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In order to clarify the origin of the discrepancy between theoretical and experimental values of tunneling current through a thin Al2O3 layer, nonuniformity of the thickness of the oxide layer is taken into account in the determination of the theoretical current of an Al–Al2O3–Al thin‐film tunnel emitter. The nonuniformity mentioned above is expressed by a modified Poisson's distribution function with respect to the oxide thickness s=nq, where q is a definite thickness unit and n is an integer. The above‐cited distribution is discontinued by some finite integer κ, by which the distribution function below a thickness s=κq is discarded so that the calculated tunneling current approaches the experimental value. Numerical calculation of the current through the oxide layer with such nonuniformity of thickness is worked out with regard to two samples prepared anodically by using an electrolyte of 3% ammonium tartrate, and the predicted voltage‐current characteristics are actually obtained. Thus, such a scheme c...

Thinking of the mechanism of water decrease in upland, the most important problem is thought to be the prediction of soil moisture content in fields by the indirect element such as meteorological factors. In this case, the soil properties and soil conditions must be cleared up as the preceding conditions first of all. Above all, it is necessary to set up the range of available soil moisture for crop productivity.The initial water content in the soil layer was disccused in detail how to be decided under the natural conditions. The author put next a new definition on the field capacity, that is, “Field capacity is the water content at the time when the amount of drainage water in the soil layer just under the available root zone decrease remarkably curing the night after suppling much water or having much precipitation over the holding capacity of soil layer.” In southern Kyushu, we can see these conditions about 48 hours after precipitation for volcanic ash soil. And then, the water content at 48 hours (W48) become nearly constant value in the indication of the degree of water saturation among the soil layers with different porosities. If we use these values, we can find the initial water content of the soil layer by knowing the amount of porosity. For instance, if we take the soil layer 60cm depth, the amount of porosity ∑Po60, and the degree of water saturation SA60 then the initial water content in the 60cm soil layer (WI60) will be expressed as follows, WI60=SA60×∑Po60=0.80×∑Po60(SA60=0.80……observed value)Next, if we analyze the water consumption with the water balance method, we must divide the moisture flux into the upward flow and the downward flow. As to the evapotranspiration, the downward moisture flow must be excepted from the calculation. What is the critical value dividing the flow into the upward or the downward? The author considered of this problem from the standpoint of the environmental evaporation capacity, which is calculated as the latent heat flux in the heat balance equation. Judging by the comparison, the critical value is thought to be the value of pF1.6, and that corresponds to the 48 hours water content (≅field capacity) for volcanic ash sandy loam in southern Kyushu.We examined the relationships among the estimated amount of evapotranspiration from the heat balance method (lEo/l), those from the net radiation (S/l), tne' observed evaporation with 20cm pan evaporimeter (Ew) and the observed evapotranspiration from the soil layer of 0-50cm by the water balance method (pET). As the results of these comparisons, the relationships, pET=lEo/l=EW……(W≥W.c.)were found out in our experimental fields throughout the duration from July to November.The water content in the soil layer of 50cm (W50) is obtained from, W50=SA×∑Po50-WW50-pET·t……(W≥W.c.)W50=(SA×∑Po50-WW50)·exp(-W/W.c.×pET·t)…(W

Based on the logistic theory on the plant growth, the analysis was made on the mechanism of soil moisture on the growth of upland rice plant. Seeds were sown on June 10, 1968 in the plastic Wagner pots (1/2000 a) and after 24 days the soil moisture was regulated to about 10 different levels. Treatments were continued till the harvest time in glass house, of which air temperature were exceedingly high (about 2-8°C higher than those of outdoor) throughout growing season. Average weight of dry matter of upland rice plant on the 37th, 70th and 119th day from sowing were used for the present analysis.The results were summarized as follows;(1) The effect of soil moisture on the plant growth were the optimum factor in the logistic theory (Fig. 3 and 4).(2) According to the logistic theory, the effect of available soil moisture saticefied the following optimum factor equation, 1/w=Af+A′/f+Bwhere, w is the total dry weight per plant at a certain time (t) and f is the amount of a factor supplied (soil moisture), A, A′ and B are the functions of time as defined by Eq. (2).In this experiment, the fitness of the equation with the experimental results was satisfactory (Fig. 5).(3) Soil moisture must be expressed by the available moisture (% in dry base) which was subtracted by the moisture of the initial wilting point for 37 and 70th day, and of the permanent wilting point for 119th.(4) The optimum soil moisture changed from lower to higher with plant growth.(5) Soil moisture affected mainly the growth of top parts of plant throughout whole growing season, and in the leaf area at middle stage.

Aromatic trichloromethyl compounds such as 4, 5-bis(trichloromethyl)imidazole, 1-methyl-4(trichloromethyl)imidazole-5-carboxylic acid, 1-methyl-4- (trichloromethyl)imidazole, ev-(trichloromethyl)-pyridine and benzotrichloride reacted with o-phenylenediamine or 3, 3 -diaminobenzidine, giving corresponding benzimidazole derivatives.