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Spheroidal graphite cast iron is often used for machine parts that require high strength. A shrinkage cavity may be generated inside the cast iron during the manufacturing process. If there is a shrinkage cavity in the cast iron, the strength of the cast iron is significantly reduced. In this article, a non-destructive testing method for detection of shrinkage cavity inside the cast iron by constant frequency vibration measurement using electromagnetic force excitation at low frequency is proposed. In this method, the electromagnetic force vibration is generated inside the cast iron from the static magnetic field by a permanent magnet and the eddy current by an alternating exciting coil. Then, the vibration is measured by an accelerometer that is in contact with the surface of the cast iron material. If there is a shrinkage cavity inside the cast iron, since the vibration intensity is changed, the shrinkage cavity is estimated by the vibration measurement. In this method, the shrinkage cavities inside cast iron can be inspected at high speed with an inexpensive device. In this article, the electromagnetic force vibration is calculated using the 3-D nonlinear electromagnetic finite element method (FEM) analysis. The displacement due to vibration in the cast iron is calculated by the 3-D displacement FEM analysis. The phenomenon of electromagnetic force excitation is clarified using these FEM analysis methods. Then, the effectiveness of the proposed inspection method is investigated by comparing the results of the verification experiment and analysis. [ABSTRACT FROM AUTHOR]

The interaction of HCl with the D2O-ice surface has been investigated in the temperature range 15–200 K by utilizing time-of-flight secondary ion mass spectroscopy, temperature-programmed desorption, and x-ray photoelectron spectroscopy. The intensities of sputtered H+(D2O) and Cl- ions (the H+ ions) are increased (decreased) markedly above 40 K due to the hydrogen bond formation between the HCl and D2O molecules. The HCl molecules which form ionic hydrates undergo H/D exchange at 110–140 K and a considerable fraction of them dissolves into the bulk above 140 K. The neutral hydrates of HCl should coexist as evidenced by the desorption of HCl above 170 K. They are incorporated completely in the D2O layer up to 140 K. The HCl molecules embedded in the thick D2O layer dissolve into the bulk, and the ionic hydrate tends to segregate to the surface above 150 K. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

TOF-SIMS is used to investigate the interactions between D[sub 2]O and hydrophobic molecules, such as CH[sub 4], CH[sub 3]F, CH[sub 2]F[sub 2], CHF[sub 3], and CF[sub 4], at cryogenic temperatures (15 K). By irradiation with a 1.5-keV He[sup +] beam, the D[sup +](D[sub 2]O)[sub n] ions are ejected efficiently from the D[sub 2]O nanoclusters physisorbed on the CF[sub 4] layer due to Coulomb explosion: the ion yields are by about two orders of magnitude higher than those from a thick D[sub 2]O layer via the kinetic sputtering. The D[sup +](D[sub 2]O)[sub n] yields decrease on the CH[sub n]F[sub 4-n] layer with increasing the number of the C–H group. This is because the Coulombic fission is quenched due to the delocalization of valence holes through the C–H...H–C and C–H...D[sub 2]O contacts. A pure D[sub 2]O film is hardly grown on the CH[sub 4] layer as a consequence of intermixing whereas the D[sub 2]O molecules basically adsorb on the surfaces of fluoromethanes, suggesting the attractive (water-repellent) interactions in the C–H...D[sub 2]O (C–F...D[sub 2]O) contacts. The C–H...O bond behaves like a conventional O–H...O hydrogen bond as far as the collision-induced proton transfer reaction is concerned. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Electron emission properties of Spindt-type platinum field emission cathodes were investigated. The current–voltage characteristics together with the current fluctuation during long term operation were evaluated in ultrahigh vacuum. The changes of the emission properties in hydrogen, oxygen or carbon monoxide gas ambient were also investigated. Significant improvement of the emission properties was found when the cathode was operated in carbon monoxide ambient under a certain condition. It was found that the effect of the improvement lasted at least 200 h, and resistance against the oxygen exposure was also improved. The changes of the electron emission properties during long term operation in ultrahigh vacuum and in gas ambient were analyzed with the Seppen–Katamuki chart, of which ordinate and abscissa are slope and intercept of Fowler–Nordheim plot. The electron emission properties were distributed along a straight line in the Seppen–Katamuki chart, and those of the cathode improved by carbon monoxide exposure were distributed along another line. The deviation of the electron emission property in ultrahigh vacuum was considered to be due to change in the geometry of the emitting surface. The major reason for the modification of electron emission properties in carbon monoxide ambient was considered to be deposition of carbon onto the emitting surface, resulting in reduction of the work function. From the deviation of the Fowler–Nordheim characteristics in the Seppen–Katamuki chart, we presented an empirical equation for field emission. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The interactions between condensed molecules at cryogenic temperatures (15–200 K) have been investigated on the basis of secondary ion mass spectrometry. It is demonstrated that the protonated molecular ions, emitted via the proton transfer reactions, provide us unique information about the reorganization of hydrogen-bonded molecules. From the CH[sub 3]OH molecules adsorbed on the D[sub 2]O–ice surface, the D[sup +](CH[sub 3]OH) ions are sputtered predominantly in the temperature range between 100 and 150 K since most of the CH[sub 3]OH molecules are bound to the D[sub 2]O layer via hydrogen bonds. A rapid and almost complete H/D exchange, yielding the D[sup +](CH[sub 3]OD) species, occurs above 150 K due to the enhanced mobility of the surface D[sub 2]O molecules. Up to the desorption temperature of 180 K, a considerable amount of methanol exists on the surface without mixing with the heavy-water layer due to hydrophobicity of the methyl group. On the methanol–ice surface, the adsorbed D[sub 2]O molecules form hydrogen bonds preferentially with the CH[sub 3]OH molecules and tend to be incorporated in the thin-layer bulk of methanol above 120 K. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

For non-destructive inspection of ferromagnetic pipes using magnetic flux leakage (MFL), a sensor consisting of two coils to measure the discrete Fourier sine and cosine coefficients of MFL is developed. The position of a crack in a pipe can be estimated from the squared sum and the ratio of the voltages induced in the two coils. Each coil has sixteen elemental coils with 78 permalloy cores which are placed along a circle with a radius of 6.3mm and connected in series. The number of turns comprising an elemental coil at an angle ϕ is proportional to sin ϕ in one coil and proportional to cos ϕ in the other. It was experimentally shown that a circular crack 4mm in diameter in a ferromagnetic pipe with diameter 21.6mm was localized. The proposed structure is suitable for narrow pipe inspection where the sensitivity of our previous sensor composed of two coaxial crescent-shaped coils decreases [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate genetic correlations between milk yield, somatic cell score (SCS), mastitis, and claw and leg disorders (CLDs) during first lactation in Holstein cows by using a threshold–linear random regression test-day model. We used daily records of milk, fat and protein yields; somatic cell count (SCC); and mastitis and CLD incidences from 46 771 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2000 and 2009. A threshold animal model for binary records (mastitis and CLDs) and linear animal model for yield traits were applied in our multiple trait analysis. For both liabilities and yield traits, additive genetic effects were used as random regression on cubic Legendre polynomials of days on milk. The highest positive genetic correlations between yields and disease incidences (0.36 for milk and mastitis, 0.56 for fat and mastitis, 0.24 for protein and mastitis, 0.32 for milk and CLD, 0.44 for fat and CLD and 0.31 for protein and CLD) were estimated at about the time of peak milk yield (36 to 65 days in milk). Selection focused on early lactation yield may therefore increase the risk of mastitis and CLDs. The positive genetic correlations of SCS with mastitis or CLD incidence imply that selection to reduce SCS in the early stages of lactation would decrease the incidence of both mastitis and CLD. [ABSTRACT FROM PUBLISHER]

We investigated the relationships between conception rates (CRs) at first service in Japanese Holstein heifers (i.e. animals that had not yet had their first calf) and cows and their test-day (TD) milk yields. Data included records of artificial insemination (AI) for heifers and cows that had calved for the first time between 2000 and 2008 and their TD milk yields at 6 through 305 days in milk (DIM) from first through third lactations. CR was defined as a binary trait for which first AI was a failure or success. A threshold-linear animal model was applied to estimate genetic correlations between CRs of heifers or cows and TD milk yield at various lactation stages. Two-trait genetic analyses were performed for every combination of CR and TD milk yield by using the Bayesian method with Gibbs sampling. The posterior means of the heritabilities of CR were 0.031 for heifers, 0.034 for first-lactation cows and 0.028 for second-lactation cows. Heritabilities for TD milk yield increased from 0.324 to 0.433 with increasing DIM but decreased slightly after 210 DIM during first lactation. These heritabilities from the second and third lactations were higher during late stages of lactation than during early stages. Posterior means of the genetic correlations between heifer CR and all TD yields were positive (range, 0.082 to 0.287), but those between CR of cows and milk yields during first or second lactation were negative (range, −0.121 to −0.250). Therefore, during every stage of lactation, selection in the direction of increasing milk yield may reduce CR in cows. The genetic relationships between CR and lactation curve shape were quite weak, because the genetic correlations between CR and TD milk yield were constant during the lactation period. [ABSTRACT FROM PUBLISHER]

The transcription factor E2F1 has pivotal roles in both cell proliferation and cell death, and is an important molecular target in cancer. Under proliferative conditions E2F1 induces the expression of genes that promote cell cycle progression, such as E2F2, whereas under proapoptotic conditions E2F1 induces expression of genes such as p73 that lead to apoptosis. The mechanism by which the apoptotic function of E2F1 is activated remains unclear, however. We now show that members of the E2F family are covalently conjugated with the ubiquitin-like modifier NEDD8. Overexpression of SENP8, a NEDD8-specific cysteine protease, resulted in deNEDDylation of E2F1 and promoted its transactivation activity at the p73 gene but not at the E2F2 gene. Knockdown of SENP8, on the other hand, attenuated p73 expression and apoptosis induced by E2F1 or by DNA damage. SENP8 also promoted the interaction between E2F1 and its cofactor Microcephalin 1, which is required for p73 induction. These results suggest that NEDDylation is a molecular trigger that modifies the target specificity of E2F1, and could have important implications for E2F1 regulation of apoptosis. [ABSTRACT FROM AUTHOR]

The inspection of the hardened depth of surface-hardening steel is important in the maintenance of various mechanical parts, and for other purposes as well. There is a difference in the electromagnetic properties in the layers with and without hardening. Therefore, the evaluation of the hardened depth is possible by detecting the difference in the electromagnetic characteristics. In this paper, the electromagnetic method for measuring the depth of a hardened layer using an alternating magnetic field of low frequency is proposed. The flux density in the surface-hardening steel is estimated by a 3-D nonlinear finite-element method taking account of the hysteresis characteristics of the layers with and without hardening. In addition, the experimental verification is also carried out. [ABSTRACT FROM AUTHOR]

Steel tubes are used in the heat exchanger in the petrochemical plant or the steam generator in the fast breeder reactor. Since these steel tubes in the heat exchanger or steam generator are stored as a bundle by the support steel plate (baffle), it is necessary to inspect the existence of defects from the inside of each tube. In these steel tubes, the defects are generated between the steel tube and the baffle at the outer side of steel tube. In this paper, problems in applying the alternating flux leakage testing method for the inspection of the outer side defect on steel tube with the baffle are examined using 3-D nonlinear FEM. Moreover, the differential type search coils that detect the leakage flux from the outer side defect on steel tube are proposed. The optimal dimension of the differential search coils is determined using the Rosenbrock's method or the evolution strategy. [ABSTRACT FROM PUBLISHER]