The effect of hydrogen sulphide on ammonium bisulphite when used as an oxygen scavenger in aqueous solutions

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Adiabatic times for Markov chains and applications

We state and prove a generalized adiabatic theorem for Markov chains and provide examples and applications related to Glauber dynamics of Ising model over Z^d/nZ^d. The theorems derived in this paper describe a type of adiabatic dynamics for l^1(R_+^n) norm preserving, time inhomogeneous Markov transformations, while quantum adiabatic theorems deal with l^2(C^n) norm preserving ones, i.e. gradually changing unitary dynamics in C^n

Tricritical Points in Random Combinatorics: the (2+p)-SAT case

The (2+p)-Satisfiability (SAT) problem interpolates between different classes of complexity theory and is believed to be of basic interest in understanding the onset of typical case complexity in random combinatorics. In this paper, a tricritical point in the phase diagram of the random $2+p$-SAT problem is analytically computed using the replica approach and found to lie in the range $2/5 \le p_0 \le 0.416$. These bounds on $p_0$ are in agreement with previous numerical simulations and rigorous results.Comment: 7 pages, 1 figure, RevTeX, to appear in J.Phys.

Universal low-temperature tricritical point in metallic ferromagnets and ferrimagnets

An earlier theory of the quantum phase transition in metallic ferromagnets is revisited and generalized in three ways. It is shown that the mechanism that leads to a fluctuation-induced first-order transition in metallic ferromagnets with a low Curie temperature is valid, (1) irrespective of whether the magnetic moments are supplied by the conduction electrons or by electrons in another band, (2) for ferromagnets in the XY and Ising universality classes as well as for Heisenberg ferromagnets, and (3) for ferrimagnets as well as for ferromagnets. This vastly expands the class of materials for which a first-order transition at low temperatures is expected, and it explains why strongly anisotropic ferromagnets, such as UGe2, display a first-order transition as well as Heisenberg magnets.Comment: 11pp, 2 fig

The phytosociology and synecology of Tasmanian vegetation with Callitris

Eleven discernible floristic plant communities were identified in vegetatlon containing Callitris in Tasmania. C.rhomboidea and C. oblonga largely segregate into two sets of communities. These sets occupy distinctly different parts of the environmental range of Callitris in Tasmania. Callitris co-occurs with at least 14% of the Tasmanian native higher plant flora in rainforest, wet eucalypt forest, dry eucalypt forest, grassy woodland, scrub and heath, and is dominant in some quadrats of most communities. The major measured correlates of floristic variation in the data set were temperature and precipitation conditions. The combination of the wide ecological range demonstrated by the data set and the highly restricted nature of Callitris distribution suggests that the taxon has a range much diminished by shorterm perturbation. Callitris may have been part of an extensive dry rainforest formation in eastern Tasmania before people invaded the area

Metal-superconductor transition at zero temperature: A case of unusual scaling

An effective field theory is derived for the normal metal-to-superconductor quantum phase transition at T=0. The critical behavior is determined exactly for all dimensions d>2. Although the critical exponents \beta and \nu do not exist, the usual scaling relations, properly reinterpreted, still hold. A complete scaling description of the transition is given, and the physics underlying the unusual critical behavior is discussed. Quenched disorder leads to anomalously strong T_c-fluctuations which are shown to explain the experimentally observed broadening of the transition in low-T_c thin films.Comment: 4 pp., no figs, final version as publishe

The vegetation of Schouten Island, Tasmania

Thirty-seven communities defined by structure and dominance are mapped for Schouten Island which lies within the Freycinet National Park on the east coast of Tasmania. The communities dominated by herbs are mainly coastal in occurrence, those dominated by shrubs are mostly confined to the granitic east of the island, and those dominated by trees are most widespread on the dolerite and sandstone of the west. Thirteen floristic communities are recognized as a result of a monothetic divisive classification of species lists from 160 quadrats. The distribution of these communities, like that of the structure-dominance communities, is most closely related to surface geology and exposure to salt-laden winds. However, their structural expression, and to some extent their distribution, is moulded by other influences such as fire incidence and intensity, topography, and disturbances by man and other animals. Over 450 native higher plant species are recorded for the Freycinet National Park