The strucutre of orthorhombic calcium formate was analysed by the method of Fourier series. Oscillation-rotation photographs were taken with Cu-Kα radiation around the three principal axes and the following unit cell dimensions and space group were obtained, which confirmed the results of the previous work (Nitta, 1927) ; a=10.163A., b=13.381A., c=6.27.1A. (at 18°C) ; space group, D¹⁵_2h—Pcab; Z=8. All the atoms are on the general positions 8 (c) :
± (xyz; 1/2+x, 1/2-y, z; x, 1/2+y, 1/2-z; 1/2-x, y, 1/2+z) .
with the parameters shown in Table I.
The analysis was effectuated by the method of two-dimensional and three-dimensional Patterson syntheses, the latter being evaluated along lines through several points corresponding to peaks in P (xy) .
The structure obtained may be explained as consisting of chains of the type shown in the figure parallel to the c-axis, which are laterally bound through formate ions to form a compact spatial network (Fig.2) . Three types of interionic linkage are found (Fig.3), two of which were already found in sodium formate, analysed by Zachariasen. A remarkable feature is the asymmetrical type of coordination (type II), which might be characteristic to ions of lower symmetry such as this. The calcium ions are surrounded by eight oxygen atoms as shown in Fig.4, one of them being somewhat more apart (Table III) . Pauling's rule concerning the stability of ionic crystals are shown to be strictly hold in its extended form. The shape of the formate, groups were found to be :
C-C=1.25, 1.25, 1.25, 1.24 (±0.03A.) ; OCO=125°, 124° (±4°) .
These results suggest an almost complete resonance between the two forms proposed by Pauling.

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The measurement of stress by means of X-rays has an advantage over any other methods in being more fit to measure the stress of local areas. However, we are often disappointed even by this method in such cases as where the stress has a high gradient in localized regions, such for instance as the stress field near the root of sharp notches. In the present paper a practical method of finding the stress gradient existing in a localized area by applying X-ray diffraction is discussed. It is also found that the Poisson's ratio ν can be determined by this analysis.
It is well known that the breadth of X-ray diffraction line is influenced by the micro-strain included in the material. If the microstrain is replaced by a stress field in a localized area having stress gradient, the profile of diffraction lines emanating from such an area would be likewise broadened and the breadth of the diffraction line would be affected by the stress gradient. On the basis of this consideration, it was intended to analyse the relation between the breadth of diffraction line and the stress gradient, assuming the similarity of the profile of diffraction line to the Gaussian curve.
The results of the analysis can be written as follows;
G=CM√β₂²-β₁²
where G is the stress gradient, C the constant which is decided by the geometry of slit system, M the constant given by the equation
M=Ecotθ/√π{(1+ν)sin²ψ-ν},
where E, ν; elastic constants
θ; Bragg's angle
ψ; angle between the surface normal of specimen and the diffraction plane normal,
and β₂ and β₁ are the integral breadths of diffraction lines of the specimen with and without stress gradient, respectively. In fine, the stress gradient can be determined by measuring the integral breadths before and after applying stress gradient.
The analysis is examined experimentally by measuring the integral breadth of diffraction line obtained from the side surface of a thin plate specimen subjected to bending stress. The results of the experiments show an agreement with the results of the analysis with the maximum scatter of about ±7kg/mm²/mm in stress gradient.

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As one of the X-ray studies of fatigued metals, the author adopted the transmission X-ray diffraction method in this study. Specimens of pure aluminum poly-crystals which were completely annealed were used, and they were fatigued by cyclic tension and compression strainings with a small fatigue test machine which was designed by the author. The test pieces were of the size of about 0.5mm in thickness, 2∼5mm in length and 6mm in width at the smallest section. For most of those fatigue tests, the strain amplitudes were considerably large, which could not be measured, then the fatigue lives were about 10⁴ cycles. The surface of the fatigued specimen was observed at times with an optical microscope, which could be directed and adjusted in three dimensional bearings. It was noticeable that most of the fatigue cracks occurred at grain boundaries.
In process of the fatigue test, the transmission X-ray diffractions of that specimen were exposed on a Laue camera. The X-ray source was of cobalt target, and the electron beam was 30kV and 8mA. A slit of 0.5mm in diameter was used for the X-ray beam. The asterisms of the diffraction patterns were measured statistically, and it was confirmed that the asterisms increased with increase in the number of strain cycles. It seemed that there were correlations between the asterisms and the fatigue damage, though no clear conclusion could be deduced.
The fatigued specimens were further thinned by electrolytically polishing until about 0.1mm in thickness. In the transmission X-ray diffraction of the thinned specimen, it was clarified that the diffracted spots were isolated to fine spots which were elongated; and at the same time, the diffraction rings by the characteristic X-ray, CoK_α, appeared. Since those diffractions were constructed of groups of many fine spots, it seems that the substructure or poly-crystallization developed in the grains of those specimens.
An experiment was also performed of a specimen which was subjected first to tension of over 10% strain. It was then subjected to cyclic straining of small amplitude in tension and compression. Comparative study was made of the X-ray diffraction patterns (a) as the specimen was cyclically strained and (b) as it was statically strained. It was clarified that the diffractions of the statically strained specimen were completely broadened, and these broadened diffractions decreased as the result of cyclic straining. This phenomenon implies that microplasticstrains by the static straining in the grain differ from those by the cyclic straining.

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The change of the lattice spacing of nylon 6 crystal caused by water sorption were studied by x-ray diffraction method. The lattice deformation takes place in the disorded crystals but not in ones with comparatively small disorder such as the crystal whose structure was determined by Bunn. The changes of spacing are confined to the ac plane and are absent in the chain direction, The (200) spacing increases and the (002) decreases after water sorption. The higher the deviation of the spacings from these of the ideal lattice by Bunn, the greater is the deformation when water sorption occurs. Additionaly to the lattice deformation, the width of the x-ray diffraction profiles decreases with water sorption. From these results, it is concluded that water sorption is effective for the relaxation of internal strains in the disordered crystals. This relaxation, however, is insufficient to convert the disorded crystals to the ideal one.

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γ型ナイロン12シートを一軸延伸,ロール延伸,ホヅトプレx,ロール圧延の各種加工処理を施し,結晶配向挙動をX線回折法により検討した.その結果,戦る一概イ申でも140～160.Cの高温で2・4～3倍に延伸したときには,二軸配向性を帯び(200)面がシート面に平行に配向する,すなわち選択的一面配向を起こすが,50～130℃,2.4～4倍の延伸条件ではそのような兆候は示さなかった。この高温延伸試料のX線回折写真では赤道線反射が001(+20i)と200とに分離するが,これは上記(200)面の選択的一面配向と,延伸温度の上昇とともに,001(+20i)反射の面間隔が一定であるのに対し,200反射の面間隔が減少し,シャープになっていくことに起因していると考えた。
さらに,140～160℃の高温でも4.0倍に延伸したときには赤道線反封は分離してみられず,それは面配向した200反射強度が弱くなること,ならびに二つの反射の半価幅が増大することに起因していると推察した。また,各種加工処理による結晶配向様式について若干の考察を加えた。

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Copper-lead alloys are widely used for making sliding bearings. When copper is alloyed with lead, lead acts as a kind of inclusion due to its immiscibility. It is safely presumed, then, that if such inclusions are more finely distributed, the load capacity of bearing materials is increased. In the present study a high-energy type of mechanical alloying method which is recently established for making amorphous alloys was used to give copper-lead alloys an even finer lead distribution. Mechanically ground powders of copper-lead alloy performed for 50hr. in particular shows an evenly distributed fine structure in which the individual lead particles are hardly distinguishable. An X-ray diffraction analysis revealed, however, that the extent of alloying had not reached yet a level that would cause the substitution of copper and lead atoms with each other. Two kind of the sintered materials were made, the one from MG powders and the other from atomized alloyed powders under the same sintering conditions. Comparison between their sintered structures shows that the former structure is finer than the latter one.

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比較的厚い (0.4mm程度) ボリビニルアルコール (PVA) の皮膜に空気共存下または窒素中で⁶⁰Coγ線を照射し皮膜状のまま紫外線および可視吸収スペクトルを観測した。
230および335mμに極大吸収, 280および375mμに吸収の肩, 400-500mμにbroadな弱い吸収を認めたが, このうち335, 375および400-500mμの吸収は吸湿処理または軽度の熱処理により完全に消失するところから, 捕捉ラジカルに基づくものであることを推定した。この捕捉ラジカルは335, 375および400-500mμに吸収をもつような少なくとも3種類のものからなると考えられる。また照射によるこれらの吸収の生成速度を測定したところD₃₃₅>D₃₇₅>D_400-500の順であることを認めた。また, あらかじめ熱処理したのちPVA皮膜を照射し捕捉ラジカルを生成せしめ, その減衰を観測した。その結果, 照射前の皮膜の熱処理温度が低いほど, また減衰温度が高いほど減衰速度は大であることがわかった。PVAの2次転移温度以下で減衰させた場合減衰は平衡になり, ラジカルが残留する。ラジカル残留率は照射前のフィルムの熱処理温度が高く結晶化度の大きいものほど大であった。

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The peak shift and line broadening on 0.06%C steel deformed by tension were measured by means of X-ray diffractometer. These values depended on their diffraction plane.
In this paper, the change in peak shift and line broadening on the diffraction line was discussed with reference to its elastic anisotropy.
The results are as follows.
(1) The change in peak shift on the diffraction line was accounted for by considering that the mean residual stress in the grains in which X-ray diffraction occurred was constant.
(2) Also the change in line broadening was accounted for by considering that the distribution of micro-stresses in each grain or between the grains in which X-ray diffraction occurred was almost the same.
(3) It seems that it was either because the principal stresses in each grain were γ¹≈γ², or because the specimen in this work had texture, that there was but little line broadening due to the difference in the direction of action of the principal stresses.
(4) The mean residual stresses measured from peak shift agreed with that which was obtained by the sin²φ method.

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