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Secondary structure in three tRNA's as studied by D2O and cyclodextrin perturbation of their ultraviolet spectraHoffman, Jerald Lee, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
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The Photo-Chemical Reactions of IsopentaneWalker, Russell C. 08 1900 (has links)
This thesis describes an experiment in the ultraviolet absorption of hydrocarbons.
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The ultraviolet absorption spectra of lignin and related compoundsGlading, Ralph E. January 1940 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1940. / Includes bibliographical references (leaves 44-45).
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The Infrared and Ultraviolet Spectra of PropynalMoule, David 10 1900 (has links)
The infrar-red spectra of gaseous HC=CCHO, DC=CCHO, HC=CCDO and the Raman spectrum of liquid HC=CCHO has been measured and analysed to give the normal vibrational frequencies of the molecule in the electronic ground state. The electronic band spectrum of propynal with origin at 4144 A has been photographed under low resolution in both emission and absorption and analysed in terms of the vibrational frequencies associated with the combining electronic states. The origin band for both HC=CCHO and DC=CCHO has been photographed under high resolution and a partial rotational analysis is presented for this band. The transition responsible for the electronic spectrum has been identified as being of n ->3pi*, 3A"<- 1A' type, and the observed spectrum confirms the theoretical predictions as to the structure that results from a transition of this type. / Thesis / Doctor of Philosophy (PhD)
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The transmission characteristics of some optical crystals in the extreme ultravioletMcClinton, Arthur Thomas 16 February 2010 (has links)
The transmissions of some optical crystals were determined for the vacuum ultraviolet using a SeyaNamioka monochromator. The characteristic low wavelength cutoffs were determined for crystals transmitting in the region 1050-2000 A. The crystals so studied are: MgF₂, NaF, LaF₃, SrF₂, BaF₂, BeO, Al₂O₃, KD*P, KDP, ADP, NaCl, NdF₃, KBr, CdF₃ and PrF₃. The techniques employed in the experiment and the data obtained will be presented. / Master of Science
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Interactions of sodium ethacrynate in intravenous admixture with selected cardiovascular and psychotherapeutic agentsCatania, Patrick N. 01 January 1970 (has links)
The possibility of drug incompatibilities is a matter of serious concern when administering two or more therapeutic agents. This is especially true in the case of parenteral administration when one must be aware not only of therapeutic interactions but also chemical and physical reactions that might occur.
In order to avoid incompatibilities, drug manufacturers have suggested that parenteral solutions be used immediately after reconstitution and that admixtures of parenteral products not be administered wherever possible (1,2). Physicians have also stressed the importance in avoiding multiple drug therapy (3,4). In spite of these suggestions, the practice of multiple drug therapy is prevalent.
Because of this, there has been an increase in awareness of the number of drug admixtures administered in the hospital. At the University of Michigan Hospital over two thirds of the intravenous fluids administered contained two or more therapeutic agents (5). Holysko and Ravin (6) report that 48% of the intravenous fluids contain one additive, 30% contain two additives, and 22% contain three or more additives. The survey taken by Patterson and Nordstrom (7) showed that 24% of the solutions administered intravenously contained two drugs 1 and that 16% of the intravenous solutions contained three or more additives.
The increased awareness of the problems in admixtures of parenterals has contributed to the increased use of centralized intravenous additive programs at various hospitals. The hospital pharmacist is now becoming more responsible for the preparation of intravenous admixtures (8). The need for additional information concerning potential interactions when admixtures of therapeutic agents for intravenous use are administered is evident. The lack of information includes, in addition to incompatibilities, areas of interest such as stability, sterility, and clinical effectiveness (8,9).
This report will discuss a method to detect potential chemical interactions. The drugs under investigation are sodium ethacrynate (Edecrina) in combination with selected cardiovascular and psychotherapeutic agents when in admixture in normal saline solution. Possible therapeutic interactions and physical incompatibilities of these combinations will also be discussed.
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Wavelength-selective ultraviolet (Mg,Zn)O photodiodes: Tuning of parallel composition gradients with oxygen pressureZhang, Zhipeng, von Wenckstern, Holger, Lenzner, Jörg, Grundmann, Marius 07 August 2018 (has links)
We report on ultraviolet photodiodes with integrated optical filter based on the wurtzite (Mg,Zn)O
thin films. Tuning of the bandgap of filter and active layers was realized by employing a
continuous composition spread approach relying on the ablation of a single segmented target in
pulsed-laser deposition. Filter and active layers of the device were deposited on opposite sides of a
sapphire substrate with nearly parallel compositional gradients. Ensure that for each sample position
the bandgap of the filter layer blocking the high energy radiation is higher than that of the
active layer. Different oxygen pressures during the two depositions runs. The absorption edge is
tuned over 360 meV and the spectral bandwidth of photodiodes is typically 100 meV and as low as
50 meV.
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Mapping Ultra-Low Surface Brightness H-alpha Emission Around Nearby GalaxiesMelso, Nicole January 2021 (has links)
The circumgalactic medium (CGM) is thought to contain the massive reservoir of gas exchanged over the course of galactic evolution, including the fuel for future star formation and the remnants of a galaxy’s merger history. Models and observations suggest that the CGM has a very low density, and faint optical or UV emission from this gas is exceedingly difficult to detect. This thesis is a combination of simulations, instrumentation and observations aimed at ultimately understanding the distribution and kinematics of ionized gas in the CGM.
We present a suite of small-box hydrodynamic simulations created to study the interaction between smooth gas inflow and supernovae-driven outflow at the disk-halo interface where the galactic disk transitions into the CGM. They track the fate and kinematic evolution of gas accreting onto the galactic disk and find evidence of partial mixing with the enriched outflow. We use equilibrium photoionization models to create mock surface brightness maps of Ha and OVI emission. These observables motivate the need for new instrumentation and in suit, we present the newly commissioned Circumgalactic Ha Spectrograph (CHaS): a custom integral field unit (IFU) spectrograph tailored to detect low-surface brightness optical emission in the low-redshift universe. CHaS is deployed in the focal plane of the MDM Observatory Hiltner 2.4-meter telescope, conducting wide-field (10' x 10') spectral imaging with a competitive survey speed proportional to the high instrument grasp. A microlens array segments the field of view into > 60,000 spectra with a spatial resolution of 2.6'' and a resolving power of R ~ 10,000.
Accordingly, CHaS is capable of resolving structure on scales less than 1 kpc (at 10 Mpc) and distinguishing emission lines separated by less than 40 km/s. As designed, a 50-100h exposure with CHaS would be the deepest H-alpha image and velocity field ever obtained, reaching a surface brightness of a few mR on scales of a few arcmin. Shorter, hour-long integrations with CHaS reveal a detailed map of the denser interstellar medium and bright emission at the disk-halo interface. We present results for three early commissioning targets: NGC 4631, NGC 7331 and NGC 1068, including high-resolution velocity maps and detections of new extended emission line regions far into the halo. We report a previously unnoted ribbon of ionized gas around NGC 1068, extending tens of kpc from the galactic disk beyond the known outer filamentary structure. Ongoing observations will provide a deeper probe of ionized gas far into the CGM of many nearby galaxy targets, detecting faint extended emission and mapping the velocity of ionized gas beyond the disk.
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Avaliação do desempenho de embalagens para alimentos quando submetidas a tratamento por radiação ionizanteMOURA, ESPERIDIANA A.B. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:50Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Avaliação do desempenho de embalagens para alimentos quando submetidas a tratamento por radiação ionizanteMOURA, ESPERIDIANA A.B. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:50Z (GMT). No. of bitstreams: 0 / No presente trabalho foram estudadas as propriedades mecâncias (resistência à tração e porcentagem de alongamento na ruptura e resistência à perfuração), propriedades ópticas, permeabilidade ao gás oxigênio e ao vapor d\'água, migração total em simulante aquoso (ácido acético 3%) e gorduroso (n- heptano), e a formação de produtos voláteis da radiólise, com vistas à avaliar o efeito da radiação ionizante (raios gama e feixe de elétrons) em filmes flexíveis mono e multicamadas comerciais, fabricados no Brasil para a indústria de produtos cárneos. Os filmes estudados foram: um monocamada de polietileno de baixa densidade (LDPE) e um multicamadas coextrusado composto de polietileno de baixa densidade (LDPE), copolímero de etileno e álcool vinílico (EVOH) e poliamida (PA), ou seja, a estrutura: LDPE/EVOH/PA. As irradiações foram realizadas em uma fonte de 60Co do tipo Gammacell e em um acelerador de elétrons do tipo eletrostático (l,5MeV), com doses de até 30 kGy, na temperatura ambiente e presença de ar. As alterações nas propriedades foram avaliadas de acordo com a dose de radiação aplicada, oito dias após a irradiação e novamente, dois a três meses após a irradiação. Os resultados mostraram que as reações de cisão predominaram sobre as reações de reticulação para ambos os filmes estudados, irradiados com raios gama ou com feixe de elétrons. As variações observadas em função da irradiação, nas propriedades avaliadas não limitam a aplicação final desses filmes, uma vez que não ultrapassaram o limite de segurança especificado pelo fabricante em nenhuma dose e período em que foram estudadas. Concluiu-se que os filmes estudados podem ser utilizados, sob o ponto de vista das propriedades avaliadas, como embalagens para produtos pasteurizáveis por radiação e radioesterilizáveis usando irradiadores gama ou aceleradores de elétrons, nas doses de radiação estudadas. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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