Electric-field induced droplet vertical vibration and horizontal motion: Experiments and simulations

In this work, Electrowetting on Dielectric (EWOD) and electrostatic induction (ESI) are employed to manipulate droplet on the PDMS-ITO substrate. Firstly, we report large vertical vibrations of the droplet, induced by EWOD, within a voltage range of 40 to 260 V. The droplet's transition from a vibrating state to a static equilibrium state are investigated in detail. It is indicated that the contact angle changes synchronously with voltage during the vibration. The electric signal in the circuit is measured to analyze the vibration state that varies with time. By studying the influence of driving voltage on the contact angle and the amplitude in the vibration, it is shown that the saturation voltage of both contact angle and amplitude is about 120 V. The intrinsic connection between contact angle saturation and amplitude saturation is clarified by studying the surface energy of the droplet. A theoretical model is constructed to numerically simulate the vibration morphology and amplitude of the droplet. Secondly, we realize the horizontal motion of droplets by ESI at the voltage less than 1000 V. The charge and electric force on the droplet are numerically calculated. The frictional resistance coefficients of the droplet are determined by the deceleration of the droplet. Under consideration of frictional resistance of the substrate and viscous resistance of the liquid, the motion of the droplet is calculated at 400 V and 1000 V, respectively. This work introduces a new method for manipulating various forms of droplet motion using the single apparatus

An integrated overview of spatiotemporal organization and regulation in mitosis in terms of the proteins in the functional supercomplexes

Eukaryotic cells may divide via the critical cellular process of cell division/mitosis, resulting in two daughter cells with the same genetic information. A large number of dedicated proteins are involved in this process and spatiotemporally assembled into three distinct super-complex structures/organelles, including the centrosome/spindle pole body, kinetochore/centromere and cleavage furrow/midbody/bud neck, so as to precisely modulate the cell division/mitosis events of chromosome alignment, chromosome segregation and cytokinesis in an orderly fashion. In recent years, many efforts have been made to identify the protein components and architecture of these subcellular organelles, aiming to uncover the organelle assembly pathways, determine the molecular mechanisms underlying the organelle functions, and thereby provide new therapeutic strategies for a variety of diseases. However, the organelles are highly dynamic structures, making it difficult to identify the entire components. Here, we review the current knowledge of the identified protein components governing the organization and functioning of organelles, especially in human and yeast cells, and discuss the multi-localized protein components mediating the communication between organelles during cell division

Pressure-Induced Reverse Reaction of the Photochemical Decomposition of Germanium Tetraiodide Molecular Crystal

GeI₄ molecular crystal and its solution in cyclohexane were irradiated by lasers of different wavelengths to investigate the critical wavelength for photochemical decomposition of GeI₄. We have observed that 633 nm laser can photochemically decompose GeI₄, exceeding the previously reported wavelength limit of 514 nm. XPS spectra indicate that GeI₄ is photochemically decomposed into Ge₂I₆ and I₂; unlike GeBr₄, Ge²⁺ (GeI₂) cannot be found in the photochemical reaction products. Raman spectra measurement of GeI₄ under high pressure up to 24 GPa show that Raman signals of Ge₂I₆ and I₂ vanish at 0.5 to 1.7 GPa. This finding clearly shows that high pressure can effectively reverse the photochemical decomposition of GeI₄ and influence the direction of the solid-state reaction, which is usually found on gas-phase reactions

Cyclic Phase Transition from Hexagonal to Orthorhombic Then Back to Hexagonal of EuF₃ While Loading Uniaxial Pressure and under High Temperature

The structure and photoluminescence properties are investigated under high pressure and high temperature for pure orthorhombic and hexagonal EuF₃ nanocrystals. Under hydrostatic compression, the hexagonal EuF₃ remains stable at pressures up to 26 GPa. Under nonhydrostatic compression, a cyclic phase transition from hexagonal to orthorhombic and then back to hexagonal is observed for the first time. When loading uniaxial compression, the pure hexagonal EuF₃ partly transforms to orthorhombic at 70 MPa, then the orthorhombic EuF₃ transforms to hexagonal at about 3 GPa, and the transition is completed at about 10 GPa. The cyclic phase transition is also observed during the heating process; the hexagonal transforms to orthorhombic at 550 °C and then to hexagonal at 855 °C. The content phase diagrams are obtained under high pressure and at high temperature

Pressure-Induced Conformer Modifications and Electronic Structural Changes in 1,3,5-Triamino-2,4,6-trinitrobenzene (TATB) up to 20 GPa

To probe the behavior of structural evolution and optical properties in solid energetic material TATB, X-ray diffraction (XRD) and Raman and absorption spectroscopy were performed under high pressure up to 20 GPa. The absorption edge shifts to red, and the color significantly varies with increasing pressure for TATB. The XRD patterns under high pressure indicate that TATB maintains the triclinic structure within this pressure range. An electronic structural change is observed at ∼5 GPa, resulting from the modification of conformers of TATB, which is associated with the rotation of nitro and amino groups under high pressure. The current experimental results clarified the absence of phase transition below 20 GPa and confirmed that the pressure-induced color change originates from the enhancing conjugation of π orbital due to the shorting C–NO₂ bonds and the rotation of nitro groups with increasing pressure. The third-order Birch–Murnaghan equation of state is obtained up to 16.5 GPa, which is helpful for calculating researchers to verify the correctness of their models