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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

The competive strength of Moso Bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) in the natural mixed evergreen broad-leaved forests of the Fujian Province, China /

Fu, Jinhe, January 2001 (has links)
Zugl.: Göttingen, University, Diss., 2001.
2

Avaliação do potencial energético da biomassa de duas espécies de bambu cultivadas em Santa Catarina / Potential assesment of biomass energy two bamboo crops in Santa Catarina

Balduino Junior, Ailton Leonel 10 February 2016 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-06T15:51:14Z No. of bitstreams: 1 PGEF15MA054.pdf: 1294038 bytes, checksum: fababdbd931875c25f9cf6033b6c6963 (MD5) / Made available in DSpace on 2017-12-06T15:51:14Z (GMT). No. of bitstreams: 1 PGEF15MA054.pdf: 1294038 bytes, checksum: fababdbd931875c25f9cf6033b6c6963 (MD5) Previous issue date: 2016-02-10 / The aim of this study was to evaluate the energy potential of biomass of two species of bamboo from briquettes, coal and culms in natura. The species analyzed were: Bambusa vulgaris and Phyllostachys bambusoides with three years old. selected were 5.0 individuals of each species and collected portions of 1.0 m to 1.5 m long at the base, middle and top of the stems. The Bambusa vulgaris was collected at the Experimental Farm Ressacada the Federal University of Santa Catarina, Florianópolis, SC. The Phyllostachys bambusoides was collected in Fomio Honda property in Frei Rogério - SC. In culms in natura we were determined moisture content properties (TU); Basic density (DB); particle size (L); power higher calorific (PCS); immediate analysis (AI) and chemical composition (AQ). The bamboo was carbonized in the laboratory, and coal was analyzed for gravimetric yield (RG); moisture content (TU), bulk density (DA); power higher calorific (PCS) and immediate analysis (AI). The briquettes were made in hydraulic briquetter laboratory and analyzed properties were apparent density (AD) and compressive strength (RC). With the results we calculated the energy density (DE) for each product type and compared the best way to use species for the generation of energy. The culms of Bambusa vulgaris and Phyllostachys bambusoides had TU 39% and 36 %; DB 0.624 and 0.719 g / cm3 ; volatile content (TV ) of of 82.25% and 81.88%; fixed carbon (FC) 15.26% and 17.28%; ash content (CT) 2.49% 0 and 90%; and PCS 4571 and 4694 kcal / kg, respectively. The extractives content was 16.26% and 16.24% and the lignin content of 25.76% and 25.54, respectively. Charcoal had RG 36.40% and 33.35%; DA 0.372 and 0.367 g / cm³; TV 27.55% and 27.26%; CF of 67.32% and 31.09%; CT 5.12% and 1.65%, and PCS 7431 and 7587 kcal / kg, respectively. The briquettes were DA 1111 and 1170 kg / m³, and RC 4,961 and 4,677 MPa respectively. DE The culms was 11.91 and 14.14 MJ / m³. For coal of 11.60 and 11.66 MJ / m³, and the briquettes 21.31 and 22.99 MJ / m³, respectively. Bamboo species have similar quality for power generation. The species Phyllostachys bambusoides proved better than Bambusa vulgaris species in use in natura. Increased energy efficiency bamboo use was in the form of briquettes, followed by the use in nature, and later in the form of charcoal / O objetivo deste estudo foi avaliar o potencial energético da biomassa de duas espécies de bambu a partir de briquetes, carvão e colmos in natura. As espécies analisadas foram: Bambusa vulgaris e Phyllostachys bambusoides, com três anos de idade. Foram selecionados 5,0 indivíduos de cada espécie e coletadas porções de 1,0 m a 1,5 m de comprimento na base, no meio e no topo dos colmos. O Bambusa vulgaris foi coletado na Fazenda Experimental Ressacada da Universidade Federal de Santa Catarina, em Florianópolis, SC. O Phyllostachys bambusoides foi coletado na propriedade de Fomio Honda, em Frei Rogério – SC. Nos colmos in natura foram determinadas as propriedades de teor de umidade (TU); densidade básica (DB); granulometria (G); poder calorífico superior (PCS); análise imediata (AI) e composição química (AQ). O bambu foi carbonizado em laboratório, e o carvão foi analisado quanto ao rendimento gravimétrico (RG); teor de umidade (TU), densidade aparente (DA); poder calorífico superior (PCS) e análise imediata (AI). Os briquetes foram confeccionados em briquetadeira hidráulica de laboratório, e as propriedades analisadas foram: densidade aparente (DA) e resistência à compressão (RC). Com os resultados obtidos foi calculada a densidade energética (DE) para cada tipo de produto e comparada a melhor forma de utilização das espécies para a geração de energia. Os colmos de Bambusa vulgaris e Phyllostachys bambusoides tiveram TU de 39%, e 36%; DB de 0,624, e 0,719 g/cm3; teor de voláteis (TV) de 82,25%, e 81,88%; teor de carbono fixo (CF) de 15,26% e 17,28%; teor de cinzas (TC) de 2,49% e 0 90%; e PCS de 4571 e 4694 kcal/kg, respectivamente. O teor de extrativos totais foi de 16,26% e 16,24% e o teor de lignina de 25,76% e 25.54, respectivamente. O carvão vegetal teve RG de 36,40% e 33,35%; DA de 0,372 e 0,367 g/cm³; TV de 27,55% e 27,26%; CF de 67,32% e 31,09%; TC de 5,12% e 1,65% e PCS de 7431 e 7587 kcal/Kg, respectivamente. Os briquetes tiveram DA de 1111 e 1170 kg/m³, e RC 4,961 e 4,677 Mpa, respectivamente. A DE do colmos foi de 11,91 e 14,14 MJ/m³; para o carvão de 11,60 e 11,66 MJ/m³, e para os briquetes de 21,31 e 22,99 MJ/m³, respectivamente. As espécies de bambu possuem qualidade similar para geração de energia. A espécie Phyllostachys bambusoides mostrou-se melhor que a espécie Bambusa vulgaris no uso in natura. A maior eficiência energética do uso do bambu foi na forma de briquete, seguido do uso in natura, e posteriormente na forma de carvão vegetal
3

[en] INFLUENCE OF HORNIFICATION ON THE PHYSICAL AND FLEXURAL PROPERTIES OF MOSO BAMBOO / [pt] INFLUÊNCIA DA HORNIFICAÇÃO SOBRE AS PROPRIEDADES FÍSICAS E DE FLEXÃO DO BAMBU MOSO

SILIANI CORADINI GASPARINI CID 23 June 2020 (has links)
[pt] O bambu é um recurso natural, típico de regiões tropicais e subtropicais, cujas fibras vêm atraindo interesse para reforço de materiais compósitos, pelas suas excelentes propriedades mecânicas. Entretanto, como toda fibra vegetal, as fibras de bambu apresentam alto grau de higroscopicidade, inchando quando da presença de água, limitando seu uso devido à perda de durabilidade. Dessa forma, este trabalho visa estudar melhorias nas propriedades de flexão do bambu através do processo de hornificação por ciclos de molhagem e secagem, tratamento muito utilizado em polpas de madeira ou papel, que leva a reduções na capacidade de absorção e retenção de água das fibras, reduzindo seus poros e tornando sua estrutura mais enrijecida. Para isso foram investigados os efeitos de 3, 5 e 10 ciclos de molhagem e secagem sobre as propriedades físicas e comportamento mecânico (flexão e módulo de elasticidade) do bambu da espécie Moso (Phyllostachys pubescens). Com relação às propriedades físicas foram avaliadas as variações na capacidade de absorção e retenção de água do bambu ao longo dos ciclos, incluindo avaliação das variações dimensionais dos feixes vasculares ao final dos ciclos, realizada por meio de análise e processamento de imagens obtidas por microscópio estereoscópico. Ademais, o comportamento à flexão foi estudado por meio de ensaios de flexão a quatro pontos, avaliando possíveis melhorias na resistência à flexão, deflexão e módulo de elasticidade do bambu após os ciclos de molhagem e secagem, incluindo análise da influência do cisalhamento na flexão. As análises físicas demonstraram que com os ciclos ocorreu redução na capacidade de retenção de água do bambu, além de reduções na área superficial de seus feixes de fibras. Na flexão houve ganho de rigidez após os ciclos, chegando a aumentar em 70 por cento o módulo de elasticidade. / [en] Bamboo is a natural resource, typical of tropical and subtropical regions, whose fibers are attracting interest to reinforce composite materials, due to its excellent mechanical properties. However, like all plant fibers, bamboo fibers present a high degree of hygroscopicity, swelling when water is present, limiting its use due to loss of durability. Thus, this work aims to study improvements in the flexural properties of bamboo through the process of hornification by wetting and drying cycles, a treatment that is widely used in pulps of wood or paper, leading to reductions in the water absorption and retention capacity of the fibers, reducing its pores and making its structure stiffer. The effects of 3, 5 and 10 wetting and drying cycles on the physical properties and mechanical behavior (flexure and modulus of elasticity) of the Moso bamboo species (Phyllostachys pubescens) were investigated. Regarding the physical properties, the variations in the bamboo water absorption and retention capacity were evaluated along the cycles, including evaluation of the dimensional variations of the vascular bundles at the end of the cycles, performed by means of analysis and processing of images obtained by a stereoscopic microscope. In addition, the flexural behavior was studied by means of four-point flexural tests, evaluating possible improvements in flexural strength, deflection and modulus of elasticity of the bamboo after the wetting and drying cycles, including analysis of the influence of shear on flexion. The physical analyzes showed that with the cycles there was a reduction in the water retention capacity of bamboo, as well as reductions in the surface area of its fiber bundles. In flexion, there was a gain of stiffness after the cycles, increasing the modulus of elasticity by 70 per cent.
4

Adsorção de atrazina em biocarvões obtidos a partir de colmo de bambu / Adsorption of atrazine in biochar obtained from bamboo culm

Sbizzaro, Mariana 12 February 2016 (has links)
Made available in DSpace on 2017-07-10T19:24:24Z (GMT). No. of bitstreams: 1 Mariana_ sbizzaro.pdf: 1501907 bytes, checksum: 5610159e30f98d52848320f90146f751 (MD5) Previous issue date: 2016-02-12 / The agricultural sector has great influence in Brazilian economy. Furthermore, agricultural yield has been associated with pesticides application during crop cycle, which atrazine is applied for example, since it can cause environmental contamination when it does not reach its target. Thus, there are some essential and imperative options that can minimize contamination and negative impacts during agricultural practices. So, present study aimed at evaluating the ability of three biochars in atrazine adsorption. Therefore, three biochars produced from bamboo culm were used, whose species is Phyllostachys aurea, and temperature ranged at 350 ºC, 450 ºC and 550 ºC. The three studied biochars were named as BE350, BE450 and BE550. They were characterized based on their physical and chemical properties by elemental analysis, characterization of functional groups (Infrared Spectroscopy Fourier Transform - FTIR), surfaces morphology evaluation (Scanning Electron Microscopy - SEM) as well as specific surface area (ASEBET) and porosity. A kinetic study was carried out to determine the equilibrium period of adsorption process and the kinetic mechanism that controls such process. Langmuir and Freundlich isotherms were also modeled during this trial. Atrazine determination, after the adsorption test, was carried out by High Performance Liquid Chromatography (HPLC). The obtained analyses showed that the adsorption capacity of biochars decreased in the following order: BE 450> BE 350 > BE 550, and such capacity has been associated with the physical and chemical characteristics of biochars. The three studied biochars are well represented by the kinetic model of pseudo-second order. At last, all biochars have shown high affinity to adsorb atrazine; however, the biochar that was produced at 450 ºC has shown the highest adsorption capacity. / O setor agrícola possui grande destaque na economia brasileira, a produção agrícola está associada ao uso de pesticidas durante o ciclo das culturas, como é o caso da atrazina, que pode causar a contaminação do ambiente, quando não atinge seu alvo. Sendo assim, alternativas que minimizem as contaminações e impactos negativos da prática agrícola são essenciais e urgentes. Desta forma, o presente estudo teve por objetivo avaliar a capacidade de três biocarvões, em adsorver o herbicida atrazina. Para tanto, foram utilizados três biocarvões, produzidos a partir do colmo de bambu, da espécie Phyllostachys aurea à 350ºC, 450ºC e 550ºC, nomeados BE350, BE450 e BE550. Os biocarvões foram caracterizados quanto as propriedades físicas e químicas, por meio de análise elementar, caracterização de grupos funcionais (Espectroscopia de Infravermelho com Transformada de Fourier - FTIR), avaliação da morfologia das superfícies (Microscopia Eletrônica de Varredura - MEV), bem como, área superficial específica (ASEBET) e porosidade. Estudo cinético foi realizado, visando determinar o tempo de equilíbrio do processo de adsorção, bem como, o mecanismo cinético que controla o processo. Também foram modeladas isotermas de Langmuir e Freundlich. A determinação da atrazina, após os ensaios de adsorção, foi realizada por Cromatografia Líquida de Alta Performance (CLAE). As análises realizadas apontaram que a capacidade de adsorção dos biocarvões diminuiu na ordem de BE 450 > BE 350 > BE 550, e tal capacidade está associada às características físicas e químicas dos biocarvões. Os três biocarvões são bem representados pelo modelo cinético de pseudo-segunda ordem. Todos biocarvões exibiram elevada afinidade para a adsorção do herbicida atrazina, contudo, o biocarvão produzido à 450 ºC demonstra maior capacidade de adsorção
5

Adsorção de atrazina em biocarvões obtidos a partir de colmo de bambu / Adsorption of atrazine in biochar obtained from bamboo culm

Sbizzaro, Mariana 12 February 2016 (has links)
Made available in DSpace on 2017-05-12T14:47:40Z (GMT). No. of bitstreams: 1 Mariana_ sbizzaro.pdf: 1501907 bytes, checksum: 5610159e30f98d52848320f90146f751 (MD5) Previous issue date: 2016-02-12 / The agricultural sector has great influence in Brazilian economy. Furthermore, agricultural yield has been associated with pesticides application during crop cycle, which atrazine is applied for example, since it can cause environmental contamination when it does not reach its target. Thus, there are some essential and imperative options that can minimize contamination and negative impacts during agricultural practices. So, present study aimed at evaluating the ability of three biochars in atrazine adsorption. Therefore, three biochars produced from bamboo culm were used, whose species is Phyllostachys aurea, and temperature ranged at 350 ºC, 450 ºC and 550 ºC. The three studied biochars were named as BE350, BE450 and BE550. They were characterized based on their physical and chemical properties by elemental analysis, characterization of functional groups (Infrared Spectroscopy Fourier Transform - FTIR), surfaces morphology evaluation (Scanning Electron Microscopy - SEM) as well as specific surface area (ASEBET) and porosity. A kinetic study was carried out to determine the equilibrium period of adsorption process and the kinetic mechanism that controls such process. Langmuir and Freundlich isotherms were also modeled during this trial. Atrazine determination, after the adsorption test, was carried out by High Performance Liquid Chromatography (HPLC). The obtained analyses showed that the adsorption capacity of biochars decreased in the following order: BE 450> BE 350 > BE 550, and such capacity has been associated with the physical and chemical characteristics of biochars. The three studied biochars are well represented by the kinetic model of pseudo-second order. At last, all biochars have shown high affinity to adsorb atrazine; however, the biochar that was produced at 450 ºC has shown the highest adsorption capacity. / O setor agrícola possui grande destaque na economia brasileira, a produção agrícola está associada ao uso de pesticidas durante o ciclo das culturas, como é o caso da atrazina, que pode causar a contaminação do ambiente, quando não atinge seu alvo. Sendo assim, alternativas que minimizem as contaminações e impactos negativos da prática agrícola são essenciais e urgentes. Desta forma, o presente estudo teve por objetivo avaliar a capacidade de três biocarvões, em adsorver o herbicida atrazina. Para tanto, foram utilizados três biocarvões, produzidos a partir do colmo de bambu, da espécie Phyllostachys aurea à 350ºC, 450ºC e 550ºC, nomeados BE350, BE450 e BE550. Os biocarvões foram caracterizados quanto as propriedades físicas e químicas, por meio de análise elementar, caracterização de grupos funcionais (Espectroscopia de Infravermelho com Transformada de Fourier - FTIR), avaliação da morfologia das superfícies (Microscopia Eletrônica de Varredura - MEV), bem como, área superficial específica (ASEBET) e porosidade. Estudo cinético foi realizado, visando determinar o tempo de equilíbrio do processo de adsorção, bem como, o mecanismo cinético que controla o processo. Também foram modeladas isotermas de Langmuir e Freundlich. A determinação da atrazina, após os ensaios de adsorção, foi realizada por Cromatografia Líquida de Alta Performance (CLAE). As análises realizadas apontaram que a capacidade de adsorção dos biocarvões diminuiu na ordem de BE 450 > BE 350 > BE 550, e tal capacidade está associada às características físicas e químicas dos biocarvões. Os três biocarvões são bem representados pelo modelo cinético de pseudo-segunda ordem. Todos biocarvões exibiram elevada afinidade para a adsorção do herbicida atrazina, contudo, o biocarvão produzido à 450 ºC demonstra maior capacidade de adsorção
6

Bamboo Nutritional Composition, Biomass Production, and Palatability to Giant Pandas: Disturbance and Temporal Effects

Parsons, Jennifer L 17 August 2013 (has links)
The giant panda (Ailuropoda melanoleuca) subsists on bamboo, but lacks gastrointestinal modifications for fiber digestion. Pandas display dietary selectivity for certain plant parts; however, cues for selection are unknown, and few have examined panda feeding behavior and bamboo nutrient composition simultaneously. Bamboos are clonal plants, with seasonal cycles of nutrient accumulation related to peak photosynthesis and recruitment. These cycles can be destabilized by aboveground disturbance; however, effects of disturbance on nutritional quality and sustainability of bamboo for primary consumers have not been studied. I examined 4 factors that may contribute to bamboo nutritional quality or sustainable harvest: season, ramet maturity and age, and disturbance. I conducted a 3-year study with Phyllostachys aureosulcata (PLLAU), P. glauca (PLLGL), and P. rubromarginata (PLLRU), at the Shelby County AgriCenter, Memphis TN, applying 3 disturbance treatments in a replicated split-plot design: control, 3% and 20% annual removal of biomass. Bamboo was sampled 8 times/year and divided into shoot, leaf, and culm (central stem) for analysis of crude protein (CP), neutral- and acid-detergent fiber (NDF and ADF), ash, lipid, minerals, and acid-insoluble ash (AIA). I quantified bamboo-stand production, maturity, recruitment and mortality. Biomass removed from PLLAU was used in diet-selection trials with 2 giant pandas, observing consumption of plant parts and bamboo from different disturbance treatments, and sampling bamboo for allelochemical and starch analysis. Disturbance effects were evident only for branch and culm dry mass in PLLRU. In Year 2, drought conditions and peak roosting blackbird populations confounded results. Defoliation and guano deposition preceded changes to soil chemistry, bamboo composition, and stand structure; recruitment increased for PLLRU. After accounting for confounding factors, less-mature bamboo had greater concentrations of most nutrients, but less NDF, ADF, and K. Two-year-old ramets had greater CP, NDF, lipid, P, K, S, and Cu, but less Ca and Fe, than 1-year-old ramets. I confirmed seasonal plant-part selection by pandas, but found no correlation between leaf consumption and AIA concentration. Culm starch analyses were insufficient to establish a clear pattern. I recommend further investigation of non-structural carbohydrates in bamboo, and palatability testing of undisturbed versus disturbed bamboo, which I was unable to examine.
7

Process of carbohydrate transferring and carbon budget in Phyllostachys edulis forests / モウソウチク林における炭水化物の移動過程と炭素収支

WANG, Shitephen 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第23950号 / 農博第2499号 / 新制||農||1091(附属図書館) / 学位論文||R4||N5385(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)准教授 岡田 直紀, 教授 井鷺 裕司, 教授 柴田 昌三 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
8

[en] PHYSICAL AND MECHANICAL CHARACTERISTICS OF THE ENTIRE BAMBOO PHYLLOSTACHYS AUREA: BUCKLING BEHAVIOR / [pt] CARACTERIZAÇÃO FÍSICA E MECÂNICA DE COLMOS INTEIROS DE BAMBU DA ESPÉCIE PHYLLOSTACHYS AUREA: COMPORTAMENTO À FLAMBAGEM

MARTHA LISSETTE SANCHEZ CRUZ 01 September 2003 (has links)
[pt] Para o uso do bambu como material de engenharia é necessário realizar uma análise estatística completa das propriedades físicas, mecânicas e mesoestruturais dos colmos. Desde 1979, no Departamento de Engenharia Civil da PUC-Rio foram desenvolvidos, sob a orientação do professor Khosrow Ghavami, vários programas de investigação para o emprego do bambu e fibras vegetais na construção de edificações de baixo custo, substituindo produtos de asbesto cimento e de materiais poluentes e não renováveis . Como parte desta linha de pesquisa, pretende-se continuar os estudos para estabelecer as propriedades dos bambus apropriados para serem utilizados na construção civil. O presente trabalho concentra-se na caracterização da espécie Phyllostachys aurea, tão utilizada no mundo do artesanato e arquitetura pela sua beleza, porem tão pouco estudada no campo de engenharia, para que os resultados obtidos possam contribuir para a valorização desta espécie, incentivando seu uso na construção civil. Esta dissertação tem como objetivos principais: caracterizar as propriedades físicas, mecânicas e mesoestruturais dos colmos inteiros de bambu da espécie Phyllostachys aurea, analisando a influência das imperfeições geométricas iniciais no comportamento à flambagem . A determinação experimental das propriedades mecânicas dos colmos de bambu submetidos a ensaios de tração, cisalhamento e compressão são apresentadas, analisando-se a influência dos tratamentos preservativos na resistência mecânica dos colmos. / [en] The use of bamboo in civil construction requires a thorough analysis of its physical, mechanical and mesostructural properties. For this purpose several investigations have been carried out in the Civil Engineering Department at PUCRio since 1979. Other vegetal fibers have been studied as well for their feasibility to be used as low cost building materials in order to substitute asbestos cement products in addition to non-renewable and polluting materials such as steel and aluminum. This present study is the continuation of the investigation to establish the engineering properties of the bamboo's appropriate for civil construction. This work concentrates on the bamboo species Phyllostachys aurea which is utilized frequently in the interior design and architectural project, and in general in civil construction about which there is very little scientific information in the available national and international literature. The principal objectives of this study were to establish the physical, mechanical and mesostructural characteristics of the whole culms of the bamboo species Phyllostachys aurea and to analyze how its specific geometric imperfections influence the buckling behavior of the culm. The experimental analysis of the bamboo culm, concerning the static tensile, shear and compressive properties is presented as well as the influence of preservative treatments on their performance.
9

Detection of insect inclusions and size estimation of bamboo galls using soft X-rays

SHIBATA, Ei'ichi, 柴田, 叡弌, ITO, Masato, 伊藤, 正仁, YOSHIDA, Kazuhiro, 吉田, 和広 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
10

タケ林と二次林の主要樹種における樹幹流と林内雨の成分特性

酒井, 佳美, SAKAI, Yoshimi, 松井, 春夫, MATSUI, Haruo, 只木, 良也, TADAKI, Yoshiya 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。

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