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Desempenho de unidades de pré-limpeza de frutos de macadâmia (M. integrifolia)Piza, Pedro Luís Blasi de Toledo [UNESP] 16 December 2005 (has links) (PDF)
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piza_plbt_dr_botfca.pdf: 576119 bytes, checksum: e10fb2efd0d10e64fe9dc7061c5a81e8 (MD5) / A pós-colheita da noz macadâmia é uma das etapas mais críticas de sua cadeia produtiva, as baixas produtividades nos primeiros anos de vida dos pomares não permitem que os agricultores realizem grandes investimentos neste período, iniciando, assim, um processo de improvisações que se perpetuará ao longo do tempo. Este trabalho teve como principal objetivo melhorar o rendimento operacional de um processo de pré-limpeza de macadâmia, desenvolvendo, a partir de um sistema existente, uma nova unidade, com capacidade de receber e processar, no mínimo, 8.000 kg de produto por dia. O experimento foi realizado em uma fazenda situada no município de Dois Córregos, Estado de São Paulo, nas safras de 2003, 2004 e 2005. A partir do processo existente foram desenvolvidas 3 novas unidades. As duas primeiras apresentaram aumentos na produtividade e reduções nos custos operacionais, entretanto, não atenderam as condições de recebimento e processamento. A terceira unidade, representou a somatória dos conhecimentos obtidos nas análises anteriores, e, atendeu os objetivos propostos no presente trabalho. A análise econômica dos custos para migrar do processo existente para a unidade de melhor rendimento mostrou que, os investimentos em equipamentos e automação foram pagos em aproximadamente 50 dias de processamento. / The macadamia nut post-harvest is one of the most critical stages of the productive chain, the low orchards productivity in the first life years does not allow farmers much investments in this period, initiating, thus, a process of improvisations that will be perpetuated trough the years. This work had as main objective to improve the efficiency of a cleaning macadamia process. It was developed a new unit based as an existing system with capable to process, at least, 8,000 kg of product per day. The experiments were carried out in a farm situated in Dois Córregos city, São Paulo, during harvest season of 2003, 2004 and 2005. From the existing process three new units were developed. The first two ones shoud increases in productivity and reductions in operational costs, however, it did not attend the necessities of receiving and processing. The third unit, represented incorporation of the knowledge obtained in the previous analyses, and, fulfilled the objectives of this work. The costs analysis to go from the existing process to the better income unit, showed that, the investments in equipment and automation had been paid in approximately 50 processing days.
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Desempenho de unidades de pré-limpeza de frutos de macadâmia (M. integrifolia) /Piza, Pedro Luís Blasi de Toledo, 1964- January 2005 (has links)
Resumo: A pós-colheita da noz macadâmia é uma das etapas mais críticas de sua cadeia produtiva, as baixas produtividades nos primeiros anos de vida dos pomares não permitem que os agricultores realizem grandes investimentos neste período, iniciando, assim, um processo de improvisações que se perpetuará ao longo do tempo. Este trabalho teve como principal objetivo melhorar o rendimento operacional de um processo de pré-limpeza de macadâmia, desenvolvendo, a partir de um sistema existente, uma nova unidade, com capacidade de receber e processar, no mínimo, 8.000 kg de produto por dia. O experimento foi realizado em uma fazenda situada no município de Dois Córregos, Estado de São Paulo, nas safras de 2003, 2004 e 2005. A partir do processo existente foram desenvolvidas 3 novas unidades. As duas primeiras apresentaram aumentos na produtividade e reduções nos custos operacionais, entretanto, não atenderam as condições de recebimento e processamento. A terceira unidade, representou a somatória dos conhecimentos obtidos nas análises anteriores, e, atendeu os objetivos propostos no presente trabalho. A análise econômica dos custos para migrar do processo existente para a unidade de melhor rendimento mostrou que, os investimentos em equipamentos e automação foram pagos em aproximadamente 50 dias de processamento. / Abstract: The macadamia nut post-harvest is one of the most critical stages of the productive chain, the low orchards productivity in the first life years does not allow farmers much investments in this period, initiating, thus, a process of improvisations that will be perpetuated trough the years. This work had as main objective to improve the efficiency of a cleaning macadamia process. It was developed a new unit based as an existing system with capable to process, at least, 8,000 kg of product per day. The experiments were carried out in a farm situated in Dois Córregos city, São Paulo, during harvest season of 2003, 2004 and 2005. From the existing process three new units were developed. The first two ones shoud increases in productivity and reductions in operational costs, however, it did not attend the necessities of receiving and processing. The third unit, represented incorporation of the knowledge obtained in the previous analyses, and, fulfilled the objectives of this work. The costs analysis to go from the existing process to the better income unit, showed that, the investments in equipment and automation had been paid in approximately 50 processing days. / Orientador: Widsney Alves Ferreira / Coorientador: Marco Antonio Martin Biaggioni / Banca: José Armando Xavier / Banca: Antonio Carlos de O. Ferraz / Banca: João Domingos Biagi / Banca: Clovis Isberto Biscegli / Doutor
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Synthesis, characterization and application of amine-modified Macadamia nutshell adsorbents and ion imprinted polymers for the sequestration of Cr(VI) ions from aqueous solutionNchoe, Obakeng Boikanyo 08 1900 (has links)
M. Tech (Department of Chemistry, Faculty of Applied and Computer Sciences) Vaal University of Technology. / Persisting challenges associated with remediation of heavy metals from aqueous media have stirred the need for enhancement of current technologies. Cellulosic agro waste materials (AWM) as well as ion-imprinted polymers (IIP) have received ardent attention from researchers. These materials are often employed in the following industries: water and wastewater treatment, medical, pharmaceutical and packaging. Applications in water and wastewater treatment have gained significant interest due to desirable features they possess. In the case of AWM, these features include a tuneable surface area and poor porosity, basic surface functional groups and chemical stability. Some desired features in IIP include adsorption sites compatible for the ion imprint obtained after leaching with suitable reagents, rigidity and reusability. The efficacy of employing AWM and IIP for the remediation of toxic chromium from aqueous solution was explored. The current study is made up of part A and B. In part A, Macadamia nutshell powder was treated using HNO3, NaOH, as well as Fenton’s reagent. The three materials underwent a new modification which involved reacting treated adsorbents with cetyltrimethylammonium chloride (CTAC), followed by immobilization of 1,5' diphenylcarbazide (DPC) ligand. The adsorbents were ultimately washed, dried and stored for Cr(VI) batch adsorption experiments. Part B involved a synthesis of IIP and their non-imprinted polymer counterpart (NIP) for Cr(VI) sequestration in aqueous solution. This was done by precipitation polymerization of functional monomers, crosslinker and DPC-Cr(VI) complex as a template. Non-imprinted polymers were fashioned in a manner like that of IIP but with the exclusion of Cr(VI) ion template.
Characterizations of the adsorbents were done using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray fluorescence (XRF), and carbon, hydrogen, nitrogen and sulphur (CHNS) analyzer. Batch adsorption experiments were done and parameters such as solution pH, adsorbent dosage, initial Cr(VI) concentration and contact time were optimized.
Working solutions were analyzed using ultraviolet-visible (UV-Vis) and atomic absorption (AA) spectroscopy. Adsorption parameters found to be optimum for DPC immobilized cellulosic adsorbents were pH 1.4, adsorbent mass of 0.1 g, 100 mg/L initial concentration and 125 minutes of contact time. The adsorption parameters determined to be optimum for IIP and NIP were pH 2.6, 0.2 g adsorbent mass, 80 mg/L initial concentration and 240 minutes of contact time. Reusability studies demonstrated the potential of adsorbents to remove Cr(VI) ions from aqueous media after successive adsorption-desorption cycles. Selectivity studies indicated that DPC immobilized adsorbents as well as IIP were able to selectively adsorb Cr(VI) ions from aqueous media in the presence of Zn(II), Cu(II), Co(II) and NI(II) ions. Kinetic models revealed that DPC immobilized cellulosic adsorbents and synthetic IIP were most fitting for pseudo-second order and pseudo first order, respectively. On the other hand, adsorption isotherm studies demonstrated that DPC immobilized cellulosic adsorbents and synthetic polymers were best fit for Freundlich and Langmuir adsorption isotherm, respectively.
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Macadamia nutshell powder grafted with 1,5’-diphenylcarbizide for enhanced removal of Cr(VI ) from aqueous solutionMaremeni, Londolani Charity 08 1900 (has links)
M. Tech (Department of Chemistry, Faculty of Applied and Computer Sciences) Vaal University of Technology. / Agricultural waste such as Macadamia nutshells are currently receiving more attention for removal of hexavalent chromium (Cr(VI)). However, they have low adsorption capabilities when used in their raw form. In this study, the efficiency of using Macadamia nutshell powder modified with different concentrations of hydrogen peroxide, grafted with 1,5’-diphenylcarbizide (DPC) for the removal of hexavalent chromium from aqueous solution was explored. The effects of various parameters controlling adsorption of Cr(VI) onto Macadamia adsorbents such as initial concentration, contact time, adsorbent concentration and pH were investigated. The optimal operating parameters for Macadamia nutshells treated with hydrogen peroxide (MHP) adsorbents were determined to be 75 mg/L, 3 h, 0.1 g and pH 1. The optimal operating parameters for Macadamia nutshells treated with hydrogen peroxide and grafted with 1,5’-diphenylcarbizide (MHPD) were determined to be 150 mg/L, 1 h, 0.1 g and pH 3. Fourier transform infrared (FTIR) spectroscopy of the adsorbents revealed that treated MHP showed amino groups attached to the adsorbents. Thermogravimetric analysis (TGA) revealed that the grafted material lowered the thermal stability from 180◦C to 300◦C due to volatile nature of DPC. The surface of the MHPD materials was rough due to grafting. The results showed that the 1,5’-diphenylcarbazide treatment improved the removal efficiency of Cr(VI).
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Plasma biomass gasification in a 15 kW pilot facilityMaseko, Keabetswe January 2020 (has links)
Plasma gasification experiments were conducted on sucrose and crushed macadamia nutshells. The pilot-scale plasma gasification system used comprises a 15 kW DC plasma torch fitted to a 5 L gasification reactor. The DC plasma torch has an efficiency of ~30 % with most of the energy lost in the torch anode.
For the macadamia nutshells, the plasma input-power was set at 9, 11 and 14 kW. At each power input setting, four different feed rates were investigated, namely 0.5, 0.7, 1.04 and
1.14 kg/h. It was observed that as the power increases, conversion increases from 48 % at 9 kW to higher than 80 % at 14 kW. It was also observed that higher mass feed rates increase the conversion. The lower heating values of the syngas produced during gasification increased with higher power inputs and higher feed rates. At a feed rate of 1 kg/h, the maximum calorific power value was 3.45 kW, at a torch setting of 14 kW. The highest power values obtained was slightly more than 4 kW.
The effect of equivalence ratio (ER) was evaluated on the plasma gasification of sucrose. ER values of 1 and 2 were investigated. With an ER of 1, the CO/H2 ratio was 1.8 and the CO/CO2 ratio was 109. With an ER of 2, the CO/H2 ratio was 1.73, and the CO/CO2 ratio 18. As expected, an increase in ER enhances the formation of CO2. A low ER thus results in higher syngas quality.
At equivalent conditions the homogenous, crystalline sucrose yielded a CO/CO2 ratio of 109, significantly higher than the 29 for plasma gasification of the macadamia nut shells. A contributing factor to having better quality syngas, was the smaller the average particle diameter of the sucrose, 0.4 mm, compared to the 10 mm of the crushed macadamia nut shells was. Another contributing factor could be that the available carbon in the macadamia nut shells structure are more strongly bonded than in sucrose.
For additional insight, kinetic data for the pyrolysis of sucrose, fructose and glucose were obtained using a TGA-FTIR hyphenated system, at much lower heating rates than anticipated in plasma system, and TGA-DTG experiments on macadamia nut shells. Dynamic studies were performed on sucrose, fructose and glucose at heating rates of 5, 10, 15, 20 and 50 °C/min in an atmosphere of nitrogen flowing at 50 mL/min, and for the macadamia shell at heating rates of 5, 10 and 20 °C/min in an atmosphere of nitrogen flowing at 50 mL/min. The sugars yielded 80 % to 85 % conversion into gaseous products, while the conversion of the shells approached 90 %; the residue was biochar. The FTIR spectra showed the major products that form from the pyrolysis of sugars to be CO2, H2O, along with large quantities C-H-O-containing compounds, amongst them C5H4O2 and C6H6O3. The latter two compounds are probably condensible. / Dissertation (MEng)--University of Pretoria, 2020. / Chemical Engineering / MEng / Unrestricted
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Preparation of chemically modified Macadamia nutshells for adsorptive removal of selected heavy metalsNtuli, Themba Dominic 10 1900 (has links)
M. Tech. (Chemistry, Faculty of Applied and Computer Science), Vaal University of Technology / The abundance of agricultural waste materials has led to its use as adsorbents for trace metal adsorption. The raw Macadamia nutshell (RMN) powder was treated with a hydrochloric acid solution to obtain acid modified Macadamia nutshells (AMM), and with sodium hydroxide solution to obtain base modified Macadamia nutshells (BMM). Then, the AMM and BMM materials were grafted with 0.5 M, 1 M, and 2 M acrylic acid. The different AMM grafted materials were labelled 0.5 GAM, 1 GAM and 2 GAM representing the different grafting ratios. The same naming order was followed for the BMM grafted materials, that is, 0.5 GBM, 1 GBM and 2 GBM corresponding to different concentrations used.
The prepared Macadamia based adsorbents were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), carbon, hydrogen, nitrogen and sulphur (CHNS) analysis, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) analysis. The determination of surface properties such as the point of zero charge (pHPZC), bulk density and the surface negative charge was accomplished with appropriate wet chemistry methods. The adsorption of selected trace metals (Cu(II), Cd(II), Co(II), and Cr(VI)) was done in batch experiments. Atomic absorption spectroscopy (AAS) was used for the determination of metal ions concentrations and total Cr. The ultraviolet-visible (UV–Vis) spectroscopy was used for the determination of Cr(VI) concentration remaining in solution after adsorption.
The RMN, AMM, and BMM adsorbents showed potential in removing more than 45% Cu(II) ions, but less than 30% for both Cd(II) and Co(II) ions. However, more than 90% removal of Cr(VI) ions was achieved with the same adsorbents. Consequently, only the adsorption of Cr(VI) was further investigated in the study due to the higher removal efficiency displayed by the Macadamia based biosorbents. The optimum adsorption conditions for the RMN, AMM, and BMM materials were found to be pH 2, 100 mg/L initial concentration of Cr(VI), 600 min contact time and 0.2 g adsorbent mass. The ideal conditions for the 0.5 GAM and 0.5 GBM were found to be pH 2, 25 mg/L initial concentration of Cr(VI), 180 min contact time, and 0.15 g adsorbent mass. The optimum temperature was found to be 40℃ for all materials. A volume of 20 mL was used for all batch experiments. The RMN, AMM, BMM, 0.5 GBM, and 0.5 GAM adsorption mechanisms were better described by the Langmuir isotherm which predicted a monolayer sorption process. The kinetic data fitted better to the pseudo second-order rate model which signified a chemisorption type of interaction. The thermodynamic parameters showed that the adsorption reaction was feasible, spontaneous and endothermic. The Macadamia based materials showed greater potential as adsorbents for the adsorption of Cr(VI) ions from aqueous solution compared to the other selected trace metal ions [Cd(II), Cu(II) and Co(II)].
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Desenvolvimento e aplicação de filmes à base de gelatina aditivados com extrato etanólico de cúrcuma (Cúrcuma longa L.) / Development and application of gelatin-based films added with curcuma ethanol extract (Curcuma longa L.)Bitencourt, Camila Marques 05 March 2013 (has links)
As embalagens ativas têm ganhado destaque no mercado mundial, pois possibilitam a interação do alimento com o material da embalagem, permitindo a incorporação de compostos ativos. Dentre os compostos ativos, o extrato etanólico de cúrcuma (EEC) tem chamado atenção, devido suas propriedades antioxidante, antimicrobiana, dentre outras. Assim, os objetivos deste trabalho foram desenvolvimento, caracterização e aplicação de filmes à base de gelatina aditivados com EEC. Os filmes foram produzidos pela técnica de casting (2 g de gelatina/100 g de solução filmogênica (SF), 30 g de sorbitol/100 g de gelatina) e o EEC foi incorporado na SF, nas concentrações de 0, 5, 50, 100, 150 e 200 g EEC/100 g de gelatina. Os filmes foram caracterizados em relação às propriedades mecânicas, conteúdo de água, matéria solúvel, permeabilidade ao vapor de água, parâmetros de cor, opacidade, brilho, microestrutura, espectroscopia de infravermelho com transformada de Fourier (FTIR), barreira UV/Vis, transparência, teor de curcumina, atividade antioxidante e atividade antimicrobiana. O filme com os melhores resultados para as propriedades mecânicas, barreira UV/Vis e atividade antioxidante foi utilizado para embalar noz macadâmia e, as propriedades da noz foram avaliadas em função do tempo de estocagem. A incorporação do EEC melhorou as propriedades mecânicas dos filmes, a tensão de ruptura aumentou de 27,7 MPa (filme controle) para 35,1 MPa (filme com 200 g de EEC/100 g de gelatina) e a elongação na ruptura aumentou de 22,3 % (filme controle) para 36,5 % (filme com 200 g de EEC/100 g de gelatina). O conteúdo de água não foi influenciado pela adição do EEC, porém a matéria solúvel reduziu em relação ao filme controle. A permeabilidade ao vapor de água também reduziu em média 24,1 % para os filmes aditivados. Os parâmetros de cor, opacidade e brilho foram afetados pela incorporação do EEC. As análises de microestrutura indicaram alterações na rugosidade da superfície e um aumento na rugosidade da estrutura interna, em função do aumento da concentração de EEC nos filmes. A análise de FTIR mostrou deslocame ntos dos picos associados às amidas A, I e II para os filmes aditivados. Os filmes com EEC apresentaram reduzida transmitância na região UV/Vis e aumento da transparência. O teor de curcumina aumentou linearmente (y=0,6115x+6,6629, R2=0,9817) com o aumento da concentração do extrato. A capacidade antioxidante aumentou em função do aumento da concentração do EEC e a atividade antimicrobiana (Staphylococcus aureus) foi verificada para concentrações acima de 5 g de EEC/100 g de gelatina. Assim, o filme com concentração de EEC de 200 g de EEC/100 g de gelatina foi utilizado para embalar noz macadâmia. Em relação ao conteúdo de água da noz macadâmia foram observadas diferenças significativas em função do tipo de filme utilizado (com e sem ad ição de EEC) nos primeiros 30 dias de estocagem. Entretanto, para a atividade de água não foram observadas diferenças. Após 60 dias a dureza da noz macadâmia embalada com o filme aditivado foi superior e as substâncias reativas (ácido tiobarbitúrico) fora m inferiores. Pode-se concluir que é possível a utilização desse sistema como embalagem ativa para a noz macadâmia. / Active packaging has been receiving growing attention in the world market because it allows interaction between food and packaging material, thus enabling the incorporation of active compounds. Among active compounds, curcuma ethanol extract (CEE) has been highlighted mainly because its antioxidant and antimicrobial properties. The objectives of this study were the development, characterization and application of gelatin-based films added with CEE. The films were produced by casting technique (2 g gelatin/100 g filmogenic solution (FS), 30 g sorbitol/100 g gelatin) and CEE was added to FS at 6 concentrations (0, 5, 50, 100, 150 and 200 g CEE/100 g gelatin). The films were characterized regarding mechanical properties, water content, soluble matter, water vapor permeability, color parameters, opacity, gloss, microstructure, Fourier transform infrared spectroscopy (FTIR), light transmission, transparency, curcumin content, antioxidant activity, and antimicrobial activity. The film with the best results concerning mechanical properties, light transmission and antioxidant activity was selected to package macadamia nut, whose properties were evaluated during the storage time. The addition of CEE improved mechanical properties of the films: tensile strength increased fro m 27.7 MPa (control film) to 35.1 MPa (film with 200 g CEE/100 g gelatin) and the elongation at break increased from 22.3 % (control film) to 36.5 % (film with 200 g CEE/100 g gelatin). Water content was not affected by the addition of CEE, however soluble matter reduced compared to control film. The water vapor permeability for added films also reduced on average 24.1 %. Color parameters, opacity and gloss were affected by the incorporation of CEE. Microstructure analysis indicated changes in surface roughness and increase in roughness regarding the internal structure due to the growing concentration of CEE in the films. FTIR analysis showed peaks displacements associated to amides A, I and II for the added films. Films added CEE showed reduced transmittance for the UV/Vis region and increased transparency. The curcumin content increased linearly (y=0.6115x+6.6629, R2=0.9817) with increasing extract concentration. The antioxidant capacity increased was improved with the increase of extract concentration and antimicrobial activity (Staphylococcus aureus) was verified at concentrations above 5g CEE/100g gelatin. Thus, the film with CEE concentration of 200 g CEE/100 g gelatin was used for macadamia nut packaging. Regarding water content in the macadamia nut, significant differences in the first 30 day of storage were found according to the film (with or without CEE). However, no significant difference concerning water activity was found. After 60 days of storage nuts packaged with added film had their hardness increased and lower reactive substances (thiobarbituric acid). It can be concluded that the utilization of this system as active packaging for macadamia nut is possible.
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Desenvolvimento e aplicação de filmes à base de gelatina aditivados com extrato etanólico de cúrcuma (Cúrcuma longa L.) / Development and application of gelatin-based films added with curcuma ethanol extract (Curcuma longa L.)Camila Marques Bitencourt 05 March 2013 (has links)
As embalagens ativas têm ganhado destaque no mercado mundial, pois possibilitam a interação do alimento com o material da embalagem, permitindo a incorporação de compostos ativos. Dentre os compostos ativos, o extrato etanólico de cúrcuma (EEC) tem chamado atenção, devido suas propriedades antioxidante, antimicrobiana, dentre outras. Assim, os objetivos deste trabalho foram desenvolvimento, caracterização e aplicação de filmes à base de gelatina aditivados com EEC. Os filmes foram produzidos pela técnica de casting (2 g de gelatina/100 g de solução filmogênica (SF), 30 g de sorbitol/100 g de gelatina) e o EEC foi incorporado na SF, nas concentrações de 0, 5, 50, 100, 150 e 200 g EEC/100 g de gelatina. Os filmes foram caracterizados em relação às propriedades mecânicas, conteúdo de água, matéria solúvel, permeabilidade ao vapor de água, parâmetros de cor, opacidade, brilho, microestrutura, espectroscopia de infravermelho com transformada de Fourier (FTIR), barreira UV/Vis, transparência, teor de curcumina, atividade antioxidante e atividade antimicrobiana. O filme com os melhores resultados para as propriedades mecânicas, barreira UV/Vis e atividade antioxidante foi utilizado para embalar noz macadâmia e, as propriedades da noz foram avaliadas em função do tempo de estocagem. A incorporação do EEC melhorou as propriedades mecânicas dos filmes, a tensão de ruptura aumentou de 27,7 MPa (filme controle) para 35,1 MPa (filme com 200 g de EEC/100 g de gelatina) e a elongação na ruptura aumentou de 22,3 % (filme controle) para 36,5 % (filme com 200 g de EEC/100 g de gelatina). O conteúdo de água não foi influenciado pela adição do EEC, porém a matéria solúvel reduziu em relação ao filme controle. A permeabilidade ao vapor de água também reduziu em média 24,1 % para os filmes aditivados. Os parâmetros de cor, opacidade e brilho foram afetados pela incorporação do EEC. As análises de microestrutura indicaram alterações na rugosidade da superfície e um aumento na rugosidade da estrutura interna, em função do aumento da concentração de EEC nos filmes. A análise de FTIR mostrou deslocame ntos dos picos associados às amidas A, I e II para os filmes aditivados. Os filmes com EEC apresentaram reduzida transmitância na região UV/Vis e aumento da transparência. O teor de curcumina aumentou linearmente (y=0,6115x+6,6629, R2=0,9817) com o aumento da concentração do extrato. A capacidade antioxidante aumentou em função do aumento da concentração do EEC e a atividade antimicrobiana (Staphylococcus aureus) foi verificada para concentrações acima de 5 g de EEC/100 g de gelatina. Assim, o filme com concentração de EEC de 200 g de EEC/100 g de gelatina foi utilizado para embalar noz macadâmia. Em relação ao conteúdo de água da noz macadâmia foram observadas diferenças significativas em função do tipo de filme utilizado (com e sem ad ição de EEC) nos primeiros 30 dias de estocagem. Entretanto, para a atividade de água não foram observadas diferenças. Após 60 dias a dureza da noz macadâmia embalada com o filme aditivado foi superior e as substâncias reativas (ácido tiobarbitúrico) fora m inferiores. Pode-se concluir que é possível a utilização desse sistema como embalagem ativa para a noz macadâmia. / Active packaging has been receiving growing attention in the world market because it allows interaction between food and packaging material, thus enabling the incorporation of active compounds. Among active compounds, curcuma ethanol extract (CEE) has been highlighted mainly because its antioxidant and antimicrobial properties. The objectives of this study were the development, characterization and application of gelatin-based films added with CEE. The films were produced by casting technique (2 g gelatin/100 g filmogenic solution (FS), 30 g sorbitol/100 g gelatin) and CEE was added to FS at 6 concentrations (0, 5, 50, 100, 150 and 200 g CEE/100 g gelatin). The films were characterized regarding mechanical properties, water content, soluble matter, water vapor permeability, color parameters, opacity, gloss, microstructure, Fourier transform infrared spectroscopy (FTIR), light transmission, transparency, curcumin content, antioxidant activity, and antimicrobial activity. The film with the best results concerning mechanical properties, light transmission and antioxidant activity was selected to package macadamia nut, whose properties were evaluated during the storage time. The addition of CEE improved mechanical properties of the films: tensile strength increased fro m 27.7 MPa (control film) to 35.1 MPa (film with 200 g CEE/100 g gelatin) and the elongation at break increased from 22.3 % (control film) to 36.5 % (film with 200 g CEE/100 g gelatin). Water content was not affected by the addition of CEE, however soluble matter reduced compared to control film. The water vapor permeability for added films also reduced on average 24.1 %. Color parameters, opacity and gloss were affected by the incorporation of CEE. Microstructure analysis indicated changes in surface roughness and increase in roughness regarding the internal structure due to the growing concentration of CEE in the films. FTIR analysis showed peaks displacements associated to amides A, I and II for the added films. Films added CEE showed reduced transmittance for the UV/Vis region and increased transparency. The curcumin content increased linearly (y=0.6115x+6.6629, R2=0.9817) with increasing extract concentration. The antioxidant capacity increased was improved with the increase of extract concentration and antimicrobial activity (Staphylococcus aureus) was verified at concentrations above 5g CEE/100g gelatin. Thus, the film with CEE concentration of 200 g CEE/100 g gelatin was used for macadamia nut packaging. Regarding water content in the macadamia nut, significant differences in the first 30 day of storage were found according to the film (with or without CEE). However, no significant difference concerning water activity was found. After 60 days of storage nuts packaged with added film had their hardness increased and lower reactive substances (thiobarbituric acid). It can be concluded that the utilization of this system as active packaging for macadamia nut is possible.
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Removal of selected chlorinated phenolic compounds from water sources in Vaal Triangle using HPLC, Macadamia nutshell activated carbon and solid phase extractionMachedi, Sechaba 12 1900 (has links)
M. Tech (Department of Chemistry, Faculty of Applied and Computer Sciences) Vaal University of Technology. / In this study, analytical method for determining the chlorinated phenols in water was developed using High Performance Liquid Chromatography. The following four compounds which are 2, 4, 6- Trichlorophenol (2, 4, 6 TCP), 3-chlorophenol (3CP), 2, 4- Dichlorophenol (2, 4 DCP) and 4-chloro-3-methylphenol (4C3MP) were identified and
quantified with a High Performance Liquid Chromatography (HPLC). The validation parameters tested were,: linearity, trueness, precision, detection limit of quantitation, sensitivity, specificity, selectivity. The linear calibration ranges of five standard solution from 1-10 ppm. The linearity ranges between 0.9298-0.9813. The activated carbon based on the waste macadamia nutshell activated carbon (MAC) was investigated for its potential uses as an adsorbent for chlorinated phenols removal and compared with grafted macadamia nutshell activated carbon (GMAC). The adsorbent was characterized with Fourier transform infrared spectrophotometer (FTIR), scanning electron microscope (SEM) and thermo gravimetric analysis (TGA). The parameters such as pH, temperature, contact time, concentration and adsorbent were investigated by adsorption technique. The strata C18E has been used before for the same reason and therefore the research was based on mimic the functional group of solid phase extraction (SPE) into macadamia activated carbon (MAC). The functional groups in SPE C18E are benzene and octadecyl. MAC was grafted with strata C18E functional groups to compare its potential with the SPE. The pseudo-first-order and pseudo-second-order kinetic models were applied to verify the experimental data. The pseudo-second order exhibited the best fit for the kinetic studies for MAC adsorption. Chemical removal of chlorinated phenols from wastewater is necessary to reduce harmful products on the environment and human health. Chlorinated phenols have been previously listed as some of the highest priority contaminants and as well as mainly important capability carcinogenic toxins released from chemical plants. Their availability in water supplies was perceived by their bad taste and smell. The acceptable chlorinated phenols concentration in portable water is 1 (mg/l) base on the approval of world health organization. The permanent checking of chlorinated phenols in environmental samples has a greater significance and stresses highly effectiveness, common selectively and great sensitively methods. The maximum uptake of Phenol using weighed mass of MAC was found to be 78 % and for GMAC was 84% for both 2,4,6TCP. t=250 min, pH=5, Co=1mg/l, T = 25 oC and m = 0.3 g/l were the optimum condition for Phenol-MAC system and GMAC system. Over all analysis of equilibrium model analysis indicates the fitness of Langmuir isotherm model to Phenol MAC adsorption system, suggesting a monolayer adsorption of phenol on the surface of MAC. Phenol adsorption capacity of MAC was found to be decreasing with increase in temperature suggesting that the adsorption process was exothermic in nature, which was further supported by the negative values of change in enthalpy. Characterization of MAC and GMAC confirmed the mesoporous texture, highly carbonaceous nature and a higher effective surface area of 912 m2/g. The highest phenol uptake capacity of GMAC was found to be 8.0049 mg/g. The optimal conditions for various process parameters are t = 250 min, pH=5, Co=1mg/l, T = 25 oC and m = 0.3 g/l were the optimum condition for Phenol-GMAC system. Like Phenol-MAC system, the kinetics studies confirmed that Phenol-GMAC adsorption system can be described by pseudo- second-order kinetics model. Equilibrium model analysis indicates the fitness of Langmuir isotherm model to Phenol-MAC adsorption system, suggesting a monolayer adsorption of phenol on the surface of GMAC. Phenol adsorption capacity of GMAC was found to be decreasing with increase in temperature suggesting that the adsorption process was exothermic in nature, which was further supported by the negative values of change in enthalpy. The negative values of Gibb’s free energy suggested that adsorption of phenol onto GMAC was a spontaneous process.
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Desenvolvimento e uso de marcadores SSR E DArT para estudos de diversidade genética em macadâmia (Macadamia integrifolia) / Development and use of SSR and DArT genetic markers to study genetic diversity in macadamia (Macadamia integrifolia)Sobierajski, Graciela da Rocha 24 May 2012 (has links)
A macadâmia (Macadamia integrifolia Maiden & Betche) é uma nogueira arbórea originária das florestas tropicais australianas. Sua distribuição natural ocorre por quase toda a costa leste da Austrália. No Brasil, foi introduzida em 1931, mas sua expansão aconteceu a partir da década de 70. As variedades comerciais são originadas de duas espécies, Macadamia integrifolia e M. tetraphylla, e seus híbridos. As informações sobre pedigree são geralmente incompletas e a identificação das variedades algumas vezes não é clara. O uso de técnicas moleculares auxilia em diversas fases dos programas de melhoramento, inclusive na caracterização do material genético e seleção de parentais envolvidos nos cruzamentos. A partir do uso de técnicas moleculares (microssatélites e diversity array technology), as 28 variedades que compõe o germoplasma brasileiro foram genotipadas com a finalidade de investigar a estrutura e a divergência genética entre estas. Foram utilizados 29 primers flanqueadores de locos microssatélites e 462 marcas de diversity array technology. A análise pelo programa Structure apresentou a formação de duas subpopulações: uma com a maioria das variedades desenvolvidas no Havaí/USA e Brasil, e outra composta pelas variedades desenvolvidas na Austrália e três variedades brasileiras. A análise da diversidade genética detectou valores medianos de heterozigosidade para o conjunto de variedades ( = 0,46 e = 0,43), com indicação de um pequeno excesso de homozigoto em relação ao esperado sob Equilíbrio de Hardy-Weinberg. A estimativa do índice de fixação (F = 0,067) para o conjunto de subpopulações apresentou grande variação, porém na média, foi baixo e não diferente de zero. Os resultados também mostram que a maior parte da diversidade genética do germoplasma está dentro de subpopulações ( q = 0,041). O índice de fixação devido ao sistema reprodutivo também variou entre os locos analisados, mas na média foi igualmente baixo e não diferente de zero ( f = 0,027). Os valores das Distâncias de Jaccard variaram entre 0,00 e 0,787 enquanto que as Distâncias de Roger Modificada variaram entre 0,227 e 0,671. O dendrograma UPGMA formado pelas Distâncias de Jaccard formou três grupos enquanto que pelas Distâncias de Roger Modificada formou dois grupos, sendo possível distinguir somente o grupo externo formado pelas duas espécies de grevílea. A falta de divergência entre alguns pares de variedades foi inesperada, assim como o não agrupamento entre variedades identificadas com o mesmo nome ou que apresentam histórico de parentesco. Da mesma forma, as duas subpopulações discriminadas pelo programa Structure não formaram agrupamento específico em ambos os dendrogramas. Os resultados das análises dos Componentes Principais foram coerentes aos obtidos nos dendrogramas formando os mesmos agrupamentos. / Macadamia (Macadamia integrifolia Maiden and Betche) is a nut crop tree widespread across eastern Australia. Although has been introduced in Brazil in 1931, just in the past 20 years its cultivated area has expanded more significantly. Commercial varieties are originated from Macadamia integrifolia and M. tetraphylla, as well as its hybrids. The information on pedigree is generally incomplete and the identification of varieties is sometimes not so clear. Molecular techniques could provide genetic information useful for breeding programs, such as, the kinship (relatedness) between individuals. Molecular techniques (microsatellites and diversity array technology) was used to genotype all 28 varieties that composes Brazils germoplasma with the purpose to investigate the structure and the genetic divergence between these varieties. Twenty nine microsatellites locus and 462 markers of diversity array was used. Analysis using the Structure software showed evidence of two subpopulations: one with the majority of the varieties developed in the Hawaii/USA and Brazil, and another with varieties developed in Australia and three in Brazil. The analysis of genetic diversity detected medium values of heterozigosis ( = 0.46 and = 0.43), with indication of a small excess of homozygotes in relation the expected value under Hardy- Weinberg equilibrium. The estimate of inbreeding coefficient showed great variation (from - 0.522 to 0.558), however in the average (F = 0.067) it was low and statistically not different from zero. The results also showed that most of the genetic diversity is within subpopulations ( q = 0.041). The inbreeding due to the reproductive system varied between analyzed loci, but on average it was low and statistically not different from zero ( f = 0.027). Values of Jaccard distances ranged from 0 to 0.787, whereas the modified Rogers distances ranged from 0.227 to 0.671. UPGMA Cluster analysis from Jaccard distances formed three groups, whereas modified Rogers distances of formed two groups. In the latter, it is possible to distinguish only the external group formed by the two species from Grevilea spp. For some varieties that we expected to be clustered together were unexpected assigned to different clusters. On the other hand, for some varieties that we expected to be placed in different clusters were unexpected clustered together. Unexpected, the two subpopulations discriminated in the analysis (Structure) did not form specific groups when using both Jaccard and modified Rogers distances. The results of Principal Coordinate Analysis were coherent with the UPGMA analyses.
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