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Local Water Slamming of Nonlinear Elastic Sandwich Hulls, and Adiabatic Shear Banding in Simple Shearing Deformations of Thermoelastoviscoplastic BodiesXiao, Jian 03 May 2013 (has links)
We have developed a third-order shear and normal deformable plate/shell theory (TSNDT) incorporating all geometric nonlinearities and used it to analyze, by the finite element method (FEM), transient finite deformations of a sandwich beam with two face sheets and the core made of St. Venant-Kirchhoff materials. A triangular cohesive zone model with stress based criterion for delamination initiation and energy based relation for complete separation is used to analyze delamination failure in a beam under mixed-mode loading. We have studied transient post-buckling deformations and delamination progression in an axially compressed and initially delaminated clamped-clamped sandwich beam. The buckling load for transient deformations exceeds that for static deformations and the increase depends upon the loading rate. This FE software for analyzing deformations of sandwich beam is coupled with that based on the boundary element method (BEM) for studying time-dependent deformations of water and the coupled software is used to analyze deformations of flexible curved hulls due to water slamming loads. The water is assumed to be inviscid and incompressible and undergo irrotational deformations. The Laplace equation for the velocity potential is numerically solved by the BEM with normal velocity and pressure assumed to be continuous across the interface between the hull and the water. Challenging issues resolved in this work include finding the wetted surface of the hull, nonlinear deformations of the fluid due to convective part of acceleration, effects of geometric nonlinearities on hull\'s deformations, resolution of the jet tip, as well as the initiation and propagation of delamination between the face sheets and the core. It is found that both delamination and geometric nonlinearities significantly affect the hydrodynamic pressure acting on the hull, and transverse shear deformations contribute more to the strain energy absorbed by the core than its transverse normal deformations. <br />We have used the discontinuous basis functions to derive the Galerkin formulation of a nonlinear problem involving simple shearing deformations of a homogeneous and isotropic thermo-elasto-visco-plastic body with uniform deformations perturbed to simulate the effect of a defect. The resulting coupled nonlinear ordinary differential equations are integrated with respect to time by using the package, LSODE (Livermore Solver for Ordinary Differential Equations). Computed results showing localization of deformations into narrow regions are found to agree well with those found by the FEM, and spatial variations of the shear stress are smoother than those obtained by the FEM.<br /><br /> / Ph. D.
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Effects of Corn Silage Hybrids and Dietary Nonforage Fiber Sources on Productive Performance in Early Lactating Dairy Cows Fed High Forage DietsHolt, Michael Shane 01 May 2010 (has links)
This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportion of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36 ± 6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d periods. Treatments were: 1) conventional corn silage (CCS)-based diet without NFFS, 2) CCS-based diet with NFFS, 3) brown midrib corn silage (BMRCS)-based diet without NFFS, and 4) BMRCS-based diet with NFFS. Diets were isonitrogenous and isocaloric. Sources of NFFS consisted of ground soyhulls and pelleted beet pulp to replace a portion of AH and CS in the diets. In vitro 30-h NDF degradability was greater for BRMCS than CCS (42.3 vs. 31.2%). Neither CS hybrids nor NFFS affected intake of DM and nutrients. Digestibility of N, NDF, and ADF tended to be greater for cows consuming CCS-based diets. Milk yield was not influenced by CS hybrids and NFFS. However, a tendency for an interaction between CS hybrids and NFFS occurred with increasing milk yield due to feeding NFFS with the BMRCS-based diets. Yields of milk fat and 3.5% FCM decreased when feeding the BMRCS-based diet, and there was a tendency for an interaction between CS hybrids and NFFS by further decreased milk fat concentration because of feeding NFFS with BMRCS-based diet. Although feed efficiency (milk/DM intake) was not affected by corn silage hybrids and NFFS, there was an interaction between CS hybrids and NFFS because feed efficiency increased when NFFS was fed only with BMRCS-based diet. Total VFA production and individual molar proportion were not affected by diets. Dietary treatments did not influence ruminal pH profiles except that duration (h/d) of pH < 5.8 decreased when NFFS was fed in CCS-based diet but not in a BMRCS-based diet, causing a tendency for an interaction between CS hybrids and NFFS. Overall measurements in our study reveal that high forage NDF concentration (20% DM on average) may eliminate potentially positive effects of BMRCS. In the high forage diets, NFFS exerted limited effects on productive performance when they replaced AH and CS. Although the high quality AH provided adequate NDF (38.3% DM) for optimal rumen fermentative function, the low NDF concentration of the AH and the overall forage particle size reduced physically effective fiber and milk fat concentration.
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USE OF PYROLYZED SOYBEAN HULLS AS ECO-FRIENDLY REINFORCEMENTFILLER IN STYRENE BUTADIENE RUBBERZOU, YU 29 August 2019 (has links)
No description available.
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A numerical investigation into the heave, sway and roll motions of typical ship like hull sections using RANS numerical methodsHenning, H. L. 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The hydrodynamic characteristics of three typical ship-like hull sections, in
different motions, are numerically investigated using FLUENT, 2009. These
simple shapes, namely a v-bottom (triangle) hull, a at-bottom (square) hull
and a round-bottom (semi-circle) hull, are investigated in uncoupled heave,
sway and roll. The problem is described in two dimensions. A combination of
numerical methods and models, found in literature, are used to conduct this
investigation. Hull characterisation is achieved through the use of hull mass
and damping coe cients. These numerically determined coe cients are compared
to experimental work conducted by Vugts (1968). A good correlation
between the numerical and experimental results exists for the heave and sway
cases. By normalising the coe cients, different hulls are comparable to one
another. The numerical models used are validated and veri ed. Roll motion
remains largely unsolved for very large angles of roll (in excess of 11°). Different
uid ow phenomena occurring around the hull sections have varying
degrees of in uence on the motions of a hull. It is found that not one of the
turbulence models investigated can be employed to globally solve each type
of hull-motion case. Also, forced oscillations in computational simulations require
considerably more computational time than free-decay oscillating hull
simulations. / AFRIKAANSE OPSOMMING: Die hidrodinamiese karakteristieke van verskillende skeepsrompvorms, in verskeie
bewegingswieë, is numeries ondersoek met behulp van FLUENT, 2009.
Drie eenvoudige vorms ('n v-bodem (driehoek), plat-bodem (reghoek) en rondebodem
(semi-sirkel) romp) is onderskeidelik ondersoek in opwieg, dwarswieg en
rol. Die probleem is twee-dimensioneel. Daar is gebruik gemaak van 'n kombinasie
van numeriese metodes en modelle, uit die literatuur, om die ondersoek
uit te voer. Die rompe is gekarakteriseer met behulp van massa- en dempingskoëffi siënte. Hierdie numeries bepaalde koë ffisiënte is vergelyk met die
eksperimentele werk van Vugts (1968). Daar bestaan 'n goeie korrelasie tussen
die numeriese en eksperimentele resultate vir die opwieg en dwarswieg gevalle.
Die koë ffisiënte is genormaliseer om die verskeie rompvorms te vergelyk. Die
numeriese modelle is geverifi eer en valideer. Rolbewegings is onopgelos vir
groot rolhoeke (groter as 11°). Die mate waartoe die romp se beweging beïnvloed
word deur die verskillende vloei verskynsels wat om die rompe ontstaan,
verskil. Daar is bevind dat geen van die turbulensie modelle gebruik kan word
om alle skeepsbeweging-gevalle op te los nie. Gedwonge-ossilasie numeriese
simulasies benodig meer berekeningstyd as vrye-verval ossilasie gevalle.
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Design and optimization of hydrofoil-assisted catamaransMigeotte, Gunther 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: This work is concerned with the hydrodynamic design of hydrofoil-assisted catamarans.
Focus is placed on the development of new and suitable design methods and
application of these to identify the most important geometric parameters of catamaran
hulls and hydrofoil configurations that influence efficiency and performance. These
goals are pursued by firstly gaining a thorough understanding of the governing hydrodynamic
principles involved in the design process. This knowledge is then applied to
develop new and improved experimental techniques and theoretical methods needed
for design. Both are improved to the extent where they can be applied as design
tools covering the important semi-displacement and semi-planing speeds, which are
the focus of this study.
The operational speed range of hydrofoil-assisted catamarans is shown to consist of
three distinct hydrodynamic phases (displacement, transition and planing) and that
different hydrodynamic principles govern vessel performance in each phase. The hydrodynamics
are found to differ substantially from that of conventional high-speed
craft, primarily due to the interaction between the hull and the hydrofoils, which
is found to vary with speed and results in the need for more complex experimental
procedures to be followed if accurate predictions of resistance are to be made.
Experimental predictions based on scaled model tests of relatively small hydrofoilassisted
catamaran models are found to be less accurate than that achievable for
conventional ships because of the inability to correct for all scaling errors encountered
during model testing. With larger models scaling errors are encountered to a lesser
degree. The most important scale effect is found to be due to the lower Reynolds
number of the flow over the scaled foils. The lower Reynolds number results in higher
drag and lower lift coefficients for hydrofoils compared with those achieved at full
scale. This effect can only be partially corrected for in the scaling procedure using
the available theoretical scaling methods.
Presently available theoretical methods commonly used for the design of conventional
ships were found to be ill adapted for modeling the complex hydrodynamics
of hydrofoil-assisted catamarans and required further development. Vortex lattice
theory was chosen to model the flow around hydrofoil-assisted catamarans as vortex
theory models the flow around lifting surfaces in the most natural way. The commercial
code AUTOWING is further developed and generalized to be able to model the
complex hull-hydrofoil interactions that change with speed. The method is shown to
make good predictions of all hydrodynamic quantities with accuracies at least as good
as that achievable through model testing and therefore fulfills the requirements for a
suitable theoretical design tool.
The developed theoretical and experimental design tools are used to investigate the
design of hydrofoils for hydrofoil-assisted catamarans. It is found that the main parameter
needing consideration in the hydrofoil design is selection of a suitable hydrofoil
lift fraction. A foil lift fraction in the order of 20-30% of the displacement weight
is needed if resistance improvements using hydrofoil assistance are to be obtained
over the hull without foils. It is often more favorable to use higher foil lift fractions
(50%+) as the resistance improvements are better, although careful attention should
then be given to directional and pitch-heave instabilities. The Hysuwac hydrofoil
system patented by the University of Stellenbosch is found to be hydrodynamically
optimal for most hullforms.
The hullform and in particular the curvature of the aft buttock lines of the hull are
found to have an important influence on the achievable resistance improvements and
behaviour of the hydrofoil-assisted hull at speed. Hull curvature is detrimental to
hydrodynamic performance as the suction pressures resulting from the flow over the
curved hull counter the hydrofoil lift. The hullform best suited to hydrofoil assistance
is found to be one with relatively straight lines and hard chine deep- V sections.
The main conclusion drawn from this study is that hydrofoil-assistance is indeed
suitable for improving the performance and efficiency of catamarans. The design and
optimization of such vessels nevertheless requires careful consideration of the various
resistance components and hull-foil interactions and in particular, how these change
with speed. The evaluation of resistance for design purposes requires some discipline
between theoretical analysis and experimental measurements as the complexity of
the hydrodynamics reduce the accuracies of both. Consideration of these factors
allows hulls and hydrofoils to be designed that are efficient and also free of dynamic
instabilities. / AFRIKAANSE OPSOMMING: Hierdie studie is gerig op die hidrodinamiese ontwerp van hidrovleuel-gesteunde katamarans.
Daar word gefokus op die ontwikkeling van nuwe en geskikte ontwerpmetodes,
asook die toepassing van hierdie metodes om die belangrikste geometriese parameters
van katamaranrompe en hidrovleuel-konfigurasies wat 'n invloed op doeltreffendheid
en werkverrigting het, te identifiseer. As aanloop tot die studie is 'n deeglike begrip
van die onderliggende hidrodinamiese beginsels bekom. Hierdie kennis is toegepas om
nuwe en verbeterde eksperimentele en teoretiese tegnieke te ontwikkel wat nodig is vir
die ontwerp van hidrovleuel-gesteunde katamarans in die belangrike deels-verplasing
en deels-planering spoedbereike.
Daar word getoon dat die bedryfspoedbereik van 'n hidrovleuel-gesteunde katamaran
uit drie onderskeibare hidrodinamiese fases bestaan, naamlik verplasing, oorgang en
planering, en dat verskillende hidrodinamiese beginsels die vaartuig se werkverrigting
in elke fase bepaal. Daar is ook gevind dat die hidrodinamika wesentlik verskil van dié
van konvensionele hoëspoed-vaartuie, hoofsaaklik as gevolg van die interaksie tussen
die romp en die hidrovleuels wat wissel na gelang van die spoed. Hierdie interaksies
moet in ag geneem word gedurende die ontwerpproses en beide eksperimentele en
teoretiese metodes is nuttig om die omvang daarvan te bepaal.
Daar is gevind dat die eksperimentele voorspellings gebaseer op toetse met relatief
klein skaalmodelle van hidrovleuelgesteunde katamarans minder akkuraat is as dié wat
bereik kan word met konvensionele skepe. Dit is omdat al die skaalfoute wat tydens
die toetsing met die model ontstaan, nie gekorrigeer kan word nie. Die belangrikste
skaaleffek is as gevolg van die laer Reynoldsgetal van die vloei oor die afgeskaalde
vleuels. Groter modele Die laer Reynoldsgetal lei tot hoër sleur- en hefkoëffisiënte in
vergelyking met dié vir die volskaal-hidrovleuels. Wanneer die beskikbare teoretiese
metodes gebruik word, kan daar slegs gedeeltelik vir hierdie effek in die skaalprosedure
gekorrigeer word. Daar is ook vasgestel dat die skaaleffekte op die Reynoldsgetal
verminder word wanneer die hidrovleuels baie nabyaan die vrye oppervlakte is. Dit
lei daartoe dat eksperimentele voorspellings van werkverrigting meer akkuraat is vir
die ontwerpe waar die hidrovleuels nie so diep onder die water is nie.
Daar is gevind dat die teoretiese metodes wat tans beskikbaar is en algemeen vir
die ontwerp van konvensionele skepe gebruik word nie die komplekse hidrodinamika
van hidrovleuel-gesteunde katamarans kan modelleer nie. Die werwelroosterteorie is
gekies om die vloei om hidrovleuel-gesteunde katamarans te modelleer aangesien dié
teorie die vloei om hefvlakke op die natuurlikste manier weergee. Die kommersiële
kode AUTOWING is verder ontwikkel en veralgemeen om ook die komplekse spoed-afhanklike interaksies van die romp en hidrovleuel te kan modelleer. Hierdie metode
lewer goeie voorspellings van al die hidrodinamiese maatstawwe met akkuraathede
wat ten minste so goed is soos di wat met modeltoetsing bereik word en voldoen
daarom aan die vereistes vir 'n geskikte teoretiese ontwerpmetode.
Die teoretiese en eksperimentele ontwerpmetode wat ontwikkel is, word gebruik om
die ontwerp van hidrovleuels vir hidrovleuel-gesteunde katamarans te ondersoek. Daar
is gevind dat die belangrikste parameter wat in die hidrovleuel-ontwerp in ag geneem
moet word, die keuse van 'n geskikte hidrovleuelhefverhouding is. Om in rompe met
hidrovleuelsteun verbeterings in die weerstand te kry in vergelyking met rompe sonder
vleuels, is 'n vleuel-hef-verhouding van 20-30 persent van die verplasingsgewig
nodig. Dit is dikwels beter om hoër vleuel-hef-verhoudings (van 50 persent of meer)
te gebruik omdat die verbetering in weerstand dan groter is. Daar moet dan egter
gewaak word teen rigtings- en hei-hef-onstabiliteite. Daar is gevind dat die Hysuwachidrovleuel-
stelsel wat deur die Universiteit van Stellenbosch gepatenteer is, hidrodinamies
optimaal is vir die meeste rompvorms.
Daar is gevind dat die vorm van die romp en veral die kromming van die lyne gevorm
deur vertikale snitte deur die romp (Engels: "aft buttock lines") van die romp 'n
belangrike invloed het op die bereikbare weerstandsverbeterings en die gedrag van die
hidrovleuel-gesteunde romp wat op spoed is. Die kromming van die romp is nadelig
vir die hidrodinamiese werksverrigting aangesien die suigdruk as gevolg van die vloei
oor die gekromde romp die hefkrag van die hidrovleuels teenwerk. Die rompvorm wat
die geskikste is vir hidrovleuel-ondersteuning is 'n romp met relatiewe reguit lyne en
skerp hoekige diep- V seksies.
Die belangrikste gevolgtrekking waartoe tydens die studie gekom is, is dat hidrovleuelondersteuning
wel geskik is vir die verbetering van die werkverrigting en die doeltreffendheid
van katamarans. Die ontwerp en optimering van sodanige vaartuie verg
nogtans die noukeurige oorweging van die verskeie weerstandskomponente en rompvleuel-
interaksies en veral hoe hierdie interaksies verander met spoed. Die evaluering
van die weerstand vir die doeleindes van ontwerp verg dissipline tussen die teoretiese
analise en die eksperimentele metings aangesien die kompleksiteit van die hidrodinamika
die akkuraatheid van die algemeen-gebruikte teoretiese en eksperimentele
metodes vir die hidrodinamiese ontwerp verminder. As hierdie faktore in ag geneem
word, kan rompe en hidrovleuels ontwerp word wat doeltreffend is en ook vry is van
dinamiese onstabiliteite.
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Analysis of ship hull and plate vibrations caused by wave forcesUnknown Date (has links)
In the present dissertation, the hydrodynamic and hydro-elastic characteristics of ship hull and plate vibrations are analyzed using theoretical and numerical methods. The wave forces are determined using a suite of methods which include the Froude-Krylov method for incident wave forces, Wagner's method and ABS rules for the slamming wave force, and numerical methods for nonlinear wave radiation forces. Finite difference methods are developed to determine the wave forced vibrations of ship hull plates which are modeled using a range of plate theories including nonlinear plate theory with and without material damping and orthotropic plate theory for stiffened hull plates. For small amplitude deformation of thin plates, a semi-theoretical superposition method is used to determine the free and forced vibrations. The transient ship hull vibration due to whipping is also analyzed using the finite difference method. Results, in the form of deformations and stress distributions, are obtained for a range of scantling and wave parameters to identify key parameters to consider in ship structural design. / by Fnu Lakitosh. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
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OBTENÇÃO E CARACTERIZAÇÃO DE CELULOSE MICROFIBRILADA DE CASCA DE SOJA E SEUS NANOCOMPÓSITOS COM POLIPROPILENOPeres, Nayana Reggiani 18 December 2013 (has links)
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Previous issue date: 2013-12-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The development of new materials takes into account factors such as need and sustentabilidade.Novas trends in modifying properties of polymeric materials have
been observed due to increasing concern about the environment and the constant search by the use of fillers in polymeric materials. Among them, there are the
lignocellulosic fibers, which in addition to reinforcing the polymer, are biodegradable low cost, low density and have no abrasive characteristic. The agro-industrial
residues are a great source of raw materials, especially in the case of soybean hulls, which is a waste in abundance in our region ( Paraná ). However, it is not always
possible to obtain the best features with the Shell Soy Gross ( CSB ) . Thus , in a first step we sought to obtain microfibrillated pulp from the CSB . Conducted to obtain
microfibrillated pulp by grinding the colloid mill, proven by analysis of Zeta Potential . And then be obtained twin screw extruder via nanocomposites with the incorporation
of 1, 3 and 5% of microfibrillated cellulose. Finally, the nanocomposites were characterized by analysis of tensile test scanning electron microscopy, atomic force microscopy, X-ray diffraction, rheological analysis, thermogravimetry, and mechanical impact tests. Through the zeta potential was proved that the dimensions were
namometricas the SEM and AFM demonstrated good adhesion of the microfibrillated cellulose, XRD confirmed the crystallinity. According to rheological analysis showed
an increase in molecular weight , with the incorporation of cellulose microfibrillated there was a slight increase in impact strength, and an increase in the stiffness of
nanocomposites. / O desenvolvimento de novos materiais leva em conta fatores como necessidade e sustentabilidade. Novas tendências na modificação de propriedades dos materiais
poliméricos têm sido observadas devido à crescente preocupação com o meio ambiente e a constante busca pela utilização de cargas em materiais poliméricos.
Entre elas, destacam-se as fibras lignocelulósicas, que além de reforçar o polímero, são biodegradáveis, de baixo custo, baixa massa específica e não possuem
característica abrasiva. Os resíduos agroindustriais são uma ótima fonte de matériaprima, principalmente no caso da casca de soja, que é um resíduo em abundância
em nossa região (Paraná). No entanto, nem sempre é possível obter as melhores características com a Casca de Soja Bruta (CSB). Deste modo, em uma primeira etapa buscou-se a obtenção de celulose microfibrilada, a partir da CSB. Realizou-se a obtenção da celulose microfibrilada através da moagem no moinho coloidal, comprovada pela análise de Potencial Zeta. E em seguida, obtiveram-se via extrusora dupla rosca os nanocompósitos com a incorporação de 1, 3 e 5% de celulose microfibrilada. Finalmente, os nanocompósitos foram caracterizados através das análises de microscopia eletrônica de varredura, microscopia de força atômica, difração de raios X, analise reológica, termogravimetria, ensaios mecânicos de impacto e ensaios mecânicos de tração. Através do potencial zeta provou-se que as dimensões são namometricas, o MEV e MFA comprovou a boa adesão da celulose microfibrilada, o DRX comprovou a cristalinidade. Segundo, a analise reológica houve aumento da massa molar. Com a incorporação da celulose microfibrilada houve um ligeiro aumento na resistência ao impacto, e um aumento na rigidez dos nanocompositos,
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Dietas de alto grão no comportamento, desempenho e qualidade da carne de novilhos confinados / High grain diet in the behavior, performance and meat quality of feedlot steersCallegaro, álisson Marian 14 October 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to assess the feasibility of the use of soybean hulls and/or white oat grain in the diet of feedlot steers fed exclusively with concentrate and its response on performance, ingestive behavior, non-carcass components and meat and carcass characteristics. We used thirty three crossbred steers with Charolais or Nellore predominance, with average age and weight of 20 months and 269.72 kg. The animals were randomly distributed in the treatments, blocked according to their genetic predominance, and kept in individual pens. Diets were isonitrogenous, being the treatments: Soybean hulls; White oat grain and the Mixture (equal parts of soybean hulls and oat grain), plus limestone and protein nucleus. There was no difference (P> 0.05) among treatments for dry matter intake (7.42 kg day-1; 2.23% BW). Despite the similar dry matter intake, steers of the mixture treatment had greater weight gain compared to the soybean hulls treatment (1.300 vs. 0.972 kg day-1), but these two treatments were similar to the oat grain (1.203 kg-1 day). Animals fed soybean hulls remained longer time in total idle (1,164 minutes) compared with those fed the mixture (1.061 min), which in turn, remained longer in idling than animals fed oat grain (971 min) (P <0.05); for the total rumination time we observed a contrary behavior, 69 min, 217 min and 343 min, respectively (P <0.05). Carcass weights and yields of hot (65.99%) and cold carcass (64.45%) of the steers, expressed in empty body weight were not affected by treatments (P> 0.05). There was higher internal fat in the abdominal cavity in steers from the oat grain treatment in relation to others (16.22 vs 20.58 kg; 4.93 vs 6.15 kg 100 kg-1 empty body) (P <0.05). The absolute and relative weights of all the internal organs and external components of the steers was similar (P> 0.05). Steers fed oat grain and the mixture had greater blood volume in relation to steers fed soybean hulls (3.53 vs 2.80 kg 100 kg-1 of empty body). Carcass quantitative traits and physical composition, with exception of forequarter, muscle and fat percentage, were not affected (P>.05) by the treatments. The use of diets with 100% concentrate are technically viable for steers fed diets based on oat grain or the mixture. The high contend of soluble neutral detergent fiber in treatment based on soybean hulls, is not sufficient to promote adequate ingestive behavior (rumination time) of steers compared to the other treatments. Diets based exclusively on concentrate do not influence the empty body weight of steers feedlot finished and promote similar (P>.05) meat qualitative characteristics. / Objetivou-se investigar a viabilidade da casca de soja e/ou grão de aveia branca, na dieta de novilhos terminados exclusivamente com concentrado em confinamento, e a sua resposta no desempenho, comportamento ingestivo, componentes não-integrantes da carcaça e características da carcaça e carne. Foram utilizados 33 novilhos, com predominâncias raciais Charolês ou Nelore, com idade e pesos médios inicias, de 20 meses e 269,72 kg de peso vivo. Os animais foram distribuídos ao acaso nos tratamentos, bloqueados conforme predominância genética, e alocados em baias individuais. As dietas foram isonitrogenada, sendo os tratamentos: Casca do grão de soja; Grão de aveia branca e Mistura (partes iguais de casca do grão de soja e grão de aveia branca), acrescidos de calcário calcítico e núcleo proteico. Não ocorreu diferença (P>0,05) entre tratamentos para o consumo de matéria seca (7,42 kg dia-1; 2,23 % PV). Apesar do consumo de matéria seca semelhante, novilhos do tratamento mistura tiveram maior ganho de peso comparados aos do tratamento casca de grão de soja (1,300 vs. 0,972 kg dia-1), porém esses dois tratamentos foram semelhantes ao grão de aveia branca (1,203 kg dia-1). Os animais do tratamento casca do grão de soja mantiveram-se maior tempo em ócio total (1.164 min), comparados aos que receberam a mistura (1.061 min), que por sua vez, permaneceram maior tempo em ócio que os novilhos alimentados com grão de aveia branca (971 min) (P<0,05); para o tempo de ruminação total foi observado comportamento inverso, 69 min; 217 min e 343 min, respectivamente (P<0,05). Os pesos e rendimentos de carcaça quente (65,99%) e fria (64,45%) dos novilhos, expressos em peso de corpo vazio, não foram influenciados pelas dietas (P>0,05). Houve superioridade na quantidade de gordura interna na cavidade abdominal dos novilhos do tratamento grão de aveia branca em relação aos demais (16,22 vs. 20,58 kg; 4,93 vs. 6,15 kg 100 kg-1 de corpo vazio) (P<0,05). O peso absoluto e relativo do conjunto dos órgãos internos e componentes externos dos novilhos foi semelhante (P>0,05). Os novilhos dos tratamentos grão de aveia branca e mistura apresentaram maior volume de sangue em comparação aos da casca do grão de soja (3,53 vs. 2,80 kg 100 kg-1de corpo vazio). As características quantitativas e composição física da carcaça, com exceção do percentual de dianteiro da carcaça, músculo e gordura, não foram afetadas (P<0,05). A implementação de dietas com 100% concentrado são tecnicamente viáveis para novilhos alimentados à base do grão de aveia branca e mistura. O elevado teor de fibra solúvel em detergente neutro no tratamento casca do grão de soja não é suficiente para promover adequado comportamento ingestivo (tempo de ruminação) de novilhos comparado aos demais tratamentos. Dietas exclusivamente com concentrado não influenciam (P>0,05) o peso de corpo vazio de novilhos terminados em confinamento e proporcionam semelhante características qualitativas da carne.
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FONTES DE CARBOIDRATO NO COMPORTAMENTO INGESTIVO DE NOVILHOS CONFINADOS / CARBOHYDRATES SOURCES ON INGESTIVE BEHAVIOR OF STEERSSilva, Viviane Santos da 29 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the influence of different sources of
carbohydrates (corn, soybean hulls and wheat bran) on ingestive behavior of twenty four
steers with initial average of age and weight of 20 months and 330 kg and Charolais or
Nellore predominance. The time spent in feeding activities (214min./day) and total rumination
(458min./day) weren t influenced by diet carbohydrate sources. The animals in the wheat
bran treatment spent less time in total idling (678min.) in relation to the corn (768min./day)
and soybean hulls treatment (774min./day). The neutral detergent fiber (NDF) intake was
higher for the animals fed with soybean hulls and wheat bran (5.18 and 5.42 kg/day
respectively) compared with those who received corn as a carbohydrate source (3.35kg/day),
however the non-fibrous carbohydrates intake was higher for this source of carbohydrate
(4.29kg/day), intermediate for wheat bran (2.53kg/day) and lower for those in soybean hulls
treatment. The steers fed with soybean hulls presented less intake of digestible energy
(27.62Mcal/day) in relation to the corn (35. 5 Mcal/day) and wheat bran (33. 25 Mcal/day)
treatments. Rumination efficiency of NDF was higher for soybean hulls (11.92g/min.) and
wheat bran (10.23g/min.) compared to corn (7.68g/min.). The chewing time per ruminal bolus
was lower for soybean hulls (0.88min./bolus) compared to the diets containing corn
(0.96min./bolus) and wheat bran (0.95min./bolus). The animals with Charolais predominance
presented higher feeding periods (29.41min.) in relation to the steers with Nellore
predominance (24.95min.). The sources of carbohydrates tested didn t influence the feeding
and total rumination time of the animals. The animals with Nellore predominance remain less
time in lying idling, present longer periods of feeding and spend more time in chewing per
ruminal bolus. / Objetivou-se, com este estudo, avaliar a influência de diferentes fontes de carboidratos
(milho, casca de soja ou farelo de trigo) sobre o comportamento ingestivo de 24 novilhos
castrados com idade e peso médio inicial de 20 meses e 330 kg das predominâncias Charolês
ou Nelore. Os tempos despendidos com alimentação (214min./dia) e ruminação total
(458min./dia) não foram influenciados pelas fontes de carboidratos. Os animais do tratamento
farelo de trigo permaneceram menos tempo em ócio total (678min.) em relação ao milho
(768min./dia) e a casca de soja (774min./dia). O consumo da fibra em detergente neutro
(FDN) foi maior para os animais alimentados com casca de soja e farelo de trigo (5,18 e
5,42kg/dia respectivamente) comparado aos que receberam milho como fonte de carboidrato
(3,35kg/dia), no entanto o consumo de carboidratos não-fibrosos foi superior para esta fonte
de carboidrato (4,29kg/dia), intermediário para o farelo de trigo (2,53kg/dia) e inferior para
aqueles do tratamento casca de soja. Os novilhos alimentados com casca de soja apresentaram
menor consumo de energia digestível (27,62 Mcal/dia) em relação aos tratamentos milho
(35,5 Mcal/dia) e farelo de trigo (33,25 Mcal/dia). A eficiência de ruminação FDN foi
superior para a casca de soja (11,92g/min.) e farelo de trigo (10,23g/min.) em comparação ao
milho (7,68g/min.). O tempo de mastigações por bolo ruminal foi menor para a casca de soja
(0,88min./bolo) em comparação as dietas contendo milho (0,96min./bolo) e farelo de trigo
(0,95min./bolo). Os animais de predominância Charolês apresentaram maiores períodos de
alimentação (29,41min.) em relação aos novilhos de predominância Nelore (24,95min.). As
fontes de carboidrato testadas não influenciam o tempo de alimentação e de ruminação total
dos animais. Novilhos de predominância Nelore permanecem menos em ócio deitado,
apresentam períodos de alimentação mais demorados e gastam mais tempo de mastigação por
bolo ruminal.
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Utilização de aditivos na ensilagem de cana-de-açúcar / Use of additivesin silage of cane sugarFreitas, Fernanda Mara Cunha 30 August 2013 (has links)
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Previous issue date: 2013-08-30 / The objective of this work was to evaluate the fermentation characteristics of silage of sugarcane mixed with soybean hulls, bacterial inoculant (L. buchneri) and urea, and their combinations. In addition, intake, milk yield and composition of lactating dairy cows were evaluated. In the first experiment, eight different silages were made using the sugarcane cultivar IAC 86-2480 with the additives: Lactobacillus plantarum/Lactobacillus buchneri (strain NCIMB 40788), urea at the level of 0.5% of the original material and soybean hulls at 10 and 20% of the original fresh material. Eight treatments were tested in mini-silos: pure sugarcane (CN); sugarcane with bacterial inoculant (CNIB); sugarcane with 0.5% urea (CNUR); CNUR + IB (CNIBUR); CNUR + 10% soybean hulls (CNUR10%CS); CNUR + 20% soybean hulls (CNUR20%CS); CNIBUR + 10% CS (CNIBUR10% CS) and CNIBUR + 20% CS (CNIBUR20%CS). The experimental design was a completely randomized with 9 opening periods (1, 2, 3, 7, 15, 30, 60, 120 and 180 days post-closing) with three replicates. We evaluated total, gaseous, and effluent losses as well as the percentages of dry matter, crude protein, neutral detergent (NDF) and acid detergent fiber (ADF). There was no significant effect of bacterial innoculant or urea on silage characteristics: neither pH, dry matter content of silage or gaseous and effluent losses. Urea and bacterial inoculant increased the level of lactic acid and reduced ethanol level (P<0.05) of the silages. The addition of 10 or 20% of soy hulls, by the other side, led to an improvement of silage composition and reduced gaseous and effluent losses, but showed no effect on ethanol or lactic acid of the ensiled sugarcane. In the second experiment, we evaluate the performance of lactating cows fed sugarcane silages with and without soybean hulls or bacterial innoculant. Four lactating cows were randomly assigned to a 4x4 Latin Square design. The experimental treatments tested were: sugarcane silage with bacterial inoculant (CNIB), CNIB with 10% soybean hulls (CNIB10%CS) and CNIB with 20% CS (CNIB20%CS), and a control treatment without additive (CN) pure cane silage (CN). The four experimental periods, lasting 21 days, were splitted into 14 days of adaptation and the following seven days for data collection (milk yield and composition and live weight of the animals). Bacterial inoculant affected negatively dry matter, NDF and protein intake, whereas addition of soybean hulls increase intake of DM, NDF, milk yield and weight gain. The higher the level of soy hulls the higher gain in weight. The inclusion of soy hulls led to weight gain whereas CN or CNIB led to weight losses. It is recommended the addition of soy hulls to the sugarcane chopped material to be ensiled at levels from 10 to 20%. / Objetivou-se com este trabalho avaliar o perfil fermentativo de silagem de cana-de-açúcar aditivada com casca de soja, inoculante bacteriano Lactobacillus buchneri e uréia, em diferentes combinações, além de avaliar consumo e desempenho de vacas lactantes (quantidade e composição do leite produzido). Foram confeccionadas oito silagens diferentes, utilizando a cultivar de cana-de-açúcar IAC 86-2480. Como aditivos foram utilizados: inoculante bacteriano foi o Lactobacillus buchneri (cepa NCIMB 40788), uréia na proporção de 0,5% da matéria original e casca de soja nas proporções de 10 e 20% na matéria original. No primeiro experimento, foram utilizados mini-silos, com oito tratamentos: cana pura (CN); CN + inoculante bacteriano (CNIB); CN com 0.5% uréia (CNUR); CNUR + IB (CNIBUR); CNUR + 10% casca de soja (CNUR10%CS); CNUR + 20% de casca de soja (CNUR20%CS); CNIBUR + 10% CS (CNIBUR10% CS) and CNIBUR + 20% CS (CNIBUR20%CS). O delineamento experimental foi inteiramente casualizado, com 9 períodos de abertura dos silos experimentais (1, 2, 3, 7, 15, 30, 60, 120 e 180 dias pós-fechamento) e 3 repetições. Foram avaliadas as perdas totais, gasosas e por efluentes, além das porcentagens de matéria seca, proteína bruta, fibra em detergente neutro e fibra em detergente ácido. Não foram detectados efeitos do inoculante bacteriano ou uréia sobre as características da silagem, como pH, teor de matéria seca e perdas por efluentes ou gases. Uréia e inoculante bacteriano aumentaram o teor de ácido lático e reduziu o teor de etanol das silagens (P<0,05). A adição de casca de soja, por outro lado, melhorou a composição da silagem com redução nas perdas, mas não afetou os teores de etanol ou ácido lático da cana ensilada. No segundo experimento, foram utilizadas quatro vacas para avaliação da produção de leite e sua composição. Essas foram alimentadas com silagem de cana-de-açúcar com e sem casca de soja, em delineamento experimental quadrado latino 4x4. Os tratamentos foram silagem de cana com inoculante bacteriano (CNIB), silagem de cana com inoculante bacteriano e 10% de casca de soja (CNIB+10%CS) e silagem de cana com inoculante bacteriano e 20% de casca de soja (CNIB+20%CS). O tratamento controle foi silagem de cana pura (CN). Os quatro períodos experimentais, com duração de 21 dias, foram divididos em adaptação (14 dias) e coleta de dados de produção e composição do leite, e mudanças no peso vivo. O inoculante bacteriano afetou negativamente o consumo de matéria seca, de FDN e proteína bruta, enquanto a adição de casca de soja aumentou o consumo de matéria seca, de FDN e a produção de leite. A adição de casca de soja proporcionou ganho de peso, com o nível de 20% superando o nível de 10%. Enquanto a inclusão de casca de soja proporcionou ganho de peso, os tratamentos CN e CNIB levaram a perdas de peso. Recomenda-se a adição de casca de soja a massa a ser ensilada de cana-de-açúcar em níveis entre 10 a 20%.
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