Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Abstracted in Dissertation abstracts, v. 16 (1956) no. 10, p. 1805-1806. Includes "Conductometric titration of sulfuric and hydrochloric acids and their mixtures in anhydrous acetic acid," by T. Higuchi and C.R. Rehm, reprinted from Analytical chemistry, v. 27 (1955) no. 3, p. 408-411. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Made available in DSpace on 2014-12-02T11:16:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-17Bitstream added on 2014-12-02T11:21:04Z : No. of bitstreams: 1 000775320.pdf: 1787970 bytes, checksum: f55fdff75708b286b90a8cbdd7ba34d9 (MD5) / Foi desenvolvido um equipamento de baixo custo, portátil e multifuncional que integra num único dispositivo quatro técnicas analíticas: fotometria, turbidimetria, nefelometria e fluorimetria. Os principais componentes do equipamento proposto são: diodo emissor de luz (LED) como fontes de radiação; resistor dependente de luz (LDR) como fotodetector; multímetro digital como dispositivo de leitura; um bloco cilíndrico de Nylon preto. Para avaliar o desempenho do equipamento, fez-se a determinação de fósforo (fotometria) e de enxofre (turbidimetria) em fertilizante, de enxofre em material vegetal (nefelometria) e de quinina em água tônica (fluorimetria). As determinações também foram feitas em um equipamento comercial para fins comparativos. Para a determinação de fósforo pelo método do fosfovanadomolibdato, a faixa de trabalho foi de 0,07 a 6,52 mg L-1 (r= 0,9944) e o limite de detecção foi de 0,06 mg L-1. Para a determinação turbidimétrica de sulfato pelo método da precipitação de sulfato de bário, a calibração foi de 2,5 a 100 mg L-1 (r= 0,9982), sendo o limite de detecção 0,23 mg L-1. Na determinação nefelométrica de sulfato, a faixa linear foi de 0,2 a 1,8 mg L-1 (r= 0,9948) e o limite de detecção de 0,10 mg L-1. Na determinação fluorimétrica de quinina, a faixa linear foi de 0,16 a 8,0 mg L-1 (r= 0,9982) e limite de detecção de 0,011 mg L-1. Os resultados obtidos foram comparados com aqueles fornecidos por equipamentos comerciais e resultados concordantes foram observados ao nível de 95% de confiança. Materiais de referência foram analisados pelo equipamento proposto e os resultados para fósforo e enxofre foram concordantes com os respectivos valores certificados ao nível de 95% de confiança. Além do potencial analítico, o equipamento proposto apresenta utilidade como ferramenta didática. O aprendizado do conteúdo de métodos ópticos de análise pode ser estimulado quando há melhor... / A new portable, low cost and multifunctional equipment comprising four analytical techniques (photometry, turbidimetry, nephelometry and fluorimetry) in one single device was developed The main components of the developed device are light emitting diode (LED) as radiation source, light-dependent resistor (LDR) as photodetector, digital multimeter as reading device, and a black plastic container. The performance of the device was checked by determining phosphorus in fertilizer (photometry), sulfur in fertilizer (turbidimetry), sulfur in vegetable samples (nephelometry) and quinine in tonic water (fluorimetry). All determinations were also made in commercial equipments for comparison purposes. The phosphovanadomolibdate method was employed for phosphorus determination within the 0.07 – 6.52 mg L-1 concentration range ((r= 0.9944), and the detection limit was 0.06 mg L-1. The precipitation of barium sulfate was employed for turbidimetric and nephelometric determination of sulfate. For the turbidimetric technique, the calibration range was in the 2.5 - 100 mg L-1 (r= 0.9982), and the detection limit was 0.23 mg L-1. For nephelometry, calibration within 0.2 – 1.8 mg L-1 (r= 0.9948) resulted in detection limit of 0.10 mg L-1. The fluorimetric determination of quinine in the 0.16 – 8.0 mg L-1 linear working range (r= 0.9982) resulted in 0.011 mg L-1 detection limit. Results found by the proposed device were in agreement with those obtained by commercial equipments at 95% confidence level. Standard reference materials were also analyzed, and results for P and S were in agreement with certified values. Besides analytical capabilities, the proposed device may be useful for teaching. The learning goals of some optical techniques may be easier using easy-to-make instruments.

Title: Distribution functions of asteroid physical properties Author: Helena Cibulková Institute: Astronomical Institute of Charles University Supervisor: Mgr. Josef Ďurech, Ph.D., Astronomical Institute of Charles Univer- sity Abstract: In this thesis, I utilize photometric data sparse in time produced by all-sky surveys and investigate physical properties of large asteroid populations. In principle, the individual approach to asteroid modeling cannot compass all objects because new asteroids are continually discovered and we do not have enough data for them. Therefore, in this work I present an essentially different, statistical approach. In a series of papers, we developed two independent methods which use a triaxial-ellipsoid approximation, and we test their applicability and limits. We prove they can be used to the photometric databases like Lowell Observatory database or Pan-STARRS. The output quantities are distributions of the spin axis directions and shape elongations for asteroid populations, and using the Kolmogorov-Smirnov test we search for differences among them. The main result of my work is that the distribution of ecliptical longitudes of spin axes is nonuniform. Moreover, this nonuniformity is more significant for asteroids with low orbital inclinations and the distribution is dependent on...

Understanding the formation and evolution of galaxies is one of the most active areas of research in astrophysics. Hierarchical merging of proto-galactic fragments to build more massive galaxies is the current preferred model. A key prediction of this theory is that haloes of nearby galaxies should contain remnants of this assembly process in the form of tidal debris. Found in all but the smallest of dwarf galaxies, globular clusters (GC) are excellent probes of galaxy haloes. Having high luminosities, they are favourable targets in the outer regions of galaxies where the associated stellar surface brightness is low. GCs are thought to be amongst the oldest stellar systems in the Universe, and are likely born in the most significant phases of galaxy formation. Their metallicities, ages, spatial distributions and kinematics can be used to constrain the assembly history of their host galaxy. In this thesis, I explore the photometric and kinematic properties of several GC systems in our cosmological backyard, the Local Group of galaxies. The work is based on a major spectroscopic campaign, follow-up to the photometric Pan- Andromeda Archaeological Survey (PAndAS), as well as additional optical and near-IR data sets. Radial velocities are obtained for 78 GCs in the halo ofM31, 63 of which had no previous spectroscopic information. The GCs have projected radii between ∼ 20 and 140 kpc, thus sampling the true outer halo of this galaxy. In addition, GCs in the dwarf galaxies NGC 147, NGC 185 and NGC 6822 are also spectroscopically observed. By conducting a detailed kinematic analysis, I find that GCs in the outer halo of M31 exhibit coherent rotation around the minor optical axis, in the same direction as their more centrally located counterparts, but with a smaller amplitude of 86 ± 17 km s−1. There is also evidence that the velocity dispersion of the outer halo GC system decreases as a function of projected radius from theM31 centre, and this relation can be well described by a power lawof index ≈ −0.5. I detect and discuss various velocity correlations amongst GCs that lie on stellar streams in the M31 halo. Simple Monte Carlo tests show that such configurations are unlikely to form by chance, implying that significant fraction of the GCs in the M31 halo have been accreted alongside their parent dwarf galaxies. I also estimate the dynamical mass of M31 within 200 kpc to be (1.2 − 1.6) ± 0.2 × 1012 M⊙. I also characterize the GC systems of three dwarf galaxies in the Local Group: the dwarf elliptical satellites of M31, NGC 147 and NGC 185, and the isolated dwarf irregular NGC 6822. Using uniform optical and near-IR photometry, I constrain the ages and metallicities of their constituent GCs. The metallicities of the GCs around NGC 147 and NGC 185 are found to be metal-poor ([Fe/H]. −1.25 dex), while their ages are more difficult to constrain. The GCs hosted by NGC 6822 are found to be old (>9 Gyr) and to have a spread of metallicities (−1.6 . [Fe/H] . −0.4). I find close similarity between the mean optical (V − I)0 colours of the GCs hosted by these three dwarf galaxies to those located in the M31 outer halo, consistent with the idea that dwarf galaxies akin to them might have contributed toward the assembly of the M31 outer halo GC population. Analysing their kinematics, I find no evidence for systemic rotation in either of these three GC systems. Finally, I use the available GC kinematic data to calculate the dynamical masses of NGC 147, NGC 185 and NGC 6822.

Infrared photometry has been used to determine the physical characteristics of cometary solids. Observations were made of the reflected and thermal parts of the spectra of seven comets. Two of these comets, Bowell and West, were nonperiodic; the other five, Chernyhk, Encke, Kearns-Kwee, Stephan-Oterma, and Tuttle, were periodic. Observations in the 3 μm region of the spectrum of Comet Bowell provide the first direct evidence for the presence of H₂O ice in a comet. This detection represents one of the strongest possible confirmations of Whipple's (1950) icy conglomerate model of cometary nuclei. The observations of the periodic comets have yielded the following picture of the dust in this type of objects: grains with a size distribution ranging from about 0.3 μm to 10 μm, and peaking around a few microns. These grains were made up of at least two components, a silicate material and an absorbing material. These characteristics are remarkably similar to those of the dust in nonperiodic comets. This indicates that the type of dust a comet ejects does not change with age, and supports the absence of large scale differentiation in cometary nuclei. Comet West is the first case of a splitting comet in which the fragments were observed to have differences in their dusty component. These observations suggest that the nucleus of this comet did not have an "onion skin" or layered structure but rather had pockets containing dust grains with different size distributions. Based on the results presented, the relation between cometary and interstellar dust, and the origin of comets are discussed.

We have conducted three surveys to try and locate distant star forming galaxies. The most general survey used deep 2μ images with optical CCD photometry to locate objects with peculiar SEDs. Using the IR data we should be able to locate rapidly star forming galaxies to z = 25. With a 3σ detection limit of 18.5 at K we have found no objects with z > 5 but we have found several blue objects at z < 4 in 16min² of sky. This suggests tha there is no extremely luminous early phase of galaxy formation. We have found several blue objects at z < 4 in 10min² of sky. Of particular interest is an object which has a flat SED from V to K but shows a strong spectral break between B and V and a weaker break at 5800Å. We suggest these may be Lyman limit and Lyman α forest absorption at z-3.8 in a galaxy forming ≈400M(⊙) year⁻¹ of stars. A large sample of galaxies (100 objects) selected to have similar properties (R – I < .5, B – R > 1) has also been found. From this sample it appears this possible high redshift star forming phase only contributes 1/10 of the metal present in disks or spheroids. We have also found 30 Lyman α emission line companions to 12 z = 3 quasars. These objects have Lyman α equivalent widths (50Å) and luminosities (V = 24) consistent with galaxies forming ≈100M(⊙) year⁻¹ of stars. Also, 2 of the quasars have 8 companions and may be in cluster environments. A final survey analyzed optical to IR SEDs of luminous blue radio galaxies at z > 1. In these objects we find SEDs indicative of star formation rates between 10 and 100M(⊙) year⁻¹ but interpretation is difficult due to the AGN component of the sources. While these data seem to suggest a significant star forming phase taking place in galaxies at z ≈ 3-4, interpreting this result is difficult since we cannot determine if we are observing disk or spheroidal populations. In the case of the quasar companions and the radio galaxies, consideration of their dense environments and current epoch morphology suggest that these may be spheroids but these galaxies may not be typical of galaxies in general.

No description available.

Data on the UBV system are presented for 14 quasistellar radio sources, 8 N galaxies,39 radio galaxies and 19 radioquiet galaxies south of +20° declination. Their positions in the two - color diagram show that the integrated colors of the radio galaxies are similar to those of the radioquiet galaxies of the same morphological type. In an absolute radio magnitude - radio index diagram a linear relation exists between M158 and ím158 Boo for radio galaxies of all classes. The QSO:s, however, do not follow this relation, and possible explanations are considered. The brightness and color distributions in the larger galaxies are described in detail. Our results are combined with other data for a discussion of the compositions of these systems. It is suggested that a fairly high amount of reddening occurs in the central regions of several galaxies, as for instance, in NGC 1068 and NGC 1316.

Compact groups of galaxies provide insight into the role of low-mass, dense environments in galaxy evolution because the low velocity dispersions and close proximity of galaxy members result in frequent interactions that take place over extended time-scales. We expand the census of star formation in compact group galaxies by Tzanavaris et al. (2010) and collaborators with Swift UVOT, Spitzer IRAC and MIPS 24 mu m photometry of a sample of 183 galaxies in 46 compact groups. After correcting luminosities for the contribution from old stellar populations, we estimate the dust-unobscured star formation rate (SFRUV) using the UVOT uvw2 photometry. Similarly, we use the MIPS 24 mu m photometry to estimate the component of the SFR that is obscured by dust (SFRIR). We find that galaxies which are MIR-active (MIR-'red'), also have bluer UV colours, higher specific SFRs, and tend to lie in H I-rich groups, while galaxies that are MIR-inactive (MIR-'blue') have redder UV colours, lower specific SFRs, and tend to lie in H I-poor groups. We find the SFRs to be continuously distributed with a peak at about 1 M-circle dot yr(-1), indicating this might be the most common value in compact groups. In contrast, the specific SFR distribution is bimodal, and there is a clear distinction between star-forming and quiescent galaxies. Overall, our results suggest that the specific SFR is the best tracer of gas depletion and galaxy evolution in compact groups.

Call number: LD2668 .T4 1957 G72 / Master of Science