Influence of Addition of Nickel on the Thermal Expansion, Rigidity Modulus and Its Temperature Coefficient of the Alloys of Cobalt, Iron and Chromium, Especially of Co-Elinvar. II : Additions of 30 and 40 per cent of Nickel

The influence of additions of 30 and 40 per cent of nickel on the thermal expansion in the range from 10 to 50°, rigidity modulus at 20°and its temperature coefficient in the range from 20 to 50°of the alloys of cobalt, iron and chromium was studied. The relations between those properties and the concentrations of nickel-added alloys were almost similar qualitatively to those in the case of the ternary alloys of cobalt, iron and chromium, that is, there were two groups of alloys, one showing a positive temperature coefficient of rigidity modulus and the other a negative. And it has been found that the content of cobalt at the composition showing the smallest value of the coefficient of thermal expansion and the largest positive maximum of the temperature coefficient of rigidity modulus decreases with the increase of nickel content and finally reaches zero at the composition of invar in the binary system of nickel and iron, while the content of chromium does not change until that of nickel reaches about 15 per cent, then gradually decreases and becomes zero at the composition of about 30 per cent of nickel and the rest of iron. In the case of addition of 30 per cent of nickel, the smallest thermal expansion coefficient was 1.87×10^, while in the case of addition of 40 per cent, it was 0.54×10^. The largest positive values of the temperature coefficient of rigidity modulus in the corresponding cases were respectively +76.4×10^ and +81.0×10^. The largest and smallest values of rigidity modulus in the case of addition of 30 per cent of nickel were 7.84×10^kg/cm^2 and 4.55×10^kg/cm^2, and in the case of 40 per cent of nickel they were respectively 8.96×10^kg/cm^2 and 4.69×10^kg/cm^2

Thermal Expansion Coefficient, Rigidity Modulus and Its Temperature Coefficient of the Alloys of Iron, Nickel, Cobalt and Chromium, and Relations of Super Invar to Stainless Invar and of Elinvar to Co-Elinvar

The influence of an addition of chromium on the thermal expansion, rigidity modulus and its temperature coefficient of the alloys of iron, nickel and cobalt has been determined. It has been found that, in the relations of the thermal expansion cofficient or the temperature coefficient of rigidity modulus to the concentration of the alloys of iron, nickel, cobalt and chromium, there are two ranges of the minimum values of the expansion coefficient or the maximum values of the positive temperature coefficient of the modulus, one of which originates at the composition of invar, that is, in the neighbourhood of the composition of super invar, or elinvar in the binary system of iron and nickel, and the other at those of stainless invar or co-elinvar in the ternary system of iron, cobalt and chromium ; they come together at the section of 10 per cent of chromium of the quaternary system, showing that stainless invar or co-elinvar are closely connected respectively with invar (super invar) or elinvar, and also that the nickel and the cobalt contained in each alloy can be substituted almost linearly by each other

New Elinvar-type Alloy "Tungelinvar" in the Ternary System of Cobalt, Iron and Tungsten, and the Characteristics Dependent on the Addition of Nickel

According to the rule of the small expansibility of invar proposed previously by one of the present authors it was proposed that there are some alloys of invar and elinvar type in the cobalt, iron and tungsten system and in the quaternary system containing nickel besides these. So, the thermal expansion coefficient, the rigidity modulus and its temperature coefficient were examined with the ternary and the quaternary alloys mentioned above in annealed state. It was found that the temperature coefficient of rigidity modulus showed a negative minimum value of -0.7×10^ at the composition having the minimum thermal expansion coefficient of 7.39×10^ in the ternary system ; the figures of the curves of temperature coefficient of the modulus were almost the same as those obtained previously with alloys containing cobalt, iron and chromium, cobalt, iron and vanadium, and also cobalt, iron and molybdenum with the exception that the present alloys did not show any positive coefficient. But, it has been proved that there are some alloys of invar and elinvar type in this ternary system as expected. When 10 percent of nickel was added to the ternary alloys, the range showing positive temperature coefficient of the modulus began to appear. With the increase of nickel content, the minimum value of the thermal expansion coefficient became small and the positive maximum value of the temperature coefficient of the modulus larger, and the composition at which these special characteristics were observed shifted toward the side of low cobalt and low tungsten, finally reaching 36 percent of nickel in the binary system of iron and nickel, showing the same effect as case of nickel being added to the alloys of cobalt, iron and chromium, cobalt, iron and vanadium, and cobalt, iron and molybdenum. These new ternary and quaternary alloys having small temperature coefficient of the modulus have been named "Tungelinvar"

Influence of Addition of Copper on the Characteristics of an Elinvar Type Alloy "Co-Elinvar". I : Alloys Containing 5 per cent of Copper

The influence of an addition of 5 per cent of copper on the thermal expansion, rigidity modulus and its temperature coefficient of the alloys of cobalt, iron and chromium has been determined. The relations between the thermal expansion coefficient or the temperature coefficient of rigidity modulus of copper-added alloys and the concentrations are qualitatively similar to those of the ternary alloys of cobalt, iron and chromium, but the relation in the case of rigidity modulus is more complicated than in the case of the ternary alloys. The compositions, at which the thermal expansion coefficient shows the smallest value and the temperature coefficient of the modulus the largest positive value, do not show any remarkable change with the addition of copper. When copper is added, the concentration range having the positive temperature coefficient of the modulus becomes comparatively narrower. Some elinvar type alloys containing comparatively high chromium have larger rigidity modulus than 8×10^5kg/cm^2, showing an important characteristic for a practical application

Surface Modification of Fluorocarbon Polymer Film by High Density Microwave Plasma

金沢大学理工研究域サステナブルエネルギー研究センタ

Tumor suppressor REIC/Dkk-3 interacts with the dynein light chain, Tctex-1

Persistent hepatitis C virus (HCV) infection causes chronic liver diseases and is a global health problem. HuH-7 hepatoma-derived cells are widely used as the only cell-based HCV replication system for HCV research, including drug assays. Recently, using different hepatoma Li23-derived cells, we developed an HCV drug assay system (ORL8), in which the genome-length HCV RNA (O strain of genotype 1b) encoding renilla luciferase replicates efficiently. In this study, using the HuH-7-derived OR6 assay system that we developed previously and the ORL8 assay system, we evaluated 26 anti-HCV reagents, which other groups had reported as anti-HCV candidates using HuH-7-derived assay systems other than ORB. The results revealed that more than half of the reagents showed different anti-HCV activities from those in the previous studies, and that anti-HCV activities evaluated by the ORB and ORL8 assays were also frequently different. In further evaluation using the HuH-7-derived AH1R assay system, which was developed using the AH1 strain of genotype 1b, several reagents showed different anti-HCV activities in comparison with those evaluated by the OR6 and ORL8 assays. These results suggest that the different activities of anti-HCV reagents are caused by the differences in cell lines or HCV strains used for the development of assay systems. Therefore, we conclude that plural HCV assay systems developed using different cell lines or HCV strains are required for the objective evaluation of anti-HCV reagents

New Ferromagnetic State Observed during Recrystallization and Induced Magnetic Anisotropy of Cold-Rolled Ferromagnetic γ-phase Alloy

With measurements of the magnetization and the magnetic anisotropy at room temperature after annealing at various temperatures, magnetic analysis was performed on a ferromagnetic γ-phase alloy which was cold-rolled by 50～90% and consisted of 27 per cent cobalt, 9 per cent chromium, 17 per cent nickel and iron in balance. It was found that the volume of the α-phase produced by cold rolling and its Curie point were changed by the reduction, and that a new ferromagnetic phase appeared at 550°～650℃. This new phase was not observed after recrystallization, becoming larger as the reduction advanced, and remained at room temperature. The positive uniaxial anisotropy induced by cold rolling changed its sign after the treatment at 300°～500℃, and a negative maximum value was obtained after the treatment at 550°～600℃, accompanying the appearance of negative crystal anisotropy. The change in the magnetization curve by the treatment was also in parallel with that in the uniaxial anisotropy mentioned above. These results were explained clearly by the formation of twins and the coagulation of some components on slip planes