87才男子および47才男子の2例の顔面の基底細胞上皮腫に対して, パパニコロー染色による細胞診を施行した。両症例ともに細胞診陽性で, しかもその細胞診所見は基底細胞上皮腫に特徴的であり, HE標本とも一致する所見であつた。すなわち, ライトグリーンに一様に染色される小型の腫瘍細胞が密に配列し, クロマチンパターンは粗大顆粒状で, 細胞像は比較的均一であつた。また, 両症例に対して, 擦過, 穿刺吸引, 捺印細胞診の3つの方法を施行した。その中でも, 穿刺吸引細胞診は, 手技が簡便であること, 陽性率が高いこと, 皮下腫瘍を含めて適用範囲が広いことなどから, 他の2方法に比べてきわめて有用であると考えた。

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It is known that it is difficult to bond dissimilar metals such as aluminum and copper or aluminum and iron using diffusion bonding, because an intermetallic compound is easily produced at the bond interface and bonding strength becomes low. However it is possible to bond the dissimilar metals using the vacuum roll bonding which performs hot rolling in a vacuum. In this study, we investigated the effect of bonding temperature and reduction of aluminum plate thickness on bonding strength of Al/Cu clad materials when aluminum-clad copper (Al/Cu clad) materials were produced at 3 Pa in vacuum degree by the vacuum roll bondings. Bond tensile strength of Al/Cu clad materials increased as the reduction was increased. Their fracture types were classified according to the fracture pass, that is, in the base metal of the aluminum, at the bond interface of Al/Cu clad material or in the base metal and/or at the bond interface. Furthermore, the bond interfaces of Al/Cu clad materials were observed using a transmission electron microscope and an electron dispersive spectroscopy. As a result, it was clarified that Al/Cu clad materials are soundly produced using the vacuum roll bonding when thickness of diffusion layer is less than 60 nm even if intermetallic compounds were developed.

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The fusion weldings of the spheroidal graphite cast irons are very difficult because cracks are initiated in the weld metal and the heat affected zone. However, since the diffusion bondings are performed on the solid state of the materials, the sound bondings would be obtained between the cast irons and also between the cast iron and the mild steel with Ni foil as an insert metal. When the bonding surface has a conical configuration, Ni plating to the surface might be useful instead of the Ni foil as an insert metal. In this study, the diffusion bondings were applied to the bondings between the cast iron and the machine-structural carbon steel. It was made clear that the bondability of the materials with Ni plating method was superior to that with Ni foil.

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大入熱溶接における熱影響部の切欠靭性改善のためにチタン(Ti)の添加が有効である。本研究は、入熱量が及ぼすTiによる窒素(N)の固定効果によるフェライト結晶粒中の固溶Nの低減効果について、X線小角散乱法を用いた迅速定量分析法を確立し、定量的に解釈することを目的とする。本実験はSPring-8の産業利用IビームラインBL19B2を使用して極小角散乱測定を実施した。再現熱サイクル試験における入熱量の増加に伴い、未溶解窒化物(TiN)、再析出TiNの数密度および体積率の変化を意味する散乱プロファイルの強度変化を捉えることに成功した。

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Influences of chemical compositions of base metal, temperature difference ΔT between liquidus and solidus, and arc time on the susceptibility of liquation cracking were studied using the Varestraint test on 6082 aluminum alloy which was GTA spot welded. A commercial 6082 alloy and seven kinds of experimental 6082 alloy whose magnesium, silicon and manganese contents were changed were used. The susceptibility of liquation cracking was evaluated from the maximum crack length observed in heat affected zone after the Varestraint test. Liquation cracking was observed along grain boudaries on which low melting point compounds (mainly Mg₂Si) were melted. The maximum crack length increased with arc time and ΔT. The addition of Si and Mg which increased ΔT promoted the liquation cracking, whereas the Mn addition suppressed the cracking by grain refining.

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We investigated the influences of bonding parameters on joint strengths of diffusion bonds between swaged tungsten and titanium (case A), and between rolled tungsten and titanium (case B). In case of A, joints bonded at temperatures of 1073 K and 1473 K for a bonding time of 1.8 ks showed the tensile strengths of 120 MPa. The joint strength obtained at a bonding temperature of 1073 K increased with increase of bonding times, and for a bonding time of 30 ks reached about 240 MPa, which was 88% of the tensile strength of the tungsten base metal. In the case of B, joint strength obtained at a bonding temperature of 1173 K was 16 MPa, when fracture occurred along grain boundaries. In the both case, the voids were formed in titanium base metal away from the W/Ti interface. It is therefore seemed that the existence of voids give no effect on the joint strength.

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YAG laser welding was performed on A5052-O and -H34 sheets (thickness: 2 mm) in several different welding speeds with the constant out put power of 2000 W. The authors investigated the distribution of Vickers hardness in both weld metal and heat-affected zone (HAZ), and the influence of heat treatment on Vickers hardness in the weld metal from the view point of micro segregation of magnesium in dendrites.
In the HAZ of A5052-H34, the soft region where the hardness is almost the same as A5052-O base metal is developed just near the fusion boundary. Then the hardness increases with the increase in the distance from the fusion boundary toward the base metal and finally reaches the value equal to A5052-H34 base metal. This is caused by the change of the maximum temperatures in the HAZ due to welding.
In the weld metal of both A5052-O and -H34 the hardness increases and dendrite arm spacing decreases as welding speed increases. When the heat treatment is performed on the weld metal at 500°C for 24 h, the hardness decreases down to the value of A5052-O base metal. According to the simulation on the diffusion of magnesium in aluminum during the heat treatment, the micro segregation in dendrites tends to decrease with the increase in both the heat temperature and the holding time. This phenomenon was confirmed by EPMA analysis. These results lead to the conclusion that the higher hardness in the weld metal than that of A5052-O base metal is caused by the micro segregation of magnesium in dendrites.

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Influence of Ti and N on strength and toughness of base plate and HAZ in 780MPa class steels with ultra-heavy thickness of over 150mm was examined using a thermal-cycle simulator.
(1) Relationship between Ti content and mechanical properties of the base plate under as-quenched condition varies depending on N content. While, toughness of medium-N steels (N = 40ppm) is improved by adding Ti due to microstructural change, toughness of low-N steels (N = 20ppm) deteriorates with increasing Ti content due to precipitation hardening by TiC.
(2) Influence of Ti and N on simulated HAZ toughness is more significant for double cycle condition than that for single cycle. Ti addition gives remarkable improvement in simulated HAZ toughness of the medium-N steels for double cycle condition. On the other hand, simulated HAZ toughness of the low-N steels deteriorates with increasing Ti content. The governing factors of the simulated HAZ toughness in double-cycle condition are the same as those of the toughness of base plate.
(3) It is concluded that the low-N steel without Ti addition and medium-N steels with Ti addition of 0.005 0.01% attain both high simulated HAZ toughness and high strength and toughness of base plate.

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The relation between clinical diagnosis and histopathological diagnosis were discussed with stress laid on the following two items.
1. Statistic observation: Among 1253 patients who underwent a histopathological examination at the Dermatologic Clinic of Kyushu University during the 3 years from the 45 th to the 48 th of Showa (1970∼1973), a clinical diagnosis and a histopathological one agreed with each other in the case of 842 patients (67%), while a clinical diagnosis did not agree with a histopathological one in the case of 371 patients and making a final decision was withheld in the case of 40 patients. Almost the same result was obtained when I observed 531 histopathological examples at the Essen Dermatologic Clinic in West Germany about 1965. Each of the cases of diagnostic disagreements about skin disease was examined clinically and histopathologically. For example, the case which was diagnosed clinically as BCE was found to be histopahtologically Bowen's disease, N. pigmentosus, SCC, seborrheic keratosis, DLE, etc., while another case diagnosed histopathologically as BCE was shown to be clinically keratosis senilis, Bowen's disease, SCC, keratoacanthoma, malignant melanoma, lupus vulgaris etc.
2. Histology of the efflorescence : In order to make a histopathological diagnosis practically we must be familiar with not only each of the histopathological findings of skin disease but also the histological structure of various efflorescences, which fact shows one of the peculiarities observed in histopathology of the skin. In this essay I took papulae as an example. Papulae, excepting true neoplasm, can be classified histologically into the following 3 groups ; (1) epide-rmal papula, (2) cutane papula, (3) mixed papula. I picked out typical histological figures of these 3 groups and explained some of them referring to the relations between clinical problem in practice and differential diagnostic one.

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  Ductile cast iron and mild steel were brazed with pure copper fillers using a high frequency induction heating with Ar atmosphere and a furnace heating with vacuum atmosphere. During brazing, rod-like crystals of Fe-Cu-C alloy precipitated at the cast iron side, and they grew toward the steel corresponding to the simultaneous dissolution of the steel. Length of rod-like crystal (L_A) and width of bonded zone (W_B) increased with an increase in both the bonding temperature and the holding time. After the crystals reached the steel, pearlite layer began to form in the steel because of diffusion of carbon in the cast iron through the crystal to the steel. Bond-strength (τ_B) increased with an increase in both the bonding temperature and the holding time. Under the same bonding condition, τ_B enlarged as the thinner filler metal was used. It was found that τ_B increased in proportion to the ratio (G_A) of L_A to W_B and that the larger the W_B, the lower the τ_B at G_A = 100 %.

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  In order to develop wear resistant grizzly plates for sintered ore screening process, a commercial hypereutectic high chromium cast iron containing Nb and V carbides was surfaced by self-shielded tubular-cored arc welding to 32mm thick, 350mm wide and 1000mm long SS400 plates. First, Abrasive Waterjet (AWJ) machinability was investigated using the surfaced SS400 specimens of various thickness, then the abrasion resistance of the deposited metals and conventionally used material was reviewed.
  The durability of the newly developed grizzly plates surfaced to 1000mm square SCW490 base metal and machined by AWJ was assessed under the impact and abrading of sintered ore, and compared with conventional cast plates. The main results obtained were as follows ;
  (1) When surfacing was carried out with a single torch, transverse cracks generated considerably. On the other hand, the cracks reduced markedly with two-torch surfacing.
  (2) The deposited metal showed good abrasion resistance. The AWJ maximum traverse rate however reduced to about half that of SS400 plate.
  (3) AWJ machinability significantly reduced when the abrasive waterjets traversed across the cracks, forming uncut zones beneath the cracks by the deflection of the jets.
  (4) The newly developed grizzly plates showed about four to six times more durability, while the conventional cast plates only last a couple of months.
  (5) Presently, the newly developed grizzly plates are seen to be replacing conventional ones in the plant.

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Continuous process of welding and heat treatment using a laser is proposed. The process begins with the welding stage where the laser irradiates in pulse mode at the optimized power so as to minimize the heat affected zone (HAZ). Next, to improve the mechanical characteristics of the HAZ. The temperature during the heat treatment is controlled by the laser power, the scanning speed, and the number of laser scans. Therefore this is a continuous process completed in a short time. This process is applied in the joining of dissimilar materials (spheroidal graphite cast iron and ferritic stainless steel) that are used in the exhaust components of automobile engines. Observations of the weld specimen with a microscope showed the formation of high carbon hardened martensite in the HAZ of the cast iron. The ratio of the welding joint strength to the spheroidal graphite cast iron strength was 69% (343MPa). Then using the heat treatment, the martensite was transformed into troosetite. After the continuous processing (1 laser scan) the joint strength became 82% (408MPa). The trial weld of the car engine exhaust part passed the thermal fatigue test of the engine bench test.

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