Atlas 5013 tank corrosion test

The type and cause of corrosion in spot welded joints were determined by X-ray and chemical analysis. Fatigue and static tests showed the degree of degradation of mechanical properties. The corrosion inhibiting effectiveness of WD-40 compound and required renewal period by exposing typical joint specimens were examined

Crossover from Fermi Liquid to Non-Fermi Liquid Behavior in a Solvable One-Dimensional Model

We consider a quantum moany-body problem in one-dimension described by a Jastrow type, characterized by an exponent $\lambda$ and a parameter $\gamma$. We show that with increasing $\gamma$, the Fermi Liquid state ($\gamma=0)$ crosses over to non-Fermi liquid states, characterized by effective "temperature".Comment: 8pp. late

A Note on Dressed S-Matrices in Models with Long-Range Interactions

The {\sl dressed} Scattering matrix describing scattering of quasiparticles in various models with long-range interactions is evaluated by means of Korepin's method\upref vek1/. For models with ${1\over\sin^2(r)}$-interactions the S-matrix is found to be a momentum-independent phase, which clearly demonstrates the ideal gas character of the quasiparticles in such models. We then determine S-matrices for some models with ${1\over\sinh^2(r)}$-interaction and find them to be in general nontrivial. For the ${1\over r^2}$-limit of the ${1\over\sinh^2(r)}$-interaction we recover trivial S-matrices, thus exhibiting a crossover from interacting to noninteracting quasiparticles. The relation of the S-matrix to fractional statistics is discussed.Comment: 18 pages, jyTeX (macro included - just TeX the file) BONN-TH-94-13, revised version: analysis of models with 1/sinh^2 interaction adde

Dusty, Radiation Pressure Dominated Photoionization. II. Multi-Wavelength Emission Line Diagnostics for Narrow Line Regions

Seyfert narrow line region (NLR) emission line ratios are remarkably uniform, displaying only ~0.5 dex variation between galaxies, and even less within an individual object. Previous photoionization and shock models of this region were unable to explain this observation without the introduction of arbitrary assumptions or additional parameters. Dusty, radiation pressure dominated photoionization models provide a simple physical mechanism which can reproduce this spectral uniformity between different objects. In the first paper of this series we described this model and its implementation in detail, as well as presenting grids of model emission lines and examining the model structures. Here we explore these models further, demonstrating their ability to reproduce the observed Seyfert line ratios on standard line diagnostic diagrams in both the optical and UV. We also investigate the effects that the variation of metallicity, density and ionizing spectrum have upon both the new paradigm and the standard photoionization models used hitherto. Along with the standard diagnostic diagrams we provide several new diagnostic diagrams in the UV, Optical and IR. These new diagrams can provide further tests of the dusty, radiation pressure photoionization paradigm as well as being used as diagnostics of the metallicity, density and ionizing spectrum of the emission line clouds.Comment: Accepted by ApJS, full pdf including figures can be obtained at http://www.mso.anu.edu.au/~bgroves/Papers/ApJS2.pd

Fusarium pseudograminearum crown rot: growth patterns in planta

Crown rot (causal agent Fusarium pseudograminearum) is a major constraint on wheat production in Australia and globally. While discolouration of tissues is commonly used to screen for resistance, the degree to which the pathogen colonises the full range of seedling and adult host tissues is an important aspect of the disease process. After coleoptile inoculation, seedlings were examined using quantitative PCR to determine the spread of F. pseudograminearum into different host tissues during crown rot pathogenesis at 14 and 28 days after inoculation. Quantitative PCR and visual assessment indicated that while most seedling tissues (leaf sheath, leaf blade, sub-crown internode, primary root and secondary root) were colonised, the basal portion of leaf sheath tissue supported the highest density of F. pseudograminearum. Microscopic assessment demonstrated the growth of hyphae predominantly in the parenchyma cells, with passage into and out of seedling shoot tissues being predominantly via stomata. Assessment of colonised stem tissues in inoculated field trials of adult plants at 16 and 22 weeks after planting indicate a strong correlation between visual discolouration and fungal biomass, with the discolouration occurring in the parenchymatous hypoderm. Hyphae spread from the culm base vertically through the tissues, initially via the hypoderm and the central pith cavity. Colonisation of sclerified cells occurs later in the disease process. Both xylem and phloem tissues became colonised by 16 weeks after planting in all host genotypes tested. Nodal tissues do not appear to constitute any major impediment to the spread of fungal infection. The observation of F. pseudograminearum colonisation of vascular tissues is consistent with the hypothesis of compromised vascular flow of either or both of the xylem and phloem pathways during crown rot disease

Exact Solution of Heisenberg-liquid models with long-range coupling

We present the exact solution of two Heisenberg-liquid models of particles with arbitrary spin $S$ interacting via a hyperbolic long-range potential. In one model the spin-spin coupling has the simple antiferromagnetic Heisenberg exchange form, while for the other model the interaction is of the ferromagnetic Babujian-Takhatajan type. It is found that the Bethe ansatz equations of these models have a similar structure to that of the Babujian-Takhatajan spin chain. We also conjecture the integrability of a third new spin-lattice model with long-range interaction.Comment: 7pages Revte