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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.
21

Use of Pyrolyzed Soybean Hulls as Fillers in Polyolefins

Coben, Collin 09 July 2020 (has links)
No description available.
22

Fontes de fibra na alimentação de juvenis de pacu (Piaractus mesopotamicus) /

Fabregat, Thiago El Hadi Perez. January 2009 (has links)
Orientador: João Batista Kochenborger Fernandes / Banca: Elisabeth Criscuolo Urbinati / Banca: Maria Cristina Thomaz / Banca: Teresa Cristina Ribeiro Dias Koberstein / Banca: Antônio Cleber da Silva Camargo / Resumo: O objetivo deste estudo foi avaliar o efeito da utilização de dietas contendo diferentes ingredientes fibrosos (farelo de soja, casca de soja, farelo de girassol e polpa cítrica, este ultimo avaliado em dois níveis de inclusão) sobre o tempo de trânsito gastrointestinal, as digestibilidades da proteína e da energia, o desempenho, a composição corporal, os parâmetros bioquímicos, os índices organométricos e a morfometria intestinal de juvenis de pacu (Piaractus mesopotamicus). Os peixes alimentados com as dietas contendo farelo de soja e farelos de girassol tiveram os melhores resultados de digestibilidade e desempenho, sem apresentar alterações fisiológicas e metabólicas. A inclusão casca de soja na dieta atrasou o tempo de trânsito gastrointestinal, piorou a digestibilidade da proteína e da energia, prejudicou o desempenho, diminuiu as proteínas totais sangüíneas e aumentou a porcentagem de lipídeo muscular. A dieta contendo 45% polpa cítrica acelerou o tempo de trânsito gastrointestinal, piorou o desempenho, provocou alterações na composição corporal e na morfometria intestinal. Cada ingrediente fibroso, em função de sua composição de fibras alimentares e carboidratos complexos, altera o funcionamento do sistema digestório e o aproveitamento de nutrientes, com conseqüências sobre a fisiologia, o metabolismo e o desempenho dos juvenis de pacu / Abstract: This study aim was to evaluate the effects of diets containing different fiber sources (soybean meal, soybean hulls, sunflower meal and citrus pulp, this last evaluated at two inclusion levels) on gastrointestinal transit time, protein and energy digestibility of protein, performance, body composition, biochemical parameters, organometric index and intestinal morphology of juvenile pacu (Piaractus mesopotamicus). Fish fed diets containing soybean meal and sunflower meal had best digestibility and performance results, with no physiological and metabolic diseases. The inclusion of soybean hulls in the diet delayed gastrointestinal transit time, decreased the digestibility of protein and energy, worsened performance, reduced total blood proteins and increased the percentage of muscle lipid. Diet containing 45% citrus pulp accelerated gastrointestinal transit time, worsened performance, led to changes in body composition and affects the intestinal morphology. Each fibrous ingredient, depending on dietary fiber and complex carbohydrates composition, differently affects the digestive system functioning and nutrient use, with consequences on physiology, metabolism and performance of juvenile pacu / Doutor
23

Biossorção dos íons cádmio e chumbo pela casca de soja / Biossorption of Cd(II) and Pb(II) by soybean hulls

Colombo, Andréia 27 June 2013 (has links)
Made available in DSpace on 2017-07-10T18:07:58Z (GMT). No. of bitstreams: 1 Andrea Colombo.pdf: 2540597 bytes, checksum: 5361b16fecab0f39c969122aa444a7d5 (MD5) Previous issue date: 2013-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this study the soybean hulls sorption potential in Cd2+ and Pb2+ in mono and binary component systems has been investigated at batch mode. In order to evaluate the effect of untreated and treated soybean hulls biomass, metal-bearing solution pH, sorption temperature, particle grain size, and agitation velocity on the improvement of the adsorption capacity of Cd2+ and Pb2+ cations, a series of adsorption preliminary tests, in duplicates, were performed. Regarding better sorption conditions, kinetic and equilibrium sorption experiments at batch mode were carried out for both mono and binary component systems. For preliminary and kinetic sorption experiments a series of 125 mL Erlenmeyer-type flask containing 300 mg dried soybean hulls in contact with 50 mL metal-bearing solutions at a 4 mequiv. L-1 concentration of Cd2+ and Pb2+ cations under controlled temperature and agitation velocity in a shaker. Regarding the equilibrium contact time, other sorption experiments, in duplicate, consisting of a series of mixture of 50 mL metal-bearing solutions and 50-1000 mg dried soybean hulls biomass were also performed under controlled temperature and agitation velocity in a shaker. In single component systems, a cation concentration of 4 mequiv. L-1 was tested, while in binary component systems three concentration combination in Cd2+-Pb2+bearing solutions were tested. After each sorption experiment, biosorbent was separated from metal solution by a 0.45 µm pore size membrane filtration system, performing then the determination of Cd and Pb concentrations in diluted liquid samples by flame atomic absorption spectrometry. Sorption tests regarding untreated soybean hulls biomass, pH 5 for Cd2+ and pH 4 for Pb2+, 30oC sorption temperature, a mixture of different particle grain sizes, and 100 rpm agitation velocity have showed the best results on the biosorbent performance to sequestrate Cd2+ and Pb2+ cations from metal-bearing solutions. The kinetic test data have shown that the equilibrium was achieved at contact times of 120 and 180 min for Cd2+ and Pb2+, respectively. Meanwhile, 55 and 64% concentration reductions for Cd2+ and Pb2+, respectively, were also achieved. Furthermore, the pseudo-second order kinetic model has fitted better the sorption kinetic data for both tested divalent cations. The equilibrium sorption data for mono-component systems have been well fitted by the Langmuir isotherm model, with maximum sorption capacity (qmax) of 0.5091 ± 0.0054 mequiv.g-1 and 0.6577 ± 0.0218 mequiv.g-1 for Cd2+ and Pb2+, respectively. Bicomponent equilibrium data were graphically represented by a 3D adsorption surface and modeled by a modified extended-to-multicomponent Langmuir-type isotherm, obtaining good fits. The results indicates that each component maximum capacity depends on the other species at the solution, inasmuch total adsorption capacity remains constant. Besides, a second component at the solution influences the isotherm curve shape. Thus, based on sorption results, untreated soybean hulls biomass is an alternative low-cost biosorbent to be applied in treatment systems of industrial effluents containing high concentration of Cd2+ and Pb2+ cations. / O objetivo deste trabalho foi avaliar o potencial da casca de soja no processo de biossorção, em sistema fechado batelada, das espécies metálicas cádmio (II) e chumbo (II) em soluções monocomponente e bicomponente. Foram realizados testes preliminares para verificar o efeito do tratamento no biossorvente, pH da solução, temperatura de sorção, granulometria do biossorvente e velocidade de agitação, na remoção dos íons metálicos. As melhores condições obtidas nos testes preliminares foram utilizadas nos testes cinéticos e de equilíbrio, monocomponente e bicomponente. Para os testes preliminares e cinéticos foram colocados, em frasco erlenmeyer de 125 mL, 300 mg de casca de soja em contato com 50 mL de solução com concentração de aproximadamente 4 mequiv.L-1 do íon metálico (cádmio ou chumbo). Para os testes de equilíbrio foram colocados, em frasco erlenmeyer de 125 mL, 50 a 1000 mg de biomassa com 50 mL de solução. No teste de equilíbrio monocomponente, a concentração inicial da solução foi em torno de 4 mequiv.L-1 do íon metálico (cádmio ou chumbo), e no bicomponente, as seguintes combinações de concentrações de cádmio e chumbo foram utilizadas: 4 - 4 mequiv L-1, 1 - 3 mequiv L-1; e 3 - 1 mequiv L-1. Todas as amostras foram mantidas com temperatura e agitação controladas por período pré-determinado. Em seguida, foram filtradas em membrana com tamanho dos poros de 0,45 µm, diluídas e analisadas em relação a concentração dos íons inicialmente presentes na solução por espectrofotometria de absorção atômica. Todos os testes foram realizados em duplicata. Os resultados dos testes preliminares mostraram que as melhores condições para biossorção dos íons cádmio e chumbo foram casca de soja sem tratamento (in natura), pH 4, temperatura de adsorção de 30°C, mistura granulométrica do biossorvente e velocidade de agitação 100 rpm. Nos testes cinéticos o tempo de equilíbrio foi de 120 min para o cádmio, com taxa de remoção de 55%, e de 180 min para o chumbo, com uma taxa de remoção de 64%. O modelo cinético de pseudosegunda ordem foi o que melhor representou os dados experimentais para ambos os íons metálicos. Aos dados de equilíbrio, o modelo que melhor se ajustou foi o de Langmuir cujos parâmetros q_max e b para os íons de Cd (pH 5) e Pb (pH 4) foram: 0,50910 ± 0,0054 mequiv.g-1 e 1,16236 ± 0,03242 L.mequiv-1 e 0,65773 ± 0,02181 mequiv.g-1 e 0,74735 ± 0,09479 L.mequiv-1. Os dados de equilíbrio, bicomponente, foram representados graficamente por meio da superfície de adsorção e modelados pelo modelo de Langmuir estendido modificado, obtendo-se bom ajuste. Os resultados mostraram que a máxima capacidade de cada espécie metálica é um parâmetro dependente de outra espécie da mistura, enquanto que a capacidade de adsorção total assume um valor constante. Além disso, a presença de outro metal em solução afetou a forma da curva da isoterma. Assim, pelos resultados obtidos pode-se afirmar que a casca de soja possui grande potencial para o tratamento de efluentes contendo cádmio e chumbo.
24

<b>PRE- AND POST-SYNCHRONIZATION STRATEGIES TO IMPROVE CONCEPTION RATE AND REPRODUCTIVE EFFICIENCY IN REPLACEMENT BEEF HEIFERS</b>

Griffin T Nicholls (8581524), Ronald P. Lemenager (5236994), Kara Stewart (5236979), Bethany Funnell (5236985), Elizabeth Karcher (19206850) 27 July 2024 (has links)
<p dir="ltr">Nulliparous replacement beef heifers represent an opportunity to improve both genetic potential and lifetime production within the herd. However, advances in reproductive efficiency and synchrony in the herd require heifers to conceive earlier than multiparous cows in order to account for the extended postpartum interval following first-time parturition. Further, those heifers that achieve early calving dates continue to calve early throughout their lifetime. This early calving results in increased weaning weights and better synchrony in subsequent years. One obstacle producers face when breeding nulliparous heifers is the ability to identify which animals have reached puberty at the initiation of the breeding season. This results in the variation observed in synchronization success within a group of heifers. In Chapter 2 our laboratory formulated a study to analyze the efficacy of the 7-d CO-synch + CIDR protocol when utilizing short-term exposure to a progestin (melengestrol acetate, MGA) as a pre-synchronization protocol. Our hypothesis was that the heifers may respond more efficiently to an orally fed progestin as the increase in serum progesterone is less pronounced, when compared to the CIDR. This first study resulted in a protocol application error, in which MGA was fed an extra day (8 vs. 7). This additional day of treatment with MGA following the administration of a prostaglandin eliminated our laboratory’s opportunity to collect meaningful data from this first attempt. Thus, it was pertinent to restart the experiment in an attempt to obtain data for analysis. In order to avoid confounding data, half of the heifers in each treatment received a new treatment, while the other half remained on the treatment assigned during the first attempt. After completing the second round of experiments it was observed that at the first pregnancy check (study day 30), the heifers that were originally assigned to MGA, but were switched to a CIDR for the second attempt numerically outperformed their counterparts in the other three formulated treatment groups. In an attempt to replicate these results, a second study was formulated (Chapter 3), to mimic the timeline from the preliminary study. This resulted in a pre-synchronization treatment protocol prior to the initiation of the breeding season synchronization protocol. Previous studies that have been conducted with similar protocols were designed to provide heifers with a pre-synchronization period that would aid in the attainment of puberty prior to their first attempt at breeding through exposure to progesterone. The purpose of the Chapter 3 experiment was to evaluate the effects of feeding melengestrol acetate (MGA®) as a pre-synchronization for 10 days immediately prior to estrous synchronization and fixed-timed artificial insemination (FTAI). The ten days were chosen as this was a novel protocol that was the result of the preliminary study and the subsequent restart. Ninety-three crossbred heifers (395.67 ± 5.37 kg) were blocked by BW, genetics, and reproductive tract scores and allotted to 3 treatments. The 3 treatment groups were: 7-day CO-synch + CIDR without pre-synchronization (CON, n=31); 25 mg PGF2α (Lutalyse®) followed immediately by MGA feeding for 7 d prior to the start of the 7-day CO-synch + CIDR program (PRE, n=31); and 25 mg PGF2α followed immediately by MGA feeding for 7d followed 10 d later by the start of the 7-day CO-synch + CIDR program (PRE+10, n=31). The 7-day Co-synch + CIDR protocol in all three treatments was initiated on d 0 by administering a 2 cc IM injection of GnRH (Cystorelin®) and placing a CIDR into the vagina. The CIDRs were removed 7 days later and accompanied by 25 mg IM injection of PGF2α. An injection of GnRH occurred 60-66 hours following PGF2α at FTAI with frozen semen from a single bull. Ten days after FTAI, heifers were exposed to a bull. Estrotect® patches were applied throughout the study to assess estrous behavior. Ovaries were visualized by transrectal ultrasonography 24 hours post-FTAI to determine whether ovulation occurred. Pregnancy was determined on days 40, 64, and 109 post-FTAI via transrectal ultrasonography. Blood was collected via jugular venipuncture (d -19 and -12, MGA initiation and termination, days 0, 7, and 9) and serum progesterone determined. Performance data were analyzed using the MIXED procedure and conception data were analyzed using the GLIMMIX procedure of SAS. Heifers in the PRE+10 treatment group had higher levels of progesterone (P=0.04) at d 0 compared to PRE heifers. At d 7 (CIDR removal) there was a tendency (P=0.07) for PRE+10 heifers to have higher levels of progesterone than PRE, but did not differ by d 9 (FTAI, P=0.36). FTAI conception rates in heifers in the PRE treatment group (63%) tended (P = 0.09) to be higher compared to the controls (35%), but not different from PRE+10 (43%), with no differences in season-long pregnancy rates (P > 0.15). Pre-synchronization with MGA immediately prior to FTAI synchronization appears to increase conception rates early in the breeding season in beef heifers. In Chapter 4, our laboratory analyzed the efficacy of supplementation strategies post-insemination. Unlike the first two experiments, the third study focused on reproductive failure that occurs after insemination. The overarching goal remained the same, increasing the reproductive efficiency within our nulliparous heifer herd. A common practice for beef producers in the United States is to use estrous synchronization, and immediately turn heifers out to lush spring pasture immediately following FTAI. The fresh forage is high in water content which lowers dry matter intake (DMI) and creates a negative energy balance. Ultimately, this reduced energy intake can result in a reduction in reproductive performance. In the Chapter 4 our laboratory formulated a supplementation strategy utilizing the SmartFeed™ technology to deliver soybean hulls to our treatment group following insemination for 45 days. The utilization of the SmartFeed® technology provided the opportunity to analyze the efficacy of the supplementation strategy using each individual animal as an experimental unit. Sixty-two nulliparous crossbred heifers were fed in drylot to obtain moderate body condition prior to breeding at d 0 via FTAI and trained to utilize the SmartFeed™ system.Heifers were blocked by weight and body condition score to either the soybean hull supplementation group (SOY) or the non-supplemented control group (CON). . Heifers in the treatment group received their supplementation by entering the SmartFeed™ system, allowing for RFID controlled release of 2.27 kg. per head each day for 45 days. Scales located beneath each feed pan sent real time weight data for regulation and analysis on individual animal feeding behavior. On study d 6, a subset of the nulliparous crossbred heifers (n = 12; n = 6/ treatment) were transported by trailer from the Feldun Purdue Agricultural Center to Purdue West Lafayette main campus (approximately 217.74 km.). The subset of heifers had embryos flushed and evaluated for embryo quality and number of live/dead cells. Ultrasonography was utilized to monitor ovarian activity throughout the duration of the study and to determine pregnancy status 30 days after FTAI and 30 days after the 45-day breeding season. Though conception rates were not statistically (P=0.17) different (SOY 16/25; 64% vs. CON 11/25; 44%) when comparing treatment groups, the numerical differences suggest there is potential in pursuing a similar supplementation strategy following breeding in nulliparous beef heifers. The supplementation of SBH resulted in greater weight gain over time (P = 0.04), potentially explaining the numeric improvement in conception rate. The two pre-synchronization studies from Chapters 2 and 3 resulted in numerical improvements in conception rate as a result of exposing replacement heifers to a source of progestin prior to the initiation of their synchronization protocol. The implementation of progesterone priming mitigates the occurrence of short cycles and immature oocyte maturation at the time of ovulation. Based on results from previous studies conducted by our laboratory, the source of progestin greatly determines the timing and concentration of P4 circulating in replacement heifers immediately following treatment. Additionally, the 7 & 7 estrous synchronization protocol has grown in popularity and implementation. This protocol when broken down is very similar to the pre-synchronization protocol our laboratory utilized for the first two studies. Several studies have been conducted to analyze the efficacy of the 7 & 7 and the conception data was comparable to the MGA derived protocol. Thus, one potential direction for the future would be to formulate a research study that compares the two protocols. Since the conception rates were similar, it may be hypothesized that the MGA protocol could be more widely accepted as there is a reduction number of times animals are handled.</p>
25

Emprego da casca de soja como adsorvente na remoção de corantes reativos têxteis / Use of soybean hulls as an adsorbent in reactive textile dyes removal

Honorio, Jacqueline Ferandin 19 February 2013 (has links)
Made available in DSpace on 2017-07-10T18:07:57Z (GMT). No. of bitstreams: 1 Jacqueline Ferandin Honorio.pdf: 4266327 bytes, checksum: 1a3607097a182468e16f0370c8918398 (MD5) Previous issue date: 2013-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The textile industry is known for high use of chemicals such as dyes, and generating large volumes of wastewater that contaminates water, a fact that has encouraged the research and improvement of treatment techniques. This study aimed to employ in natura soybean hulls in the removal of reactive dyes Crimson Sidercron HEXL (RCS-HEXL) and Blue BF-5G (RABF-5G). The point of zero charge (PZC) of soybean hulls was 6.76. The kinetics of the dye RCS-HEXL performed under the experimental conditions C0= 350 mg L-1, Dp= 0.215 mm, dosage= 8 g L-1, pH 2, temperature 30 °C was reached experimental qeq 38.039 mg g-1 in a time of 10 hours. In the kinetics of dye RABF-5G one experimental qeq of 57.473 mg g-1 was obtained under the conditions C0= 400 mg L-1, Dp= 0.725 mm, dosage= 6 g L-1, pH 2, temperature 30 °C 24 hours. The model of the pseudo-second order kinetics represented best of both dyes, showing R2= 0.989. The Langmuir isotherm model for 30 oC showed the maximum adsorption capacity of 44.356 mg g-1 and 72.427 mg g-1 for dyes RCS-HEXL and RABF-5G, respectively. Soybean hulls being a low-cost agro-industrial by-product proves to be a potential adsorbent for the removal of textile dyes investigated. / O setor têxtil é conhecido pela elevada utilização de produtos químicos, como os corantes, e gerador de grandes volumes de efluente que contaminam águas, fato que tem incentivado a pesquisa e o aprimoramento de técnicas de tratamento. Este trabalho teve como objetivo empregar a casca de soja in natura na remoção dos corantes reativos Crimson Sidercron HEXL (RCS-HEXL) e Azul BF-5G (RABF-5G). O ponto de carga zero (PCZ) da casca de soja foi de 6,76. A cinética do corante RCS-HEXL realizada nas condições experimentais de C0= 350 mg L-1, Dp=0,215 mm, dosagem=8 g L-1, pH 2, temperatura 30°C foi obtido um qeq experimental de 38,039 mg g-1 em um tempo de 10 horas. Na cinética do corante RABF-5G um qeq experimental de 57,473 mg g-1 foi obtido nas condições de C0= 400 mg L-1, Dp=0,725 mm, dosagem=6 g L-1, pH 2, temperatura 30°C em 24 horas. O modelo de pseudo-segunda ordem representou melhor a cinética de ambos os corantes, apresentando R2 de 0,989. O modelo de isoterma de Langmuir para a temperatura de 30oC apresentou capacidade máxima de adsorção de 44,356 mg g-1 e 72,427 mg g-1, para os corantes RCS-HEXL e RABF-5G, respectivamente. A casca de soja por ser um subproduto agroindustrial de baixo custo demonstra ser um adsorvente potencial para a remoção dos corantes têxteis investigados.

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