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We study the properties and the origin of the radio emission in the most luminous early-type galaxies (ETGs) in the nearby Universe (MK, Comment: Pre-proofs version - Accepted for publication in A&A

We show that the Schur-Weyl type duality between $gl(1|1)$ and $GL_n$ gives a natural representation-theoretic setting for the relation between reduced and non-reduced Burau representations., Comment: 12 pages. The paper was written in 2010 and published in: Perspectives in analysis, geometry, and topology : On the occasion of the 60th birthday of Oleg Viro; Edi- tors: Ilia Itenberg, Burglind Joricke, Mikael Passare, Birkhauser Verlag GmbH, 2012

The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168 MHz survey of the Northern sky with diverse and ambitious science goals. Many of the scientific objectives of LoTSS rely upon, or are enhanced by, the association or separation of the sometimes incorrectly catalogued radio components into distinct radio sources, and the identification and characterisation of the optical counterparts to these sources. Here we present the source associations and optical and/or IR identifications for sources in the first data release, which are made using a combination of statistical techniques and visual association and identification. We document in detail the colour- and magnitude-dependent likelihood ratio method used for statistical identification as well as the Zooniverse project, called LOFAR Galaxy Zoo, used for the visual classification. We describe the process used to select which of these two different methods is most appropriate for each LoTSS source. The final LoTSS-DR1-IDs value-added catalogue presented contains 318,520 radio sources, of which 231,716 (73%) have optical and/or IR identifications in Pan-STARRS and WISE. The value-added catalogue is available online at https://lofar-surveys.org/, as part of this data release., Comment: 8 figures, 5 tables and 23 pages. This paper is part of the LOFAR surveys data release 1 and has been accepted for publication in a special edition of A&A that will appear in Feb 2019, volume 622. The catalogues and images from the data release will be publicly available at https://lofar-surveys.org/ upon publication in the journal

Human urogenital schistosomiasis caused by Schistosoma haematobium is widely distributed across Africa and is increasingly targeted for control and regional elimination. The development of new high-throughput, cost-effective molecular tools and approaches are needed to monitor and evaluate the impact of control programs on the parasite populations. Microsatellite loci are genetic markers that can be used to investigate how parasite populations change over time and in relation to external influences such as control interventions.Here, 18 existing S. haematobium microsatellite loci were optimised to enable simultaneous amplification across two novel multiplex microsatellite PCR's, each containing nine loci. Methods were developed for the cost effective and rapid processing and microsatellite analysis of S. haematobium larval stages stored on Whatman-FTA cards and proved robust on miracidia and cercariae collected from Zanzibar and Niger.The development of these novel and robust multiplex microsatellite assays, in combination with an improved protocol to elute gDNA from Whatman-FTA fixed schistosome larval stages, enables the high-throughput population genetic analysis of S. haematobium. The molecular resources and protocols described here advance the way researchers can perform multi locus-based population genetic analyses of S. haematobium as part of the evaluation and monitoring of schistosomiasis control programmes.

Vapor-liquid equilibrium data extending to critical pressures are reported for five mixtures of propane with neopentane. The data in pressure, temperature, and density are correlated to high accuracy by the Leung-Griffiths model as modified by Moldover, Rainwater, and coworkers. In addition, a complete bibliography of similar experiments on binary mixtures from the laboratory of W.B.K. is presented. 91 references.

Vapor-liquid equilibrium data ertending to critical pressures are reported for mixtures of propane with each of the hexane isomers, n-hexane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. Dew-bubble curves for five different compositions are tabulated for each of the five mixtures. The data in pressure, temperature, and density are successfully correlated by the Leung-Griffiths model as modified by Moldover, Rainwater, and co-workers. The coexistence surfaces are all quite similar with only subtle differences due to the different shapes of the isomeric hexane molecules

Ontario Geological Survey

Hajjar, R.F., Cherry, R.H. and Kay, W.B., 1986. Critical properties of the vapor—liquid equilibria of the binary system acetone— n -pentane. Fluid Phase Equilibria , 25: 137–146. The P—V—T—x properties for the acetone— n -pentane azeotrope-forming system have been measured by the technique developed by Kay. The experimental uncertainties have been estimated at 0.05 K , 2.4 kPa and 0.06% of the volume. The results for eight different compositions covering the range 180 to 200°C and 2.5 to 4.0 MPa are given. Smoothed critical loci have been plotted. The critical temperatures and pressures were correlated by a quadratic relationship of the form Q cm = Σ i Σ j x i x j Q cij where i , j = 1, 2. The maximum discrepancy in the critical temperature was 0.6 K and in the critical pressure was 0.012 MPa.

The heat capacities of liquid ethanol, toluene, and hexamethyldisiloxane, and of 14 binary mixtures of these were measured at atmospheric pressure at a series of temperatures between 298 and 348 K. In addition, the excess enthalpy was measured for each of the 14 mixtures at room temperature and corrected with the aid of the heat capacities to 298.15 K. The results were represented by empirical equations of a polynomial form. From these equations, the excess heat capacity was derived and the excess enthalpy was calculated, and fitted to equations, as a function of composition at temperatures between 298 and 348 K. All the mixtures are non-ideal as evidenced by the substantial excess enthalpy. The excess enthalpy for the mixtures containing ethanol showed a strong positive temperature dependence, while the variation of temperature between 298 and 348 K had little effect on the excess enthalpy of toluene + hexamethyldisiloxane.

P-V-T-x data for the propane-perfluorocyclobutane system are reported in this paper. The data cover a temperature range from 329.4 to 397.7/degree/K and a pressure range from 60 to 6920 kPa. The low pressure compressibility measurements were used to determine second virial coefficients of pure propane and pure perfluorocyclobutane and for seven of their mixtures. The prediction of second virial coefficients using an extended corresponding states principle is also reported. Excellent predictions of the second virial coefficients of both pure components and mixtures have been obtained using, in the case of mixtures, a binary interaction coefficient obtained from a study of the critical states of the system. 9 refs.

Measurement of vapor-liquid equilibria and azeotropic states of propane-perfluorocyclobutane mixtures are reported. The propane-perfluorocyclobutane system exhibits positive azeotropic behavior which persists in the critical region of the system. The prediction of vapor-liquid equilibria and of the locus of azeotropic points using an extended corresponding states principle is also reported. The predictions require information obtained solely from a study of the critical states of the system. 11 refs.

Vapour-liquid equilibrium relations have been determined at 343.15, 363.15, and 383.15 K for heptamethyltrisiloxane + toluene. The isothermal variation of the total pressure with the composition of the equilibrium liquid and vapor phases was determined experimentally in a recirculating still over the entire composition range. Using Barker's method to calculate the vapour-phase composition, the activity coefficients and excess Gibbs free energy were calculated for each liquid composition. At 343.15 K, the curve of GE against x is asymmetric but as the temperature is increased GE decreases and passes through a minimum point in the heptamethyltrisiloxane-rich region, whereas, in the toluene-rich region, the maximum value of GE decreases and goes through a minimum. The S-shaped curves that are formed indicate an interesting variation in the intramolecular forces of the components with the temperature. Vapour pressures, the normal boiling temperature, liquid densities, and the critical properties are reported for heptamethyltrisiloxane.

Critical-locus curves Tc(x) and Pc(x) have been determined for the carbon dioxide + benzene and sulfur dioxide + benzene systems. The data, together with existing liquid-vapor equilibrium data, are used to construct the complete phase diagrams at high pressures.

The volumetric and phase behavior of propane-perfluorocyclobutane mixtures has been determined in the critical region. This system exhibits a minimum temperature point in its critical locus curve and forms a positive critical azeotrope. The measured critical points in this system and their correlation using an extended corresponding states principle are reported in this paper.

Diagramme PTx de six systemes binaires formes par le methyl-2-pentane, methyl-2-hexane, methyl-2-heptane et le methyl-2-octane

Vapor-liquid equilibria have been measured in the binary systems hexamethyldisiloxane-toluene, hexamethyldisiloxane-ethanol and toluene-ethanol between 333.15 and 358.15 K and the results have been correlated using the Wilson equation. All three binary systems exhibit azeotropic behavior in the temperature range studied.

The critical temperature and pressure and the critical end-point temperature and pressure of n -nonane, n -decane, 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, 1,2,3-trimethylbenzene, and naphthalene were measured with mercury and compared with the critical temperature and pressure of n -nonane, 1,2,4-trimethylbenzene, and naphthalene when measured with gallium. To within the accuracy of the measurements, the values of the critical temperature and pressure obtained with gallium and with mercury were the same. However, the chemical and physical properties of gallium are such as to make it very difficult to devise a procedure that would ensure highly accurate results. Its use as a confining liquid is therefore limited. The differences between the critical temperature and pressure of the pure compounds and critical end-point temperature and pressure of the binary mixtures of mercury + hydrocarbon, ΔT and Δp , respectively, show that the solubility of mercury has a relatively small effect ΔT on the critical temperature, whereas Δp , the partial pressure of mercury, is proportional to, but less than, the vapor pressure of pure mercury. A plot of log 10 ( Δp kPa ) against ( T K ) −1 gives a linear relation which serves as a method of estimating the partial pressure of mercury at a given temperature.

A modified sealed-tube apparatus has been developed for the measurement of the critical temperatures of thermally unstable fluids. The apparatus has been used to measure the critical temperatures of the normal alkanes from n-octane to n-hexadecane. Since the higher alkanes (with more than 10 carbon atoms) decompose at temperatures well below their critical temperatures, a new method of analysis of the apparent critical temperature vs. time data has been developed. This method employs reaction kinetics based on an irreversible first-order reaction and is used to linearize the data and to perform an unambiguous extrapolation to the critical temperature of the undecomposed substance. The method is successful because the temperature history of the substance is recorded by computer, and ampoule contents are analyzed at the completion of the experiment. The critical temperatures of the n-alkanes reported in this paper have been compared with values found in previous studies.

In order to contribute to knowledge of the nature of the phase behavior of partially miscible liquid systems, a study of the benzene-water system was undertaken. The pressures at liquid- and vapor-phase boundaries of fifteen mixtures of benzene and water were determined within the temperature range of 200 to 357°C. Along with a complete numerical tabulation, these data are presented graphically as pressure-temperature, pressure-composition, and temperature-composition phase diagrams to show the nature of the boundaries. Up to the three-phase critical end point, the benzene-water system develops in a manner usually ascribed to a partially miscible system in which the vapor compositin at a point of univariance lies intermediate to the two liquid compositions. The three-phase critical end point occurs at 1,364 1b./sq. in. abs. and 268.3°C., and the composition of the critical phase is 25.8 weight % water, with the remaining liquid phase 92.8 weight % water. The pressure, temperature, and composition of the critical solution end point are deduced as 2,300 1b./sq. in. abs., 306.4°C., and 59 weight % water, respectively. At temperatures between these two critical points the phase behavior is likened to that of a dense gas or fluid dissolved in a liquid. Definite limiting values of temperature and pressure are assignable to this behavior by the extension of the three-phase curve up to the critical solution end point. This extended curve is not a phase boundary, but the temperature and pressure at a given point on the curve represents in a mixture of fixed composition the limit of mutual solubility of the benzene-rich fluid phase and the water-rich phase. At a temperature above or a pressure below the given point the liquid phase begins to vaporize. Above the critical solution end point the vapor-liquid phase boundaries are like those of a normal binary mixture.

Because of the paucity of data on the phase behaviour of mixtures of compounds containing active or polar groups at elevated pressure, the P-V-T-x relations of the iso-butanol-n-butanol, methanol—n-butanol and diethyl ether—n-butanol systems were determined at the liquid-vapour phase boundaries from near their atmospheric boiling points to the highest temperature and pressure at which the liquid and vapour co-exist. In addition, the vapour pressures and saturated liquid and vapour densities of the pure components were determined up to their critical points. The data are presented in the form of tables and graphs. In so far as is indicated by the data, the phase behaviour of binary systems of the alcohols is the same as that exhibited by binary systems of hydrocarbons that belong to a given homologous series.

Because of the paucity of data on the phase behavior of binary systems that form azeotropes, the P-V-T-x relations of the ammonia-isooctane system were determined at the liquid-vapor boundaries from room temperature to the critical temperature of issoctane. Evidence of an azeotrope existing over a very limited pressure and temperature range was obtained. The sistem is unique in that the critical locus contains a minimum temperature point as well as a minimum and a maximum pressure point. These relations are shown to fit a general pattern of phase relations characteristic of binary systems that form azeotropes in the critical region. This pattern serves as an aid for the qualitative prediction of the P-T-x relations of such systems.

The P-V-T-x phase relations of helium—n-butane system were measured in the region of low helium content (up to 10.4 mole % helium). The system exhibits the gas-gas equilibrium originally predicted by Kamerlingh-Onnes and Keesom. The term gas-gas equilibrium is applied because the critical temperatures of the mixtures are higher than the critical temperature of either component. This behavior is quite unlike that observed in most binary systems, in which the critical temperature of the mixtures lie between those of the pure compounds. As a consequence of the shape of the critical locus curve, the system exhibits isothermal retrograde condensation of the second kind.

The vapour-liquid P - V - T - x diagrams of the binary systems composed of methanol, ethanol, n-propanol and n-butanol with benzene as the common component, were determined over a temperature and pressure range which included the critical region. All systems form azeotropes which persist to the critical region except the ethanol-benzene system. The latter becomes nonazeotropic before a critical point is reached. The diagrams confirm the hypothesis proposed earlier, that systems which form azeotropes in the critical region are characterized by a pattern of phase behaviour distinctly different from that for nonazeotropic systems.

A method of calculating the critical properties of binary hydrocarbon systems is presented which is based upon the rigorous thermodynamic equations for the critical point of a binary mixture. By using these equations together with an equation of state, a completely analytical procedure was developed with the aid of a digital computer. The Redlich-Kwong and the Dieterici equations of state were chosen for study. The Redlich-Kwong equation was found superior for predicting critical pressures and temperatures by this method, although the Dieterici equation was better for critical volumes. The two interaction parameters arising from the equation of state were calculated from combining rules or from available experimental critical data on binary systems. To facilitate the latter approach, a mathematical optimization routine was used to find the best values of the interaction parameters for twenty-one binary hydrocarbon systems for which critical data were experimentally determined. The optimum values of the interaction parameters were correlated as functions of the ratio of molecular weights of the components. These correlations enable one to predict quite precisely the critical properties of the binary systems from the pure component data alone.

It is well known that when petroleum fractions of different boiling range are mixed, their volumes are not strictly additive. However, little effort has been made to investigate the effect of composition, chemical nature of the components, and temperature on the magnitude and sign of the deviation from additivity. In order to obtain information on these factors, but to avoid the difficulties attendant with the interpretation of the data on such a complex mixture as petroleum, a study was made of the ternary system, cyclohexane- n -heptane-benzene. Volume changes on mixing were computed from the specific volumes of the pure compounds and their binary and ternary mixtures which were determined experimentally at 60°F and 100°F. An increase in volume on mixing was noted in all mixtures studied, with the value of the maxima at 60°F ranging from about 0·30% in the case of a 60-40 mixture (by weight) of cyclohexane and n -heptane to 0·70% in the case of a 50-50 mixture of cyclohexane and benzene. In the ternary system a maximum of about 0·7% increase in volume was found in mixtures containing equal proportions of cyclohexane and benzene and up to 20 weight % n -heptane. The magnitude of the effect was reduced by an increase in temperature. It was found that the experimental results could be represented satisfactorily by equations based on the theory of regular solutions. The data are of interest in connection with the manufacture of certain petroleum products that are prepared by the blending of different fractions.

Since the present theories of the atom indicate that an electron is attracted by the atom nucleus, they also suggest that the principal difficulty in accomplishing the addition of an electron is in obtaining such (unknown) conditions as make the attraction effective. Electrons with a velocity corresponding to 138,000 to 145,000 volts were caused to strike the surface of liquid mercury. The mercury served as an anti-cathode in an x-ray tube. (This work was done before the electron tube of Coolidge was available.) When the experiments were begun it was not expected that positive results would be attained, since either the voltage may be too low, or the number of electrons shot into the surface (4\ifmmode\times\else\texttimes\fi{}${10}^{21}$) too small, but it was thought to be of value to show this to be true. The addition of an electron to the nucleus of an atom of mercury should give an atom of gold. Since no gold was found in the exceedingly sensitive tests used, it is shown that either less than one in a billion of the electrons attached itself to an atom nucleus, or else all or a part of the nuclei produced were not sufficiently stable to endure for the period (24 to 48 hours) of the tests.

The second virial coefficients of pure n-butane and of two mixtures of helium and n-butane were determined in the range 100° to 225°C. from isothermal compressibility measurements. Values of B11 (pure n-butane) agree closely with those of McGlashan and Potter (11) at low temperatures and of Hirschfelder et al. (7) at higher temperatures. Values of the mixed second virial coefficient B12 were computed from the mixture data. B12 shows little variation with temperature over this interval. The interpretation of the data as the behavior of a mixture composed of hard sphere (helium) in a real gas (n-butane) is discussed.

Critical states of the five binary systems of n-hexane, 2-methylpenthane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane with propane as the common component have been measured and are presented in this paper. A simple method based on the concept of excess (critical) properties has been used to correlate the data. The excess critical temperature and the excess critical pressure of all five systems attain a maximum value at approximately the same composition of propane, indicating that the position of the maxima in these curves may be a function solely of the size (and not shape) of the pure components. 6 refs.