The heat exchanger, especially shell & tube type, is basical appratus for heat transfer equipments in various industrial and district fields. The metal tubes, such as cupper, steel and so on, are usually employed in shell and tube heat exchanger. On the other hand, PFA tube using in this exchanger have many advantages that are stable against chemical solution, prevent to get rust, etc.. However, heat exchange efficiency is low value, since PFA has lower thermal conductivity than metals' one. If the conductivity of PFA tube is improved by mixing high conductivity powder in it for example, the effective thermal conductivity of tube may be more larger value and its means bring about large benefit on energy resources.
From this standpoint, we developed the apparatus to measure the thermal conductivity of the thin tube. The data on pure PFA tubes having different 3 sizes diameter are obtained and compared with the data taking from the same dia. tube mixed carbon powder. It is clear that the conductivity of mixed tube have grater value about 1.6 times than pure PFA tubes. Therefore, these mixed tube may be take many improvement to heat exchange coefficient.

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It is generally known in the brass mill industry in Japan that CDA Copper Alloy C64740 (Cu-Sn-Ni-Si-Zn system copper alloy) is used for copper-leadframe material which satisfies high quality requirements corresponding with miniaturization of semiconductor devices.
Many studies on precipitation of Cu-Ni-Si system copper alloy have been performed in the past seventy years since M. G. Corson invented it in 1927. However, the precipitation of Cu-Sn-Ni-Si-Zn system copper alloy containing a small content of Ni and, in particular, Si has not been studied, sufficiently.
C64740 which is commercially produced shows a very fine structure, and small precipitates having maximum length of 1μm under in the rolled strip, and keeps the precipitates with a good recrystallization even though it is annealed at high temperatures from 723 K to 873 K for 3.6ks, which indicate a possibility to give a favorable fabricating and plating property to leadframes.
The precipitates in the alloy aged after solution treatment and cold rolling are finer than those in the alloy aged without cold rolling after solution treatment. Meanwhile, the grains grow rapidly in the solution treatment at 973 K. Therefore, it might be preferable in the production to get the finer precipitates while the grain refining is maintained.

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It is a important analysis to evaluate correctly the size of fine or ultrafine particles for raw materials or products in many kinds of industries. There are many different principles to measure the particle size. The laser diffraction and scattering method is the most popular one, but it is first necessary to confirm the particle size by a microscope.
In this study, size distributions of Sr-ferrite particles were measured by the microscopic method and the laser diffraction method. The Sr-ferrite particles used as the sample were ground in the dry, the wet and dry grinding with methanol as grinding aid by a ball mill. The particle size distributions which were measured by the two methods were compared.
As a result, the sizes measured by the laser diffraction method were larger than the feret diameters measured by the microscopic method.

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CoxPt₁₀₀-x (33 ≤ x ≤ 97) thin films were fabricated by RF sputtering method with various sputtering Ar gas pressure P_Ar and film thickness t and applied to hard magnetic tips for Magnetic Force Microscopy (MFM). The coercivity Hc of Co-Pt films, which were fabricated under high P_Ar, increased in the Co concentration range beyond 60at. % Co. The maximum value of μ₀Hc, 0.27T was obtained for the Co₇₉Pt₂₁ films with P_Ar=10.7Pa and t=40nm. X-ray diffraction analysis revealed that hcp phase exists in the films with high coercivity. The anisotropy field μ₀Ha of the hcp phase was estimated about 1.0T by singular point detection technique. The high coercivity of the films is attributed to domain wall pinning from the minor loop behavior. The MFM tips with Co₇₉Pt₂₁ films on Si cantilevers gave finer contrast in MFM images than commercial CoCr MFM tips for magnetic recording media.

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SiO₂-TiO₂ porous glasses were prepared from SiO₂-TiO₂-B₂O₃-Na₂O glasses by means of the phase-separation method. The performance as humidity-sensor elements were examined by the electric resistivity according to the relative humidity change. The porous glass containing 25 mass% of TiO₂ showed good performance in the machine processing and the sensibility of humidity.
The preparation at low phase-separation temperature (773K) gave the porous glasses with small diameter pores and large specific surface area. The electric resistivity extensively of them changed from 30 Ωm to 15 × 10⁶ Ωm with relative humidity change. Leaching the porous glass element in NaOHaq. shortened the response time without changing the electric resistivity.

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To define the comminution mechanism and achieve a high recovery of fine particles, dry tower mill KD-1 and KD-2 have been developed and modified into KD-3. In this study, grinding tests were carried out on limestone to clarify the comminution mechanism in the KD-3.
A particular attention was paid to important factors such as size of the grinding media (steel balls of ∅10mm, ∅13mm, ∅16mm, ∅20mm), the speed of the stirring screw [from 1.08s^-1 (65 rpm) to 1.58s^-1 (95 rpm)] and the role of nets in the classifying column. The study has revealed an optimum efficiency for steel balls of ∅20mm size and stirring screw rotating at 1.58s^-1 (95 rpm). Besides, the maximum particle diameters of products were indicated by the corrected curve which is estimated by the assumption of Stoke's law. The relationship between maximum and 50% particle diameters was proportionally and by using the columns provided with nets, the overflow products were classified by high classifying efficiency.

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