[en] Recent observations and theoretical models of quasars and related objects are reviewed. The three representative theoretical models of the Active Galactic Nuclei (AGN) family of objects are discussed, including the dense cluster model, the supermassive star models, and the model of stellar accretion onto supermassive black holes. The time variability of radio and optical emissions from quasars and other AGNs is considered with reference to Ariel-5 and HEAO-A observations of high energy emissions in the 2-50 keV range. Emphasis is given to recent VLBI data for the compact variable radio sources with multilinear structure. Candidates and techniques for future observations are identified

[en] One of the contributions provided by the Einstein observatory is related to the study of the X-ray point sources in supernova remnants and radio pulsars. The present investigation is concerned with the observing programs which attempt to measure (or set upper limits on) the surface temperature of isolated neutron stars. Particularly important for the involved observations are the Imaging Proportional Counter (IPC) and the High Resolution Imaging Detector (HRI). The results for point source observations (SNR's) are summarized in a table, and the possible significance of the conducted observations is evaluated by comparing them with current theories

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No abstract available

[en] Since the independent suggestions in 1938 of Bethe (1939) and von Weiszaecker (1938) that captures of protons by carbon and nitrogen isotopes were the source of energy generation in stars, the CNO cycles have developed into what might be considered by some a many-cycled monster rivalling the many-headed Hydra. However, those of us who are researchers in nucleosynthesis have found the reactions of the CNO nuclei a fertile field. In this paper the many reactions that may occur are presented. (Auth.)

[en] The point of view expressed in the literature that gravitomagnetism has not yet been observed or measured is not entirely correct. Observations of gravitational phenomena are reviewed in which the gravitomagnetic interaction-a post-Newtonian gravitational force between moving matter-has participated and which has been measured to 1 part in 1000. Gravitomagnetism is shown to be ubiquitous in gravitational phenomena and is a necessary ingredient in the equations of motion, without which the most basic gravitational dynamical effects (including Newtonian gravity) could not be consistently calculated by different inertial observers

[en] If anisotropic post-Newtonian metric potentials exist, celestial bodies will possess anisotropic inertial and/or gravitational masses. The binary pulsar system PSR 1913+16 puts stringent limits on such anisotropies through its observable perihelion precession rate and hence offers a Hughes-Drever-type experiment for massive celestial bodies

[en] Because oxygen has long been recognised as a common carrier gas impurity, several investigations have attempted to characterise its detrimental effects upon analyses by the ECD. Van de Wiel and Tommassen noted in 1972 that severe oxygen contamination of the carrier gas actually increased the response of their instrument to a weakly responding compound, n-butyl bromide. This chapter describes the extension and development of this observation and indicates that O₂-doping can be used to increase ECD response to many compounds. (C.F.)

[en] The author reports a first-principles evaluation of the exchange-correlation potential (V_xc) at a metal surface. An integral equation relating (V_xc) and the non-local electron self-energy (Σ_xc) is solved numerically for a free-electron metal surface, with use of a static approximation for Σ_xc. The strongly-inhomogeneous nature of the electron density profile at the surface is treated exactly, i.e., without invoking the usual local density approximation. The result for V_xc has the correct image-like asymptotic behavior; it derives implicitly from a non-local exchange-correlation energy functional. He studies the effect of non-locality on the position of the effective image plane (z₀) from an analysis of the image tail of V_xc and also from linear-response theory. The difference in the values of z₀ obtained by both method for low metallic densities is attributed to electron overlap effects. He also discusses the effects of V_xc on image-potential induced surface states

[en] This paper presents a study of thermodynamic analysis of the solubility-temperature phase diagrams for solutions of calcium, strontium and barium tungstate in sodium tungstate melts in the temperature range 660 to 1200 ₀C. At temperatures 1000 ₀C and above, the solutions were ideal but below 1000 ₀C the solutions became non-ideal and the non-ideality increased with decreasing temperature. At any mole fraction concentration of the solute the excess free energies of mixing and the activity coefficients increased in the order CaWO⁴ > SrWO⁴ > BaWO⁴, whereas the excess chemical potentials decreased in the order CaWO⁴ < SrWO⁴ < BaWO⁴. (author)