The primary objective of this study was to obtain nano-emulsion containing polyphenolic compounds extracted from sour cherry pomace and to investigate the effect of degritting of polyphenolic concentrates on the encapsulation efficiency and particle size distribution of capsules and emulsions. It was also aimed to study storage and baking stability of the capsules. Extracted polyphenolic concentrate was degritted at 10,000 rpm for 2 min. Purification reduced Sauter mean diameter (D[32]) of concentrated extract from 5.76 &mu / m to 0.41 &mu / m. Unpurified and purified concentrates were freeze dried for 48 h to obtain extracted phenolic powder (EPP) and purified extracted phenolic powder (PEPP), respectively. Powders were entrapped in two types of coating materials which contain 10% maltodextrin (MD) or 8% MD-2% gum arabic (GA). Samples were prepared by ultrasonication (160 W, 50% pulse) for 20 min. Emulsions containing EPP had D[32] of 1.65 and 1.61 &mu / m when they were entrapped in 10% MD and 8% MD-2% GA coating material solutions, respectively. It was possible to obtain nano-emulsions when purification step was performed. Emulsions prepared with PEPP and coated with 10% MD and 8% MD-2% GA had D[32] of 0.396 and 0.334 &mu / m, respectively. Encapsulation efficiency of the capsules increased significantly from 86.07-88.45% to 98.01-98.29% by means of degritting (p&le / 0.001). Loss of total phenolic content during storage at 43% and 85% relative humidities was smaller for encapsulated powders when compared to powders not entrapped in coating material. In addition, encapsulation significantly increased retention of phenolic compounds from 15.1-22.2% to 30.4-30.7% during baking (p&le / 0.05).

Sour cherry (Prunus cerasus L. (sin. Cerasus vulgaris Mill., Prunus vulgaris Schur)) is widely grown stonefruit tree in Lithuania. Productivity of sour cherry orchard depends on many tightly related factors. It's know that negative temperature and spring frosts are important factors determinating plant productivity. These factors must be considered in plant breeding. Risks of extreme temperatures, humidity deficiency and spring frosts increases due to climate change. Plant reaction to climate change depends on plant species, cultivar and on biotic or abiotic factors. Spring starts earlier and suddenly during past years, thus vegetation of cherries starts earlier. However, probability of plant damage to spring frosts increases due to earlier vegetation, because plants are susceptible to negative temperatures due to loss of the predictive and consequential (secondary) dormancy. The aim of the research was to evaluate DNA polymorphism of sour cherry cultivars with different resistance to spring frosts, to characterize nature of phenological phase changes, to evaluate biochemical characteristics of sour cherry resistance to spring frosts formation by analysis of changes in carbohydrate amount and composition in generative organs and fruit ovaries at different phenological phases, and to evaluate changes in gene expression levels of galactinol synthase and raffinose synthase during flower development. It was established, that specific rhythm of phenological development is... [to full text] / Paprastoji vyšnia (Prunus cerasus L. (sin. Cerasus vulgaris Mill., Prunus vulgaris Schur)) yra plačiai auginamas kaulavaisinis augalas Lietuvoje. Vyšnių sodo produktyvumas priklauso nuo daugelio tarpusavyje susijusių veiksnių. Oro temperatūra yra vienas svarbiausių vyšnių paplitimą ir jų derlių lemiantis veiksnys. Žinoma, kad neigiamos temperatūros ir pavasario šalnos yra svarbus veiksnys, į kurį reikia atsižvelgti vykdant augalų selekciją. Keičiantis klimatui, didėja ekstremalių temperatūrų ir drėgmės deficito pavojus bei pavasario šalnų rizika (Augspurger, 2013). Augalų reakcija į klimato kaitos pokyčius priklauso nuo augalo rūšies ir veislės bei abiotinių ir biotinių veiksnių. Pastaraisiais metais pavasaris ateina greičiau ir staigiai. Tai paveikia vyšnias – jų vegetacija prasideda anksčiau. Anksti pradėjus vegetuoti išauga tikimybė, kad augalus pažeis pavasario šalnos. Lietuvoje nuostolių padaro vėlyvos pavasario šalnos, kurių metu pažeidžiami žiedai ir vaisių užuomazgos. Tuo metu augalai jau būna išėję iš būtinosios ir priverstinės ramybės ir jautrūs neigiamoms temperatūroms. Tyrimų tikslas buvo įvertinti skirtingo atsparumo šalnoms vyšnios veislių DNR polimorfizmą, fenologinių tarpsnių kaitos pobūdį, atskleisti paprastosios vyšnios atsparumo pavasario šalnoms formavimosi biochemines ypatybes ištiriant bendro angliavandenių kiekio ir jų sudėties kitimą skirtinguose fenologiniuose tarpsniuose esančių augalų generatyviniuose organuose ir vaisių užuomazgose, nustatyti... [toliau žr. visą tekstą]

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Butter and milk fat from different composition and quality raw, peculiarities of production technology, and influence for butter in join-stock “ Kauno pienas” Laura Lazdauskienė, GT fakultetas VI kurso studentė Mokslinio darbo vadovas dr.Doc.Kazimieras Pauliukas Introduction A main problem of join-stock is production realization. The company purpose – to extend products assortment and reform their quality, likewise to improve process of technology. Methods. Work accomplished join-stock Company “ Kauno pienas”. Milk was investigated in chemical and microbiology laboratories. The date about milk composition and quality were compared with enterprise “ Pieno tyrimai “. The main indicators of milk quality ( fat, proteins, lactose) a milk quality indicators ( somatic cell count, total bacterial contamination ) have influence for butter production. Results and discussion. At most, influences for butter production have fats, which vary in milk. The fat amount in milk is major in wintertime, in summer time is lesser. Influence for amount fats has triglyceride in milk. During wintertime, their amount increase and fat amount in milk likewise increase. The consistence of make butter in wintertime is solid and grain, in summertime – soft. Given a major fat amount in milk, less remain in skinny milk. Somatic cell count and total bacterial contamination has influence for butter quality. This indicator was compared with average of republic. It was noticed, that this indicator during five... [to full text]

Swallowing impairment or dysphagia can be a consequence of several neurological and anatomical disorders such as stroke, Parkinson’s diseases, and head and neck cancer. Management of patients with dysphagia often involves diet modification, sensory stimulation, and exercise programme with the primary goal being safe swallowing to maintain nutrition. The aim of this project was to evaluate the effects of lemon odour and tastant on swallowing behaviour in healthy young adults. Specifically, the neural excitability and biomechanical characteristics of swallowing were measured in two studies. Neural excitability was evaluated by measuring motor-evoked potentials (MEPs) from the submental muscles which were evoked by transcranial magnetic stimulation (TMS) of the motor cortex. Biomechanical characteristics were evaluated through measures of submental muscle contraction, pressure changes in the oral cavity and pharynx, and the dynamics of the upper oesophageal sphincter (UES). Two groups of volunteers (16 in each group) participated in two separate studies. In the MEP study, 25% and 100% concentrations of lemon concentrate were presented separately as olfactory and gustatory stimuli. The four stimuli were randomly presented in four separate sessions. The olfactory stimulus was nebulized and presented via nasal cannula. Filter paper strips impregnated with the lemon concentrate placed on the tongue served as the gustatory stimulus. Tap water was used as control. TMS-evoked MEPs were measured at baseline, during control condition, during stimulation, immediately poststimulation, and at 30-, 60-, and 90-min poststimulation. Experiments were repeated using the combination of odour and tastant concentration that most significantly influenced the MEP. The biomechanical study used (a) surface electromyography (sEMG) to record contraction of the submental muscles, (b) lingual array with pressure transducers to record glossopalatal pressures, and (c) pharyngeal manometry to record pressures in the pharynx and the UES. Similar methods of presenting the stimuli were used to randomly present the 25% and 100% concentrations of lemon odour and tastant. All data were recorded concurrently during stimulation. The concentration of odour and tastant that produced the largest submental sEMG amplitude was selected for presentation of combined stimulation. Data were then recorded during combined stimulation and at 30-, 60-, and 90-min poststimulation. Results from the MEP study showed increased MEP amplitude at 30-, 60-, and 90-min poststimulation during swallowing compared to baseline, but only for the combined stimulation. Poststimulation results from the biomechanical study showed decreased middle glossopalatal pressure at 30 min and decreased anterior and middle glossopalatal contact duration at 60 min. No poststimulation changes were found in sEMG and pharyngeal manometry measures. During combined odour and tastant stimulation, there were increased pressure and contact duration at the anterior glossopalatal contact and decreased hypopharyngeal pressure. Generally, these changes correspond to increased efficiency of swallowing. In conclusion, these are the first studies to have measured the effects of flavour on neural excitability and biomechanics of swallowing and the first to have shown changes in MEP and several biomechanical characteristics of swallowing following flavour stimulation. These changes were present poststimulation, suggesting mechanisms of neural plasticity that may underlie potential value in the rehabilitation of patients with dysphagia.

The aim of the research. To evaluate the genetic diversity in sweet and sour cher-ry populations, to characterize the injuries to blossoms and fruits caused by blossom blight brown rot, to identify the species composition of Monilinia patho-gens and to analyse the DNA polymorphism within and among pathogens popula-tions. Main tasks: 1. To analyse the genetic diversity of sweet and sour cherry cultivars and wild cherry population, growing in west Lithuania, using molecular marker methods (AFLP and SSR). 2. To determine factors affecting injuries caused by blossom blight. 3. To investigate characteristics of brown rot agent M. fructigena development in sweet and sour cherry cultivars differing in resistance to brown rot. 4. To identify species composition of Monilinia spp. in IH LRCAF stone fruit collection based on PCR methood and to evaluate inter- and intraspecific DNA polymorphism of Monilinia spp. based on AFLP method. / Tyrimų tikslas. Įvertinti trešnės ir paprastosios vyšnios populiacijų ge-netinę įvairovę, ištirti trešnės ir paprastosios vyšnios žiedų bei vaisių užsikrėtimo kaulavaisinių monilioze mechanizmus, nustatyti šios ligos sukėlėjų Monilinia rūšinę sudėtį bei išanalizuoti jų tarprūšinį ir vidurūšinį DNR polimorfizmą. Tyrimų uždaviniai: 1. Išanalizuoti skirtingų pagal atsparumą moniliozinei degligei LAMMC SDI kaulavaisinių kolekcijoje augančių trešnės ir vyšnios veislių ir Vakarų Lietuvo-je augančios laukinės trešnės populiacijos genetinę įvairovę, naudojant molekuli-nius metodus (SSR ir PFIP) bei palyginti PFIP pradmenų kombinacijų informaty-vumo rodiklius. 2. Nustatyti žiedų pažeidimo moniliozine deglige (M. laxa) veiksnius: ištirti žiedo da¬lių atsparumą moniliozinei degligei, nustatyti kuriame žiedo raidos tarpsnyje jie yra jautriausi, įvertinti, ar kuokelių mechaninis pašalinimas (kastravimas) turi įtakos užsikrėtimui moniliozine deglige ir nustatyti ar žiedų ap-dulkinimas gali aktyvuoti augalo imunines reakci¬jas ir užkirsti kelią patogenui patekti į žiedo vidų. 3. Ištirti rudojo puvinio sukėlėjo M. fructigena vystymosi ypatumus kontrastinėse pa¬gal atsparumą rudajam puviniui trešnės ir vyšnios veislėse. Nusta-tyti, ar vaisiai jautresni patogenui yra nokimo pradžioje ar techninės brandos (skynimo) metu, įvertinti vaisių mechani¬nio pažeidimo poveikį užsikrėtimui ruduo-ju puviniu. 4. Identifikuoti Monilinia spp. LAMMC SDI kaulavaisinių kolekcijos augyne rūšinę sudėtį PGR... [toliau žr. visą tekstą]

It had been shown that the transport properties of CMS membranes varies as a function of H₂S exposure making the conditioning protocol an important step in identifying the steady state properties of CMS membranes. In this study the conditioning of CMS membranes with H₂S was studied for the determination of the acid gas steady state transport properties. The conditioned steady state has been shown to be the same state for both an extended conditioning protocol using high pressure mixed gas and a rapid conditioning protocol using pure H₂S. The rate of conditioning does vary between the two conditioning protocols as the rapid conditioning protocol takes 48 hours less to reach the conditioned steady state. The results of this study also show that oxygen doping during the formation of the CMS membrane affects the final, conditioned steady state transport properties.

Orientador: Luiz de Souza Corrêa / Banca: Aparecida Conceição Boliani / Banca: Silvia Correa Santos / Resumo: O maracujazeiro por ser uma trepadeira necessita de suporte para seu desenvolvimento e produção, sendo que este pode afetar a qualidade, produção, bem como custos. Desta forma, o presente trabalho teve como objetivo avaliar o efeito de diferentes sistemas de condução sobre o crescimento, produção e qualidade dos frutos de maracujazeiro amarelo, bem como o custo de implantação das espaldeira utilizadas. O experimento foi conduzido na Fazenda Experimental, pertencente à Agência Paulista de Tecnologia dos Agronegócios, localizada no Município de Andradina-SP, em um Latossolo Vermelho, de abril 2006 a fevereiro de 2007. Foram utilizados os seguintes tratamentos: T1- Espaldeira Vertical com 1 fio arame e 1 cordão; T2- Espaldeira Vertical com 1 fio arame e 2 cordões (um para cada lado a 2,0 m); T3-Espaldeira Vertical com 2 fios arame e 2 cordões (1 para cada lado a 2,0 m); T4- Espaldeira Vertical com 2 fios arame e 2 cordões (só para um lado a 1,6 e 2,0m); T5- Espaldeira Vertical com 2 fios arame e 4 cordões (2 para cada lado); T6- Espaldeira em T com 2 fios de arame e 2 cordões (só para um lado a 2,0 m) e T7- Espaldeira em T com 2 fios de arame e 4 cordões (2 para cada lado), adotando-se o delineamento em blocos casualizados e três repetições. Em função dos resultados pode-se concluir que: a) O sistema de condução em espaldeira em T, com 2 fios de arame e 4 cordões, foi o que proporcionou maior número de ramos e maior produtividade de frutos; b) Houve superioridade na produção na espaldeira em T, não havendo diferenças nas espaldeiras verticais com um e dois fios de arame; c) O aumento do número de cordões promoveu o aumento da emissão de ramos produtivos, número de frutos colhidos e massa por hectare; d) As caracteristicas tecnológicas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The passionfruit plant for being a semiligneous climbing plant needs support for its development and production, what can affect its, quality, production as well as its cost. Thus, the present work had as objective to evaluate the effects of different systems of conduction on the growth, production and quality of the yellow passionfruit plant fruits as well as the implementation cost of the Espalier used. The experiment was set up on the Experimental farm, which belongs to the Agência Paulista de Tecnologia dos Agronegócios, located in the Andradina county-SP in a red Latossol, april of 2006 even February of 2007. The following treatments were used : T1-Vertical Espalier with 1 wire and 1 string; T2- Vertical Espalier with 1 wire and 2 strings (one for each side at 2,0 m); T3-Vertical Espalier with 2 wires and 2 strings (1 for each side at 2,0 m); T4- Vertical Espalier with 2 wires and 2 strings (only for one side at 1,6 and 2,0m); T5- Vertical Espalier with 2 wires and 4 strings (2 for each side); T6- Espalier in T with 2 wires and 2 strings (for only one side at 2,0 m) and T7- Espalier in T with 2 wires and 4 strings (2 for each side),adopting the random block design and 3 repetitions. According to the results, it's possible to conclude that: a) The system of conduction in espalier in T, with 2 wires and 4 strings, was the one which provided the greatest number of branches and production of fruits per area; b) There was greater production in espalier in T, without any difference in the Vertical Espaliers with one or two wires; c) The increase in the number of strings promoted the increase on the growth of productive branches, number of fruit picked and mass per hectare; d) The technological characteristics were not influenced by the conduction system; e) The system of conduction of Espalier in T with 2 wires and 4 strings demosntrated better economic viability in relation to the other. / Mestre

Made available in DSpace on 2014-06-11T19:29:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-29Bitstream added on 2014-06-13T20:39:23Z : No. of bitstreams: 1 komuro_lk_me_ilha.pdf: 626052 bytes, checksum: 03cb2f9c533d084d6bdfde30c94057d7 (MD5) / O maracujazeiro por ser uma trepadeira necessita de suporte para seu desenvolvimento e produção, sendo que este pode afetar a qualidade, produção, bem como custos. Desta forma, o presente trabalho teve como objetivo avaliar o efeito de diferentes sistemas de condução sobre o crescimento, produção e qualidade dos frutos de maracujazeiro amarelo, bem como o custo de implantação das espaldeira utilizadas. O experimento foi conduzido na Fazenda Experimental, pertencente à Agência Paulista de Tecnologia dos Agronegócios, localizada no Município de Andradina-SP, em um Latossolo Vermelho, de abril 2006 a fevereiro de 2007. Foram utilizados os seguintes tratamentos: T1- Espaldeira Vertical com 1 fio arame e 1 cordão; T2- Espaldeira Vertical com 1 fio arame e 2 cordões (um para cada lado a 2,0 m); T3-Espaldeira Vertical com 2 fios arame e 2 cordões (1 para cada lado a 2,0 m); T4- Espaldeira Vertical com 2 fios arame e 2 cordões (só para um lado a 1,6 e 2,0m); T5- Espaldeira Vertical com 2 fios arame e 4 cordões (2 para cada lado); T6- Espaldeira em T com 2 fios de arame e 2 cordões (só para um lado a 2,0 m) e T7- Espaldeira em T com 2 fios de arame e 4 cordões (2 para cada lado), adotando-se o delineamento em blocos casualizados e três repetições. Em função dos resultados pode-se concluir que: a) O sistema de condução em espaldeira em T, com 2 fios de arame e 4 cordões, foi o que proporcionou maior número de ramos e maior produtividade de frutos; b) Houve superioridade na produção na espaldeira em T, não havendo diferenças nas espaldeiras verticais com um e dois fios de arame; c) O aumento do número de cordões promoveu o aumento da emissão de ramos produtivos, número de frutos colhidos e massa por hectare; d) As caracteristicas tecnológicas... / The passionfruit plant for being a semiligneous climbing plant needs support for its development and production, what can affect its, quality, production as well as its cost. Thus, the present work had as objective to evaluate the effects of different systems of conduction on the growth, production and quality of the yellow passionfruit plant fruits as well as the implementation cost of the Espalier used. The experiment was set up on the Experimental farm, which belongs to the Agência Paulista de Tecnologia dos Agronegócios, located in the Andradina county-SP in a red Latossol, april of 2006 even February of 2007. The following treatments were used : T1-Vertical Espalier with 1 wire and 1 string; T2- Vertical Espalier with 1 wire and 2 strings (one for each side at 2,0 m); T3-Vertical Espalier with 2 wires and 2 strings (1 for each side at 2,0 m); T4- Vertical Espalier with 2 wires and 2 strings (only for one side at 1,6 and 2,0m); T5- Vertical Espalier with 2 wires and 4 strings (2 for each side); T6- Espalier in T with 2 wires and 2 strings (for only one side at 2,0 m) and T7- Espalier in T with 2 wires and 4 strings (2 for each side),adopting the random block design and 3 repetitions. According to the results, it’s possible to conclude that: a) The system of conduction in espalier in T, with 2 wires and 4 strings, was the one which provided the greatest number of branches and production of fruits per area; b) There was greater production in espalier in T, without any difference in the Vertical Espaliers with one or two wires; c) The increase in the number of strings promoted the increase on the growth of productive branches, number of fruit picked and mass per hectare; d) The technological characteristics were not influenced by the conduction system; e) The system of conduction of Espalier in T with 2 wires and 4 strings demosntrated better economic viability in relation to the other.

Aços de alta resistência e baixa liga (ARBL) têm sido bastante utilizados na fabricação de tubulações para o transporte de petróleo e gás. Entretanto, o uso destes materiais em meios com elevadas concentrações de H2S, denominados sour, tem resultado em falhas frequentes, devido à suscetibilidade destes materiais ao desenvolvimento do fenômeno de trincamento induzido pelo hidrogênio (Hydrogen Induced Cracking - HIC), assim como devido a problemas de corrosão. O desenvolvimento de diferentes processos tecnológicos para a produção de tubos de aços ARBL, tais como a laminação controlada e resfriamento acelerado, a adição de microligantes, assim como a diminuição do teor de enxofre, fósforo, carbono e manganês, tem levado à elaboração de materiais com propriedades mecânicas otimizadas, permitindo também um melhor controle da microestrutura. As perdas de dureza e resistência mecânica devidas à redução do teor de manganês, são compensadas pela adição de elementos como cromo e nióbio. Neste trabalho estão sendo comparadas a resistência à corrosão e os parâmetros de permeabilidade do hidrogênio de dois tubos de aço API 5L X65 e uma chapa API 5L X65, todos do tipo ARBL e com baixo manganês (0,27%) e alto nióbio (0,083% a 0,090%), na solução B da norma NACE, TM-0284 (2011). Para isto, foram realizados ensaios de potencial de circuito aberto (Open Circuit Potential - OCP), espectroscopia de impedância eletroquímica (Electrochemical Impedance Spectroscopy - EIS) e curvas de polarização potenciodinâmicas no eletrólito naturalmente aerado, desaerado e saturado com H2S. Os testes de permeabilidade do hidrogênio foram realizados com base na norma ASTM INTERNATIONAL G148 - 97, porém usando a célula modificada de DEVANATHAN e STACHURSKY (1962) e com H2S como veneno catódico. Os materiais foram caracterizados por microscopia óptica (MO), microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva de Raios-X (X-Ray Energy Dispersive Spectroscopy - EDS) antes e depois de testes de imersão nos diferentes eletrólitos. Caracterização dos produtos de corrosão por difração de raios-X (DRX) também foi realizada após imersão em meio saturado com H2S (sour). As análises por MO e MEV mostraram matrizes ferríticas para os três aços, com a presença de baixos teores do microconstituinte martensita/austenita (M/A), de perlita e com baixo nível de inclusões uniformemente distribuídas e com composições químicas semelhantes. Os resultados dos ensaios de corrosão mostraram que, para todos os meios investigados, o aço denominado como B apresentou a melhor resistência à corrosão, enquanto aquele denominado como C se mostrou o mais suscetível em todas as condições estudadas. Para os três aços, a resistência à corrosão apresentou a seguinte ordem crescente de acordo com o meio de exposição: meio saturado com H2S < meio naturalmente aerado < meios desaerados. Ensaios de OCP e EIS no meio saturado com H2S em um período de 24h mostraram que a resistência à corrosão aumenta com o tempo em razão da formação de uma camada de sulfeto de ferro, que, no entanto, se apresentou pouco aderente. Os resultados dos ensaios de permeação de hidrogênio mostraram que o aço denominado B, que apresentou maior resistência à corrosão em todos os meios e que não apresenta perlita em sua microestrutura, teve o maior valor de difusividade efetiva de hidrogênio, menor concentração de hidrogênio atômico na sub-superfície e menor quantidade de traps por unidade de volume. Quanto aos outros dois materiais, os resultados dos testes de permeabilidade ficaram em desacordo com os resultados da caracterização microestrutural e dos testes de resistência à corrosão, indicando que fatores diferentes dos detectados neste estudo são importantes para governar essas propriedades. / High strength low alloy (HSLA) steels have been widely used in the manufacture of pipelines for the transport of oil and gas. However, the application of these steels in media with high H2S concentrations, denominated sour, has resulted in frequent failures due to the susceptibility of these materials to the development of Hydrogen Induced Cracking (HIC) phenomena, as well as due to corrosion problems. The development of different technological processes for HSLA piping production, like controlled rolling and accelerated cooling, the addition of microalloying elements, as well as the reduction of the amounts of sulphur, phosphorus, carbon and manganese, has led to the development of materials with optimized mechanical properties, also allowing a better microstructural control. Hardness and mechanical resistance reduction due to the lowering of Mn content are compensated by niobium and chromium addition. In this work, the corrosion resistance and the hydrogen permeability parameters of two API 5L X65 steel tubes and an API 5L X65 plate, all HSLA type and with low manganese (0.27%) and high niobium (0.083% to 0.090%) contents, are compared in solution B of NACE standard TM-0284 (2011). For this, open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves were carried out in the naturally aerated, deaerated and H2S saturated electrolyte. Hydrogen permeability tests were performed based on ASTM INTERNATIONAL G148-97, but using a modified DEVANATHAN and STACHURSKY (1962) cell and with H2S as cathodic poison. The materials were characterized by means of optical microscopy (OM), scanning electron microscopy (SEM) and X-Ray Energy Dispersive Spectroscopy (EDS) prior and after immersion tests in the different electrolytes. Characterization of the corrosion products by X-ray diffraction (XRD) was also performed after immersion in the H2S-saturated (sour) medium. The OM and SEM characterization showed ferritic matrices for the three steels, with the presence of low levels of the martensite/austenite (M/A) microconstituent, perlite and with a low level of inclusions evenly distributed and with similar chemical compositions. The results of the corrosion tests showed that, for all investigated media, the steel denominated as B presented the best resistance to corrosion, whereas the one denominated as C showed to be the most susceptible in all the conditions studied. For the three steels, the corrosion resistance showed the following ascending order according to the exposure medium: H2S saturated < naturally aerated medium < deaerated media. OCP and EIS tests in the H2S-saturated medium in a period of 24 hours showed that the corrosion resistance increases over time due to the formation of an iron sulphide layer, which, however, presented little adhesion. The results of the hydrogen permeation tests showed that the steel denominated B, that presented greater corrosion resistance in all media and that does not present perlite in its microstructure, had the highest values of effective hydrogen diffusivity, the lowest concentration of atomic hydrogen in the subsurface and the smallest amount of traps per unit volume. Concerning the other two materials, the results of the permeability tests were at variance with the results of the microstructural characterization and corrosion resistance tests, indicating that factors other than those detected in this study are important to govern such properties.