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We have developed an experimental apparatus named KOTOBUKI-1 for use in the coherent x-ray diffraction imaging experiments of frozen-hydrated non-crystalline particles at cryogenic temperature. The apparatus allows us to collect diffraction data for frozen-hydrated specimens at 66 K and provides an experimental environment to easily transfer frozen-hydrated specimens from liquid nitrogen storage to the specimen stage for x-ray exposure. Since 2012, the apparatus has been used in the single-shot diffraction data collection of non-crystalline biological cells and cellular components with dimensions from micrometer to submicrometer using x-ray free electron lasers at SACLA. Here we report on the performance of the KOTOBUKI-1 diffraction apparatus and some structure analyses of biological cells and cellular components. Based on the present results, we also discuss the future developments of diffraction apparatus for more efficient data collection.

Contributions of spontaneous polarization (P s) to capacitance (C) in ferroelectric liquid crystal (FLC) cells are analyzed in the present paper. Reorientation properties of FLC molecules have been studied on the basis of capacitance vs applied voltage characteristics. In the course of polarization reversal, C increases as the component of P s parallel to the substrate of the cell becomes large.

A method for molecular alignment of a ferroelectric smectic liquid crystal is reported. Homeotropic alignment with a small angle of pretilt was obtained by surface treatment with oblique deposition of metal oxide, such as yttria and alumina. Furthermore, an electric field was applied during the cooling period from isotropic liquid to chiral smectic phase. Uniformly pretilted alignment could be obtained by using the oblique deposition and DC field application. On the other hand, a twisted alignment was obtained on the obliquely deposited metal oxide film when an AC electric field was applied instead of a DC field. Electrooptical characteristics of these cells are shown.