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Surface tension of a coal extract in an organic solvent; Sekitan chushutsu seibun no kaigo to hyomen choryoku  

Energy Technology Data Exchange (ETDEWEB)

The behavior and properties of associated bodies were studied through measurement of surface tension considering acetone-soluble fraction relatively light among various solvent extracts of coal. In experiment, the acetone-soluble fraction was extracted from the substances extracted from Upper Freeport coal as standard specimen using the mixed solvent of carbon disulfide (CS2) and N-methyl-2-pyrrolidinone (NMP), and it was dissolved into NMP after drying. Surface tension was measured by Wilhelmy method. The experimental results are as follows. Equilibrium surface tension is equal to the surface tension of pure solvent in a low concentration range of solution, and decreases with an increase in concentration approaching a fixed value at 0 in log concentration, nearly showing an S curve. Adsorption of species with non-polar aromatic ring of the acetone-soluble fraction on a solution surface probably decreases surface tension. Change with time in surface tension is observed which suggests ...

1996-10-28

2

Rotation seismic sensor and its calibration; Kaiten seibun jishinkei no shisaku to kando no kentei  

Energy Technology Data Exchange (ETDEWEB)

Sensor has been developed for the measurement of seismic wave rotary components. The vertical axis rotary component sensor is constituted of four L22Ds, similar to each other in performance, fixed in a ring formation on a metal bed. The ring is 22cm in diameter, and the four coils are connected so that their outputs will be added up. A horizontal axis rotary component sensor is built in the similar way. The rotary component sensors are all connected to a spectrum analyzer for the measurement of micromotions. It is found that the four-L22D combination can detect a rotary component of 335mV/deg/s. The sensor can detect both vertical and horizontal components with roughly the same sensitivity. A ring-form combination of conventional electromagnetic seismometers, though only as a temporary expedient, can perform high-resolution detection of rotary components and determine the absolute values of earthquakes or noise levels. In the case of a gyrosensor available on the market, its resolution ...

1997-05-27

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Effects of comonomer and two-step oxidation on production of polyacrylonitrile-based carbon fibers. Polyacrylonitrile kei tanso sen'i no seizo ni okeru sanka jikan ni oyobosu zenkutai sen'i no kyojugo seibun oyobi dankai sanka no koka  

Energy Technology Data Exchange (ETDEWEB)

The oxidation conditions were investigated for obtaining a higher productivity in the production of high strength carbon fiber from polyacrylonitrile (PAN). The effect of incorporation of 2 % comonomer such as methyl acrylate (MA), acrylate containing carboxylate (SA), acrylamide (AAm), and hydroxyethyl acrylate (HEA) on the oxidation conditions was also investigated. The measurement of DSC and bonded oxygen content revealed that the most effective comonomer for promoting the cyclization of nitril group and the bonding of oxygen was found to be SA, and the second best was AAm. The measurement of tensile strength of carbon fiber showed that the copolymer of SA, HEA, and MA gave a high strength fiber. It took a long time to oxidize the carbon fiber when it was oxidized at a temperature on which double layer structure was not formed. To shorten the production time, a method of combining the upper limit oxidation in which the double layer structure was not formed and the second oxidation ...

1994-06-10

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Behavior of inert gas contamination in high Ni alloy powder and consolidation powder material; Ko Ni gokin funmatsu funmatsu seikeitai ni okeru fukassei gas seibun no kyodo  

Energy Technology Data Exchange (ETDEWEB)

Inert gas contamination, structure and mechanical properties of consolidated high-Ni alloy powder material were studied to improve its characteristics. In experiment, the chemical composition and fraction of porosity in cross sections of Alloy 625 powder were examined which was produced by Ar gas atomization method impinging supplemental gas jet onto accumulated alloy powder in the bottom of a tank for rapid cooling. The structure and mechanical properties of the alloy rod were also examined which was produced by hot hydrostatic pressing or hot extrusion of the powder filled into a capsule. As a result, although Ar content included in the powder produced by Ar gas atomization method decreased with reduction in grain size, the fine powder less than 22{mu}m still included Ar of nearly 0.5mass-ppm. Obvious correlation was found between the fraction of porosity in powder cross sections and Ar in the powder. Although cavities were detected in the consolidated powder material produced by hot ...

1996-07-01