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Hereford cross heifers ( n =3) were slaughtered and hung conventionally. At 1 h post-mortem the M. longissimus dorsi (LD) was excised, vacuum packaged in plastic bags and stored at 4°C. Samples were taken from each of eight different locations along the length of the LD muscle at 1 h, 1, 3 and 15 days post-mortem for extraction using 5% TCA. Supernatants were stored at −20°C until analysis by HPLC. Peptides produced during the storage of beef were isolated by high performance liquid chromatography (HPLC). Results show that these components increase in quantity from 1 h to 15 days post-mortem. Five fractions were collected which correspond to various peaks of interest. These fractions were subsequently analysed by mass spectrometry and amino acid sequencing to reveal their identity. Fractions 1 and 2 were found to be mixtures of low molecular components. Fractions 3, 4 and 5 were found to be proteolytic fragmentation products of glyceraldehyde-3-phosphate dehydrogenase, troponin T and creatine kinase, respectively. Enhanced appearance of proteolytic fragments from these parent proteins with muscle ageing suggest that they may be useful indicators of meat quality. Further work incorporating sensory and/or texture evaluation of muscle tissue is required to investigate this issue

Heifers (n = 70) were slaughtered and hung conventionally in an industrial meat plant. Near infrared (NIR) spectroscopy was studied for its ability to predict selected meat quality attributes, i.e. Warner-Bratzler shear force (WBSF), sensory tenderness, texture, flavour and acceptability. Freshly cut steaks (2.5 cm thick) were taken from the longissimus dorsi (LD) muscle at 1, 2, 7 and 14 days post mortem for NIR analysis. Other samples (also 2.5 cm thick) were taken at 2, 7 and 14 days post mortem, vacuum-packaged in plastic bags and stored at -20 °C for WBSF measurement and sensory analysis. Heifers were slaughtered in two groups; between slaughterings, replacement of the spectrophotometer lamp and lamp assembly was necessitated by a bulb failure. Using principal component regression (PCR), correlation coefficients of 0.82 and 0.73 were obtained for the prediction of WBSF in sample sets 1 and 2, respectively. On merging both sample sets, this value was lowered slightly (r = 0.61). Correlation coefficients obtained for the prediction of tenderness, texture, flavour and acceptability were 0.67, 0.53, 0.51 and 0.46 respectively (set 1); 0.72, 0.71, 0.45 and 0.67 (set 2); 0.53, 0.54, 0.24 and 0.42 (combined sets).

Some results are descibed of an innovative approach for producing net shape polymer, ceramic and carbon composites using wood and other lignocellulose precursors. Wood monoliths have been carbonized without producing cracks as typically found in charcoal materials. These porous carbon monoliths have been readily shaped using standard tools. Conversion to final material has been accomplished without any change in dimensions from the carbon stage, The net-shape materials produced include carbon/epoxy and carbon/carbon composites, silicon carbide, silicon carbide/silicon composites, titanium carbide, and aluminum nitride. Carbonized poplar has been found to be 30% stronger and a carbon/epoxy derived from poplar 250% stronger than the original poplar wood.

This research demonstrated for the first time a method for producing net shape polymer, ceramic and carbon composites using wood as a precursor. The conversion of wood to carbon has been practiced for centuries but the controlled thermal decomposition to form a monolithic carbon to be used as a template for composites as demonstrated by this research is a unique discovery. This was accomplished by thermal decomposition of wood under controlled conditions to produce a crack-free porous carbon monolith which was readily shaped by conventional methods. The shaped carbons have converted to carbon/polymer composites, carbon/carbon composites, ceramics, and ceramic composites without significant changes in dimensions. This research has demonstrated that composites derived from wood can eliminate several expensive processing steps. Specifically, no fiber lay-up or powder consolidation is required, and final grinding and polishing steps are minimized.

By using a combination of very accurately cut wood specimens and highly controlled pyrolysis conditions, we have for the first time obtained precise volumetric and linear shrinkage measurements for wood carbonization which we use to formulate a new theory of cellulose microfibril dominance. Characterization of these crack-free carbonized wood monoliths was performed by measuring density, dimensions, acoustic velocity, yield and crystallinity for heat treatment temperatures ranging from 400 to 2500 °C. Axial dimensions increased at the highest temperatures while radial and tangential dimensions continued to decrease. Acoustic velocity in the axial direction remained constant at 5 mm/μs above 1200 °C. Radial and tangential velocities went through a maximum before diminishing at the highest temperatures. Helium density of powdered carbonized monoliths was found to go through a maximum of 1.9 g/cm3 at 1000 °C before decreasing at the highest temperatures to 1.4 g/cm3, the value obtained for 400 °C char. The experimental results are used to support a model for the relationship between the cellulose molecular arrangement in the wood and the microstructure of the resulting carbon monoliths. It is proposed that cellulose microfibrils dominate the mechanism of dimensional change during pyrolysis and result in a preferred orientation of crystallites in the carbonized wood.

A unique process for conversion of monolithic wood structures to carbons that retain the cellular structure of the wood without the formation of cracks and other defects associated with charcoal materials is described. A variety of wood species are carbonized to produce the materials which are characterized using TGA, density, dimensional changes, acoustic velocity, SEM and mechanical testing. We demonstrate that through controlled pyrolysis monolithic carbonized wood can be produced without the macro-cracks normally associated with charcoal. A linear relationship is established between the bulk densities of wood and carbonized wood which spans the entire range of species. For the conditions presented, the carbonized wood had 82% of the bulk density of the precursor wood. Carbonized wood acoustic velocity ranged from 4.7 to 1.3 mm/μs for Tilia americana and Ochroma pyramidale , respectively. Carbonization resulted in decreased acoustic velocity in the axial principal direction and increases in the radial and tangential directions. Acoustic anisotropy was retained through carbonization, but reduced in magnitude. Mechanical testing showed the carbonized wood to be 28% stronger than the precursor. The cellular morphology of the porous carbonized wood is described and compared to carbon foams.

Heifers (n=47) were slaughtered and hung conventionally in an industrial meat plant. Electrical impedance (Py) and conductivity (EC) were studied for their ability to indicate or predict selected meat quality attributes i.e. Warner-Bratzler shear force (WBSF), sensory tenderness, texture, flavour and acceptability, water holding capacity (WHC) and colour. pH, electrical impedance (meat check) and electrical conductivity (pork quality meter) measurements were taken at hourly intervals up to 8 h and again at 1 and 2 days postmortem. Electrical measurements were taken again at 7 and 14 days postmortem. Freshly cut steaks (2.5 cm thick) were taken from the longissimus dorsi (LD) muscle at 2, 7 and 14 days postmortem, vacuum-packaged in plastic bags and stored at -20°C for WBSF and sensory analysis. Freshly cut steaks were used for WHC and colour measurements. During the development of rigor and over the ageing period, electrical changes occur in muscle tissue. Electrical measurements were found to change significantly between 1 and 14 days postmortem and when measured over the ageing period (at 2, 7 and 14 days postmortem) were significantly correlated to WBSF, sensory tenderness and Hunter 'a' and 'b' values (r=±0.56-±0.68, p

Fiber reinforced polymer composites have become quite popular in recent years and have been used for a wide variety of applications ranging from sports equipment to advanced aircraft components. There has recently been considerable interest in the behavior of thick composite laminates under compressive loadsl. This interest stems from the development of novel materials for applications in submersed vessels. A submersible vessel hull is one of the few structures in which the material would experience nearly pure compressive loads. For a structure which is designed to be brought to the depths normally encountered by submarines, a skin of material several inches thick is required. In order to utilize composites for this purpose research into the compressive strength and fatigue life of these materials is needed. In addition, in service inspection techniques must be developed to assess the integrity of such a structure.

There has recently been considerable interest in the behavior of thick section (one inch and greater) polymer composites under compressive loads [1]. Strength, fatigue life and damage modes are characteristics which design and inspection engineers seek to understand to properly utilize these materials in applications where compressive loads are encountered. This paper presents a brief summary of some of the progress in a research effort to characterize the compression-compression fatigue behavior of thick section fiber reinforced polymer composites. Primary objectives of this research are to determine fatigue life and strength, and to use nondestructive techniques to predict material failure with particular interest in identifying the early stages of damage. Destructive techniques are implemented to correlate actual damage mechanisms to any “fingerprint” found by NDE methods. Specifically, one inch thick, double edge notched, graphite epoxy coupons were fatigued to failure while structural stiffness and acoustic emissions were monitored. Unfailed specimens were examined using ultrasonic C-scan and X-ray radiography after which they were cut and polished for damage identification via microscopy.