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Volcan Sollipulli is a Quaternary stratovolcano situated at 38'50'S in the Southern Volcanic Zone of the Andes of Chile, about 25 km east of the volcanic front. The volcano is capped by a large (25 km2 approx. ) ice-filled caldera. Sollipulli is unusual in this region of predominantly basic to intermediate magmatism in that it has erupted a wide range of magmas from high-MgO (9%) basalt to rhyolite (74% Si02). The last major eruption, the Alpehue eruption, occurred at about 2,900 B. P, ejecting about 4.7 km3 (D. R. E) of homogeneous high-Si dacite pumice, forming an extensive plinian airfall deposit and ignimbrite. The caldera predates the Alpehue eruption and is believed to have formed by passive subsidence combined with erosion rather than by catastrophic collapse. Withdrawal of magma from beneath the centre of the structure and effusive eruption induced subsidence. Magma mixing, fractional crystallisation and crustal assimilation are important evolutionary mechanisms. Some mixed dacite lavas contain primitive basaltic magmatic inclusions with diktytaxitic textures indicative of rapid quenching. Strongly resorbed, reverse zoned sodic plagioclase of dacitic origin occurs in basic inclusions and high-Mg olivine occurs in dacites. Other sequences appeart o have evolved predominantly by fractional crystallisation with some crustal assimilation. The amount of crustal assimilation increasesw ith decreasinga gei n somec ases. Older Sollipulli basic magmash ave evolved as small batchesp redominantlya t moderatet o high pressurein the mid-lower crust whereas younger basic magmas have experienced protracted upper crustal histories in a large magma chamber, fractionating and assimilating crust to produce abundant high-Si dacite. Sollipulli magmas have an anhydrous mineralogy except for the occurrence of very minor amphibolei n somem ixed rocks. Magma temperaturesra ngef rom about 118 0'C in basalts to about 900'C in dacites. The most primitive samples represent hot and relatively water-poor (<1-2% H20) high-Al basaltic magmas. Crystal-rich andesitesa nd dacites record lower temperaturesth an crystal-poore quivalents. The cooler porphyritic magmas appear to have assimilated more crust than the hotter crystal-poor magmas. Most magmas have evolved at oxygen fugacities close to the NNO buffer curve. Large volcanic front centres in the region erupt magmas with lower incompatible elementa bundancea nd higher Ba/Nb than magmase rupteda t minor monogeneticc entresa, nd at stratovolcanoesto the easto f the front, which have incompatiblee lements ignatures transitional towards back-arc alkaline magmas (e. g. high Nb, Ce/Y). Older Sollipulli magmas also have high Ce/Y and Nb similar to magmas at some monogenetic centres but have lower Ti and Y. Younger Sollipulli magmas have even lower Ti and Y. Sollipulli basic magmasa re also characterisedb y higher Mg/Ni than all regional magmas. The simplest explanation is that the high Nb, Ce/Y magmas have assimilated enriched mantle lithosphere. The Ti, Y, Mg/Ni systematics suggest that the Sollipulli magmasa re generated by higher degrees of melting of a similar MORB-source-type mantle than the regional magmas. In the case of the younger Sollipulli magmas, generation from mantle which was slightly depleted during the earlier phase is also possible but the older magmas show no evidence in their spinel compositions for derivation from refractory mantle.

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The major constituents of the plankton, phytoplankton, cladocera, copepods and chaetognaths, sampled in the 1951 oceanographic survey of the British Columbia Inlets are reported in concentrations per cubic meter of water. Horizontal plankton tows sampled four depths, 5, 21, 32 and 47 feet, respectively. The distribution of each group is discussed in relation to the hydrographic data and the present theory of inlet circulation. The inlets investigated fall into two general groups, (a) those which are long and have a large freshwater discharge at the head and (b) those which have a small freshwater discharge and are short. The data from six inlets making up the former have been grouped together and are discussed as the Average Inlet. Those inlets making up the latter group are classified under the general heading of atypical inlets; each is discussed separately. In the Average Inlet the plankton volumes were the greatest at the mouth, particularly towards the surface. The concentration of plankton is shown to be a result of local phytoplankton production. In the absence of currents the phytoplankton are shown to be limited vertically by density. The zooplankton are divided into three groups on the basis of their response to the physical factors. The distribution of cladocera indicates that it is positively phototropic while that of the copepods and chaetognaths indicate that that they are negatively phototropic. The chaetognaths are found to be absent from all the atypical inlets, the cladocera from three. The copepods are concentrated at the depth which is associated with the compensation light intensity. Attention is drawn to the fact that this report is a qualitative description of the relationship between the distribution of the plankton and the physical oceanographic conditions. Future surveys will have to sample more extensively and intensively. / Science, Faculty of / Zoology, Department of / Graduate

The need of the experimental support for validation of the computational tools to be applied to analyze the mixing of diluted slugs has been recognized in various countries. The test series for the International Standard Problem ISP-43 provides a platform for experiences to be applied to the simulation of a well-defined test series. Test A and B of the UM2x4 loop test facility were calculated with the CFD Code CFX-4.3. Sensitivity studies were made to analyze the used turbulence model and numerical errors. The results show good agreement with the experimental data for both tests.

The thin interface separating the inner turbulent region from the outer irrotational fluid is analyzed in a direct numerical simulation of a spatially developing turbulent mixing layer. A vorticity threshold is defined to detect the interface separating the turbulent from the non-turbulent regions of the flow, and to calculate statistics conditioned on the distance from this interface. Velocity and passive scalar statistics are computed and compared to the results of studies addressing other shear flows, such as turbulent jets and wakes. The conditional statistics for velocity are in remarkable agreement with the results for other types of free shear flow available in the literature. In addition, a detailed analysis of the passive scalar field (with Sc 1) in the vicinity of the interface is presented. The scalar has a jump at the interface, even stronger than that observed for velocity. The strong jump for the scalar has been observed before in the case of high Schmidt number, but it is a new result for Schmidt number of order one. Finally, the dissipation for the kinetic energy and the scalar are presented. While the kinetic energy dissipation has its maximum far from the interface, the scalar dissipation is characterized by a strong peak very close to the interface.

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Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical Technology Supervisor: Assoc. Prof. PharmDr. Zdenka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Andrea Suther Bunes Title of Thesis: Study of influence of hydrophilic carriers on the dissolution rate of a BCS II drug The aim of this thesis was to study the effect of mixing and co-milling with hydrophilic carriers on the dissolution rate of a model BCS II drug meloxicam. The mixtures of two different drug loads (1-1, 1-8) were characterized for granulometric and dissolution parameters. USP-4 apparatus assembled with a flow-through powder cell (an open loop) was used to estimate meloxicam relative dissolution rate rrel (min-1 ). Mixing with lactose, particularly in a higher ratio, increased the relative dissolution rate in comparison to the pure meloxicam. The effect was further increased by co-milling, but an unfavourable event of agglomeration occurred, especially for the 1-1 drug-excipient ratio sample. Adding chitosan solved this problem due to the formation of interactive mixture. The co-milled sample containing chitosan and lactose in a 1-8 ratio showed the highest rrel = 0.48 min-1 .