MOTTLED SILICA BRICK,FACTS, FANCIES,AND FALLACIES*

The extent of coloration is dependent on the amount of lime and alumina and on the thermal history. The coloring agent is usually iron oxide which is present in small amounts. Color is dependent on the grind and on the mixing, drying, and burning procedures. The color can be cleared up or accentuated by controlled laboratory reheating at known temperatures, for definite time intervals. The mottling does not appear unless the brick are well burned. The spots, moreover, have no harmful effect. The literature on this subject is reviewed.     

The Organization of Product Development

This paper develops a critical perspective on the theory underlyingcontemporary product development practice. It contrasts whatis today the dominant approach to design and product development,an approach that is analytical and problem-oriented, with analternative approach that is interpretative and process-oriented.The interpretative approach views product development as enteringinto an ongoing process in which people are already engaged.It sees the interactions between the different communities involvedin product development as a set of ongoing conversations. Itsuggests the need for a set of conceptual tools for managingthis process which are quite distinct from those associatedwith the analytical approach.     

Effect of ZrO2 Inclusions on the Sinterability of Al2O3

The sinterability of Al₂O₃/ZrO₂ composite powder compacts containing 2 and 10 vol% ZrO₂ was compared to the sinterability of their single-phase constituents through constant-heating-rate experiments. The ZrO₂ inclusion phase delayed the initiation of bulk shrinkage and the temperature of maximum strain rate by 100°C. The ZrO₂ inclusion phase also significantly inhibited grain growth. These results, discussed with regard to the thermodynamics of pore disappearance, suggest that phenomena inhibiting grain growth may also inhibit densification.     

EFFECT OF PBAN ON PHEROMONE PRODUCTION BY MATED <Emphasis Type="Italic">Heliothis virescens</Emphasis> AND <Emphasis Type="Italic">Heliothis subflexa</Emphasis> FEMALES

Mated female Heliothis virescens and H. subflexa were induced to produce sex pheromone during the photophase by injection of pheromone biosynthesis activating neuropeptide (PBAN). When injected with 1 pmol Hez-PBAN, the total amount of pheromone that could be extracted from glands of mated females during the photophase was similar to that extracted from virgin females in the scotophase. The PBAN-induced profile of pheromone components was compared between mated, PBAN-injected females and virgin females during spring and fall. Virgin females exhibited some differences in the relative composition of the pheromone blend between spring and fall, but no such temporal differences were detected in PBAN-injected, mated females. Because the temporal variation in pheromone blend composition was greater for virgin females than for PBAN-injected females, PBAN can be used to determine a females native pheromone phenotype. This procedure has the advantages that pheromone glands can be extracted during the photophase, from mated females that have already oviposited.     

Model for Ion-Exchanged Waveguides in Glass

An analytical model describing refractive index profiles in ion-exchanged glass waveguides is presented. Polarizability, volume, and stress-state changes are accounted for. Index distribution is given in terms of known or measurable physical parameters. Model predictions compare favorably with experimental results of field-assisted ion-exchanged waveguides fabricated in 7740 borosilicate glass. Experimental characterization of the index changes includes prism coupling, microprobe, and photoelastic measurements.     

On the Fourier transform of sequency limited signals with applications to delta modulation and medicine†

It is the binary nature of the Walsh basis functions that make the Walsh transform a potentially useful signal processing tool. Unlike the FFT, which produces a database in the easily interpreted frequency domain, a Walsh data base resides in the obscure sequency domain. Using a fast Walsh algorithm, an N-point transform can, however, be computed more rapidly than a FFT using a similar computer architecture. Even though the sequency space has been shown to be useful in coding and picture processing applications, the aperiodic behaviour of its basis functions make it. unsuitable for many traditional signal-processing problems. It would be desirable, for example, to be able to relate the computationally efficient Walsh spectra to the intuitively pleasing Fourier spectra. This work will address that problem and present new results.     

Ranking multicritena fuzzy alternatives in the decision-maker's preference subspace

This paper offers a new procedure for ranking multicritena fuzzy alternatives when the decision-maker subscribes to the notion of ‘the larger, the better’. For each alternative a joint membership function captures possible interactions among ratings for each criterion. The ranking procedure first orthogonally projects the joint membership functions from the multicritena decision space to the one-dimensional preference subspace, and then the fuzzy projections are ranked in that subspace. A method for generating joint membership functions is introduced, and a numerical example is presented.     

EFFECT OF TOTAL LIPIDS, TRIACYLGLYCEROLS AND PHOSPHOLIPIDS ON MALONALDEHYDE CONTENT IN DIFFERENT TYPES OF CHICKEN MUSCLES AND THE CORRESPONDING SKIN

Total lipid extracted from chicken breast, thigh, drumstick and wing muscles and the corresponding skin was analyzed for triacylglycerols and phospholipids as well as their fatty acid composition and also for malonaldehyde and lipid oxidation fluorescent products (LOFP) content.
Muscles consist of only 1.2–3.2% lipid, but lipid concentration in the skin ranges from 22.2–31.7%. The percentage of phospholipid in muscle lipid was 20 times more than that of the skin. The fatty acids of triacylglycerols from muscles and skin contained less than 2% of polyunsaturated fatty acids (PUFA). Fatty acids from phospholipid of the meat contained over 15% arachidonic acid and substantial amounts of PUFA with 22 carbon atoms. Skin phospholipid had 10.6–13.2% of all PUFA.
Differences in the lipid composition of muscles and skin resulted in a concentration of malonaldehyde in muscle lipids of 30–50 mg/g, a value more than 15 times greater than in lipids of the skin. However, the TBA number of the skin was the same or a little bit lower as compared to muscles. The relative levels of LOFP in the organic phase of Folch-extracted muscle and skin tissues paralleled the trend found for malonaldehyde concentrations.
It was concluded that the simultaneous determination of total lipid content and malonaldehyde concentration in lipid extracted from various chicken muscles and corresponding skin was the most informative method for evaluation of precursors of lipid oxidation in fresh tissue.     

Investigation of the System CaO-MgO-V2O5: I, Phase Equilibria

The ternary subsolidus phase equilibria were determined for the system CaO-MgO-V₂O₅. Limits of crystalline solubility were determined along the meta- and orthovanadate joins. The metavanadate join was characterized as two large solution regions with the end-members as host structures separated by a small two-phase region. The orthovanadate join was characterized as a small solution region in the center with the defect garnet structure. Eighteen compatibility triangles were found to make up the proposed subsolidus equilibrium diagram.