A study has been made of the effect of hydrogen on the shape memory effect and transformation behavior of Ti-Ni alloy. The material was evaluated in the temperature range from 300 to 473 K using a bent specimen. The transformation behavior was analyzed by differential scanning calorimetry (DSC) and X-ray diffraction technique.
The results obtained are as follows:
(1) The shape recovery rate is markedly decreased by a small amount of hydrogen which does not cause the increase in hardness.
(2) The shape recovery occurs even below the transformation temperature (As) in the material charged with hydrogen for a relatively long time, resulting from a hydride formation.
(3) It is found that the hydrogen causes a considerable decrease in the heat of the transformation and only a slight decrease in the transformation temperature.
(4) The heat of transformation and the transformation temperatures before hydrogenation is restored by holding the hydrogenated material at 753 K for 300 s.
(5) Two types of the hydrides form during charging at a current density of 1000 A/m².

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In order to clarify the effects of heat treatments and thermal cycles on helical spring properties which are essential to practical use, spring (force-temperature) test, differential scanning calorimetry (DSC) and X-ray diffraction measurement have been performed on Ni_48.9-xTi_50.2Cu_x alloys.
The force-temperature curve was measured at a constant spring height and the shear modulus G_303K and G_363K were calculated from the force on the curves at 303K and 363K, respectively. The G_303K at the martensitic phase was 0GPa in either case of annealing at 673 and 773K, having a tendency of increasing with rise in annealing temperature of 873 and 973K. Meanwhile, the G_363K at the parent phase with a value of G_363K=20 to 30GPa was not affected by annealing temperature. Transformation temperature was increased with rise in annealing temperature, but transformation range (Af-Mf) temperature did not agree between the spring test and DSC measurement. The (Af-Mf) temperature was about 20K on the former and about 40K on the latter. Thermal cycles of 5000 times between 293 and 363K resulted in decrease in the force of the spring and the ratio of the force at 363K after the 5000 cycles to no cycle showed a tendency to decrease with rise of annealing temperature and increase with rise of Cu concentration.
X-ray diffraction measurement made it clear the martensitic phase was monoclinic system in X=7 and orthorhombic system in X=10, 12.

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ショナ族は祖霊「ムズィム」(mudzimu)を信仰の対象とする。特に父系クランのムズィムは霊としてその子孫を守ると考えられている。ムズィムは憑依を通じて子孫と会話をおこなう。元首長のムズィムは、クランの政治的指導者としても重要な役割を果たしてきた。本発表では、ムズィムの概念を喪明け・相続の儀礼「クロワグワ」(kurova guva)から考察する。この儀礼において死者のムズィムが清められ、家族のもとに霊として迎えられる。

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Effects of nitrogen on microstructure and phase transformation temperatures were investigated for near-equiatomic Ti-Ni shape memory alloys arc-melted in Ar-N₂ atmospheres. The nitrogen content in the arc-melted specimens increased with increasing melting time and rising nitrogen partial pressure in atmosphere (arc current 150A, arc voltage 12V, specimen weight 12 g and melting time 0-480 s). With increasing nitrogen content, the amount of second phase observed in arc-melted specimen increased. The second phase was identified as TiN by an electron probe microanalysis and an X-ray diffraction analysis. Both Ms and Af temperatures decreased with increasing nitrogen content of arc-melted specimen. The temperatures of Ms and Af were described by functions of nickel and nitrogen contents.

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The object of this article is to reexamine the theory of the Kunijitoshiki (国地頭職) in order to study the formation of the Shugo and Jito system within the Kamakura government. Since the discovery of the kunijitoshiki, the vast majority of previous studies have recognized its existence, that is to say, it has been an established theory that the content of the petition to the court in November in 1185, which was made by Hojo Tokimasa (北条時政), a messenger dispatched by Minamoto no Yoritomo (源頼朝), was the original kunijitoshiki. However, in this article the author attempts to examine the existence of the kunijitoshiki in itself, in the light of the confusibn of previous studies, especially on the relationship between the kunijitoshiki and sotsuibushi (惣追捕使). First, the author confirms the content of the petition. It is aimed principally at establishing sotsuibushi in the western provinces to track down Minamoto no Yoshitsune (源義経) and other outlaws. Furthermore, the following two rights petitioned for at the same time, the right to collect provision rice, and the right to dispose of mokkanryo (没官領) were based in the Sotsuibushi. Secondly, the author analyzes the content of the negotiations, between the court and Tokimasa in March in 1186. The analysis shows that the shichikakokujitoshiki (七カ国地頭職), which is regarded as the only concrete evidence for the existence of the kunijitoshiki, was a general name of the shogojitoshiki (荘郷地頭職) established in seven provinces. Thirdly, the author examines the kyukokujito (九国地頭), the shikokujito (四国地頭), and the Kamakuradonokannoshi (鎌倉殿勧農使), which are regarded as the direct predecessors of the kunijitoshiki, but were different from the kunijitoshiki in kind. On the basis of these examinations, the author denies the existence of a kunijitoshiki within the kamakura government. Therefore, it is not necessary to take account of the kunijitoshiki when studying the formation of the shugo and jito system of that Government.

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The effect of hydrogen on the cyclic shape memory behavior of Ti-Ni alloy has been studied. A cyclic test machine was constructed. As the result, shape memory recovery stress and recovery % decreased with a small amout of hydrogen absorption. After degasing of the hydrogen following the cathodic charge, recovery stress and recovery % approached the level of a hydrogen-free specimen. The rate of this approaching depended on the amount of cyclic strains. During deformations at martensitic phases, no effect of hydrogen was observed on the coalescence of martensite variants. The decrease in recovery stress under mild hydrogen conditions, in which no hydride has been formed, was attributed to interactions between mobile hydrogen and dislocation introduced by the cyclic deformations.

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Shape memory alloys are one of the new functional materials and they have a unique property which shows the shape recovery phenomena by heating after deformation. Many applications using shape memory effect are developing. TiNi shape memory alloy has excellent material properties among shape memory alloys. These shape memory effects are caused by thermoelastic martensitic transformation and reverse transformation.
The phase transformation temperatures in TiNi shape memory alloy were measured by adiabatic method, DSC and DTA. These temperatures were affected by many factors, such as Ni concentration, thermal cycling and substitution of Ni by third elements. Tini shape memory alloy transformed from martensite phase to parent phase by heating after solution treatment. By thermal cycling or substitution of Ni by third elements, intermediate phase was observed between martensite phase and parent phase. By heating, the CsCl type ordered structure of TiNi parent phase changed to the BCC disordered structure at high temperature.

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The present study was undertaken to apply the laser welding to the joining of a shape memory alloy. Butt welding of a Ti-Ni type shape memory alloy was performed using 10 kW CO₂ laser.
The laser welded specimens showed successfully the shape memory effect and super elasticity. These properties were approximately identical with those of the base metal. The change in super elasticity of the welded specimen during tension cycling was investigated. Significant changes in stress-strain curves and residual strain were not observed in the laser welded specimen after the 50-time cyclic test.
The weld metal exhibited the celler dendrite. It was revealed by electron diffraction analysis that the phase of the weld metal was the TiNi phase of B2 structure which is the same as the parent phase of base metal and oxide inclusions crystallized at the dendrite boundary. However, oxygen contamination in the weld metal by laser welding did not occur because there was almost no difference in oxygen content between the base metal and the weld metal. The transformation temperatures of the weld metal were almost the same as those of the base metal.
From these results, laser welding is applicable to the joining of the Ti-Ni type shape memory alloy. As the application of laser welding to new shape memory devices, the multiplex shape memory device of welded Ti-50.5 at%Ni and Ti-51.0 at%Ni was produced. The device showed two-stage shape memory effects due to the difference in transformation temperature between the two shape memory alloys.

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植物病原体の生育を抑制する植物保護細菌として，多くのPseudomonas属細菌株がP. fluorescnes種に分類されていた。近年，再同定が進められ，一部の菌株はPseudomonas protegensという新種として改めて登録された。本種の種名は，「植物を土壌病原体から守るもの」という意味である。本種については，多様な抗菌物質産生能や植物を含む生物間相互作用について詳細な解析が進んでいる。更に本種に属する菌株は植物保護細菌として初めてゲノム解読され，ゲノムマイニングによる新規機能発見などにつながった。本種は日本でも見出されており，植物土壌病害の生物的防除等での有効利用が期待される。

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Shape memory properties of Ti-Ni-Cu alloy under a mild hydrogen absorbing condition have been studied. Decreases in mechanical properties such as tensile strength and total elongation occurred because of hydrogen absorption. Critical value of hydrogen content for the decrease in mechanical properties was higher in comparison to Ti-Ni alloy. Decreases in shape recovery stress and recovery rate due to hydrogen absorption during the cyclic shape memory test were not as great as that of Ti-Ni alloy. These results were considered to be caused by relatively small plastic deformation and dislocations introduced during the cyclic test, resulting from small absorption content of hydrogen due to the presence of some protective surface layer. In conclusion, Ti-Ni-Cu alloy is suitable for applications in hydrogen environment, in comparison to Ti-Ni alloy.

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The purpose of the present paper is to clarify the movements of the vassals (hikan 被官) who served under the Rokuhara Tandai 六波羅探題, and therefore understand the significance of this representative of the Kamakura Bakufu stationed the capital of Kyoto. According to the principles for policing the capital, both Kamakura Bakufu vassals stationed in Kyoto (zaikyonin 在京人) and the Tandai's vassals were probably mobilized under the police commander (kendan tonin 検断頭人), who was also a vassal of the Tandai. Not only within the Capital itself, but also in the adjacent provinces of the Kinai region "Rokuhara's" policing activities were mainly executed by the same kendan tonin. And, it seems that other Rokuhara hikan, as well, were given authority to lead Kyotobased Kamakura vassals. This peacetime policing function of "Rokuhara" would take on the military posture of the "Rokuhara" army in times of crisis. And during these times as well both the kendan tonin and other authorized Rokuhara hikan would assume military leadership over zaikyonin. Moreover, whenever the Rokuhara Tandai held at the same time the Bakufu appointment of shugo (provincial constable), all of his hikan would also serve as deputy constables (shugo-dai 代). Especially in the Kinai region this rule greatly bolstered the power and authority of the Tandai. Essentially the position of Rokuhara Ryoshi 両使 was occupied by either a zaikyonin or a bugyonin 奉行人 (Bakufu functionary) ; however, during the last years of the Kamakura period Rokuhara Tandai vassals began to participate in the Ryoshi insititution through the form of ryoshi ippo shugo-dai 両使一方代 (Ryoshi cum deputy-constable). "Rokuhara" organized Kyoto-based Kamakura vassals as one link in its rule over Western Japan. One more step was its not always successful attempt to subsume zaikyonin and bugyonin personally under the Tandai as his hikan. From the above discussion, the author concludes that one important aspect of "Rokuhara" was its role as an institutional base for gaining control over the Western provinces by placing vassals tied to the Hojo family in key policing and military positions.

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