Fundamental formulations are given for the potential distribution of acylindrical and a hollow cylindrical objects with a rotational symmetry.Thisprocedure is performed by solving Laplace's equation in polar coordinates usingthe method of separation of variables.By limiting the inner radius of ahollow cylinder to zero, it can be proved that all the formulations for the hollowcylinder become to those for the cylinder.A few examples of numericalanalysis are quantitatively done for the boundary conditions with constantpotential value on the cylindrical and hollow cylindrical surface.The obtaineddata with respect to convergence of a series sum and resultant potentialdistribution are presented for the different boundary conditions.

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This study was carried out for the purpose of investigating the corrosionbehavior and mechanism on a separator for a molten carbonate fuel cell underboth the electrolyte and cathode side environment. A SUS310S austenitic stainlesssteel was used as the separator material. Corrosion proceeded via threesteps; a formation step of corrosion product in which rapid corrosion take placesuntil a stable corrosion product is formed after the beginning of corrosion;secondly, a protection step against corrosion until breakaway occurs after theformation step of the stable corrosion product;finally, an advance step of corrosionafter breakaway. From the standpoint of the behavior of the elementsin the separator, Fe, Cr and Ni were formed richly in the region of the corrosionproduct, in the region of corrosion protection, and at the Cr-depleted zone respectively. With respect to the corrosion mechanism, direct reaction with electrolyteand elements of the separator at the cathode side was the main corrosionmechanism, and the final corrosion product was LiFeO₂. The corrosion rate ofthe separator at the cathode side was rapid at the initial stage of corrosion.However, the corrosion rate was decreased due to the resistant effect of chromiumoxide.

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The effect of crystallization on corrosion properties of amorphous Iron basealloys was investigated by the measurement of potentiostatic polarization curves in H₂SO₄+NaCl solution.The crystallization process of the amorpous wasstudied by X-ray diffraction, electrical resistivity and passive current density.The passive current density exponentialy increased with increasing the isothermalannealing temperature.From the change of the passive current density, the activationenergy of the crystallization process was estimated to be 49kcal·mol^-1for amorphous Fe₇₂Cr₈P₁₃C₇, and to be 60.8kcal·mol^-1 for amorphous Fe₆₄Cr₁₆P₁₃C₇.These activation energies were nearly the same values as were obtaindfrom the change of electrical resistivity.

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In the previous paper, we proposed the method to recognize the existence ofthe rock pile by use of the image and laser slit light. In this study, we proposethe method to estimate the amount of the rock pile by use of the image and forcesensors. In order to estimate the amount of the rock pile, three dimensionalmeasurement of the rock pile was carried out. Furthermore, in order to detectthe contour of the rock pile, the force sensors were used. In this experiment, two strain gauges were used as force sensors.
Several kinds of rock piles were made and the experiments to estimate theamount of the rock pile were conducted. By comparing the estimated valuesand the actual ones, it was confirmed that the method proposed here works well. Furthermore, the shoveling task was planned based on the three dimensionalshape of the rock pile.

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A predicting method was proposed of high-temperature deformation behaviorwith Ostwald ripening of Si precipitates for over-aging stage in Al-1.03mass% Si alloy based on the Void-hardening mechanism.The evaluation wascarried out of the time dependence of strain, threshold stress, dispersion parametersof Si precipitates and stress-strain curves. The effects of temperatureranging from 523K to 723K and stress ranging from 6.7MPa to 90MPa ondeformation behaviors were examined by this predicting method. The influenceof Ostwald ripening of Si precipitates on high-temperature deformation behaviourswas revealed in Al-Si precipitation-hardening alloy. The results were ingood agreement with experimental ones.

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In this paper, in order to establish a new engineering field based on thecomprehensive knowledge of humanities and science, the food crisis of humanbeings in the near future has been taken into notice and discussed from a pointof materials culturology.As a result, it has been pointed out the food crisisto be one of short term & serious problems.And, to overcome the food crisisin the near future, new concept of artificial photosynthesis system supportingthe food poroblem of human beings has been conceptually presented.And thefeasibility has been fundamentally discussed from points of materials engineeringand materials culturology.
The following results has been obtained.
1) The photosynthesis mechanism of green plant was discussed from a pointof materials engineering, and five conditions necessary to realize the photosynthesisare fandamentally elucidated.
2) The five conditions of 1) were shown to be satisfied by intoroducing the concept or Φ/1-Φtype of pn-conjunction particle.
3) The optimum combination of photosynthesis catalysis was pointed to beAIN, SrTiO₃, Sr_0.75 Ag_0.25 TiO₃, GaSe, GaTe, SnS.And each photosynthesis catalysiswas quantitavely designed into Φ/1-Φtype of pn-conjunction particle.
4) New two concepts of photosynthesis ceramics element and photosynthesissystem, necessary to photosynthesize glucide from CO₂, H₂O and the sunlight, were presented.
5) The area of the leaflike plane of photosynthesis system, necessary tosynthesize the per capita daily consumption of glucide 250g, was pointed out tobe 1.2m².

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In this paper, the “White Box” ing the technology information in particulate processes was taken notice from the standpoint of overcoming the information gap between “user” and “maker”.
To overcome the information gap between “user” and “maker” in particulateprocesses, two problems have to be soluted.One is “White Box” ing of particulatebehaviors such as powder flow, powder compact, powder storage, powder mixing.
And the other is that of technology information through “catalogue” between “user” and “maker”.
From the standpoint above, X-ray radiograph measurement method wassuggested to play basic and important role to overcome the particulate behaviorgap.
The latter was discussed by searching the actual catalogues in particulateprocess industries in Japan.And, as the result, a new concept of “catalogue” getting understanding between “user” and “maker” in particulate process industries.

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In-situ dynamic observations of surface phenomena using scanning tunnelingmicroscopy (STM) are performed.One of the example is as for the homoepitaxyand reconstructions on the heating Si (111) substrate.The growths ofthe 7×7 reconstruction and the 5×2 reconstruction due to gold deposition areobserved in the atomic scale.
The other observation is for the surface modification in the atomic scale onthe molybdenum-disulfide (MoS₂). The individual atom on the surface is subtractedby the atomic manipulation using field evaporation phenomenon.

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