Recent results of fracture experiments on carbon steel welded pipes

Several pipe fracture experiments were conducted with circumferential cracks in the center of ferritic nuclear pipe welds. These experiments involved either submerged arc or shielded metal arc welds with either through-wall cracks or internal surface cracks. The pipe diameters varied from 940 mm (37 inches) to 152 mm (6 inches), and thickness from 10·9 mm (0·43 inches) to 86·6 mm (3·41 inches). Some of the through-wall and surface-cracked pipe experiments were conducted under constant internal pressure and four-point bending. The test temperature was 288°C (550°F). The results of these experiments are compared with limit-load analyses, the ASME, Section XI, article IWB-3650 criterion, and more elaborate elastic-plastic fracture mechanical analysis.     

Investigation of the Impacts of Gamma Radiolysis on an Advanced TALSPEAK Separation

The advanced TALSPEAK process is a selective solvent extraction that utilizes 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) to separate lanthanide elements from trivalent actinides, which are held back in the aqueous phase by N-hydroxylethyl-N,N’,N’-ethylenediamine triacetic acid (HEDTA) buffered by citric acid. Gamma irradiation of an experiment containing Eu(III) and Am(III) as representative lanthanide and actinide elements resulted in higher distribution ratios of both and separation factors which decreased in an exponential fashion with increasing dose. Analysis of the reagents showed that the HEDTA concentration also decreased in an exponential fashion, strongly suggesting that degradation was correlated with loss of separation selectivity. In contrast, the concentration of citrate was unaffected, and while the concentration of HEH[EHP] did decrease, its dose-dependent kinetic profile indicated that it was not limiting partitioning. A second set of experiments were conducted using a citrate concentration that was 7.5 X higher, with the expectation that citrate would protect the HEDTA by scavenging radiolytically formed OH radicals. HEDTA degradation was significantly mitigated at higher gamma doses, but the Eu-Am separation was worse than in the low citrate experiments, presumably because at the high citrate concentrations, the Eu-citrate complexes formed in abundances competitive with the Am complexes, and are more effectively held back in the aqueous phase.     

Fractionation of non-Brownian rod-like particle suspensions in a viscoplastic fluid

In this work we explore a fractionation technique for non-Brownian rod-like particle suspensions based upon the control of the threshold for motion in a yield stress fluid. The principle is demonstrated by observing the motion of particles under the influence of a centrifugal force in a weak gel. Here we develop calibration curves of the force required to initiate motion in a gel under numerous configurations of the particles. Demonstration separations of bidisperse suspensions are reported. Here we achieve complete separation of dilute suspensions based upon length, diameter, or density. The method is then applied to an industrially important suspension, that is a polydispersed papermaking fibre suspension, in which a length-based fractionation is reported.     

Limitations of classical methods for measuring surface tension in visco-elastic liquids

The surface tension of a water/detergent mixture and a visco-elastic waterborne paint sample were measured using the classical ring method in which a thin free liquid film (lamella) is formed between the ring and the parent liquid. Lamella tension was measured during the stretching of the lamella. Measurements of water/surfactant mixtures have shown essentially classical behavior of lamella tension (independence of tension on deformation). Measurements of a waterborne paint formulation, however, have shown that after stretching of the lamella, the lamella tension decreases. The lamella tension of the paint sample increases after contraction of the lamella. Comparison of experimental results with rheological properties of the paint have shown that bulk visco-elastic properties of liquid are found in both the bulk sample and the lamella. The conclusion is that for the study of surface properties of visco-elastic liquids such as waterborne paints, the applicability of classical methods is limited. Therefore, it was necessary to develop new methods and approaches to study the properties of these materials. These methods are described in this paper.     

Growth rates of Salmonella and Escherichia coli O157:H7 in irradiated beef.

Ground beef was irradiated to 0, 2, or 4 kGy and then inoculated with a mixed culture of four serotypes of salmonellae or five strains of Escherichia coli O157:H7. The ground beef was stored at either 15 or 25 degrees C, and the growth of the inoculated bacteria was monitored over time. Growth parameters were determined for both the salmonellae and the E. coli O157:H7 using the Gompertz equation. There was no significant difference in lag phase duration or generation time, irrespective of the dose to which the ground beef had previously been exposed. Furthermore, the lag phase durations and generation times determined in this study did not differ significantly from previously published values. This suggests that, although irradiation eliminates a significant portion of the spoilage microflora in ground beef, the absence of this microflora provides no competitive advantage to the growth of salmonellae or E. coli O157:H7 in ground beef.     

Supporting Scientific Collaboration: Methods, Tools and Concepts

This paper discusses the interrelationship between e-Science and CSCW in terms of key substantive, methodological and conceptual innovations made in both fields. In so doing, we hope to draw out the existing relationship between CSCW and e-Science research, and to map out some key future challenges where the two areas of research may become more closely aligned. In considering what may be required to draw the two more closely together, the paper focuses primarily on investigations that have been undertaken in two dedicated initiatives into e-Science, along with the key issues emerging from these studies.     

Commentary: Esophageal carcinoma confined to the wall--the need for immediate definitive therapy

Twenty-six Holstein calves with clinical and pathological effects suggesting a toxic plant intoxication were studied. A view of the plants in the region and blood examination (hemogram, albumin, total protein, calcium and phosphorus) and determination of bone calcium were done. Five calves were slaughtered and pathological examinations were performed. Observed metabolic, pathological and clinical alterations were compatible with intoxication from Cestrum diurnum.     

Le bâtiment et les exportations

La récession que connaît le bâtiment dans la plupart des pays industrialisés occidentaux a obligé leurs industriés de la construction à chercher de nouveaux marchés à I'étranger. L'auteur, un des associés de la société d'ingénieurs-conseils en génie civil Kjessler et Mannersträle, SA de Stockholm nous donne une idée de la situation en Suède et des possibilités qu'elle présente pour les consultants à I'étranger.     

Volatiles Production and Lipid Oxidation in Irradiated Cooked Sausage as Related to Packaging and Storage

Irradiation dose affected production of volatiles in vacuum-and aerobic-packaged cooked pork sausage, but its effect on TBARS was minor. Storage increased production of volatiles and changed their composition only in aerobic-packaged sausage. Among volatile components, 1-heptene and 1-nonene were influenced most by irradiation dose, and aldehydes by packaging type. TBARS and volatiles of vacuum-packaged irradiated cooked sausage did not correlate well. However, TBARS had very high correlation with amount of aldehydes, total volatiles, ketones and alcohols with long retention times in aerobic-packaged pork sausage. Heptene and 1-nonene could be indicators for irradiation; and propanal, pentanal, and hexanal for oxygen-dependent changes of cooked meat.