<p>This thesis work aimed to provide a better knowledge of inclusion behavior at the steel-slag interface. All results are based on mathematical modeling of liquid and solid inclusion separation to the slag. The model descriptions of the inclusion transfer are based on the equation of motion at the system. It is assumed that the inclusion transfer is governed by four forces acting on the inclusion as it has reached the steel-slag interface. These are the buoyancy force, the added mass force, the drag force and the rebound force. The models assume two cases of inclusion separation depending on the inclusion Reynolds number. In the case where Reynolds number is larger or equal to unity, Re≥1, a steel film is formed between the inclusion and the slag. This steel film must first be drained before the inclusion can separate to the slag. If Reynolds number, Re<1, then no steel film is formed and the inclusion will be in direct contact with the slag. The mathematical models also propose three types of inclusion behavior as the inclusion crosses the steel-slag interface. The inclusion can either, pass and separate to the slag, oscillate at the interface with the possibility of reentering the steel bath with the steel flow or it can remain at the interface not completely separated to the slag. A parameter study for 20 μm inclusions showed that the most important parameters controlling the inclusion behavior at the steel-slag interface are the slag viscosity and the interfacial tensions between the phases. For 100μm inclusions also the inclusion density affects the inclusion behavior. The models were applied to ladle and tundish conditions. Since the slags in the chosen industrial conditions have not been studied experimentally before, estimations of the important physical property parameters were made. Future measurements will therefore be needed in order to make predictions of inclusion transfer behavior at the steel-slag interface which are more relevant for the industry. The main conclusion is that useful plots can be made in order to illustrate the tendency for the inclusion transfer and how to manipulate the physical property parameters in order to increase the inclusion separation in ladles and tundishes.</p>

Dirvožemio fizikinės savybės yra svarbios dirvožemio drėgmės ir oro režimui, augalų apsirūpinimui maisto medžiagomis. Jos daro įtaką augalų biologinio potencialo formavimuisi, taigi ir derlingumui. Iki šiol Lietuvoje išlieka vyraujanti tradicinė žemės dirbimo sistema, paremta rudeniniu giliu dirvų arimu verstuviniais plūgais. Pastaraisiais metais Lietuvoje pastebimas vis didėjantis susidomėjimas supaprastintu žemės dirbimu. Daugiau nei 50 šalies ūkio subjektų jau taiko praktikoje supaprastintą žemės dirbimą ir, tikėtina, kad ateityje šis skaičius dar didės. Todėl moksliniai tyrimai, kuriuose būtų tiriamos alternatyvios įprastiniam žemės dirbimui sistemos, yra aktualūs. Naudojant vis intensyvesnes žemės dirbimo ir tręšimo technologijas dirvožemyje ima stigti organinių medžiagų, todėl sparčiai vyksta dirvožemio degradacija. Organinės medžiagos lėtina ir stabdo dirvožemyje vykstančius neigiamus procesus, todėl moksliniai tyrimai, susiję su žaliąja trąša bei šiaudų įterpimu į dirvą, tampa vis aktualesnė žemdirbių tarpe. Stacionarus dviejų faktorių lauko eksperimentas įrengtas LŽŪU bandymų stotyje. Bandymų vietos dirvožemis – giliau karbonatingas glėjiškas išplautžemis (Endocarcalic Endohipogleyc Luvisol), vidutinio sunkumo priemolis ant smėlingo lengvo priemolio. Bandymų metu tirta supaprastinto žemės dirbimo, šiaudų bei žaliosios trąšos įterpimo ir tiesioginės sėjos į neįdirbtą dirvą įtaka dirvos fizikinėms savybėms ir sliekų kiekiui. Gauti bandymų rezultatai patvirtina, kad... [toliau žr. visą tekstą] / Soil physical properties are significant for soil moisture and air movement treatment, providing nutrients for plants. They affect the biological potential formation of plants, and therefore fertility. So far, the traditional tillage system, based on deep mouldboard ploughing in autumn, is predominant in Lithuania. In these latter years, the interest in reduced soil tillage is increasing in Lithuania. More than 50 national agriculture subjects are already practising reduced soil tillage and it seems likely that this number would increase. So that scientific inquiries in alternatives of conventional tillage system are relevant. While using intensive soil tillage and fertilization technologies, begins the deficiency of organic matters and the degradation of soil is occuring rapidly. Organic matter slows down and stops the ongoing negative processes in the soil and therefore research related to green manure and straw incorporation becomes more and more important among farmers. Stationary two-factor field experiment is located at the Experimental Station of Lithuanian University of Agriculture. The soil of the experimental area (Endocarcalic Endohipogleyc Luvisol), medium weight loam over light sandy loam. The influence of reduced soil tillage systems or no-tillage (direct drilling) systems on soil physical properties and quantity of earthworms is analyzed in the experiment. The test results confirm that reduced soil tillage or no-tillage (direct drilling) systems are not... [to full text]

Master of Science in Veterinary Science / A investigation into soil nutrient and the change soil physical properties was carried out for three pasture systems for dairy cows; the complementary forage rotation (CFR) which comprised of brassica (Brassica napus )/clover (Trifolium resupinatum ) and maize (Zea mays) capable of achieving more than 40 t/ha, the typical intensive pasture (PI) with kikuyu grass (Penisetum clandestinum) over-sown with ryegrass ( Lolium multiflorum ) and the extensive system (PE); on two soil types (brown chromosol and black vertisol) . The study demonstrated that the CFR system was capable of doubling its yield by using similar fertilizers (N, P and K) and water inputs compared to these of the PI system resulting of greater nutrients (N and K) and water use efficiencies. Overall, the nutrient lost through runoff water was very limited for two intensive systems and nearly nil for PE system. Also similar trends were observed for soil physical properties in the intensive systems except for the topsoil (0-10 cm) where light acidification (P= 0.04) was recorded in the CFR probably due to the soil works before the maize sowing.

Master of Science in Veterinary Science / A investigation into soil nutrient and the change soil physical properties was carried out for three pasture systems for dairy cows; the complementary forage rotation (CFR) which comprised of brassica (Brassica napus )/clover (Trifolium resupinatum ) and maize (Zea mays) capable of achieving more than 40 t/ha, the typical intensive pasture (PI) with kikuyu grass (Penisetum clandestinum) over-sown with ryegrass ( Lolium multiflorum ) and the extensive system (PE); on two soil types (brown chromosol and black vertisol) . The study demonstrated that the CFR system was capable of doubling its yield by using similar fertilizers (N, P and K) and water inputs compared to these of the PI system resulting of greater nutrients (N and K) and water use efficiencies. Overall, the nutrient lost through runoff water was very limited for two intensive systems and nearly nil for PE system. Also similar trends were observed for soil physical properties in the intensive systems except for the topsoil (0-10 cm) where light acidification (P= 0.04) was recorded in the CFR probably due to the soil works before the maize sowing.

Master of Science in Veterinary Science / A investigation into soil nutrient and the change soil physical properties was carried out for three pasture systems for dairy cows; the complementary forage rotation (CFR) which comprised of brassica (Brassica napus )/clover (Trifolium resupinatum ) and maize (Zea mays) capable of achieving more than 40 t/ha, the typical intensive pasture (PI) with kikuyu grass (Penisetum clandestinum) over-sown with ryegrass ( Lolium multiflorum ) and the extensive system (PE); on two soil types (brown chromosol and black vertisol) . The study demonstrated that the CFR system was capable of doubling its yield by using similar fertilizers (N, P and K) and water inputs compared to these of the PI system resulting of greater nutrients (N and K) and water use efficiencies. Overall, the nutrient lost through runoff water was very limited for two intensive systems and nearly nil for PE system. Also similar trends were observed for soil physical properties in the intensive systems except for the topsoil (0-10 cm) where light acidification (P= 0.04) was recorded in the CFR probably due to the soil works before the maize sowing.

Thesis (M.S.); Submitted to Iowa State Univ., Ames, IA (US); 12 Dec 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "IS-T 2608" Maria Ambert Sanchez. 12/12/2003. Report is also available in paper and microfiche from NTIS.

Orientador: Angela Cristina Cilense Zuanon / Resumo: Avaliou-se a dureza superficial, rugosidade, porosidade, resistência a compressão, atividade antibiofilme, atividade metabólica do biofilme (XTT) e observou-se a aderência e formação do biofilme em microscopia eletrônica de varredura (MEV) de um cimento de ionômero de vidro (CIV) de alta viscosidade (Ketac Molar Easy Mix), associado a nanopartículas de óxido de zinco (NPZnO) a 2% ou ao diacetato de clorexidina (CLX) nas concentrações de 0,5%, 1% e 2%. Como grupo controle utilizou-se o próprio CIV. Para os testes físicos, mecânicos e atividade antibiofilme foram confeccionados 10 corpos de prova por grupo, para o teste de XTT e MEV, foram utilizados 5 e 2 corpos de prova por grupo respectivamente. A atividade antibiofilme foi avaliada para biofilme monoespécie de Streptococus mutans, no período de incubação de 1, 7, 14 e 21 dias. Realizou-se contagem das unidades formadoras de colônia por mililitro (UFC/mL) e a atividade metabólica do biofilme, assim como a observação em MEV foram avaliadas nos os períodos de 1 e 7 dias . Os dados foram analisados estatisticamente e atenderam quanto à normalidade e a homogeneidade de variâncias. Realizou-se análise paramétrica de variância (ANOVA) para verificar diferença estatística seguida pelo teste de Tukey. Todos os testes foram realizados com um nível de significância de 5%. Avaliação qualitativa em MEV foi realizada para a observação da aderência e formação de biofilme. No teste de dureza superficial todos os grupos apresentaram diminui... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: It was evaluated the surface hardness, roughness, porosity, compressive strength, antibiofilm activity, metabolic activity of the biofilm (XTT) and the adherence and formation of the biofilm in Scanning Electron Microscopy (SEM) of a glass ionomer cement (GIC) of high viscosity (Ketac Molar Easy Mix), associated with 2% zinc oxide (NPZnO) nanoparticles or chlorhexidine diacetate (CLX) at concentrations of 0.5%, 1% and 2%. As a control group, the GIC itself was used. For the physical, mechanical and antibiofilm activity tests, 10 specimens were prepared per group, for the XTT and MEV test, 5 and 2 specimens were used per group, respectively. The antibiofilm activity was evaluated for monospecific biofilm of Streptococus mutans, during the incubation period of 1, 7, 14 and 21 days. The colony forming units were counted per milliliter (CFU / mL) and the metabolic activity of the biofilm, as well as the SEM observation, were evaluated in the 1 and 7 day periods. The data were analyzed statistically and attended to the normality and homogeneity of variances. We performed a parametric analysis of variance (ANOVA) to verify statistical difference followed by the Tukey test. All tests were performed with a significance level of 5%. Qualitative evaluation in SEM was performed for the observation of adhesion and biofilm formation. In the superficial hardness test, all groups showed decreased values, being the lowest values of the CLX groups. For the surface roughness, only the group wi... (Complete abstract click electronic access below) / Doutor

Some chosen physical properties have been observed in the field experiment on the land of Stagra, s. r. o., Studená in 2009. There have been compared two technologies "minimum tillage" (MT) and "conventional tillage" (CT). There was evaluated especially bulk density (Or), porosity and soil compaction. Bulk density was statistical significantly higher under conservation tillage than under ploughing in soil profil at the depth to 0,2 m. But at the depth more than 0,25 m bulk density was higher (it means less favourable) under CT than under MT. It can be concluded, that the minimum tillage doesn´t deteriorate the compaction in the subsoil. The average values were not higher than critical levels of damaged compaction for sandy-loam soil. The soil compaction measurement confirmed this trend. The values of total porosity (Pc) show nearly the same conclusions as Or. The most favourable values of Pc occur in topsoil, which is tilled.

Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12199号 / 論工博第3988号 / 新制||工||1438(附属図書館) / 26271 / UT51-2008-C969 / (主査)教授 堀井 文敬, 教授 渡辺 宏, 教授 金谷 利治 / 学位規則第4条第2項該当

A presente dissertação, desenvolvida no âmbito da pesquisa em poéticas visuaise intitulada Delicadeza incisivas:ensaiosmateriais com pequenos objetos cotidianos, tem como foco principal de análise um grupo de trabalhos - entre desenhos, objetos e instalações - realizados no ano de 2007e 2008.Na produção analisada, as qualidades físicas dos materiais empregados - em sua maioria objetos cotidianos de pequenas dimensões - são signos de fundamental importância. Dentre as operações presentes no processo de trabalho - pensado enquanto ensaio visual-, abordo dois conceitos operatórios que agem diretamente sobre a tatilidade dos materiais: a repetição (de gestos, de materiais e de módulos) e o emprego de estruturas geométricas - instâncias estas que se apresentam como estratégias organizacionais. O presente estudo visa analisar não apenas alguns processosem arte que se veiculam a fisicalidade presente nos materiais utilizados - principalmente aqueles aliados aos processos cumulativos e às conformações geométricas - mas,também, o comportamento dessestrabalhos no espaço. / The current dissertation developed on the extent of visual poetics research and entitled Delicadezas incisivas:ensaios materiais com pequenos objetos cotidianos ("Incisive delicacies: material essayswith small everyday objects") presents as main focus of analysis a group of works - among drawings, objects and installations - performed in 2007and 2008.The physical qualities of the materiais employed in the production analyzed - mainly small everyday objects - are signs of fundamental importance. Among the operations presented on the work process - thought as visual essay- I treat two opera tive concepts that act directly on the materiais: the repetition (of gestures, of materiais and of modules) and the employment of geometrical structures - being these instances presented as organizational strategies. The current study aims to analyze not only some of the processes in art which diffuse physicality presented in the used materiais but also the behavior of these works in space.