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The Knaften area is situated in the northern part of the Bothnian Basin in the central Svecofennian province of Sweden. Sedimentary rocks are here conformably intercalated with mafic to intermediat...

Spray drying is a widely used process to produce pharmaceutical powders. In traditional spray drying, the particle size distribution is wide and not well controlled. Using EHD atomization for spray drying offers a possibility to tailor the particle size and morphology. In conventional EHD spray drying, the generated particles are charged and need to be discharged to avoid Rayleigh breakup. Discharging adds complexity to the process and eliminates the possibility to collect the powder using an electric field. The present work describes a novel EHD spray drying setup based on a low-voltage nozzle. The low-voltage nozzle imparts moderate charge to the droplets, which makes discharging unnecessary. The charged particles can be controlled and collected by using an auxiliary electric field. The EHD spray dryer has been characterized in terms of particle size, particle morphology, process output, and yield. The size distribution of the generated particles is very narrow. Both porous and completely spherical particles can be produced. The yield of small-scale bench-top equipment was 20%, which is similar to the yield of a small-scale conventional spray dryer. The effective output with five nozzles was 75 mg/hr of dry powder. Because of the repelling forces associated with the unipolarly charged droplets, the number of nozzles can be increased without risking coalescence.

A recently recognized, more than 10 km wide deformation zone (the Ullared Deformation Zone, UDZ) can be followed for at least 30 km from the Mylonite Zone southeastwards into the Eastern Segment of the Sveconorwegian orogen of SW Sweden. The deformation affects a heterogeneous, high‐grade metamorphic gneiss complex, with locally preserved eclogite relics. The deformation is characterized by a strong, locally mylonitic, gneissosity, with a subhorizontal or moderately E‐ or ESE‐plunging stretching lineation. Deformational fabrics are related to metamorphic decompression and retrogression, and kinematic indicators show a top‐to‐the‐east and dextral sense of shear. Protolith ages (zircon) of pre‐ and post‐tectonic rocks bracket the age of deformation in the eastern part of the UDZ between c. 1380 and 955 Ma, but metamorphic mineral ages suggest an upper age limit of c. 1000 Ma. The deformation in the western part of the UDZ is contemporaneous with or younger than that in the eastern part. The deforma...

The granite massif in the Tjarnesjo area, southwestern Sweden, was deformed and metamorphosed under granulite facies conditions in late Sveconorwegian time. The intrusive is dominated by a coarse-grained, megacrystic orthoclase granite. Pb-Pb evaporation datings on single zircons from the granite yield an age of ca. 1.36 Ga, interpreted as the intrusion age. A similar age was obtained on zircons from quartz-monzonitic pyroxene bearing parts within the granite, here referred to as charnockitoids. Correlations with the ca. 1.38 Ga Torpa granite and its charnockitic associations in the Varberg region further to the west are supported by the intrusion-age of the Tjarnesjo granitoids, as well as the textural and chemical character of the two intrusives. Rocks within the Tjarnesjo massif vary from almost massive, to intensely deformed, sometimes even mylonitic rocks. Within large parts of the intrusive, the orthoclase megacrysts are recrystallized and transformed into mixed crystalline aggregates with components of intermediate microcline, where the proportion of microcline component is increased by the degree of deformation. However, in other deformed parts of the intrusive, the orthoclase is stable and the K-feldspar megacrysts may appear as fractured, surrounded by fine grained recrystallized domains of quartz, plagioclase and myrmekite. The different appearance of the K-feldspar megacrysts associated with deformation suggests an early event of deformation where orthoclase was stable, at high T-conditions, followed by a later deformational phase in which orthoclase was transformed into a mixed crystalline state with components of intermediate microcline. Furthermore, rocks with stable orthoclase appear homogeneously foliated whereas rocks that display a distinct structural change within the K-feldspar megaerysts mainly occur as discrete deformation zones. Zircons from an undeformed pegmatitic dyke, intersecting the gneissosity in a strongly deformed part of the granite, yield an age of ca. 955 Ma by Pb-Pb evaporation. This age is the minimum age of the regional deformation that affected the Tjarnesjo massif. The maximum age is set by the ca. 1.36 Ga intrusion age of the granite massif. The granulite facies mineral assemblages present in the charnockitoids define a high grade foliation at deformed sites. This high-grade event is interpreted to be late Sveconorwegian.