Debye mass from domainwalls and dimensionally reduced phase diagram

To measure the Debye mass in dimensionally reduced QCD for $N_c\le 3$ we replace in the correlator of two Polyakov loops one of the loops by a wall triggered by a dimensionally reduced twist. The phase diagram for $N_c=3$ has R-parity broken in part of the Higgs phase.Comment: LATTICE98(hightemp

The role of iron on the degradation and mineralization or organic compounds using conventional Fenton and photo-Fenton processes

The role of iron on the degradation of different organic compounds, differing in their structure (aliphatic versus aromatic) and iron complex formation capacity, by conventional and photo-Fenton processes was investigated. Results show that these chemical characteristics can affect the degree of treatment in terms of COD and TOC removals. While aromatics exhibited a fast and great reduction in the COD by the conventional Fenton process, aliphatic compounds, apart from acetic acid, required the presence of UV light to enhance treatment results. EDTA and oxalic acid responded very positively to UV irradiation in both COD removal and mineralization, reaching the highest values showed by aromatics; and results depended on the intensity of the UV light applied. Phenol and 4-nitrophenol responded favourably to UV irradiation in terms of mineralization and slightly in COD removal. Reductions in the COD were almost total (95.99%), while only an 80% of reduction in the TOC was achieved, for the best photo-Fenton treatment of oxalic acid, phenol and nitrophenol. 60% COD and 40% TOC removals were achieved correspondingly in the case of EDTA. Acetic acid showed almost no mineralization and low COD removal (≈20%) when treated by a conventional Fenton process; and did not enhanced results when assisting the treatment with UV light. Photo-regeneration of ferrous ion and photo-decarboxylation of iron carboxylates are assessed in the framework of these results

Electrochemical Processes for In-situ Treatment of Contaminated Soils

Soils at typical DOE (Department of Energy) waste sites are known to be contaminated by a host of hazardous organic chemicals, heavy metals and radionuclides. Typical hazardous organic contaminants include chlorinated solvents such as trichloroethylene (TCE), tetrachloroethylene (PCE), chloroform, and carbon tetrachloride, and polycyclic aromatic hydrocarbons (PAHs) such as naphthalene, fluorene, phenanthrene, anthracene and pyrene. It is also known that major toxic heavy metals such as Pb, Cr, As, Zn, Cu, Hg, and Cd and major radionuclides such as Tritium, U, Sr90, Pu, Cs137, and Tc are also commonly present at some DOE waste sites. Some of these chemicals are relatively mobile and can migrate down to the vadose zone and/or the aquifer region

Fuzzy Sphere Dynamics and Non-Abelian DBI in Curved Backgrounds

We consider the non-Abelian action for the dynamics of $N Dp'$-branes in the background of $M Dp$-branes, which parameterises a fuzzy sphere using the SU(2) algebra. We find that the curved background leads to collapsing solutions for the fuzzy sphere except when we have $D0$ branes in the $D6$ background, which is a realisation of the gravitational Myers effect. Furthermore we find the equations of motion in the Abelian and non-Abelian theories are identical in the large $N$ limit. By picking a specific ansatz we find that we can incorporate angular momentum into the action, although this imposes restriction upon the dimensionality of the background solutions. We also consider the case of non-Abelian non-BPS branes, and examine the resultant dynamics using world-volume symmetry transformations. We find that the fuzzy sphere always collapses but the solutions are sensitive to the combination of the two conserved charges and we can find expanding solutions with turning points. We go on to consider the coincident $NS$5-brane background, and again construct the non-Abelian theory for both BPS and non-BPS branes. In the latter case we must use symmetry arguments to find additional conserved charges on the world-volumes to solve the equations of motion. We find that in the Non-BPS case there is a turning solution for specific regions of the tachyon and radion fields. Finally we investigate the more general dynamics of fuzzy $\mathbb{S}^{2k}$ in the $Dp$-brane background, and find collapsing solutions in all cases.Comment: 49 pages, 3 figures, Latex; Version to appear in JHE

Impacts of potential future sea level rise on the North branch of the Changjiang river estuary: Quantifying the saline water intrusion in the dry season

The phenomenon of global sea level rise (SLR) is undeniable; the 4th IPCC report summaries that the\ud average rise rate of global is 1.8 mm/y since 1961. It is widely taken for granted that SLR will have a severe impact on\ud saline water intrusion processes in estuarine areas. In this paper, by using a two-dimensional hydrodynamic model\ud (MIKE21) and SLR scenarios of 0.5m, 1m and 2m, the impacts of potential future SLR on the North Branch of the\ud Changjiang River Estuary are evaluated by quantifying salinity changes in the dry season. The field data of tidal levels,\ud flow velocities and salinities are employed to validate the model, and the computed results match the observed values\ud well, which indicates that the validated model can provide reliable performances in reproducing the hydrodynamic and\ud saline water intrusion processes in the Changjiang River Estuary, then this validated numerical model was run with\ud present sea level as well as 0.5m, 1m and 2 m SLR scenarios in the dry season respectively. The computations show\ud that: i)the amplification of tidal levels in the upper reach of the South Branch is greater than that in the upper reach of\ud the North Branch with SLR; ii)the ebb and flood discharges in the upper cross-section of the North Branch both respond\ud to SLR with a significant increase trend, with the ebb flow split ratio of the North Branch increasing from 3.8% to\ud 10.3% in 2m SLR scenario; iii)the salinity in the North Branch presents a decrease trend with SLR, and the decreasing\ud extent in the upper reach is 11.4%-33.4%, which is obvious greater than that in the middle and lower reaches.\ud Consequently, it can be concluded that SLR enhances the ebb hydrodynamics and alleviates the saline water intrusion in\ud the North Branch

Tracing Ghost Cavities with Low Frequency Radio Observations

We present X-ray and multi-frequency radio observations of the central radio sources in several X-ray cavity systems. We show that targeted radio observations are key to determining if the lobes are being actively fed by the central AGN. Low frequency observations provide a unique way to study both the lifecycle of the central radio source as well as its energy input into the ICM over several outburst episodes.Comment: 6 pages, 4 figures, To appear in the Proceedings of "Heating vs. Cooling in Galaxies and Clusters of Galaxies", eds. H. Boehringer, P. Schuecker, G. W. Pratt & A. Finoguenov (ESO Astrophysics Symposia, Springer-Verlag), Garching (Germany), August 200

Brane-Antibrane Systems at Finite Temperature and Phase Transition near the Hagedorn Temperature

In order to study the thermodynamic properties of brane-antibrane systems, we compute the finite temperature effective potential of tachyon T in this system on the basis of boundary string field theory. At low temperature, the minimum of the potential shifts towards T=0 as the temperature increases. In the D9-antiD9 case, the sign of the coefficient of |T|^2 term of the potential changes slightly below the Hagedorn temperature. This means that a phase transition occurs near the Hagedorn temperature. On the other hand, the coefficient is kept negative in the Dp-antiDp case with p <= 8, and thus a phase transition does not occur. This leads us to the conclusion that only a D9-antiD9 pair and no other (lower dimensional) brane-antibrane pairs are created near the Hagedorn temperature. We also discuss a phase transition in NS9B-antiNS9B case as a model of the Hagedorn transition of closed strings.Comment: 28 pages, 3 figures, minor errors correcte

Geometrical Tachyon Kinks and NS5 Branes

We further investigate the $NS$5 ring background using the tachyon map. Mapping the radion fields to the rolling tachyon helps to explain the motion of a probe $Dp$-brane in this background. It turns out that the radion field becomes tachyonic when the brane is confined to one dimensional motion inside the ring. We find explicit solutions for the geometrical tachyon field that describe stable kink solutions which are similar to those of the open string tachyon. Interestingly in the case of the geometric tachyon, the dynamics is controlled by a cosine potential. In addition, we couple a constant electric field to the probe-brane, but find that the only stable kink solutions occur when there is zero electric field or a critical field value. We also investigate the behaviour of Non-BPS branes in this background, and find that the end state of any probe brane is that of tachyonic matter 'trapped' around the interior of the ring. We conclude by considering compactification of the ring solution in one of the transverse directions.Comment: Latex, 24 pages, 1 eps fig; clarifying comments added to Section 2; typos correcte

Electrified Fuzzy Spheres and Funnels in Curved Backgrounds

We use the non-Abelian DBI action to study the dynamics of $N$ coincident $Dp$-branes in an arbitrary curved background, with the presence of a homogenous world-volume electric field. The solutions are natural extensions of those without electric fields, and imply that the spheres will collapse toward zero size. We then go on to consider the $D1-D3$ intersection in a curved background and find various dualities and automorphisms of the general equations of motion. It is possible to map the dynamical equation of motion to the static one via Wick rotation, however the additional spatial dependence of the metric prevents this mapping from being invertible. Instead we find that a double Wick rotation leaves the static equation invariant. This is very different from the behaviour in Minkowski space. We go on to construct the most general static fuzzy funnel solutions for an arbitrary metric either by solving the static equations of motion, or by finding configurations which minimise the energy. As a consistency check we construct the Abelian $D3$-brane world-volume theory in the same generic background and find solutions consistent with energy minimisation. In the $NS$5-brane background we find time dependent solutions to the equations of motion, representing a time dependent fuzzy funnel. These solutions match those obtained from the $D$-string picture to leading order suggesting that the action in the large $N$ limit does not need corrections. We conclude by generalising our solutions to higher dimensional fuzzy funnels.Comment: 38 pages, Latex; references adde

Application of antagonistic rhizobacteria for control of Fusarium seedling blight and basal rot of lily

Three antagonistic bacteria, Streptomyces misionensis strain PMS101, Bacillus thermoglucosidasius strain PMB207, and S. sioyaensis strain PMS502, were tested for sensitivity to the foliar fungicide Sporgon (a.i. 50% prochloraz-Mn complex) and for efficacy in controlling Fusarium diseases of lily. Results showed that the growth of all three antagonistic strains of bacteria was completely suppressed by Sporgon at a concentration of 500 mu g/mL, but B. thermoglucosidasius strain PMB207 and S. misionensis strain PMS101 were unaffected at concentrations of 100 mu g/mL or lower. A large-scale trial in an automated and environment-controlled commercial greenhouse showed that treatment of scale bulblets of lily with Sporgon (100 mu g /mL) and B. thermoglucosidasius strain PMB207 (1-1.2 x 10(7) cfu/mL) or 100 mu g/mL Sporgon and S. misionensis strain PMS101 (1-1.4 x 10(7) cfu/mL) resulted in a significant reduction (P 0.05). Results of the greenhouse and field experiments showed that treatment of scale bulblets or one-year-old bulbs of lily with B. thermoglucosidasius strain PMB207 (1-1.2 x 10(8) cfu/mL) or S. misionensis strain PMS101 (1-1.4 x 10(8) cfu/mL) without Sporgon was also effective in the control of basal rot caused by F. oxysporum f. sp. lilii. These studies reveal that B. thermoglucosidasius strain PMB207 and S. misionensis strain PMS101 are biocontrol agents which have potential for use in the commercial production of lily bulbs, as they can be used alone or in combination with the fungicide Sporgon at low concentration (< 100 mu g/mL)