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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fluorescence huminových kyselin 3D excitačně emisní metodou. / Fluorescence spectroscopy of humic acids by excitation-emission matrix.

Mlčoch, Tomáš January 2008 (has links)
The aim of the diploma thesis was measurement and characterization of EEM (excitation emisssion spectra) of IHSS humic acids standards and soil, lignite humic and fulvic acids and humates prepared from different sources. The aim was to follow the differences in their fluorescence spectra and to determine precise location of fluorescence peaks. Target of this work was to find the optimal way for exporting of scan data to the 3D EEM spectrofluorographs. The dependence of relative intensity of fluorescence on pH value was studied further.
2

Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical composting

Forgerini, Daniely 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo&reg. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo&reg. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
3

Reguladores de crescimento e adubação orgânica no estresse hídrico da cana-planta / Growth regulators and organic fertilization in the water stress of sugarcane

Malvestitti Neto, Antonio 04 October 2018 (has links)
No presente trabalho, objetivou-se estudar o uso de biorregulador sintético, cama de frango e torta de filtro no desenvolvimento e produtividade da cana-de-açúcar em situação de estresse hídrico. O experimento foi implantado e conduzido no município de Analândia/SP. O delineamento experimental utilizado foi o de blocos ao acaso, com 9 tratamentos, distribuídos aletoriamente em 5 Repetições, totalizando 45 parcelas. O biorregulador utilizado é constituído de três grupos químicos de hormônios sintéticos: auxina (0,005%), giberilina (0,005%) e cinetina (0,009%), e os tratamentos foram: 1 controle sem biorregulador, 2 biorregulador no plantio, 3 biorregulador no rebaixamento da entrelinha, 4 biorregulador no crescimento final, 5 biorregulador no plantio e crescimento final, 6 biorregulador no plantio e rebaixamento da entrelinha, 7 biorregulador no rebaixamento da entrelinha e crescimento final, 8 torta de filtro sem biorregulador, 9 cama de frango sem aplicação biorregulador. O tratamento Stimulate aplicado no sulco de plantio, apresentou a maior produtividade, com 129,93 t ha-1. Os tratamentos cama de frango e torta de filtro não se diferenciaram dos demais em produtividade. A aplicação de Stimulate e compostos orgânicos não interfiriram nos parâmetros tecnológicos. A utilização do regulador de crescimento mostrou-se eficiente. / In the present work, the objective was to study the use of synthetic biorregador, litter of chicken and filter cake in the development and productivity of sugarcane in a situation of water stress. The experiment was implemented and conducted in the city of Analândia / SP. The experimental design was used for the use of blocks, with 9 treatments, distributed in 5 replications, totaling 45 plots. The bioregulator used consisted of three chemical groups of synthetic hormones: auxin (0.005%), giberilin (0.005%) and kinetin (0.009%), and treatments were: 1 control without bioregulator, 2 bioregulator at planting, 3 bioregulator lowering of the interweave, 4 bioregulator in the final growth, 5 bioregulator in the planting and final growth, 6 bioregulator in the planting and lowering of the interweave, 7 bioregulator in the lowering of the interweave and final growth, 8 filter cake without bioregulator, 9 chicken bed without bioregulator application. The Stimulate treatment applied in the planting groove, presented higher productivity, with 129.93 t ha-1. The chicken bed and filter cake treatments did not differ from the others in productivity. The application of Stimulate and compound vegetables in interfered in the technological parameters. The use of growth regulator was eficiente.
4

Reguladores de crescimento e adubação orgânica no estresse hídrico da cana-planta / Growth regulators and organic fertilization in the water stress of sugarcane

Antonio Malvestitti Neto 04 October 2018 (has links)
No presente trabalho, objetivou-se estudar o uso de biorregulador sintético, cama de frango e torta de filtro no desenvolvimento e produtividade da cana-de-açúcar em situação de estresse hídrico. O experimento foi implantado e conduzido no município de Analândia/SP. O delineamento experimental utilizado foi o de blocos ao acaso, com 9 tratamentos, distribuídos aletoriamente em 5 Repetições, totalizando 45 parcelas. O biorregulador utilizado é constituído de três grupos químicos de hormônios sintéticos: auxina (0,005%), giberilina (0,005%) e cinetina (0,009%), e os tratamentos foram: 1 controle sem biorregulador, 2 biorregulador no plantio, 3 biorregulador no rebaixamento da entrelinha, 4 biorregulador no crescimento final, 5 biorregulador no plantio e crescimento final, 6 biorregulador no plantio e rebaixamento da entrelinha, 7 biorregulador no rebaixamento da entrelinha e crescimento final, 8 torta de filtro sem biorregulador, 9 cama de frango sem aplicação biorregulador. O tratamento Stimulate aplicado no sulco de plantio, apresentou a maior produtividade, com 129,93 t ha-1. Os tratamentos cama de frango e torta de filtro não se diferenciaram dos demais em produtividade. A aplicação de Stimulate e compostos orgânicos não interfiriram nos parâmetros tecnológicos. A utilização do regulador de crescimento mostrou-se eficiente. / In the present work, the objective was to study the use of synthetic biorregador, litter of chicken and filter cake in the development and productivity of sugarcane in a situation of water stress. The experiment was implemented and conducted in the city of Analândia / SP. The experimental design was used for the use of blocks, with 9 treatments, distributed in 5 replications, totaling 45 plots. The bioregulator used consisted of three chemical groups of synthetic hormones: auxin (0.005%), giberilin (0.005%) and kinetin (0.009%), and treatments were: 1 control without bioregulator, 2 bioregulator at planting, 3 bioregulator lowering of the interweave, 4 bioregulator in the final growth, 5 bioregulator in the planting and final growth, 6 bioregulator in the planting and lowering of the interweave, 7 bioregulator in the lowering of the interweave and final growth, 8 filter cake without bioregulator, 9 chicken bed without bioregulator application. The Stimulate treatment applied in the planting groove, presented higher productivity, with 129.93 t ha-1. The chicken bed and filter cake treatments did not differ from the others in productivity. The application of Stimulate and compound vegetables in interfered in the technological parameters. The use of growth regulator was eficiente.
5

Obtenção e caracterização de biofertilizantes a partir de técnicas de compostagem sólida / Production and characterization of biofertilizers from solid technical composting

Daniely Forgerini 16 March 2012 (has links)
A matéria orgânica (MO) encontrada no solo pode ser dividida em dois compartimentos, o primeiro é composto pela fração não humificada, representada pelos compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas) e o segundo é formado pelas substâncias húmicas (SH), produtos da intensa transformação dos resíduos orgânicos pela biomassa e polimerização dos compostos orgânicos. A MO funciona como um reservatório de nutrientes do solo, sendo então responsável pela fertilidade deste. O cultivo intensivo tende a reduzir a quantidade de MO. A utilização de fertilizantes orgânicos, também chamados de biofertilizantes, é considerada uma alternativa sustentável de recuperar a fertilidade do solo, pois além de repor adequadamente os nutrientes perdidos ainda reutiliza resíduos orgânicos que se dispensados na natureza causariam impactos ambientais negativos. Neste trabalho foram obtidos dois biofertilizantes de esterco bovino, utilizando os processos de vermicompostagem e o de compostagem sólida acrescentada de microrganismos provenientes do produto comercial denominado Microgeo&reg. Para fins de caracterização e comparação, foram realizadas análises físico-químicas nesses biofertilizantes, cujos resultados demonstraram que ambos se encontram dentro dos parâmetros estabelecidos pelo Ministério de Agricultura Pecuária e Abastecimento (MAPA), para a comercialização de fertilizantes orgânicos e que houve uma maior incorporação de nutrientes no esterco após a realização dos dois processos. Para a determinação do grau de humificação dos biofertilizantes, foram utilizadas as técnicas de espectroscopia de fotoacústica e ultravioleta - visível, que apresentaram a mesma tendência de absorção, tendo absorção máxima, próximo a 300nm, e a técnica de espectroscopia de infravermelho que apresentou bandas de absorção tipicamente encontradas em estruturas de ácidos húmicos, para ambos os biofertilizantes. Foram realizados também, testes de germinação com os biofertilizantes obtidos, utilizando sementes de alface, que apresentaram boa germinação e bom crescimento de biomassa para os dois biofertilizantes. Concluiu-se então com este trabalho que os dois produtos obtidos apresentam características similares e podem ser utilizados com eficiência na recuperação da fertilidade de solos. / The organic matter (OM) in the soil can be divided into two compartments. The first is composed of non humified fraction, represented by the organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins) and the second compartment is formed by humic substances, which are products of intense transformation of the organic matter and biomass by polymerization of the organic compounds. The OM acts as a reservoir of soil nutrients and it is responsible for soil fertility. The intensive agriculture tends to reduce this amount of OM. The use of organic fertilizers, also called biofertilizers, is considered a sustainable alternative to restore soil fertility, as well as restore lost nutrients properly by reusing organic waste which if released in the environment could cause negative environmental impacts. In this work two biofertilizers were obtained from cattle manure, using the vermicomposting and solid composting processes. In the solid composting process it was added microorganisms from the commercial product called Microgeo&reg. For purposes of characterization and comparison, physical-chemical analysis were performed in these biofertilizers, showing that both are within the parameters established by the Ministry of Agriculture Livestock and Supply, for the marketing of organic fertilizers and a greater incorporation of nutrients in the cattle manure after the completion of the two processes occurs. To determine the degrees of humification of the produced biofertilizers both photoacoustic and ultraviolet - visible spectroscopic techniques were used, showing the same trend of absorption and maximum absorption near 300 nm. The infrared spectroscopy which showed absorption bands typically found in structures of humic acids for both fertilizers was also used. The germination tests were performed using lettuce seeds planted in soil mixed with the biofertilizers. The results pointed out to a good germination and growth of biomass for two biofertilizers. The conclusion of this work was that both biofertilizers have similar characteristics and both can be used effectively in the recovery of soil fertility.
6

Especiação de chumbo e cádmio: desenvolvimento de métodos eletroanalíticos para a avaliação da influência da matéria orgânica natural e substâncias húmicas / Speciation of lead and cadmium: development of electroanalytical methods to evaluate the influence of natural organic matter and humic substances

Monteiro, Adnívia Santos Costa [UNESP] 07 April 2017 (has links)
Submitted by ADNIVIA SANTOS COSTA MONTEIRO null (adniviacosta@hotmail.com) on 2017-05-02T16:46:03Z No. of bitstreams: 1 Tese Adnívia S. C. Monteiro.pdf: 2683414 bytes, checksum: 3838428f87bcd749eeed2b8e389be1f3 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-03T20:31:20Z (GMT) No. of bitstreams: 1 monteiro_asc_dr_araiq.pdf: 2683414 bytes, checksum: 3838428f87bcd749eeed2b8e389be1f3 (MD5) / Made available in DSpace on 2017-05-03T20:31:20Z (GMT). No. of bitstreams: 1 monteiro_asc_dr_araiq.pdf: 2683414 bytes, checksum: 3838428f87bcd749eeed2b8e389be1f3 (MD5) Previous issue date: 2017-04-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os estudos de especiação em águas naturais são a chave para a compreensão do comportamento e destino dos íons metálicos no ambiente, uma vez que estes elementos podem ser encontrados em diversas formas químicas (livres ou complexados). A mobilidade, biodisponibilidade e transporte desses íons podem ser influenciados pela presença da matéria orgânica natural (MON) e as substâncias húmicas aquáticas (SHA), principais ligantes presente no ambiente aquático. Nesse contexto, o objetivo desse trabalho foi desenvolver métodos eletroanalíticos utilizando a cronopotenciometria de redissolução anódica (SCP) e a técnica de redissolução nernstiana na ausência de gradientes (AGNES) capazes de determinar a concentração de cádmio total (CdT) e livre (CdL), respectivamente, diretamente em amostras de águas dos rios Itapanhaú (RI) e Sorocabinha (RS) localizados no estado de São Paulo, que possibilitem uma futura aplicação on-site. E avaliar a influência da MON e SHA extraídas desses rios nas interações com o Cd(II) e/ou Pb(II). Para investigar o efeito da sazonalidade foram coletadas amostras de água no março e novembro de 2014, as quais foram caracterizadas através de parâmetros de qualidade da água, carbono orgânico dissolvido (COD), espectroscopia UV/Vis e concentrações de metal total, dissolvido e “livre” (ultrafiltrado em 1kDa com fluxo tangencial - UFT). As SHA e suas frações (ácido húmico (AH) e fúlvico (AF) foram caracterizadas por meio da análise elementar, RMN 13C e fracionadas através da UFT com membranas de 100, 30,10, 3 e 1 kDa. Os métodos desenvolvidos de SCP (determinação do CdT) e de AGNES (determinação do CdL) aplicados nas amostras de águas in natura e ultrafiltradas em 1kDa, foram validados por comparação com a espectroscopia de absorção atômica com atomização em forno de grafite (GF-AAS). Os resultados encontrados revelaram que as principais diferenças entre as águas dos RI e RS estão associadas possivelmente à maior influência da água do mar e da sazonalidade no RS. A composição estrutural das SHA e AF apresentou maior predominância de compostos alifáticos. A distribuição do COD após o fracionamento molecular mostrou que as frações predominantes nas SHA e AF estiveram entre 10 e 1 kDa, enquanto que para os AH, 50% do COD é maior que 100kDa. Os resultados de SCP (LD de 1,6x10-9 mol L-1) e AGNES (LD de 1,9x10-9 mol L-1) revelaram o seu potencial na quantificação do Cd(II) total e livre, respectivamente, nas amostras estudadas. Os estudos da interação de Cd(II) e Pb(II) com os AF e AH revelaram que ambos os materiais dos RI e RS apresentaram maior complexação com Pb(II), e a complexação aumenta com o aumento do pH. / The study of speciation in natural waters are crucial to understand the behaviour and fate of metal ions in the environment, since these elements can be found in different chemical forms (complexed or free). The mobility, bioavailability and transport of these ions can be influenced by natural organic matter (NOM) and aquatic humic substances (AHS), which are the main ligands in aquatic environments. The objective of this thesis was to develop electroanalytical methods using the techniques stripping chronopotenciometry (SCP) and absence of gradients and nernstian stripping (AGNES), which are able to determine the concentration of total (TCd) and free (FCd) cadmium directly in water samples from the rivers Itapanhaú (RI) and Sorocabinha (RS), located in the state of São Paulo. It would make possible a future on-site measurement applications. This study also aimed to evaluate the influence of NOM and AHS extracted from these rivers in the interactions with Cd(II) and Pb(II). Water samples were taken in march and november/2014 in order to investigate the effect of seasonality. These samples were characterised using water quality parameters, dissolved organic carbon (DOC), UV/VIS spectroscopy and concentrations of total, dissolved and free metal (ultrafiltered through 1 kDa membrane with tangential flow- TUF). AHS and their fractions (humic, HA, and fluvic acid, FA) were characterised by elemental analysis, NMR 13C. They were fractionated through TUF through membranes 100, 30, 10, 3 and 1 kDa. The methods developed of SCP (TCd determination) and AGNES (CdL determination) applied in the in natura and ultrafiltered (1 kDa) samples were validated using graphite furnace atomic absorption spectrometry (GFAAS). The results showed that the main differences between the waters from RI and RS are related probably to the influence of seawater and seasonality. The structural composition of AHS and FA presented higher content of aliphatic compounds. The distribution of DOC after size fractionation showed that the predominant fractions in the AHS and FA were between 10 and 1 kDa. On the other hand, 50% of the material was higher than 100 kDa in the HA. The results of SCP (LoD: 1.6x10-9 mol L-1) and AGNES (LoD: 1.9x10-9 mol L-1) revealed their potential in quantification of total and free Cd(II), respectively, in the samples analysed. The study of interactions of Cd(II) and Pb(II) with FA and HA showed that both materials from RI and RS presented higher complexation with Pb(II). The complexation increases with the pH for both materials. / FAPESP: 13/14122-0
7

Chování huminových kyselin ve vodných roztocích / Behaviour of humic acids in aqueous solutions

Čechová, Eva January 2008 (has links)
Tato práce se zabývá chováním huminových kyselin ve vodných roztocích a to především jejich disociací a rozpustností. Disociace huminových kyselin byla studovaná jejich částečným rozpuštěním ve vodě a v roztocích solí o různých iontových silách. Analyzované huminové kyseliny pocházely jak z lignitických tak i půdních zdrojů a jedna z nich byla upravena plazmatem. Metodami použitými při experimentech byla potenciometrie, konduktomerie a UV/VIS spektroskopie. Podle Henderson-Hasselbalchovy závislosti byly vypočítány zdánlivé disociační konstanty. Dále byly určeny zdánlivé aktivitní koeficienty kyselých funkčních skupin. Poté byla studovaná rozpustnost huminových kyselin ve vodných roztocích solí. Byly sestrojeny závislosti pH hodnot, vodivostí a absorbancí jak na obsahu huminových kyselin ve vzorku tak na iontové síle roztoku. Studována byla také kinetika disociace huminových kyselin. Získaná data byla srovnána s navrženou hypotézou předpokládající několikakrokový mechanismus disociace huminových kyselin. Chovaní všech vzorků huminových kyselin odpovídalo navrženému mechanismu. Bylo potvrzeno, že stupeň disociace huminových kyselin ve vodných roztocích klesá s rostoucím obsahem huminové kyseliny stejně tak jako ve vodných roztocích solí s rostoucí iontovou silou.
8

Sledování komplexace mědi s huminovými kyselinami fluorescenční metodou / Following of cooper complexation with humic acids by fluorescence method

Hladík, Tomáš January 2009 (has links)
Humic acids have high ability to form stable complexes with copper ions, which influences their toxicity in environment. Fluorescent properties of sodium salt of humic acid, humate, isolated from South Moravian lignite, and its complexation behaviour with copper ions were investigated using emission, excitation and synchronous fluorescence spectroscopy. Both fluorescence emission and synchronous fluorescence spectra showed that humate form complex with copper since fluorescence intensity was quenched upon addition of copper ions to the humate samples. The aim of the diploma thesis was to found applicable ion concentration to observation fluorescence quenching and to determine the main fluorophore, which is affected by complexation through the use of synchronous fluorescence spectroscopy.
9

Využití chronopotenciometrické titrace v huminovém výzkumu / Utilization of chronopotentiometric titration in humic research

Viktorinová, Jana January 2013 (has links)
Humic acids are natural substances belonging to the group of humic substances. They arise mainly decomposition of plant residues. They are contained in soils, peat, sediments, young coal, water and even in the air. Humic acids are only partially soluble in water with increasing pH increases their solubility. Diploma thesis focuses on the use of chronopotentiometric titration of humic research. This method is mainly used for the determination of trace concentrations of analytes. This work is focused on the determination of acidity by potentiometric titration and the determination of dissociation constants using chronopotentiometry with measurement of pH of prepared samples.
10

Využití mikroenkapsulace při vývoji hydrogelových nosičových systémů / Application of microencapsulation techniques in development of novel controlled-release systems.

Karásková, Iva January 2017 (has links)
This diploma thesis deals with application of microencapsulation techniques in development of hydrogel controlled-release systems in which the main role is played by humic acids, biopolymer chitosan, compound fertilizer NPK and 3-indoleacetic acid. This paper continues my bachelor thesis topic about utilization of polyelectrolyte complexes. The aim of this work was to develop a literature review focusing on the microencapsulation techniques and according to its results optimize the method. Microencapsulation was performed with a commercial encapsulator BUSCHI B-395 Pro and a release of individual components into a water was measured. An amout of released substances was measured by UV-VIS method and HPLC analysis. Practical part also included testing of repeated swelling and drying. It was found that suitable composition and combination of ingredients form hydrogels for further use in agriculture.

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