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101.
A meshfree numerical method for the dynamic analysis of porous media is presented. The u,?p form of Biot’s theory is adopted to mathematically model the dynamic interaction of the solid and the fluid phase within the porous media. The obtained partial differential equations (PDEs) are discretized by the generalized smoothed Galerkin weak form, which is established based on smoothed strains and fluxes. Therefore, edge-based and cell-based smoothing domains are used and a T3-scheme is employed for the selection of support nodes. The shape functions are generated by the radial point interpolation method. The focus of this work lies on the spatial integration of the mass/compressibility and coupling terms of the discrete PDE system. A new algorithm is introduced, which reuses the shape function values that are needed for the construction of the stiffness/permeability matrix to keep the computational effort at a minimum. Numerical problems are analyzed in order to test the algorithm regarding accuracy and efficiency. 相似文献
102.
J.R. Arruda K. Marti C.M. Mota Soares E.S. Mistakidis G.I. Schuëller M. Papdrakakis B.H.V. Topping 《Computers & Structures》2011,89(19-20):1727-1729
103.
Ana Paula R. Harbach Mara C.R. da Costa Adriana L. Soares Ana M. Bridi M. Shimokomaki Caio A. da Silva Elza I. Ida 《Food chemistry》2007,100(4):1630-1633
The effects of dietary defatted corn germ meal (DCGM) containing phytic acid (PA) on pig health during development and on its Longissimus dorsi m. (LD) lipid oxidative stability has been evaluated. Rations of DCGM were prepared at the level of substitution of 0%, 10%, 20% and 40% and offered to twenty four animals of Landrace x Large White crossbreds throughout 25 days before slaughtering. Animals were sacrificed at an average weight of 91.24 kg (±0.950) and samples for meat lipid oxidation analysis were taken after seven days under refrigeration at 3 °C. Animals fed with DCGM did not show any significant difference, in comparison to the control, in carcass characteristics, such as cold carcass weight, backfat depth, muscle depth, lean meat percentage and carcass dress yielding (p 0.05). Finally, no difference in meat proximate chemical composition was detected solely arising from lipid oxidation since LD from DCGM-treated pigs revealed an inhibition of 63.0%. 相似文献
104.
Soares Carlos R.J.; Gomide Fernanda I.C.; Ueda Eric K.M.; Bartolini Paolo 《Protein engineering, design & selection : PEDS》2003,16(12):1131-1138
The influence of different factors acting on Escherichia coliperiplasmic expression of recombinant human growth hormone (hGH)in shake flask cultures has been investigated. Bacterial vectorscontaining the phage 相似文献
105.
A study of the design and mechanical behaviour of co-cured T-beams subjected to lateral loading on the web is presented. The T-beams were manufactured by press moulding from pre-pregs of uni-directional and fabric glass reinforced high performance epoxy matrix. A special fixture was designed in order to carry out tests where the T-beams were laterally loaded on the web and clamped on the flange. Analytical and numerical studies were performed to predict the failure load to compare with the experimental results. The multilayer anisotropic continuum theory for delamination analysis of curved beams subjected to end moments and forces was used to compute the delamination stresses in the quarter cylindrical beam of the junction between the flange and the web. Finite element analyses of the T-beams were performed using plate/shell elements and two models were used for the joining between web and flange, to compute the planar stresses in the beam. The scatter obtained in the experimental results can be explained by the presence of two failure modes: one due to delamination associated with the through the thickness stresses developed in the curved part of the beam, the other related with failure occurring due to tangential stresses in the most highly stressed plies. 相似文献
106.
RS Jesuino Rde B Soares SM Salem-Izacc M Pereira MS Felipe CM Soares 《Canadian Metallurgical Quarterly》1997,41(2):93-99
The reversed dermal graft has been employed in reconstructive plastic surgery for almost 80 years. It is recommended that the dermatologic surgeon use this graft technique whenever a case calls for the combined advantages of the split-thickness skin graft for poorly vascularized areas and the axial pedicle flap appropriate to areas subject to marked mechanical strain. We present cases in which defects on the scalp, sole, palm, and great toe have been covered by reversed dermal graft and split-thickness skin graft in a single operation with excellent results. Our modification of the technique has proved that simultaneous grafting with reversed dermis and split-thickness skin graft produces satisfactory results, reduces postoperative care by 2 weeks, and obviates repeated anesthesia. 相似文献
107.
Identification and field evaluation ofAnomala octiescostata (Coleoptera: Scarabaeidae) sex pheromone
Walter Soares Leal Makoto Hasegawa Masaaki Sawada Mikio Ono Yasuo Ueda 《Journal of chemical ecology》1994,20(7):1643-1655
Using GC-EAD, the sex pheromone of the scarab beetleAnomala octiescostata was identified to be a 8:2 binary mixture of (R,Z)-5-(–)-(oct-1-enyl)oxacyclopentan-2-one and (R,Z)-5-(–)-(dec-1-enyl)oxacyclopentan-2-one. These semiochemicals have been also reported as sex pheromone constituents of otherAnomala species, either geographically or seasonally isolated fromA. octiescostata. Synthetic sex pheromone was highly attractive in the field; 0.1 mg captured significantly more males than two virgin females. Buried traps were significantly more attractive than those positioned at 30, 90, and 150 cm above the ground. In a dose-response test (0.1–100 mg), no saturation due to overdose of pheromone was observed, but in most cases, two dosages differing by 10-fold were not significantly different. Response of males to traps baited with different ratios of the two components was tested in two experiments with randomized blocks and Latin-square designs. Deviation from the natural ratio (8:2) of sex pheromone did not significantly diminish the response of males. Peak flight activity of beetle was recorded at 9:00–10:00 AM JST on sunny days in the end of April 1993.Presented in part at the 10th Annual ISCE Meeting, July 31–August 4, 1993, Clearwater Beach, Florida. 相似文献
108.
This paper presents a discrete model for the sensitivity analysis and optimization of thin, multi-layered, angle-ply composite structures. The model is based on a plate-shell element with 18 degrees of freedom, using the discrete Kirchhoff theory for the bending effects. Angle-ply design variables and vectorial distances from the middle surface to the upper surface of each layer (indirectly, the thickness) are considered as design variables. Different objectives and constraints can be used as a specified displacement or the structure elastic strain energy or the volume of structural material or a chosen natural frequency or buckling load parameter. The design sensitivities are evaluated analytically. The efficiency and accuracy of the model developed is discussed with reference to several applications. 相似文献
109.
Polymeric supports based on divinylbenzene (DVB) were prepared by aqueous suspension polymerization in presence or absence of styrene (S), using toluene and n‐heptane as diluents of the monomers. Poly(S–DVB) and poly(DVB) were sulfonated with sulfuric acid in presence of 1,2‐dichloroethane. The influence of the morphological structure of the supports and as a consequence of the catalyst on the esterification reaction of acetic acid with n‐butanol was evaluated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3616–3627, 2006 相似文献
110.
A formulation is presented to account for the effect of corrosion and fatigue on the reliability of ship hulls. A time variant formulation is presented in which the effect of these degradation phenomena on the hull section modulus is quantified. The effect of maintenance actions is accounted for by considering that the repaired elements are restored to a state as new. Different repair policies can be studied and the approach can be used as a tool to plan the maintenance actions based on reliability results. 相似文献