Estimation of springback of stainless steel sheet part taking influence of anisotropic property of plastic-deformation-dependent young's modulus into account

A kinematic hardening model proposed by Yoshida and Uemori (Y-U model) was applied to the prediction of springback of stainless steel sheet part. From the experiments for the determination of the material constants, an anisotropic property of change in Young’s modulus was observed; namely, the anisotropy was different at 0°, 45° and 90° from the rolling direction. The Y-U model for the stainless steel sheet was used to a calculation of a forming process of a part to examine the accuracy of the prediction of the springback by compar-ing the calculated result with the actual part formed. In order to consider the anisotropic property of change in Young’s modulus, the calculated result to the actual part formed. In order to consider the anisotropic property of the change in Young’s modulus, the calculations were performed using the different material constants at 0°, 45° and 90° from the rolling direction. With the material constants at 90° from the rolling direction, which was the direction of springback of the part, the prediction accuracy can be improved. Therefore, the consideration of the anisotropic property of the change in Young’s modulus was found to be effective for more accurate prediction of the springback of the stainless steel part

AJK2011-09012 INFLUENCE OF WATER-SPLASH FORMATION BY A HYDROPHILIC BODY PLUNGING INTO WATER

ABSTRACT The objective of this study is to understand the relationship between water-splash formation and the surface conditions of bodies plunging into the water's surface by considering hydrophilicity strength. A hydrophilic body (constructed with hydrogel), as well as an acrylic resin body, was created to understand the influence of hydrophilicity on splash formation. The strength of hydrophilicity was determined by investigating degrees of swelling. We obtained consecutive images of splash formation by using a high-speed CMOS camera. We show that water-splash formation is related to water-film formation by studying: 1) droplets formed at the film edge, 2) mushroomor dome-type splashes caused by film impinging, and 3) crowntype splash caused by film separation. The strength of hydrophilicity affects the splash-formation process of the mushroom-and crown-type splashes. The difference in formation process is caused when the film velocity increases with hydrophilicity. As the film velocity increases with strong hydrophilicity, the film flow separates from the body surface and an air cavity forms. Crown-type splashes form with hydrophilic bodies because such film separation occurs. Moreover, the relationship between the strength of hydrophilicity and film velocity was examined empirically. These results indicate that the hydrophilic body does not alter the splash-formation process. INTRODUCTION This study experimentally investigates the splash formed when a solid body plunges into water focusing on the influence of a hydrophilic body on subsequent splash events. The body impact on the water surface during a seaplane landing was studied by vo

A Candidate Active Galactic Nucleus with a Pure Soft Thermal X-ray Spectrum

We report the discovery of a candidate active galactic nucleus (AGN), 2XMM J123103.2+110648 at z = 0.13, with an X-ray spectrum represented purely by soft thermal emission reminiscent of Galactic black hole (BH) binaries in the disk-dominated state. This object was found in the second XMM serendipitous source catalogue as a highly variable X-ray source. In three separate observations, its X-ray spectrum can be represented either by a multicolor disk blackbody model with an inner temperature of kT_in~0.16-0.21 keV or a Wien spectrum Comptonized by an optically thick plasma with kT~0.14-0.18 keV. The soft X-ray luminosity in the 0.5--2 keV band is estimated to be (1.6-3.8)x10^42 erg/s. Hard emission above ~2 keV is not detected. The ratio of the soft to hard emission is the strongest among AGNs observed thus far. Spectra selected in high/low flux time intervals are examined in order to study spectral variability. In the second observation with the highest signal-to-noise ratio, the low energy (below 0.7 keV) spectral regime flattens when the flux is high, while the shape of the high energy part (1-1.7 keV) remains unchanged. This behavior is qualitatively consistent with being caused by strong Comptonization. Both the strong soft excess and spectral change consistent with Comptonization in the X-ray spectrum imply that the Eddington ratio is large, which requires a small BH mass (smaller than ~10^5M_solar.Comment: To Appear in ApJ, 8 pages, 7 figure

Direct TEM Observation of Vacancy-Mediated Heteroatom Incorporation into a Zeolite Framework: Towards Microscopic Design of Zeolite Catalysts

Incorporating hetero-metal-atom,e.g., titanium, into zeolite frameworks can enhance the catalytic activity and selectivity in oxidation reactions.However,the rational design of zeolites containing titanium at specificsites is difficult because the precise atomic structure during synthesis process remained unclear.Here, a titanosilicate with predictable titanium distribution was synthesized by mediating vacancies in a defective MSE-typezeolite precursor,based on a pre-designed synthetic route including modification of vacancies followed by titanium insertion,where electron microscopy(EM) plays a key role at each step resolving the atomic structure.Point defects including vacancies in the precursor and titanium incorporated into the vacancy-related positions have been directly observed. The results provide insights into the role of point defects in zeolites towards the rational synthesis of zeolites with desired microscopic arrangement of catalytically active sites

A bacterial enzyme degrading the model lignin compound β-etherase is a member of the glutathione-S-transferase superfamily

AbstractCleavage of β-aryl ether linkages is essential in lignin degradation. We identified another β-etherase gene (ligF), which contains an open reading frame of 771 bp and lies between genes coding Cα-dehydrogenase (ligD) and β-etherase (ligE). The β-etherase activity of LigF expressed in Escherichia coli was more than 80 times as high as that of LigE. ligF and ligE are homologous to glutathione-S-transferase, and upon addition of glutathione a remarkable acceleration of β-etherase activity was found in E. coli carrying ligF. It is concluded that LigF plays a central role in β-aryl ether cleavage and that glutathione is the hydrogen donor in this reaction

AJK2011-03076 EFFECTS OF WALL CONDITION OF A PLUNGING BODY ON SPLASH

ABSTRACT Splashes generated by hydrogel sphere were simulated numerically and experimentally for investigating the effects of slip like mucus of living things. Numerical simulation using MPS (Moving Particle Semi-implicit) method was carried out. We defined the slip ratio as the swelling degree of hydrogel and installed the slip ratio into the MPS method. The swelling degree is the ratio of the weight of water against that of hydrogel. We simulated the splashes generated by the hydrogel spheres which had the different swelling degree plunging into water. As the evaluation of swelling degree on the surface of actual hydrogel spheres we also tested by using the hydrogel spheres plunging into water experimentally. The height of splash as a result of reaction of the air cavity became higher according to the increase of the swelling degree. The speed of hydrogel sphere sinking in water tank was also quicker in the numerical simulation. The reason of these results was that the velocity of water around the hydrogel sphere became quicker due to the slip on the surface