김동욱 교수

The nature of the anion−π interaction has been investigated by carrying out high level ab initio calculations of the complexes of halide (F-, Cl-, and Br-), linear organic (CN-, NC-), and trigonal planar organic (NO3- and CO32-) anions with different kinds of π systems, viz. olefinic (tetrafluoroethene), aromatic (hexafluorobenzene), and heteroaromatic (1,3,5-triazine). In an effort to comprehend the underlying basis of this interaction, we have also carried out a rigorous decomposition of the i

The nature of the cation−π interaction has been examined by carrying out high level ab initio calculations of both metallic (Li+,Na+,K+, and Ag+) and organic (NH4+, C(NH2)3+, and N(CH3)4+) cations with different classes of π systems, viz. alkenes (ethene), arenes (benzene), and heteroarenes (pyrrole). The calculations, which include a rigorous decomposition of the interaction energies, indicate that the interaction of these π systems with the metal cations is characterized by contributions from

We demonstrate a compactly integrated polarization beam splitter (PBS) with high polarization extinction ratios greater than 20 dB over the full C-band wavelength range based on a simple bridged silicon nanowaveguide directional coupler. The PBS device is designed via three dimensional finite-difference time-domain (3D-FDTD) simulation, and fabricated experimentally. The optimum dimension of the bridge waveguide is determined to be 7.5-μm-long and 500 nm-wide for 250-nm thick silicon core. At th

Among patients who died of cancer, significant proportions were found to have received chemotherapy up to the end-of-life and to have visited ERs. Hospice referrals and discussions about DNR were not conducted well during the end-of-life period in Korea.

The SAM layer which formed hydrogen-bonding to the methylammonium of the perovskite induced dipole moments at the interface, resulting in energy band bending and increased built-in voltage, and consequently, improved charge transfer of the PSC.

From July 1990 through June 1994, 106 knees (102 patients) were treated for discoid meniscus. Fifteen knees (15 patients) were associated with other intraarticular anatomic variants. There were eight knees (8 patients) with anomalous insertion of the anterior horn of the medial meniscus into the anterior cruciate ligament, and seven knees (7 patients) with anterior expansion of the anterior portion of the anterior cruciate ligament below the anterior tibial margin. Among the latter, one patient

The synthesis of highly crystalline perovskite BaSnO3 nanoparticles for use as photoanode materials in dye-sensitized solar cells (DSSCs) is reported, and the photovoltaic properties of DSSCs based on BaSnO3 nanoparticles (BaSnO3 cells) are demonstrated. The resulting DSSCs exhibit remarkably rapid charge collection and a DSSC fabricated with a BaSnO3 film thickness of 43 µm leads to a high energy conversion efficiency of 5.2 %, which is one of the highest reported for ternary oxide-based DSSCs.