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The defect-related donor-acceptor pair emissions in photoluminescence spectra of CuInS2 crystals grown by the traveling heater method have been investigated to characterize the defects in the crystals. The energy levels of donors have been deduced to be 36 and 63–69 meV. Acceptors have been estimated to lie much deeper with energy levels at 113, 150, 180 and 220 meV. The origin of the donor and acceptor levels is discussed.

Infrared absorption at longitudinal optical (LO) frequency was measured in amorphous aluminum oxide, amorphous magnesium oxide and their mixtures. It was found that the LO mode of a mixture of these oxides has a single peak, and its position lies between those of the constituents if two oxides are mixed on the order of angstroms. The LO mode of amorphous MgAl2O4 is also reported.

9-(2, 6, 6-Trimethyl-1-cyclohexen-1-yl)-3, 7-dimethyl-2, 4, 7-nonatrien-1, 6-diol, an important intermediate for synthesis of vitamin A acetate, has been synthesized directly by using a polyfunctional lithium reagent prepared by the action of lithium-arenes to the corresponding chloride.

Regio- and stereoselective oxidation of ene-type chlorinated olefins has been achieved by using potassium 2-propanenitronate as an oxidant and tetrakis(triphenylphosphine)palladium as a catalyst.

Selective synthesis of pseudoionone was achieved by the acetylenic oxy-Cope rearrangement of 4-isopropenyl-3,7-dimethyl-6-octen-1-yn-3-ol ( 3 ) in N-methyl-2-pyrrolidone solvent containing a trace of hydrochloric acid, hydrobromic acid, iodine, ammonium bromide and ammonium chloride catalysts.

Tensile test pieces of aluminium bi-crystal were obtained by the strain annealing method from commercial aluminium plate. Orthogonal grids of 20lines/mm were printed on the surfaces of the specimens. The plastic deformation of these specimens were measured by the usual moire technique. The amount of deformation obtained experimentally almost agrees with that calculated on the basis of slip of crystal plane, but it becomes small near the grain boundary. That is, the grain boundaries tend to restrict deformation of crystals. The distribution of elongation in the neighborhood of grain boundaries is similar to the result obtained by Urie and Wain4). The effect of grain bondaries reaches to 2∼5mm from grain boundary. It seems that the extent of such region is related to the Schmidt's factors of bi-crystals and their slip direction.Next, to examine the rotation of crystal lattice induced by plastic deformation, Laue photographs were taken. For this purpose, about ten slits of 4cm in length and 0.45mm in diameter were set in a row. This slits system makes it possible to take Laue patterns around the grain boundary on a X-ray film. It was observed that the amount of rotation of crystal lattice and the direction of its rotation axis are abnormal in the neighborhood of grain boundary.

Stereocontrolled convergent synthesis of vitamin A was achieved by the double elimination method employing the C10 sulfone and the C10 aldehydes as starting materials. Thus the all-trans and 13-cis isomers were obtained with the stereochemical purity of 95% and 90%, respectively.

The ethynylation of ketone (2) in liquid ammonia at −33°C with stoichiometric sodium acetylide afforded the corresponding alcohol (3 and 4). Similar treatment of 1 resulted in only a little isomerization to 2. Favorskii ethynylation under pressure at 0°C yielded a mixture of 1, 2, 3 and 4 without any detectable 5, whichever ketone 1 or 2 being used.

Oxy-Cope rearrangement of diastereomeric l,5-hexadien-3-ols, new key intermediates for terpenoids pio-duction in industrial scale, were investigated in neat systems and solvent assisted systems. Various solvents affecting the selectivity of [3,3]-shift were classified by means of NMR studies on hydroxyl proton exchange time.

The results of studies with respect to hydrogen embrittlement phenomenan have been reported by many workers and many hypotheses of that mechanism are advanced, but it seems that any unified opinion is not published.Then, in the study of that mechanism, it is significant to discuss about hydrogen-occluded steels under various stresses.From this point of view, this paper deals with the hydrogen embrittlment of commercial steels which are subjected to the constant load rupture test.Hydrogen was charged into steels cathodically under given constant loads (bath; 5% sulphric acid in poison phosphorus, charging temperature; R.T., current density; 0.08-0.09 amp/cm2, anode; platinum coil).The steels examined were carbon steels, chromium steels, stainless steels, 60 kg/mm2 class and 80 kg/mm2 class high tension steels, all commercial.This work discusses, using base material specimens and weld joint specimens of each steel, their susceptibility to hydrogen embrittlement.The results are summarized as follows:(1) The gradient of hydrogen embrittlement lines (relations between given stress and fracture time) for 80kg/mm2 class high tension steels are very steep and the stress range in which a hydrogen-delayed fracture occurs is very wide: 60 kg/mm2 class, carbon steels and chromium steel show in this order gentler slope and narrower stress range in which a delayed fracture occurs. Therefore, 80 kg/mm2 class high tension steels suffered most embrittlement and carbon steel did less embrittlemt. Stainless steel did not fracture by hydrogen.(2) High tension steel being affected by hydrogen, in the construction of high tension steels close attention must be paid to the problem of hydrogen embrittlement.(3) The susceptibility to hydrogen embrittlement of weld joint specimens was very different from that of each steel. High tension steel onffered most embrittlement which was more remarkable than in base material specimens. The fractured part mostly falls on bond and H.A.Z., for the welded part is affected easily by hydrogen.(4) When hydrogen-occluded steels were placed in a certain stress field, hydrogen cracks initiate at the defect and inclusion which exist already in steels and propargate. Propagation of hydrogen cracks is affected by the structure of matrix and the distribution of the lamination, but it needs more detailed microscopic analysis.

Fatigue crack propagation in epoxy resins containing 0 wt% to 45wt% plasticizer was examined. In this experiment, double-cantilever type specimens were used. The stress intensity factor was adopted to express the stress near the crack tip. When specimen was cyclically loaded, not only the range of stress intensity factor ΔK but also the maximum stress intensity factor Kmax or the mean stress intensity factor Kmean were taken into consideration. Under the assumption of dl/dN=A(Kmax)α1(ΔK)α2 or dl/dN=B(Kmean)β1(ΔK)β2(dl/dN means the fatigue crack propagation rate) as the fatigue crack propagation law, dl/dN was measured for several combinations of ΔK and Kmax or Kmean and the values of constants A, α1, α2, B, β1 and β2 were evaluated from the values of log(ΔK) and log(Kmax) or log(Kmean) by means of least squares analysis.As the results, it was found that as the percentage of plasticizer increases, A and B increase by two orders, α1 and β1 decrease by 40%, and α2 and β2 decrease slightly. For the specimen without any plasticizer, both α1 and α2 are equal to about 5, and for the specimen with 40 wt% of plasticizer, both β1 and β2 are equal to about 4. It is interesting that the exponent of ΔK remains constant in spite of the decrease in exponent of Kmax or Kmean. The mechanical properties vary widely from the brittle fracture type to the ductile fracture type as the percentage of plasticizer increases, and it seems that the above interesting results about the fatigue crack propagation behavior in epoxy resins containing plasticizer are principally attributed to the difference in their mechanical properties.