Earthen constructions can experience severe damage under coupled action of moistening and freezing-thawing (F-T). This paper proposes an experimental study on the F-T behavior earthen samples at different liquid saturation degrees (SL0). Normal moisture conditions during winter were investigated using two values relative humidity (RH): RH = 75% 95% which led to levels lower than 35% for tested ...

The network structure of poly(vinyl alcohol) (PVA) hydrogels obtained by freezing-thawing cycles was investigated by solid-state (1)H low-field NMR spectroscopy. By the application of multiple-quantum NMR experiments, we obtain information about the segmental order parameter, which is directly related to the restrictions on chain motion (cross-links) formed upon gelation. These measurements ind...

In a recent review on the storage of animal viruses at subzero temperatures (8), it was pointed out that enveloped viruses present special problems. For example, herpesvirus even at -90 C loses infectivity after prolonged storage and at -20 C is even more labile than at 4 C. Repeated freezings and thawings of this virus result in marked loss in activity. Members of the herpesvirus group can be ...

Polyacrylonitrile (PAN) gel was prepared by the freezing and thawing method using the solvents of N,N-dimethylacetamide (DMA) and tetramethylene sulfone(sulfolane). The gelation time after a series of freezing and thawing was examined with varying PAN concentration of DMA solution and the freezing time. Dynamic viscoelasticity was measured in the course of gelation for DMA solution to observe t...

Clenbuterol is a well-known growth promoter, illegally used in farm animals, especially in cattle. Samples collected for the screening of beta(2)-agonist residues in Portuguese Azores Islands must travel through all the nine islands until they reach Azores Central Laboratory. If any suspicious sample is detected, it must be further transported to the National Reference Laboratory in Lisbon for ...

This study examined shape changes in two typical wastewater flocs subjected to cyclic freezing and thawing and the associated force exerted by the ice front. While freezing, the engulfing ice front gradually pulled the floc apart. Subsequent thawing only partially restored the floc's shape. By the Maxwell model, used to interpret gross shape deformations, both flocs were visco-elastic objects e...

the use of various slags as by-products of steel industry is well established in civil engineering applications. however, the use of bos slag in the area of soil stabilization has not been fully researched and developed despite having similar chemical composition and mineralogy to that of portland cement. this paper reports on efforts to extend the use of bos slag to soil stabilization by deter...

Very little is known about the capacity of soil chytrids to withstand freezing in the field. Tolerance to freezing was tested in 21 chytrids isolated from cropping and undisturbed soils in temperate Australia. Samples of thalli grown on peptone-yeast-glucose (PYG) agar were incubated for seven days at -15 degrees C. Recovery of growth after thawing and transferring to fresh medium at 20 degrees...