Side-View Operando Optical Microscopy Analysis of a Graphite Anode to Study Its Kinetic Hysteresis

Operando analyses have provided several breakthroughs in the construction of high-performance materials and devices, including energy storage systems. However, despite the advances in electrode engineering, the formidable issues of lithium intercalation and deintercalation kinetics cannot be investigated by using planar observations. This study concerns side-view operando observation by optical microscopy of a graphite anode based on its color changes during electrochemical lithiation. Since the graphite color varies according to the optical energy gap during lithiation and delithiation, this technique can be used to study the corresponding charge-discharge kinetics. In addition, the cell configuration uses liquid electrolytes similar to commercial cells, allowing practical application. Furthermore, this side-view observation has shown that microscale spatial variations in rate and composition control the insertion and deinsertion, revealing the kinetics throughout the whole electrode. The results of this study could enhance the fundamental understanding of the kinetics of battery materials

Concomitant Laparoendoscopic Single-Site Surgery for Ureterolithotomy and Contralateral Renal Cyst Marsupialization

A 63-year-old woman presented with acute right-flank pain and left-flank pain. Computed tomography identified a right ureter stone and a left renal cyst. The patient underwent concomitant laparoendoscopic single-site surgery (LESS) for ureterolithotomy and renal cyst marsupialization with the use of an Alexis® wound retractor, which was inserted through the umbilical incision. Flexible laparoscopic instruments and conventional rigid instruments were used during LESS following a procedure similar to that used with conventional laparoscopic surgery without additional transcutaneous ports. LESS may be more efficient at treating bilateral diseases than is conventional laparoscopic surgery

Quasi-Eigenstate Evolution in Open Chaotic Billiards

We experimentally studied evolution of quasi-eigenmodes as classical dynamics undergoing a transition from being regular to chaotic in open quantum billiards. In a deformation-variable microcavity we traced all high-Q cavity modes in a wide range of frequency as the cavity deformation increased. By employing an internal parameter we were able to obtain a mode-dynamics diagram at a given deformation, showing avoided crossings between different mode groups, and could directly observe the coupling strengths induced by ray chaos among encountering modes. We also show that the observed mode-dynamics diagrams reflect the underlying classical ray dynamics in the phase space.Comment: 4 pages, 4 figure

Development of deformation-tunable quadrupolar microcavity

We have developed a technique for realizing a two-dimensional quadrupolar microcavity with its deformation variable from 0% to 20% continuously. We employed a microjet ejected from a noncircular orifice in order to generate a stationary column with modulated quadrupolar deformation in its cross section. Wavelength red shifts of low-order cavity modes due to shape deformation were measured and were found to be in good agreement with the wave calculation for the same deformation, indicating the observed deformation is quadrupolar in nature.Comment: 7 pages, 6 figures, intended for Rev. Sci. Instu

Chaos-assisted nonresonant optical pumping of quadrupole-deformed microlasers

Efficient nonresonant optical pumping of a high-Q scar mode in a two-dimensional quadrupole-deformed microlaser has been demonstrated based on ray and wave chaos. Three-fold enhancement in the lasing power was achieved at a properly chosen pumping angle. The experimental result is consistent with ray tracing and wave overlap integral calculations.Comment: 3 pages, 5 figure