paper, the penetration speed recovered, but in the fully beated paper, their recovering effects were not observed and the penetration speed had become almost homogeneous.

The paper by Bachmat and Bear [1964] is the most recent of many that have come to my attention in which emphasis is given entirely to the analytical form and implications of what is assumed to be the governing transport equation for hydrodynamic dispersion in porous-medium systems. But this partial differential equation tends to be nonlinear and of high order, with high-rank tensorial as well as vectorial terms, and many ramifications must be introduced to treat the most general cases of unsteady and nonuniform flow of inhomogeneous fluids in inhomogeneous (and perhaps anisotropic, and perhaps nonlinearly elastic) porous solids, for example in cases where there may be two or more immiscible interstitial fluids, so that saturation becomes an added dependent variable and so that fluid-solid interfacial interactions assume importance. Additionally, for completeness one may wish to consider the possibility of chemical reactions and of effects involving solution of the solid matrix and/or precipitation from the fluid saturants. To be even more general one may wish to take explicit note of complicated phase changes due to temperature and/or pressure variation.

By determining up to 16 GHz the effective dielectric constant for microstrip lines with various strip widths, it has been found that anisotropy in alumina substrates considerably affects the wavelength and is responsible for most of the discrepancy between theory and experiments

If Dr Mason does not venture an explanation of the phenomena of the different morphological forms of ice formed at different temperatures, I will take the risk of putting forward one which, to be honest, I only thought about this morning. If it is right, and I think there should be fairly simple means of testing it, it would apply in general to all crystallizations from the vapour which occur in conditions not far removed from equilibrium, that is where we do not need to consider the different concentration of vapour near the crystals, for it has been long known especially since the work of Papapetrou (1935) that rapid crystallization involving impoverishment of vapour in the neighbourhood of the growing crystals favours the growth of rapidly extending dendrites reaching out into the denser vapour regions. Now the hypothesis I want to put forward depends on some work of Hale (1957) reported at the International Crystallographic Congress at Montreal in 1957 on the crystallization of a very different substance, namely, quartz in hydrothermal containers. Crystals of quartz grown from a small seed show on sectioning diagonal lines marking out the regions that have crystallized on the c or (0001) face from those that have grown on the prismatic faces (101̅0) (figure 64 A ). This, of course, has been known for a long time, but what was not so well known was that careful analysis showed that the very small degree of impurity present—and the major impurity in the case of quartz-growing is nearly always aluminium—had a very different concentration in the different parts of the crystals being practically absent in the c and present to its full amount in the a . In other words we were dealing not strictly with a homogeneous material, but with two different materials crystallizing together—what might be called c quartz and a quartz. If this is correct it is not sufficient in general to specify crystalline material by its formula, but rather to say this is material crystallized on such and such a face, because strictly every face will have a slightly different composition. This would be true even in the absence of material impurities, because there is one impurity that cannot be avoided and that is simply lattice vacancies. Now the condition of growth of a crystal which is very anisotropic, that is growing in long needles or thin plates, will be quite different from that of one growing approximately equally in different directions, as quartz does. The observations on such growth show that after an initial period when the crystal reaches approximately its full width, subsequent growth is confined to the major direction, and may be many times more than that in the other. The kind of conditions are shown in figures 64 B and C .

The requirement that the work done to deform a virgin element be non-negative implies restrictions on the relaxation moduli of an anisotropic linear viscoelastic solid. The present paper is devoted to a study of these restrictions. It is shown that if the work is non-negative, then the tensor of relaxation moduli is fully symmetric at time zero and it can be represented by certain Fourier—Stieltjes integrals. Conversely, if the relaxation moduli are representable by the same Fourier—Stieltjes integrals, then the work done is non-negative. It is also shown, by means of a counter example, that the requirement of non-negative work is not sufficient to ensure the full symmetry of the tensor of relaxation moduli for all times.

The recent paper by Bachmat and Bear [1964] summarizes very nicely the results of recent investigations of the problems of dispersion in porous mediums. One of the fundamental concepts of the theory is that the dispersion tensor Dik may be expressed as the double contraction of a fourth-order geometrical dispersivity tensor αiklm and a second-order velocity tensor ulum/u. The theory as it now stands is applicable only to homogeneous isotropic mediums, i.e., ones in which αiklm is isotropic. At present there appears to be no extension of these results to anisotropic mediums.

A Fabry-Perot resonator formed by parabolic cylindrical reflecting mirrors and filled with anisotropic medium is analyzed theoretically. For the resonance of the extraordinary wave in such a resonator, optimum shapes of the reflecting mirrors exist, which are derived from the boundary conditions on each mirror.

A special handsheet-making apparatus, in which the velocity component of the pulp suspension is parallel to the forming wire, was constructed. The tensile properties of the fiber oriented handsheets were compared with those of the TAPPI standard handsheets. Holocellulose and sulfate pulp of softwood were also used for making handsheets. The fiber angle distribution φ (θ) was expressed in Fourier series : φ (θ) =1+α1cos 2θ+α2 cos 4θ+α3 cos 6θ+…The coefficientsα1 andα2 were used for the characteristic values of the fiber orientation. It was found that the fiber orientation of the sheet prepared from holocellulose was higher than that of sulfate pulp.Astress-strain curve at a constant rate of elongation was normalized in such a way that the stress at 1mm elongation (2% strain) was one unit. Such a normalized curve was called a master curve. The master curves of the sheets prepared from the same pulp are almost the same irrespective of the degree of fiber orientation. The master curves in the machine and cross directions are also the same one.Namely, it may be possible to express the stress-strain curve by the shape of master curve, the stress at the constant strain and the ultimate strain. The value of f/w is the stress (at 2% strain) divided by the weight of test strip. The value of (f/w) r is the ratio of f/w of machine direction to that of cross direction, and it represents the degree of anisotropy of the sheet. The (f/w) r of the sheet treated with resins (melamine resine and polyvinyl acetate resin) is lower than that of the untreated sheet. The ultimate strain has no relation to the fiber orientation.

The crystallographic characterization of judaicin have revealed that its crystals are of the monoclinic system, normal class with eight faces and sometimes twinned. The optical characterization have shown that its crystals are anisotropic, biaxial, positive with small optic axial angle, 2V = 10°; its refractive indices were found to be ny = 1.609, nB = 1.547 and na = 1.546. The birefringence = 0.063; the extinction angle Z/C = – 3°. Judaicin has been characterized chromatographically and its Rf values were determined using paper and thin layer chromatography. A colour test has been devised by which it was possible to detect judaicin in a drop of 1 : 1000 solution. Die kristallographische Analyse von Judaicin hat ergeben, das es sich um monokline, anisotrope Kristalle mit den Brechungsindices ny = 1,609, nB = 1,547 und nrx = 1,546 handelte. Judaicin wurde papier– und dunnschichtchromatographisch charakterisiert. Ein Farbtest ergab, das es moglich ist, Judaicin in einer Verdunnung 1 : 1000 nachzuweisen.

In a recent paper Raman and Krishnan have shown how the phenomenon of birefringence exhibited by liquids in a magnetic field can be utilised to determine the degree of magnetic anisotropy of the molecules concerned. Since magnetic double refraction is an effect arising from the molecules being both magnetically and optically anisotropic, and the optical anisotropy is known from studies on light scattering, the magnetic anisotropy can be evaluated from the known value of the Cotton-Mouton constant. In this way, they showed that the benzene molecule has a high degree of magnetic anisotropy, the susceptibility in a direction perpendicular to the benzene ring being about twice as great as that in any direction parallel to the ring. In another papers they showed how this magnetic anisotropy may reasonably be explained in terms of the special structure of the benzene molecule. Considerations of the same kind suggest that the higher members of the aromatic series ( e. g. , naphthalene and anthracene) should exhibit an even more striking degree of anisotropy. Some calculations, as yet unpublished, by Krishnan indicate that the naphthalene molecule should have, in directions perpendicular to the ring, a susceptibility about four times as large as in directions parallel to the ring. It is known that diamagnetism of crystal is in general anisotropic. In a recent paper Raman and Krishnan have discussed the case of nitrates and carbonates and shown how the anisotropy of the crystals is in each case connected with the structure of the individual ions. If, as stated above, the naphthalene molecule possesses a large magnetic anisotropy in the liquid state, it is reasonable to expect that naphthalene crystals in the solid state should also exhibit a very pronounced magnetic anisotropy. In fact, Bragg and Oxley have made some qualitative observations on the magnetic behaviour of naphthalene crystals which support this inference, but no quantitative results are available. The present work was undertaken with a view to obtain some measurements of the susceptibility of the crystals in different directions and with the hope that such data would be of assistance in determining the orientation of the molecules in the crystal lattice.

Recent investigations on the diffraction of X-rays by liquids throw considerable light on their molecular structure. One conspicuous result that emerges out of these investigations is that when the molecules are asymmetric in shape, as in general they are, their average distribution around any given molecule in the liquid is far from being spherically symmetrical with respect to it. When the medium is under the influence of an electric field, the well-known Lorentz polarisation field acting on any given molecule, arising from the polarisation of the surrounding ones, will then naturally vary width the orientation of the exciting field with respect to the molecule. Independent evidence for such an “anisotropy” of the polarisation field is forthcoming when we correlate the measurements on electric double-refraction and on light-scattering in the liquid state with the corresponding values for the same substance in the state of vapour, The general mathematical theory of refraction by dense media takes into account this anisotropy of the polarisation field, has been developed in a recent paper. It is proposed in the present communication to discuss the theory outlined in that paper in its relation to actual experimental results, confining ourselves mainly to one typical case, viz., benzene, for which accurate measurements are available for the various physical quantities appearing in the expressions.