• Design and Synthesis of Imidazolium-Mediated Tröger’s Base-Containing Ionene Polymers for Advanced CO2 Separation Membranes 

  Jason, Bara; Kammakakam, Irshad; O’Harra, Kathryn E.; Jackson, E. (2019-02-15)

  It is highly desirable to integrate the CO_2 solubility benefits of ionic liquids (ILs) in polymeric membrane systems for effective CO_2 separations. Herein, we are exclusively exploring a series of four novel imidazolium-mediated ...
• Synthesis and Performance of 6FDA-Based Polyimide-Ionenes and Composites with Ionic Liquids as Gas Separation Membranes 

  Bara, Jason (2019-07-03)

  Three new isomeric 6FDA-based polyimide-ionenes, with imidazolium moieties andvarying regiochemistry (para-, meta-, and ortho-connectivity), and composites with three differentionic liquids (ILs) have been developed as gas ...
• The Structure and Dynamics of Ringed Galaxies. V. The Kinematics of NGC 1512, NGC 3351, NGC 4725, and NGC 4736 

  Buta, Ronald (1988-03)

  The spirals NGC 1512, NGC 3351, NGC 4725, and NGC 4736 are four large nearby examples of ringed galaxies whose kinematic properties are studied in this paper by means of H-alpha Fabry-Perot interferometry. Velocity fields ...
• The Structure and Dynamics of Ringed Galaxies. IV. Surface Photometry and Kinematics of the Ringed Barred Spiral NGC 6300 

  Buta, Ronald (1987-06)

  NGC 6300 is characterized on the basis of BV photometric plates and VBRI multiple-aperture photoelectric photometry (obtained with the 0.9-m telescope at CTIO) and long-slit image-tube spectra (obtained at the Ritchey-Chretien ...
• Inner Ring Structures in Galaxies as Distance Indicators. III. Distances to 453 Spiral and Lenticular Galaxies 

  Buta, Ronald (1983-01)

  The diameters d_r, of inner ring structures in disk galaxies are used as geometric distance indicators to derive the distances of 453 spiral and lenticular galaxies, mainly in the distance interval 4 < Δ < 63 Mpc. The ...
• An Extragalactic Database. III. Diameter Reduction. 

  Buta, Ronald (1991-03)

  New photometric diameters have been used to study transformation formulae to reduce all visual diameters to a common standard system (isophotal diameter at the limiting surface brightness of 25 B mag arcsec⁻²). A new ...
• The Distance to the Hercules Supercluster. II. Application of Tertiary Indicators and an Estimate of the Hubble Constant 

  Buta, Ronald (1986-10)

  Using data provided in a previous paper, we calculate distances on the zero point of de Vaucouleurs's distance scale to 77 individual galaxies in CGCG field 108, where the core of the Hercules supercluster is found. Three ...
• The Distance to the Hercules Supercluster. I. Basic Data for 220 Galaxies in CGCG Field 108 

  Buta, Ronald (1986-10)

  This paper presents an extensive collection of basic data on revised Hubble types, isophotal diameters, isophotal axis ratios, and integrated magnitudes for 220 galaxies in field 108 of the Catalogue of Galaxies and of ...
• The Structure and Dynamics of Ringed Galaxies. III. Surface Photometry and Kinematics of the Ringed Nonbarred Spiral NGC 7531 

  Buta, Ronald (1987-05)

  The photometric and kinematic properties of the southern galaxy NGC 7531, a large example of a nonbarred spiral possessing a very bright inner ring, are explored via UVBRI surface photometry and emission-line spectroscopy. ...
• The Structure and Dynamics of Ringed Galaxies. II. UBVRI Surface Photometry and H-alpha Kinematics of the Ringed Barred Spiral NGC 1433 

  Buta, Ronald (1986-08)

  The southern galaxy NGC 1433 is one of the nearest examples of a ringed, barred spiral. It is the prototype of revised Hubble type (R')SB(r)ab, and it includes the three main ring types possible in a normal galaxy: a nuclear ...
• The Structure and Dynamics of Ringed Galaxies. I. The Morphology of Galaxy Rings, and Statistics of Their Apparent Shapes, Relative Sizes, and Apparent Orientations with Respect to Bars 

  Buta, Ronald (1986-08)

  The morphologic, metric, photometric, and kinematic properties of ringed galaxies are described. Physical insights which can be gained into all types of rings purely from their morphology and from statistical studies of ...
• Inner Ring Structures in Galaxies as Distance Indicators. II - Calibration of Inner Ring Diameters as Quaternary Indicators 

  Buta, Ronald (1982-02)

  The linear diameters D_r of the inner ring (r) and pseudo-ring (rs) structures in spiral galaxies of different morphological types and stage Sab to Sd (2 ≤ T ≤ 7) in the revised Hubble system are calibrated by means of ...
• Inner Ring Structures in Galaxies as Distance Indicators. I - Dimensionless Systematics of Inner Rings 

  Buta, Ronald (1980-12)

  Inner ring structures are observed in about one quarter of all lenticular or spiral galaxies. Statistics of the relative frequencies of the pure ring (r) and broken ring (rs) varieties in the Second Reference Catalogue ...
• The Nonradial Mode Identification of 53 Persei during Late 1977 and 1978 

  Buta, Ronald (1979-09)

  Various theoretical constraints are imposed on simultaneous light, color, and line profile observations to identify the surface indices of two nonradial modes present in the line profile variable B star 53 Persei during ...
• The Light Variations of Nonradial Pulsators: Theory and Application to the Line Profile Variable 53 Persei 

  Buta, Ronald; M. Smith (1979-08)

  The nonradial pulsator 53 Persei (B4.5 V) has been observed during 13 nights in late 1977 to determine whether its photometric variations are reminiscent of its spectral line profile changes. Inspection of the resulting ...
• The Galactic Extinction towards Maffei 1 

  Buta, Ronald; M. McCall (1983-11-01)

  The extinction of Maffei 1 has been measured by two new techniques. First, BV aperture photometry has been performed to obtain the colour excess from standard aperture-colour relations for early-type galaxies. Secondly, ...
• Bar-induced Perturbation Strengths of the Galaxies in the Ohio State University Bright Galaxy Survey – I 

  Buta, Ronald (2004-12-21)

  Bar-induced perturbation strengths are calculated for a well-defined magnitude-limited sample of 180 spiral galaxies, based on the Ohio State University Bright Galaxy Survey. We use a gravitational torque method, the ratio ...
• Interpretation of the Maximum Light Spectrum of a Type I Supernova 

  Buta, Ronald J.; Falk, S. W.; McCall, M. L.; Sutherland, P. G.; Uomoto, A.; Wheeler, J. C.; Wills, B. J.; Branch, D. (1982-01)

  A high quality optical spectrum of the 1981 Type I supernova in NGC 4536 at maximum light is well represented by a synthetic spectrum consisting of resonance scattering lines of Ca_II, Si_II, S_II, Mg_II, and O_I, superposed ...
• Weakly Barred Early-Type Ringed Galaxies. II. The Double-Ringed S0⁺ Galaxy NGC 7187 

  Buta, Ronald J. (1990-05)

  This paper presents BVR CCD surface photometry of NGC 7187, a southern S0⁺ galaxy possessing an bright circular inner ring and a faint elongated outer ring. The rings both have a contrast comparable to those observed in ...
• A Comparative Study of Morphological Classifications of APM Galaxies 

  Buta, Ronald J. (1995-06-15)

  We investigate the consistency of visual morphological classifications of galaxies by comparing classifications for 831 galaxies from six independent observers. The galaxies were classified on laser print copy images or ...

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