The structures of biomacromolecules are conventionally characterized by crystallography and cryogenic electron microscopy . The requirements of sample preparation limit the understanding of the specimens in their native states. Small-angle x-ray scattering (SAXS) has the capability of obtaining structural information from biological specimens in solution. However, resolving the structure from the acquired one-dimensional (1D) diffraction data requires the prior knowledge of the sample, and no unique solution can be guaranteed. Coherent diffraction imaging (CDI) provides excellent uniqueness in 2D/3D phase retrieval while the resolution is restricted by the poor signal-to-noise ratio at high-angle scattering. Here we combine CDI and SAXS to directly image a 19-nm-sized nodavirus particle in solution and determine the core-shell density distribution at a 1.3 nm pixel resolution. With 77,170 diffraction patterns summarized from randomly distributed nodavirus particles, the structural information can be obtained from the diffraction intensity alone without preknowledge. The hollow density distribution of a nodavirus particle revealed by our reconstruction is consistent with the structural determinations from crystallography and cryogenic electron microscopy. We believe this work represents a new protocol for characterizing the structures of macromolecules in solution from accumulated x-ray scattering data.

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A multifunctional emotion-teaching aid was developed in this research to teach “Know the types of emotions”, “Understand the causes of emotions”, “Guide to express negative emotions”, and “Inspire positive emotions of gratitude”. The aid helped young children learn, understand, and express their emotions actively. The teaching aid enabled children to express negative emotions and trigger positive emotions of gratitude. Through teaching aids, children learned the six emotions of “happy, angry, sad, grateful, sorry, and afraid”. After the development of teaching aids was completed, the advantages and disadvantages of emotional education toys on the market were compared with those of the developed teaching aids. Quantitative and qualitative research was carried out to understand the effectiveness of the product. In terms of quantitative research, a questionnaire was created to test its reliability and validity. Another 100 education and security personnel were invited as research objects for the survey of satisfaction after the practical application of traditional emotion teaching toys and the developed teaching aids. The effectiveness of new teaching aids was validated with the result. The application of the research results and suggestions were presented for future related research.

Coherent diffraction microscopy (CDM) is a potential approach to image micromaterials at atomic resolution without crystals. Due to the lack of high-angle scattering, the achieved resolution is limited to several nanometers. Small-angle scattering allows researchers to reveal high-resolution 3D structures of specimens by fitting 1D diffraction signals. However, prerequisite 3D models and non-unique solutions restrict the potential to image general specimens. Under the assumption of an ensemble containing large amounts of identical specimens with the same orientation, the intensity distribution of the diffraction pattern of the whole ensemble is approximated to the form factor of a single specimen multiplied by the number of identical specimens. Since the diffraction intensities are contributed from the whole ensemble, the signal can be significantly extended to high-frequency regions. The feasibility of ensemble diffraction microscopy (EDM) was demonstrated by a designed sample using both totally and partially coherent X-ray sources at Taiwan Photon Source (TPS). The reconstructed images show excellent consistency with the image of a scanning electron microscope. This work represents a new protocol for directly characterizing the structures of nanomaterials, or potentially biomacromolecules, from accumulated X-ray scattering data.