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The morphology of zinc electrodeposition was investigated from alkaline zincate solutions on single grains of known orientation in polycrystalline zinc electrodes under potentiostatic control. The effect of overpotential, solution composition, and substrate orientation were examined. The deposition morphology was observed with a scanning electron microscope. It was found possible to disrupt the deposition repeatedly for microscopic observation, and then continue deposition. At low overpotential (50 mV) epitaxial layer type growth was observed; the width of the macrosteps increased linearly with time. A theory explaining the linear step widening is proposed, which can also account for the observed effect of substrate orientation. At 100 mV, “boulders” were observed, not all of which were epitaxial with the substrate. They are suggested to be originated by nucleation. The boulder density per cm2 is first sharply increasing, then slowly decreasing with time. A statistical calculation for this is given, based on the model that large boulders consume the smaller ones. With further deposition a small fraction (ca. 0.1%) of the boulders develop into dendrites, their number being limited by the available total current. Experiments were carried out to differentiate between over‐potential and current control of morphology; overpotential was found to be the critical variable.

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The application of biopharmaceuticals for oral administration is a topic of great interest in the pharmaceutical industry due to the inherent advantages of oral delivery [1]. Biopharmaceutical formulations are more stable in the solid state than in liquid form; in addition, it has many advantages like storage at ambient temperature, longer shelf-life, easier product shipping and the possibility of controlled drug delivery [2]. Currently, the pharmaceutical industry is typically applying freeze drying and spray drying processes in order to obtain solid biopharmaceuticals, however, both technologies have disadvantages [3,4]. Freeze drying is a time-consuming batch technology, has high energy consumption, and the freezing can cause degradation of the biomolecules. On the contrary, spray drying can be operated continuously, is more economical, but can induce inactivation of heat-sensitive molecules, due to the high drying temperature. Electrospinning (ES), which is originally a fiber drawing technology, can be a promising alternative for continuous drying technologies, providing Abstract. Electrospinning is a promising drying technology providing a rapid and gentle drying at ambient temperature, thus electrospinning of polyvinyl alcohol aqueous solutions was investigated for the solid formulation of biopharmaceuticals. The commonly used single-needle electrospinning does not have adequate productivity to satisfy the industrial requirements, therefore our aim was to study the scale-up of the technology by using high-speed electrospinning. High molecular weight polyethylene oxide as a secondary polymer was applied to enhance the fiber formation of polyvinyl alcohol. While polyvinyl alcohol-polyethylene oxide formulations resulted in adequate fiber formation it was not possible to process them further as the friability of the fibers was too low. In order to increase the friability, the effect of adding various sugars (mannitol, glucose, lactose, saccharose, and trehalose) was investigated. The results showed that mannitol was the best friability enhancing excipient because of its crystallinity and low moisture content in the fibrous sample. In contrast, glucose, lactose, saccharose, and trehalose were amorphous with higher moisture content and fibers containing these were grindable only after post-drying.

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Microholographic data storage system model is presented that includes non-linear and non-local behavior of the storage material for accurate simulation of the system and optimization of the writing process. For the description of the photopolymer material a diffusion based nonlocal material model is used. The diffusion equation is solved numerically and the modulation of the dielectric constant is calculated. Diffraction efficiency of simulated microholograms and measurements were compared, and they show good agreement.

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