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The uv and ir absorption spectra of thirty-one 2-thiophenesulfomides have been investigated. The uv spectroscopic data are discussed in relation to the absorption of some parent compounds and the spectral changes are correlated with substituent effects. The ir stretching frequencies of NH bond are reported. In KBr discs, only one NH stretching absorption band, due to associated sulfonamide, is observed. In CCl 4 solutions, however, two bands, due to free and associated NH group, are present. A good correlation is found between the Hammett substituent constants and the NH frequencies. Also, the ir stretching of SO, CS and SN bonds is briefly discussed.

The Coulomb interaction is used to calculate energy shifts and mixing amplitudes ofJ=3/2−,T=1/2 and 3/2 states in9B and9Be. For the 14.39 MeV level in9Be, a neutron width of 0.15 keV is calculated from theT=1/2 admixtures in the wave function.

The effect of water on the low-frequency (102-105 Hz) complex permittivitv of native, sold-state collagen has been investigated experimentally. Measurements at ambient temperature show that dry collagen exhibits essentially no frequency or temperature dependence. As water is absorbed, both dielectric constant and loss factor increase simultaneously and rise sharply upward at a hydration level which may be associated with the completion of the primary absorption layer as determined from independent water absorption studies. The behaviour is qualitatively identical to that observed for other proteins and related materials. Temperature-dependent measurements made under vacuum conditions in the range −196°C to +100°C are characteristic of the dielectric properties of the water in the sample. Dehydration produced by successive temperature recycling to the maximum temperature effectively eliminates any temperature or frequency dependence. A maximum in the temperature-dependent curves is found at about +40°C and is explained as the superposition of two processes: (1) the transition of water molecules from bound to free states, and (2) the difffusion of water molecules out of the system. The dielectric constant of dry collagen, after desorption at ambient temperature, is about 4.5. Desorption at elevated temperatures reduced the room temperature value to about 2.3 and the liquid nitrogen temperature value to a number indistinguishable from the optical value of n2 = 2.16.

The excitation curves of the reactions 55 Mn(p, γ) 56 Fe and 55 Mn(p, n) 55 Fe in the energy range from 1300 to 1850 keV show eight asymmetrical resonances with fine structures. The resonances have been interpreted as isobaric analogue resonances corresponding to the low-lying states of 56 Mn 1 ) and have been compared with results of (d, p) experiments 2 ). The shapes of corresponding resonances of the (p, γ) and (p, n) reaction were different in some cases, and they were fitted with a formula given by Robson 3 ).

1. An Tierversuchen werden bei Bleivergiftung der Serumeisenspiegel, das Bluteisen und die Hamatokritwerte verfolgt.

Excitation energies and electromagnetic form factors of the low-lying positive-parity states have been calculated in 9 Be and 13 C on the basis of a particle-core coupling model. The results are compared with recent electron scattering experiments and photon data. The first excited levels in the two nuclei show a large contribution from the spin term of the electromagnetic interaction at low-momentum transfer q 2 −2 .

The resonance process in muonic bismuth has been calculated using a microscopic particle-core coupling model. The results are in good agreement with available experimental data.

In the excitation curve of the reactions 55 Mn(p,γ) 56 Fe and 55 Mn(p,n) 55 Fe 8 isobaric analog resonances in the compound-nucleus 56 Fe have been observed, corresponding to the low-lying levels of 56 Mn. The Coulomb displacement energy for the ground-states of the pair 56 Mn 56 Fe is observed as 8.59 ± 0.01 MeV.

Evidence is found for a magnetic polarization effect in muonic 205Tl and 209Bi atoms by the observation of a change in hindred M1 transition rates.

Orientador: Hans Georg Richter Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal Área de concentração: Tecnologia e utilização de produtos florestais A secagem, é considerada lima das fases mais importantes em uma indústria madeireira. A introdução de métodos artificiais, quando dentro de normas técnicas1 corretas, tem beneficiado o setor, com uma maior flexibilidade ao mercado, obtenção de materiais de melhor qualidade, redução dos custos, proteção eficaz da madeira e obtenção de teores de umidade desejados. O presente estudo consta de um levanta mento e análise das condições da secagem artificial para madeira serradas, nos Estados do Paraná e Santa Catarina, considerados até a atualidade como centro da produção madeireira ' do Brasil. A introdução de estufas convencionais, deu-se a cerca de 20 anos, com um aumento acentuado do potencial instalado nos últimos 2 anos, o qual supre apenas uma pequena parcela das necessidades. Os principais problemas encontrados são relacionados: 1. Baixa qualidade do equipamento 2. Inexistência de programa de secagem 3. Baixo nível técnico dos operadores 4. Pouca atenção dispensada pela administração à fase de secagem 5. Inexistência de cálculos de custos relacionados a operação secagem 6. Falta de critérios na escolha do equipamento adequado. Em conseqüência, as perdas por defeitos na secagem assumem alta importância, bem como a desuniformidade obtida no teor de umidade final, contribui para a diminuição dos lucros da empresa. Atitudes deveriam ser tomadas, a curto espaço de tempo, através de órgãos governamentais, associações de classe, e da própria indústria, afim de: 1. Elaborar cursos de secagem para operadores 2. Obter programas tecnicamente elaborados 3. Incutir modificações nos equipamentos atualmente empregados 4. Incentivar pesquisas, publicações relativas á secagem artificial. Drying is one of the most important steps, during conversion of the raw material wood into pro ducts in practically all sectors of wood industry. The introduction of artificial drying' methods when applied correctly, has brought great economic and technical advantages to wood industry with regard to meeting higher quality requirements of more flexible markets, cost reduction, efficient wood protection and controlled moisture contents suitable for further industrialization of the raw material. The present, study consists of a survey and analysis of artificial drying conditions of sawn wood in two states of southern Brazil, Parana and Santa Catarina. The first conventional kilns were introduced in this area about 20 years ago and, although installed capacity has increased substantially in the last two years, it meets only a small percentage (13%) of the overall' needs for wood drying. Drying installations and techniques en countered during the survey have been found Seriously deficient with regard to the following sectors. 1. low quality of equipment (kilns) 2. lack of proper drying schedules 3. education and technical knowledge of kiln operates is inadequate 4. of all phases during wood processing the drying sector is paid the least attention by industry administration 5. lack of cost calculations for drying operation. 6. absence of technical and economical criteria with regard to the choice of adequate drying equipments. Consequently losses due to defects caused by inadequate drying and considerable variation of . the final moisture content are quite common .and tend to reduce considerably company profits. In view of these facts which badly prejudice the profitability of wood industry it is urgently recommended that industry itself, professional association and government immediately. 1. organization of short time wood drying courses for kiln operators 2. elaboration drying schedules for 1 wood species groups of high economical importance 3. provide for modifications and improvements of. drying equipment actually in use 4. propagate, finance research and publications with respect to adequate application of artificial drying techniques and equipment.

The dc conductivity of hydrated bovine Achilles' tendon collagen has been determined as a function of hydration over a limited temperature range. At ambient temperature the conductivity changes from 10−15 (Ω cm)−1 in the dry state to about 10−8 (Ω cm)−1 at ∼24% water content by weight. For all temperatures the conductivity increases exponentially with hydration obeying σ(h) = A exp (βh), where h is a measure of the hydration, A is independent of temperature, and the parameter β ∼ T−1. It is shown that the data may be described by an impurity-type mechanism in which the effective activation energy for the process is dependent on temperature and hydration. Conduction is assumed to be electronic with the impurity (water) acting as a donor. In the solid state the effect of water on the conductivity is reversible indicating the absence of chemical alteration of the hydrated collagen.