Coexistence of Vortex Liquid and Solid in Rotating Bose-Einstein Condensate

No Heading We perform computer simulations for the Gross-Pilaevskii equation with a tiny damping in order to study the condensate wave-function in 3-D rotating Bose-Einstein condensate under the trapping potential. We find that the wave-function is divided into two kinds of phases in terms of its coherent feature. The first one is a coherent phase which is characterized by the static vortex lattice located close to the center of the trapping potential, and the second one is an incoherent one which lies outside the first coherent phase and shows vortex liquid like behaviors. The boundary between the two phases is quite sharp like the phase interface as seen in the first-order phase transition. This result suggests that the melting seen in type II superconductors spatially occurs in the rotating Bose-Einstein condensate since the wave-function amplitude decreases with departing from the center of the trap and its coherent feature is overcome by intrinsic fluctuations at a certain distance.PACS numbers: 03.75.Lm, 03.75.Kk, 74.25.Qt, 74.40.+k     

Characterization of a novel gene disrupted by a balanced chromosomal translocation t(2;19)(q11.2;q13.3) in a family with cleft lip and palate

Paleodemographers must work to understand how representative any archaeologically recovered skeletal series is and the potential effects of series bias on their demographic reconstructions. We examine two forms of bias: 1) infant underenumeration caused by differential preservation or incomplete archaeological recovery and 2) the underenumeration of individuals over age 45 related to methodological bias. We generated 60 simulated skeletal series of 250 individuals each based on the Brass ([1971] Biological Aspects of Demography (London: Taylor and Francis), pp. 69-110) logit models. In the first test, age bias was introduced deterministically for all individuals with age at death over 40 years using the Lovejoy et al. ([1985] Am. J. Phys. Anthropol. 68:1-14) bias estimates. In the second test, 50% of all individuals under 5 years old were removed from each simulated distribution. The simulated series were analyzed using the model life table fitting procedure developed by the authors (Milner et al. [1989] Am. J. Phys. Anthropol. 80:49-58; Paine [1989] Am. J. Phys. Anthropol. 79:51-62). Forms of adult age estimation bias described by Lovejoy and coworkers inflate estimates by 10-20% of the true crude birth rate (CBR) (the number of births per year per 1,000 population). Overestimation of fertility and birth rates increases both absolutely and as a percentage of the true rate as population growth increases. This bias is very consistent. Because Lovejoy and colleagues have estimated the methodological bias itself, its effects can be estimated. Infant underenumeration is a more serious obstacle. It is not presently possible to estimate infant underenumeration reliably without prior knowledge of fertility rates. This reduces fertility reconstructions based on infant-biased samples to minimum fertility estimates.     

Products of Reaction Between PbO and Nb2O5 in Molten KCl or NaCl

Lead oxide and niobium oxide were heated in molten KCl or NaCl to examine the participation of chlorides in the reaction between the oxides. Alkali ions partially replace Pb ions in PbNb₂O₆, and Cl ions form PbCl₂. The substitution of alkali ions for Pb stabilizes the tetragonal form ofPbNb₂O₆. The reactivity of NaCl with Nb₂O₅ was much greater than that of KCl; the extended substitution resulted in the formation of an NaNbO₃ phase with incorporated Pb .     

Catalytic properties and surface modification of hexaaluminate microcrystals for combustion catalyst

Spinel oxide (Mn₃0₄) surface layers were produced on hexaaluminate microcrystals by means of the air-oxidation process. The surface layer completely covered the basal plane of hexagonal facets as evident from HREM observation and CO₂ chemisorption measurement. The catalytic activity of as prepared Mn₃0₄/hexaaluminate composites for methane combustion was evaluated as functions of the Mn₃0₄loading and the metal composition of the spinel surface layer. It was revealed that the air oxidationderived composites showed the excellent specific activities superior to those of the corresponding Mn₃0₄/hexaaluminates prepared from the conventional evaporation-to-dryness process. Partial substitution of Fe for Mn of the surface layer was effective in enhancing combustion activity in a whole temperature range.     

Luminescence properties for the high-pressure polymorphs of CaSiO3:Pb2+ and SrSiO3:Pb2+

High-pressure phases of CaSiO₃:Pb²⁺ and SrSiO₃:Pb²⁺ phosphors were synthesized at 40–55 kbar and 1000°C, $\text{viz}$. δ-CaSiO₃:Pb²⁺, δ-SrSiO₃:Pb²⁺, and δ′-SrSiO₃:Pb²⁺, and their luminescence properties were investigated. Among them, δ-CaSiO₃:Pb²⁺ was found to give a strong violet-blue emission ($\text{ca}$. 341 nm) as well as β-CaSiO₃:Pb²⁺ (an atmospheric phase), and the emission intensity of SrSiO₃:Pb²⁺ drastically increased when the host lattice transformed into high-pressure phases (δ and δ′ forms). These results were discussed by considering their structures and quenching temperatures of luminescences.     

Structural integrity evaluation method for overheating rupture of FBR steam generator tube

This paper describes a structural integrity evaluation method for a SG tube of FBR in case of sodium–water reaction and creep rupture tests to obtain the strength of the tube material. In the SG of FBR, if intermediate size of water/steam leak (1–2 kg s⁻¹) would occur from a tube, it could cause overheating rupture of the multiple tubes surrounding the initially failed tube due to generated sodium–water reaction heat. In the ultra-high temperature condition, the creep strength of the material is one of the dominant factors for failure behavior. Accordingly, we tried to apply the creep failure criterion for the overheating rupture of the SG tube. The creep rupture tests have been performed at ultra-high temperature conditions ranging from 1223.2 to 1323.2 K. The test material is ‘Mod .9Cr–1Mo steel’ which is one of the candidate materials for the tubes of the future SG of FBR. The test results have shown that tube rupture depends on the creep strength of the material; hence, instantaneous rupture does not occur even if the stress exceeds the design value of ultimate tensile strength. The test data have been suitably expressed using the Larson–Miller Parameter, and a structural integrity evaluation method based on the sum of the use-fraction associated with the creep damage has been proposed. Based on this method, the structural integrity of the tube in the sodium–water reaction flame has been evaluated. The results show that it is important to detect the initial leak of the tube within a short period and to reduce the steam pressure more rapidly by SG blowdown.     

Interference of an AlGaAs laser diode using a 4.15 km single mode fiber cable

Polarization characteristics in cabled single mode fibers were studied. By using 4.15 km long fibers and a single frequency AlGaAs double-heterostructure laser, interference fringes were observed.