Quantitative nuclear magnetic resonance was used to measure the freezing behaviour of lamellar phases of phosphatidylcholine in water and in solutions of sorbitol. Both solute and solvent were deuterated in different series of experiments to allow the calculation of the partitioning of solute and solvent molecules between the lamellar phase and unfrozen bulk solution. Sorbitol, as well as water...

Two new species of oribatid mites of the genus Pergalumna (Oribatida, Galumnidae), P. elongatiporosa sp. n. and P. striatiprodorsum sp. n., are described from leaf litter of a secondary forest in Costa Rica. Pergalumna elongatiporosa sp. n. is most similar morphologically to P. horvathorum P. Balogh, 1997 and P. sura P. Balogh, 1997, however, it differs from both by the body size, body surface ...

The interlamellar biomechanical properties of stromal collagen are relatively unknown, yet may be highly significant with respect to wound healing and the efficacy of certain keratorefractive surgical procedures. Interlamellar adhesive strength was measured as the tearing force required to separate corneal lamellae at a 50% stromal depth in 16 human eyebank corneas. The mean value for the centr...

This research studied the application of the response surface methodology (RSM) and central composite design (CCD) experiment in mathematical model and optimizes postweld heat treatment (PWHT). The material of study is a pressure vessel steel ASTM A516 grade 70 that is used for gas metal arc welding. PWHT parameters examined in this study included PWHT temperatures and time. The resulting mater...

Grain refinement through severe plastic deformation enables synthesis of ultrahigh-strength nanostructured materials. Two challenges exist in that context: First, deformation-driven grain refinement is limited by dynamic dislocation recovery and crystal coarsening due to capillary driving forces; second, grain boundary sliding and hence softening occur when the grain size approaches several nan...

The aim of the present research is to simulate the heat treatment process of the autogenous grinding (AG) shell liner of Cr-Mo steel in different quenching media (still air, air blowing, oil and water) using ABAQUS software, in order to calculate the cooling curves. In this regard, the microstructure and hardness for each arbitrary point within the mill liner's bulk could be predicted based on ...

The process of re-crystallization in poly(ethylene terephthalate) is studied by means of X-ray diffraction (SAXS and WAXS) and dynamical mechanical thermal analysis. Samples cold-crystallized for 9h at the temperatures T(c) = 100°C and T (c) = 160°C, i.e. in the middle of the alpha relaxation region and close to its upper bound, respectively, are analyzed. During heating from room temperature, ...

To understand the cellular basis of learning and memory, the neurophysiology of the hippocampus has been largely examined in thin transverse slice preparations. However, the synaptic architecture along the longitudinal septo-temporal axis perpendicular to the transverse projections in CA1 is largely unknown, despite its potential significance for understanding the information processing carried...