Sodium hydroxide can cause cellulose to swell and can even dissolve cellulose in a narrow range of the phase diagram. It was found that for cellulose with low to moderate degree of polymerization, the maximal solubility occurs with 8~10% soda solution. In recent years, researchers found that sodium hydroxide with urea at cold temperature can dissolve cellulose better than sodium hydroxide alone. However, the lack of sufficient understanding of the NaOH and NaOH/urea dissolution process significantly constrains its applications. In order to fully understand the cellulose dissolution in alkali system, there are several aspects of problems that need to be addressed. Our focus in this study is in the interaction of cellulose with alkali solution at low temperatures, the improvement of its solubility, and the effect of hemicellulose and lignin.

1) Both the partially euryhaline Scyliorhinus canicula and the fully euryhaline Carcharhinus leucas significantly modify plasma concentrations of urea and chloride (Cl-) (and sodium (Na+)) in response to changes in environmental salinity, in order to maintain overall plasma osmolality slightly hyper- or isosmotic to the environment. C. leucas has a greater capacity for urea retention in dilute environments. In S. canicula all of these changes occur within 12 hours of transfer, with the notable exception of increasing plasma urea in response to acute transfer to elevated salinity. 2) A new technique, 51Cr-labelled erythrocytes, was developed to assess blood volume in elasmobranch fish. S. canicula displays significant haemodilution and concentration during chronic acclimation to decreased and increased environmental salinity respectively. Significant changes in blood volume were seen within 6 hours of acute salinity transfer. 3) In vivo secretion rates were measured in the rectal gland of S. canicula during both chronic and acute salinity transfer. Significant changes in Cl- clearance occur during acute transfer, as plasma Na+ and Cl- levels are modified, but do not persist in chronically acclimated animals. This is achieved through modifications in the volume and Cl- concentration of the secretory fluid. 4) C. leucas is able to significantly alter the abundance and/or recruitment of Na+, K+-ATPase in both the rectal gland and the kidney during chronic acclimation to salinity transfer. This is presumably in response to increased requirements for NaCl secretion in SW and osmolyte retention in FW respectively. S. canicula do not significantly alter abundance and/or recruitment of Na+, K+-ATPase in the principle osmoregulatory organs following chronic acclimation to salinity transfer. 5) Chronically SW acclimated C. leucas modify the proportion of ouabain-sensitive oxygen consumption in the tissues of the rectal gland in response to the secretory endocrine stimulus C-type natriuretic peptide (CNP). No such modification occurred in the rectal glands of FW acclimated C. leucas. This represents a change in the sensitivity and response to endocrine control factors during chronic acclimation to salinity transfer in this species. No such modification was seen the in the proportion of ouabain-sensitive oxygen consumption in the rectal glands of chronically acclimated S. canicula in response to CNP. These results were discussed in relation to the capacity for modification of osmoregulatory organs in partially and fully euryhaline elasmobranchs.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2006. / Härtill 5 uppsatser.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 105 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 92-93).

Thesis (M.S.) -- Mississippi State University. Dave C. Swalm School of Chemical Engineering. / Title from title screen. Includes bibliographical references.

Coal-fired electricity production is the major emitter of CO2 and other greenhouse gases including NOx and SOx. Microalgae-based CO2 mitigation systems have been proposed to reduce the net CO2 emission from coal-fired power plants. This study focused on developing an optimum culture media and exploring the possibilities for recycling nutrients, which were added as commercial mineralized chemicals at the beginning of cultivation. In order to release the nutrients embedded in the cells so that they can be used as a nutrient source for new cells, Scenedesmus biomass was digested by anaerobic bacteria. Results showed that thermal pretreatment enhanced the methane production rate for the first 7 days of digestion. Three operational factors were tested: heating temperature, heating duration and NaOH dosage. The combination of 10 min heating with 3~6% NaOH at 50 °C gave the highest cell wall destruction for all samples except oven-dried algae. The anaerobic digestate, rich in mineralized nutrients including ammonium and phosphate, potassium and magnesium ions, was tested as a possible nutrient source for the algae cultivation. To cope with the high solid content of the digestates, the dosage of the digestates was reduced or the solid particles were removed prior to addition to the microalgae. Both approaches worked well in terms of providing nutrients with minimal effect on light penetration. Using digestates without any sterilization did not cause contamination or other deleterious effects on the Scenedesmus growth rate. Harvesting microalgae cells was critical to ensure a continuous and robust growth rate. The used media could be recycled at least four times without altering the algae growth. Nutrient replenishment was the key for a healthy culture when used media was incorporated. The combination of used media and digestates can sustain a normal algae growth. Life cycle assessment was conducted on the system including the photobioreactor, the anaerobic digester, the biomass settling and dewatering and used media and nutrient recycling. Considering methane as the energy source, the overall energy return of the system was 2.4. CO2 mitigation rate was about 39% under current mitigation system.

In order to utilize algae to fix CO2 and reduce Greenhouse gas emissions, large-scale, year-round algae cultivation will be required. This will require alga species that thrive in colder weather with media recipes based on commercially available fertilizers. The objectives of this study were to evaluate the effect of using commercial based media and the effect of pH when growing the cold-temperature algae Chloromonas rosae var. psychrophila. Commercial grade media ingredients urea, potash, triple superphosphate, and Sprint 330® were used to provide nitrogen, potassium, phosphorus, and EDTA with iron, respectively. The commercial grade media supported growth similar to the growth found with the lab-based media typically used. Additionally, tests were done to determine the effect of the pH of the media. Testing with initial pH targets of 5, 6, 7 and 8 using the laboratory media, showed that growth was not sufficient at a pH around 8. However both the laboratory and commercial grade media performed well when the initial pH was between 5 and 7, and no significant difference in algal growth was measured within this pH range.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-05T12:19:58Z No. of bitstreams: 1 PGCS16MA125.pdf: 1279709 bytes, checksum: 6ffcf0d5b6dcb6ee19add0eb5a3f0b0a (MD5) / Made available in DSpace on 2017-12-05T12:19:58Z (GMT). No. of bitstreams: 1 PGCS16MA125.pdf: 1279709 bytes, checksum: 6ffcf0d5b6dcb6ee19add0eb5a3f0b0a (MD5) Previous issue date: 2016-02-04 / CNPq / This study aimed to evaluate the effect of nitrogen fertilizers added to the soil on N leaching, volatilization and common bean yield. Three experiments were conducted, all using a clayey Humic Hapludox with medium organic matter content. The fertilizers used were: conventional Urea, Super N®, Kimcoat N®, Nitro Mais®, Super Nitro®, Producote®, Sulfammo Meta 22®, Sulfammo Meta 29® and Ammonium Nitrate. The first study aimed to evaluate the effect of topdressing N fertilizers, combined with two lime application forms, on ammonia volatilization. This experiment was conducted in controlled conditions, in Lages, SC. Soil samples were placed in plastic pots and coupled to volatilization chambers. Treatments included the above fertilizers, except Sulfammo Meta 22®, at a rate of 157 mg of nitrogen (N) per experimental unit, plus a control without N, combined with incorporated or broadcast liming. Volatilization was determined at 1, 2, 4, 7, 14, 21, 28 and 35 days after fertilizer application. Liming form did not affect volatilization from amidic fertilizers but increases from ammonium fertilizers. The second experiment evaluated N leaching after fertilizer addition under laboratory conditions, in Lages, SC. Soil samples were placed in PVC columns. The fertilizers, except Sulfammo Meta 29®, were applied at 5 cm deep at a N rate of 400 mg column-1. Distilled water (300 ml column-1) was applied weekly, during 13 weeks. The ammonium leaching was small and did not differ between treatments. The amidic fertilizers caused the highest leaching of nitrate. Thus, the urea protection mechanisms were not efficient in reducing N losses by leaching. The third study aimed to evaluate the response of bean to nitrogen fertilizers applied in top dressing. The experiment was conducted in Vacaria, RS, in an area previously cultivated with an apple orchard for twenty years. The fertilizers, except Sulfammo Meta 22®, were topdressed at a N rate of 60 kg ha-1. The average grain yield was 3770 kg ha-1 and, like all other attributes, was not influenced by the addition of any fertilizer, possibly due to the high N availability in the soil as a result of the organic matter mineralization during the growing season. Thus, apparently there is no need for topdressing for bean under these conditions / Este trabalho visou avaliar o efeito da adição de fertilizantes nitrogenados ao solo na lixiviação, na volatilização e no rendimento de feijoeiro. Para isso foram implantados três experimentos, todos utilizando um Latossolo Bruno Aluminoférrico típico, argiloso e com médio teor de matéria orgânica. Os fertilizantes utilizados foram: Ureia convencional, Super N®, Kimcoat N®, Nitro Mais®, Super Nitro®, Producote®, Sulfammo Meta 22®, Sulfammo Meta 29® e Nitrato de Amônio. O primeiro estudo objetivou avaliar o efeito da aplicação dos fertilizantes em cobertura, associados a formas de aplicação de calcário, na volatilização de amônia. Ele foi realizado em câmara de crescimento, em Lages, SC. As amostras de solo foram acondicionadas em potes plásticos e acoplados a câmaras de volatilização. Os tratamentos foram constituídos pelos fertilizantes citados, na dose de 157 mg de nitrogênio (N) por unidade experimental, exceto o Sulfammo Meta 22®, além da testemunha sem N, combinados com calagem, superficial ou incorporada. A volatilização foi determinada aos 1, 2, 4, 7, 14, 21, 28 e 35 dias após a aplicação dos fertilizantes. As formas de calagem não influenciaram a volatilização a partir dos fertilizantes amídicos mas aumenta a de fertilizantes amoniacais. O segundo experimento teve como objetivo avaliar a lixiviação de N decorrente da adição dos fertilizantes, também em laboratório, em Lages, SC. Amostras de solo foram acondicionadas em colunas de PVC. Os fertilizantes, exceto o Sulfammo Meta 29®, foram aplicados a 5 cm de profundidade, na dose de 400 mg coluna-1 de N. Foram feitas 13 percolações semanais de 300 ml por coluna. A lixiviação de amônio foi pequena e não diferiu entre os tratamentos. Os fertilizantes amídicos apresentaram as maiores quantidades de nitrato lixiviadas. Portanto, os mecanismos de proteção da ureia não foram eficientes na redução das perdas por lixiviação de nitrogênio. O terceiro estudo teve como objetivo avaliar a resposta do feijoeiro aos fertilizantes nitrogenados aplicados em cobertura. O experimento foi conduzido em Vacaria, RS, em um Latossolo cultivado anteriormente por vinte anos com um pomar de macieira. Os fertilizantes, exceto o Sulfammo Meta 22®, foram aplicados em cobertura, na dose de 60 kg ha-1 de N. O rendimento médio de grãos foi de 3770 kg ha-1 e, assim como as demais variáveis, não foi influenciado pela adição de nenhum dos fertilizantes, possivelmente devido à alta disponibilidade de N no solo em função da mineralização da matéria orgânica durante o ciclo vegetativo. Sendo assim, verifica-se que não há necessidade da adição de N de cobertura para o feijoeiro nessas condições

Orientador: Marcelo Andreotti / Banca: Salatiér Buzetti / Banca: Aloísio Costa Sampaio / Resumo: O abacaxizeiro é classificado como uma cultura exigente em fertilidade do solo, sendo o N o nutriente mais importante para o desenvolvimento da planta e aumento do tamanho e massa dos frutos. O objetivo deste trabalho foi avaliar quantitativamente e qualitativamente os frutos de abacaxi cv. Smooth Cayenne na região noroeste do estado de São Paulo, utilizando fontes e doses de N, aplicado antes e após a indução do florescimento, em solo corrigido quanto ao teor de potássio. O trabalho foi conduzido na Fazenda Água Limpa, no município de Guaraçaí-SP, em um solo Latossolo Vermelho-Amarelo. As mudas foram plantadas em sulcos na superfície do solo, no dia 17/03/2009, com espaçamento de 1,10m entrelinhas, 0,40m entre fileiras e 0,40m entre plantas, com densidade aproximada de 33.000 plantas ha-1, sendo cada parcela composta por quatro fileiras duplas com 56 plantas/parcela no total. A indução floral foi realizada em duas épocas, em virtude da pouca porcentagem de plantas induzidas na primeira, ou seja, nos dias 21/02/2009 e 05/05/2009, com as respectivas colheitas dos frutos realizada nos dias 12/09/2009 (203 dias após a indução) e 27/11/2009 (206 dias após a indução). As avaliações realizadas foram duas análises nutricionais da folha "D", uma antes e outra após a indução floral, e duas análises dos frutos, devido à realização de duas colheitas. O delineamento experimental adotado foi o de blocos ao caso com quatro repetições, em esquema fatorial 3x5 (para 1ª análise foliar sem efeito de época) e 2x3x4 (para a 2ª análise da folha e as duas análises dos frutos), sendo composto por duas épocas de aplicação de N: toda a dose aplicada no dia 06/10/2008 (antes da indução floral) ou toda no dia 12/06/2009 (após a indução floral), 3 fontes de N, sulfato de amônio, uréia e nitrato de amônio, e quatro doses de N (7,5; 15; 22,5 e 30 g planta-1) ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Pineapple plant is demanding in fertility of soil, and N is the most important nutrient for the development of plant and increase of size and mass of fruits. The objective of this work was to evaluate quantity and quality of fruits of pineapple cv. Smooth cayenne in the northwest area of São Paulo State, using sources and doses of N, applied before and after the flowering induction, in soil fertilized with potassium. The work was conducted at Água Limpa farm, in Guaraçaí-SP, in a Red-yellow Latosol. The seedlings were planted in furrows at soil surface, in 03/17/2009, with spacing of 1.10m between double lines, 0.40m between single lines and 0.40m among plants, with approximate density of 33,000 plants ha-1, being each plot composed of four double lines with 56 plants/plot in the total. The flowering induction was accomplished in two times, due to little percentage of plants induced in the first time, in other words, in 02/21/2009 and 05/05/2009, with the respective crops of the fruits accomplished in 09/12/2009 (203 days after the induction) and 11/27/2009 (206 days after the induction). The evaluations were: two nutritional analyses in "D" leaf, one before and other after the flowering induction, and two analyses of fruits, due to the accomplishment of two crops. A randomized block design with four repetitions in a factorial scheme 3x5 (for 1st leaf analysis without time effect) and 2x3x4 (for 2nd leaf analysis and two fruit analyses), being composed by two times of N application: the total dose accomplished in 10/06/2008 (before the floral induction) or total dose in 06/12/2009 (after the floral induction), 3 sources of N, ammonium sulfate, urea and ammonium nitrate, and four N doses (7.5; 15; 22.5 and 30 g plant-1) was used. Ammonium sulfate provided higher leaf N and S content as applied on pineapple plant before or after the floral induction. For the fruits harvested ... (Complete abstract click electronic access below) / Mestre