Evaluación de pollitas Hy-Line variedad Brown, en etapa de inicio a rompimiento de postura, bajo manejo tradicional

Se evaluó el comportamiento productivo de pollitas Hy- Line var. Brown, durante las primeras diecisiete semanas de desarrollo con la guía de manejo comercial para estas aves. Se utilizó un lote de 4,591 aves distribuidas en dos galeras. Se muestreó el 4% de la población de forma aleatoria y sin reemplazo, registrando peso, alimento consumido y mortalidad. Se realizaron los cálculos de consumo, uniformidad de peso, mortalidad de lote y se registraron las prácticas sanitarias de la granja. El consumo total obtenido fue un 15.6% inferior al reportado por la guía de manejo (803 g), viéndose afectado por cambios en el manejo del alimento, el que fue suministrado de acuerdo al peso vivo y no a la edad de las aves. El peso de las aves resultó 9.3% inferior al estipulado por la guía de manejo. La uniformidad del lote fue del 80% con una variación de ±10% igual al esperado para este tipo de aves. La mortalidad de la granja fue inferior al 0.04% expresado por la guía de manejo comercial. La aplicación del plan sanitario sufrió alteración en el tiempo de ejecución, sin embargo no tuvo efecto sobre la mortalidad de la granja. El manejo zootécnico de la granja está dentro de lo esperado en granjas de pequeños productores avícolas en condiciones tropicales.

扩散处理热浸镀铝钢高温抗氧化行为的研究

On-line observation of interlaminar damage by ultrasonic inspection

This paper explores an on-line experimental method to highlight the process of internal damage development in composites by taking advantage of ultrasonic inspection. A loading device, which can work together with an ultrasonic inspection system, was designed, and the interlaminar shear damage of a double-sided grooved specimen of composite was examined on-line with the system. A full view of the progressive internal interlaminar damage, seen only with difficulty by common inspection methods, was successfully achieved.

First human hNT neurons patterned on parylene-C/silicon dioxide substrates: Combining an accessible cell line and robust patterning technology for the study of the pathological adult human brain

In this communication, we describe a new method which has enabled the first patterning of human neurons (derived from the human teratocarcinoma cell line (hNT)) on parylene-C/silicon dioxide substrates. We reveal the details of the nanofabrication processes, cell differentiation and culturing protocols necessary to successfully pattern hNT neurons which are each key aspects of this new method. The benefits in patterning human neurons on silicon chip using an accessible cell line and robust patterning technology are of widespread value. Thus, using a combined technology such as this will facilitate the detailed study of the pathological human brain at both the single cell and network level. © 2010 Elsevier B.V.

Improved Analysis Method for Wave-Induced Pipeline Stability on Sandy Seabed

The existing Det Norske Veritas DNV Recommended Practice RP E305 for pipeline on-bottom stability is mainly based on the pipe–soil interaction model reported by Wagner et al. in 1987, and the wake model reported by Lambrakos et al. in 1987, to calculate the soil resistance and the hydrodynamic forces upon pipeline, respectively. Unlike the methods in the DNV Practice, in this paper, an improved analysis method is proposed for the on-bottom stability of a submarine pipeline, which is based on the relationships between Um/ gD 0.5 and Ws / D2 for various restraint conditions obtained by the hydrodynamic loading experiments, taking into account the coupling effects between wave, pipeline, and sandy seabed. The analysis procedure is illustrated with a detailed flow chart. A comparison is made between the submerged weights of pipeline predicted with the DNV Practice and those with the new method. The proposed analysis method may provide a helpful tool for the engineering practice of pipeline on-bottom stability design.

Asymptotic analysis based on K-S constitutive law for a rubber wedge compressed by a line load at its tip

In the present paper, a rubber wedge compressed by a line load at its tip is asymptotically analyzed using a special constitutive law proposed by Knowles and Sternberg (K-S elastic law) [J. Elasticity 3 (1973) 67]. The method of dividing sectors proposed by Gao [Theoret. Appl. Fract, Mech. 14 (1990) 219] is used. Domain near the wedge tip can be divided into one expanding sector and two narrowing sectors. Asymptotic equations of the strain-stress field near the wedge tip are derived and solved numerically. The deformation pattern near a wedge tip is completely revealed. A special case. i.e. a half space compressed by a line load is solved while the wedge angle is pi.

An Improved Ce/Se Scheme And Its Application To Detonation Propagation

An improved two-dimensional space-time conservation element and solution element ( CE/ SE) method with second-order accuracy is proposed, examined and extended to simulate the detonation propagations using detailed chemical reaction models. The numerical results of planar and cellular detonation are compared with corresponding results by the Chapman-Jouguet theory and experiments, and prove that the method is a new reliable way for numerical simulations of detonation propagation.

An In-Situ Observation On Initial Aggregation Process Of Colloidal Particles Near Three-Phase Contact Line Of Air, Water And Vertical Substrate

The self-assembling process near the three-phase contact line of air, water and vertical substrate is widely used to produce various kinds of nanostructured materials and devices. We perform an in-situ observation on the self-assembling process in the vicinity of the three phase contact line. Three kinds of aggregations, i.e. particle-particle aggregation, particle-chain aggregation and chain-chain aggregation, in the initial stage of vertical deposition process are revealed by our experiments. It is found that the particle particle aggregation and the particle-chain aggregation can be qualitatively explained by the theory of the capillary immersion force and mirror image force, while the chain-chain aggregation leaves an opening question for the further studies. The present study may provide more deep insight into the self-assembling process of colloidal particles.

An Improved Energy Method For Determining Young'S Modulus By Instrumented Indentation Using A Berkovich Tip

We previously proposed a method for estimating Young's modulus from instrumented nanoindentation data based on a model assuming that the indenter had a spherical-capped Berkovich geometry to take account of the bluntness effect. The method is now further improved by releasing the constraint on the tip shape, allowing it to have a much broader arbitrariness to range from a conical-tipped shape to a flat-ended shape, whereas the spherical-capped shape is just a special case in between. This method requires two parameters to specify a tip geometry, namely, a volume bluntness ratio V-r and a height bluntness ratio h(r). A set of functional relationships correlating nominal hardness/reduced elastic modulus ratio (H-n/E-r) and elastic work/total work ratio (W-e/W) were established based on dimensional analysis and finite element simulations, with each relationship specified by a set of V-r and h(r). Young's modulus of an indented material can be estimated from these relationships. The method was shown to be valid when applied to S45C carbon steel and 6061 aluminum alloy.