A new type of Langmuir trough was constructed in which temperature of the water surface is controlled precisely according to a program using a large number of Peltier elements and a microcomputer. We can suppress convection of the water in the trough during linear heating or linear cooling by planning the trough as thin as 2 mm. This trough is very suitable for measuring A-T isobars and π- T isochores of insoluble monolayers which are rarely measured precisely. The newly developed trough can permit observation of Brewster angle microscopic (BAM) images of insoluble monolayers clearly during measurements of A-T isobars by suppressing convection completely.
Evaporation of a liquid droplet of aqueous solutions of slightly soluble electlytes such as CaCO3, CaSO4, and KIO4 and of concrete-soaked-rain water and concrete-soaked-distilled water on untreated and surface-treated glass plate has been investigated through the measurement of bottom length and contact angle of the liquid droplet against time. The deposition of the solute after evaporation has also been investigated. The contact angle decreased at a constant bottom length during the evaporation of a droplet on untreated glass plates. The solute deposited on the edge of the droplet and showed a caldera-like ring after complete evaporation. On the other hand, contact angle decreased to a limited value θR at a constant length of bottom of a droplet on the hydrophobic surface of glass plate with low surface energy and afterwards the length of bottom of a droplet decreased at a constant contact angle, θR during its evaporation. A crystalline agglomerate smaller than that of the initial liquid droplet was deposited after complete evaporation.
Accurate prediction of contact behaviour between machine tools and metals is required for the mechanical design of machinery. In this article, the numerical analysis of the contact behaviour is described by incorporating the subloading-overstress model [6] which is capable of describing the contact behaviour for a wide range of sliding velocity including the increase of coefficient of friction with the increase of sliding velocity. And its validity is verified by the comparison with some test results. First, in order to examine the influence of sliding velocities on the friction properties, the flat-surface friction tests for lubricated interfaces between galvannealed steel sheet and SKD-11 tool steel were performed. As a result, It is observed that the friction smoothly translate to kinetic friction, after exhibiting the peak at the static friction. In addition, it is observed that the higher the sliding velocity, the larger the friction resistance, meaning the positive rate sensitivity. Then the subloading-overstress model is implemented in the finite element analysis program ABAQUS/Standard, and it is used to simulate the flat-surface friction tests. The predictions from the finite element analysis are shown to be in very good agreement with experimental results.
In this work, a new approach that utilizes CaO-loaded microcapsules as microreactor for biodiesel production is proposed. CaO was encapsulated in amphiphilic alginate by coextrusion technique. When CaO-loaded microcapsules were used, the transesterification of rapeseed oil with methanol gradually proceeded with time, indicating that both oil and methanol passed through the microcapsule shells and the transesterification catalyzed by CaO powder occurred inside the microcapsules. Moreover, the utilization of CaO-loaded microcapsules as a solid base catalyst considerably made the initial induction period shortened and significantly suppressed the dissolution of Ca ion in the reaction mixture rather than CaO powder. The results of reusability tests showed that CaO-loaded microcapsules could be easily separated from the reaction mixture and recycled three times without significant change in catalytic activity. These results indicated that microcapsules have the potential to provide a favorable microenvironment for biodiesel production using solid base catalyst.
Concentrations of sodium (Na) and potassium (K), and osmolality (OSM) of 6 human serum albumin (HSA) injections obtained from each pharmaceutical manufacturer were determined. The concentrations of Na and K were determined by atomic absorption spectrometry, and OSM was analyzed with freezing point method.The reproducibilities of Na, K and OSM determinations were about 2, 4 and 2%, respectively.The determined data were compared with each value informed from 6 manufacturers.In Na concentrations of all HSA injections, there were no significant differences between the data and indicated ones on the packages (p<0.01).However, coefficient of variation (CV) value of 3 lots in one product was 13%.The concentrations of K determined in 4 products were different from those informed from each manufacturer;furthermore the CV values of 5 products were more than 19%.The CV values of OSM of 4 products were less than 5%, but those of 2 products were 13 and 16%, respectively.The ratios of OSM of 2 HSA injections to normal saline were less than indicated values on each package inserts.
