Violation of the Wiedemann-Franz Law in a Large-N Solution of the t-J Model

We show that the Wiedemann-Franz law, which holds for Landau Fermi liquids, breaks down in a large-n treatment of the t-J model. The calculated ratio of the in-plane thermal and electrical conductivities agrees quantitatively with experiments on the normal state of the electron-doped Pr_{2-x}Ce_xCuO_4 (x = 0.15) cuprate superconductor. The violation of the Wiedemann-Franz law in the uniform phase contrasts with other properties of the phase that are Fermi liquid like.Comment: 4 pages, 2 figures. Typos corrected, one added reference, revised discussion of experiment on 214 cuprate material (x = 0.06

Investigation into the cause of spontaneous emulsification of a free steel droplet : validation of the chemical exchange pathway

Small Fe-based droplets have been heated to a molten phase suspended within a slag medium to replicate a partial environment within the basic oxygen furnace (BOF). The confocal scanning laser microscope (CSLM) has been used as a heating platform to interrogate the effect of impurities and their transfer across the metal/slag interface, on the emulsification of the droplet into the slag medium. The samples were then examined through X-ray computer tomography (XCT) giving the mapping of emulsion dispersion in 3D space, calculating the changing of interfacial area between the two materials, and changes of material volume due to material transfer between metal and slag. Null experiments to rule out thermal gradients being the cause of emulsification have been conducted as well as replication of the previously reported study by Assis et al.[1] which has given insights into the mechanism of emulsification. Finally chemical analysis was conducted to discover the transfer of oxygen to be the cause of emulsification, leading to a new study of a system with undergoing oxygen equilibration

TEM (transmission electron microscopy), APFIM (atom-probe field ion microscopy), and SANS (small-angle neutron scattering) examination of aged duplex stainless steel components from some decommissioned reactors

The present investigation indicates that the primary embrittlement processes of the CF-8 grade cast stainless steel components during extended reactor service are spinodal decomposition of the ferrite phase and M/sub 23/C/sub 6/ carbide precipitation on the austenite-ferrite boundaries. The ferrite hardness measured for the Shippingport reactor valves appears to reflect the different extent of spinodal decomposition among the different valves which contain slightly different Cr contents. G-phase precipitation was minimal compared to that during accelerated aging of CF-8 steel in the laboratory (i.e., near 400/degree/C). This indicates that the activation energy may be strongly influenced by the synergism among the G-phase precipitation, carbide formation, and spinodal decomposition. 13 refs., 2 figs

Registration of Nineteen Waxy Spring Wheats

Nineteen spring waxy (amylose-free) wheat (Triticum aestivum L.) germplasm lines (Reg. no. GP-748 to GP-766, PI 619354–619357, 619359–619363, 619365–619369, 619371–619375) were developed and released by the ARS, USDA, and the Nebraska Agricultural Experiment Station in cooperation with the Agricultural Experiment Stations of North Dakota and Idaho in September 2002. Waxy wheats carry three non-functional (null) alleles (Wx-A1b, Wx-B1b, and Wx-D1b) at the genetic loci encoding the enzyme granule-bound starch synthase (GBSS, EC 2.4.1.21) (Nakamura et al., 1995). GBSS also is known as the “waxy” protein. Waxy wheats produce endospermstarch that is nearly devoid of amylose. Such starch confers unique functional properties to derived wheat flour. Suggested uses for waxy wheats include the production of modified food starches, a blending agent to create flours with optimal amylose concentration for the production of a variety of sheeted and baked food products, and as an animal feed (reviewed by Graybosch, 1998). Waxy wheats also are useful as donors of the Wx null alleles, which may be used to develop partial waxy or reduced-amylose wheats. The presence of one or two such alleles can result in wheat flours with superior performance in certain food applications including white salted noodles (Epstein et al., 2002). Few waxy wheats have been publicly available to date, and those released (Morris and Konzak, 2001) are ill-adapted to North American spring wheat production zones. The release of this set of 19 waxy lines greatly expands the number of available genetic backgrounds carrying the waxy trait in wheat. Pedigrees and Plant Introduction (PI) numbers of the lines are listed in Table 1

Antioxidant intake from diet and supplements and elevated serum C-reactive protein and plasma homocysteine concentrations in US adults: a cross-sectional study

OBJECTIVE: To investigate the association of antioxidant intakes from diet and supplements with elevated blood C-reactive protein (CRP) and homocysteine (Hcy) concentrations. DESIGN: A cross-sectional study. The main exposures were vitamins C and E, carotene, flavonoid and Se intakes from diet and supplements. Elevated blood CRP and Hcy concentrations were the outcome measures. SETTING: The US population and its subgroups. SUBJECTS: We included 8335 US adults aged ≥19 years from the National Health and Nutrition Examination Survey 1999-2002. RESULTS: In this US population, the mean serum CRP concentration was 4·14 (95 % CI 3·91, 4·37) mg/l. Intakes of vitamins C and E and carotene were inversely associated with the probability of having serum CRP concentrations >3 mg/l in multivariate logistic regression models. Flavonoid and Se intakes were not associated with the odds of elevated serum CRP concentrations. The mean plasma Hcy concentration was 8·61 (95 % CI 8·48, 8·74) μmol/l. Intakes of vitamins C, E, carotenes and Se were inversely associated with the odds of plasma Hcy concentrations >13 μmol/l after adjusting for covariates. Flavonoid intake was not associated with the chance of elevated plasma Hcy concentrations. CONCLUSIONS: These results suggest that high antioxidant intake is associated with lower blood concentrations of CRP and Hcy. These inverse associations may be among the potential mechanisms for the beneficial effect of antioxidant intake on CVD risk mediators in observational studies