Oscillations in radioactive exponential decay

Several older and recent reports provided evidence for the oscillatory character of the exponential decay law in radioactive decay and attempted to explain it with basic physics. We show here that the measured effects observed in some of the cases, namely in the decay of 226Ra, 32Si in equilibrium, and 36Cl, can be explained with the temperature variations

Petrophysical evaluation and uncertainty analysis of Roseneath and Murteree shales reservoirs in Cooper Basin, Australia (a case study)

This study investigates petrophysical characteristics of lacustrine Permian Murteree and Roseneath shales in relation to reservoir evaluation of the most prospective gas shale plays in the Cooper Basin, Australia. Both shales were investigated for gas volumes by employing unconventional petrophysical techniques through a combination of source rock parameters acquired by geochemical analysis, and integrating the extracted parameters into log interpretation and core studies. Modeling mineralogical composition using wireline logs require the selection of a proper mineral model. In this study, the mineral model was built in the Interactive Petrophysics (IP's) Mineral Solver module by integrating all regional sedimentological, petrographic, SEM (Scanning electronic microscope), pulse decay and X-ray diffraction data (XRD) from core and chip cutting samples. This study developed a mineral grouping framework to assist in the selection of a proper model to easily solve complex shale gas reservoirs for gas volumes. Furthermore, the permeability of both shales depends on in-situ confining stress and permeability of these cores and can be calculated through decay rate of a pressure pulse applied to experimental data. Subsequent to the integrated study as explained above, it is concluded on the basis of extruded parameters (shale porosity, permeability, volume of kerogen, volume of brittle minerals and water saturation) that Murteree formation exhibits better potential than Roseneath formation in and around Nappameri, Patchawarra and Tenappera troughs, while poor potential is exhibited in the Allunga trough. The only location where Roseneath exhibits better potential is in Encounter-01 well

BcB_c Spectroscopy from Lattice QCD

We present first results for $B_c$ spectroscopy using Lattice Non-Relativistic QCD (NRQCD). For the NRQCD action the leading order spin-dependent and next to leading order spin-independent interactions have been included with tadpole-improved coefficients. We use multi-exponential fits to multiple correlation functions to extract ground and excited $S$ states and give accurate values for the $S$ state hyperfine splitting and the P state ($B^{**}_c$) fine structure, including the effects of $^1P_1/^3P_1$ mixing.Comment: 12 pages uuencoded latex file + 1 postscript figur

Lithological and facies analysis of the Roseneath and Murteree shales, Cooper Basin, Australia

Unconventional shale plays have received marked attention over the last five years because of their economic potential for hydrocarbon generation, and yet they are amongst the least understood of all clastic sedimentary rock systems. The Cooper Basin is one of the largest Gondwana intracratonic basins in Australia, extending from northern South Australia into south-western Queensland and covering approximately 130,000 km2. The basin is may be prospective for shale gas, particularly within the lacustrine shales of the Permian Murteree and Roseneath formations. This study investigates lithological characteristics of these two units in relation to reservoir evaluation. Core samples representing the Dirkala-02 and Moomba-46 wells were used for petrographic analysis. A combination of wireline log analysis, thin section petrography, X-ray diffraction and pyrolysis analysis was used to define and characterize four distinct lithofacies facies within the Roseneath and Murteree shales: siliceous mudstone, organic siliceous mudstone, calcareous siliceous mudstone, and silty siliceous mudstone. The siliceous mudstone and organic siliceous mudstone are the most common. Diagenetic siderite occurs in all four lithofacies. A conceptual depositional model is developed for deposition of the Roseneath and Murteree shales. Wireline-log cross plots were interpreted and utilized in the construction of electrofacies. The study was concentrated on the northern portion of the basin between the Nappameri and Patchawarra Troughs in order to understand the nature of lithofacies and variability in reservoir architecture, which was controlled by relative lake level fluctuation. The results of this study will aid in the evaluation of shale gas potential for this portion of the basin, as well as a better understanding of shale gas opportunities in the Cooper Basin more generally

Nanostructure and paramagnetic centres in diamond-like carbon: Effect of Ar dilution in PECVD process

Diamond-like carbon (DLC) films were deposited utilising plasma enhanced chemical vapour deposition (PECVD) with acetylene precursor, diluted with 0 – 45% argon. Electron paramagnetic resonance (EPR) measurements show the presence of one paramagnetic centre with no change in spin population over the range of film deposition conditions. However, the EPR linewidth decreases with increasing argon content of the precursor mix, suggesting an enhancement of motional narrowing due to an increase in electron delocalization, related to an increase in the sp2 cluster size. Atomic force microscopy (AFM) measurements indicate the surface of the DLC is formed of nanoscale asperities of material. With radii of tens of nanometres for films deposited with zero argon, the size of the features increases with the argon dilution of the acetylene. Energy dispersive x-ray analysis and electrical measurements further elucidate the changes in film structure

Kinetics of substrate oxidation and hydrogen peroxide production by Mycoplasma mycoides subsp. mycoides Large Colony (LC) type and Mycoplasma mycoides subsp. capri

Mycoplasma mycoides subsp. mycoides Large Colony (LC) type is a pathogen of goats causing contagious agalactia and respiratory disease, found on all continents where small ruminants are kept. It shares close genetic characteristics with M. mycoides subsp. capri. Substrate oxidation by 22 strains of M. mycoides subsp. mycoides LC from nine countries was compared with that of eight strains of M. mycoides subsp. capri from five countries. There was considerable similarity in the substrates used, but substrate saturation coefficients (Ks) varied for different substrates. Substrate utilization patterns and Ks values did not (1) significantly differentiate the LC strains from each other, (2) show any correlation with geographical origin, or (3) distinguish the LC strains from the capri strains. These results support previous studies justifying the reclassification of these subspecies as a single species

Methodology for exposure and risk assessment in complex environmental pollution situations

Frequently environmental pollution results from different hazardous substances released in the environment, meaning that contaminated sites may have many different chemical sources and transport pathways. Problems concerning environmental pollution affect mainly physical, chemical and biological properties of air, water and soil. The relationships between the sources, exposure and effects of contaminants to human and ecological receptors are complex and many times are specific to a particular site, to certain environmental conditions and to a particular receptor. Often the methodology for exposure and risk assessment to environmental pollution is translated into sets of assessment questions. These questions are used to meet the needs of assessment, particular important in focusing the assessment during the problem formulation. Risk assessments vary widely in scope and application. Some look at single risks in a range of exposure scenarios, others are site-specific and look at the range of risks posed by a facility. In general, risk assessments are carried out to examine the effects of an agent on humans (Health Risk Assessment) and ecosystems (Ecological Risk Assessment). Environmental Risk Assessment (ERA) is the examination of risks resulting from technology that threaten ecosystems, animals and people. It includes human health risk assessments, ecological risk assessments and specific industrial applications of risk assessment that analyze identified end-points in people, biota or ecosystems

Photodisintegration of Ultra-High-Energy Cosmic Rays revisited

Recent microscopic and phenomenological calculations of giant dipole resonances for A <= 56 nuclei are presented. The derived photodisintegration cross sections are exhaustively compared to the photonuclear data available to date. An accurate description of the data is found. Our new calculations are also compared with the previous and widely-used estimates of Puget, Stecker and Bredekamp. The present calculations also include all the possible paths down the nuclear chart. The impact on the photodisintegration of ultra-high-energy cosmic rays (UHECR) is illustrated for a Fe source with typical energies of 10^{20-21} eV. At energies around 10^20 eV, the new cross sections are found to modify the UHECR photodisintegration rates. At energies around 10^21 eV, it is recommended to solve a full reaction network to estimate the photodisintegration rate of the UHECR.Comment: 16 pages, 8 figures, accepted for publication in Astroparticle Physic

Exposure of polychlorinated naphthalenes (PCNs) to Pakistani populations via non-dietary sources from neglected e-waste hubs:A problem of high health concern

To date limited information's are available concerning unintentional productions, screening, profiling, and health risks of polychlorinated naphthalenes (PCNs) in ambient environment and occupational environment. Literature reveals that dust is a neglected environmental matrix never measured for PCNs. To our knowledge, this is the first study to investigate the concentrations and health risks of PCNs in indoor dust, air, and blood of major e-waste recycling hubs in Pakistan. Indoor air (n = 125), dust (n = 250), and serum (n = 250) samples were collected from five major e-waste hubs and their vicinity to measure 39 PCN congeners using GC-ECNI-MS. ∑ 39PCN concentrations in indoor air, dust, and serum (worker > resident > children) samples ranged from 7.0 to 9583 pg/m 3, from 0.25 to 697 ng/g, and from 0.15 to 401 pg/g lipid weight, respectively. Predominant PCN congeners in indoor air and dust were tri- and tetra-CNs, while tetra- and penta-CNs were dominant in human serum samples. The higher PCNs contribution was recorded at the recycling units, while the lower was observed at the shops of the major e-waste hubs. Higher contribution of combustion origin CNs in air, dust and human samples showed combustion sources at the major e-waste hubs, while Halowax and Aroclor based technical mixture showed minor contribution in these samples. Mean toxic equivalent (TEQ) concentrations of PCNs were 2.79E +00 pg-TEQ/m 3, 1.60E −02 ng-TEQ/g, 8.11E −01 pg-TEQ/g, 7.14E −01 pg-TEQ/g, and 6.37E −01 pg-TEQ/g for indoor air, dust, and serum samples from workers, residents, and children, respectively. In our study, CNs- 66/67 and −73 in indoor air, dust, and human serum were the great contributors to total TEQ concentrations of PCNs. This first base line data directs government and agencies to implement rules, regulation to avoid negative health outcomes and suggests further awareness in regard of provision of proper knowledge to the target population. Due to lack of data on production, screening, and profiling of PCNs, this is the first study to investigate concentrations of PCNs in indoor dust, air, and blood serum at the major e-waste recycling hubs in Pakistan where crude recycling methods were common and the potential health risks to human via its non-dietary pathways exposure would experience. This study results identified that Tri-to penta-CNs were dominant in the environmental samples and showed that higher PCNs contribution in the environmental samples was recorded by Combustion based activities as compared to technical mixture based CNs

Semiclassical relativistic strings in S^5 and long coherent operators in N=4 SYM theory

We consider the low energy effective action corresponding to the 1-loop, planar, dilatation operator in the scalar sector of N=4 SU(N) SYM theory. For a general class of non-holomorphic ``long'' operators, of bare dimension L>>1, it is a sigma model action with 8-dimensional target space and agrees with a limit of the phase-space string sigma model action describing generic fast-moving strings in the S^5 part of AdS_5 x S^5. The limit of the string action is taken in a way that allows for a systematic expansion to higher orders in the effective coupling $\lambda/L^2$. This extends previous work on rigid rotating strings in S^5 (dual to operators in the SU(3) sector of the dilatation operator) to the case when string oscillations or pulsations in S^5 are allowed. We establish a map between the profile of the leading order string solution and the structure of the corresponding coherent, ``locally BPS'', SYM scalar operator. As an application, we explicitly determine the form of the non-holomorphic operators dual to the pulsating strings. Using action--angle variables, we also directly compute the energy of pulsating solutions, simplifying previous treatments.Comment: LaTeX, 50 pages, 1 figure. v2: References added, minor corrections. 54 pages. v3: Few changes. One paragraph added at the end of section 3. 55 page