Biomedical subjects

MS Kim

Publications and source records attributed to MS Kim.

At least 19 recordsLinked to original sources

PubMed2001

A Study on the Adsorption Characteristics of Orthophosphates on Rutile-Type Titanium Dioxide in Aqueous Solutions.

Rutile-type titanium dioxide is widely used as a pigment for paint, coating ink, paper, plastic products, and cards because of its very whiteness and outstanding hiding property. It has two weak properties to be improved, however, one being its coagulation in compounding and the other its decreasing whiteness owing to poor heat resistance. To solve these problems, a study on the treatment of titanium dioxide surfaces by adsorption technology has been performed. Experiments have been carried out to establish the adsorption isotherms of orthophosphates on titanium dioxide and to investigate the effect of organic solvents on adsorption. It is shown that the adsorption isotherms vary with pH. A Freundlich adsorption isotherm is suitable for the acidic and basic regions, while a Langmuir adsorption isotherm is suitable for the region of pH 5-8 where a maximum adsorption has been achieved. In aqueous solutions containing organic solvents, the adsorption was strongest with aqueous solutions containing 1 wt% toluene and weakest with those containing 1 wt% ethanol. Among the alcohols used, the adsorption was strongest with the aqueous solution containing 1 wt% butanol and weakest with that containing 1 wt% ethanol, thus showing a correlation with the molecular weight of the alcohol. Copyright 2001 Academic Press.

Journal Article↗

PubMed2000

Entanglement teleportation via werner states

Transfer of entanglement and information is studied for quantum teleportation of an unknown entangled state through noisy quantum channels. We find that the quantum entanglement of the unknown state can be lost during the teleportation even when the channel is quantum correlated. We introduce a fundamental parameter of correlation information which dissipates linearly during the teleportation through the noisy channel. Analyzing the transfer of correlation information, we show that the purity of the initial state is important in determining the entanglement of the replica state.

Journal Article↗

PubMed2000

Dissociation dynamics of propargyl chloride molecular ion near the reaction threshold: manifestation of quantum mechanical tunneling

The Cl loss from the propargyl chloride molecular ion has been investigated using mass-analyzed ion kinetic energy spectrometry (MIKES). The kinetic energy release distribution in the unimolecular dissociation has been determined. The potential energy surface for the mechanistic pathway has been calculated at the B3LYP/6-311G** density functional theory level. The calculated potential energy surface suggested that the threshold dissociation of the propargyl chloride molecular ion produces the C(3)H(3)(+) ion, only with the cyclopropenium structure, and with the release of a large amount of kinetic energy. This is in agreement with experimental results. Also, calculation of the rate constants with statistical rate models predicted that the reaction observed on a microsecond time scale occurs via tunneling through the rate-determining isomerization barrier for H-atom transfer. It has been found that a broad lifetime distribution is a manifestation of quantum mechanical tunneling of a precursor prepared under thermal conditions. Reinterpretation of previous photoelectron-photoion coincidence results taking into account the tunneling effect necessitated raising the critical energy to 0.64 eV from the energy of 0.34 eV reported previously. Copyright 2000 John Wiley & Sons, Ltd.

Journal Article↗

PubMed1999

Internal energy content of n-butylbenzene, bromobenzene, iodobenzene and aniline molecular ions generated by two-photon ionization at 266 nm. A photodissociation study

A technique to investigate photodissociation kinetics on a nanosecond time scale has been devised for molecular ions generated by multiphoton ionization (MPI) using mass-analyzed ion kinetic energy spectrometry. The branching ratio or rate constant has been determined for the photodissociation of the n-butylbenzene, bromobenzene, iodobenzene, and aniline molecular ions generated by MPI at 266 nm. The ion internal energies have been estimated by comparing the measured kinetic data with the previous energy dependence data. The analysis has shown that only those molecular ions generated by two-photon ionization contribute to the photodissociation signals. Around half of the available energy has been found to remain as molecular ion internal energy in the two-photon ionization process. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗

PubMed1997

Blend of Electroactive Complexes of Polyaniline and Surfactant with Alkylated Polyacrylate

The cocrystallization of alkylated polyimides and polyesters, as shown by Ballauff et al., offers an opportunity to mix alkylated electrically conducting blends with the alkylated insulating materials. In this investigation we have used a flexible alkylated polymer to blend with a stiff alkylated conducting polymer. Comb-shaped poly(octadecyl acrylate) (PODA) was blended with polyaniline emeraldine base (PANI)/dodecyl benzenesulfonic acid (DBSA) complex to investigate the effect of long alkyl chain of flexible polymer on the electroactive rigid rod-like PANI(DBSA)4 (weight ratio) complex. Binary blend DBSA/PODA was also used as a model to investigate the intermolecular interaction between unprotonated excess amounts of DBSA and PODA in the ternary blend. Cross-polarized optical microscope (OM) and wide-angle X-ray diffraction (WAXD) were applied to observe the highly ordered mesophase structure of these blends. This newly formed mesomorphic structure of DBSA/PODA binary blend due to the hydrogen bonding was observed when the PODA content was below 40 wt% in binary blend and these blend samples show a homogeneous one phase above 68°C by OM. With addition of 10 wt% of PODA in ternary blend, the homogeneous smectic liquid crystalline structure was clearly confirmed by OM and WAXD. The intermolecular interactions that occurred in the blend systems was explained for each different characteristic peak with FT-IR spectra.

Journal Article↗

PubMed1996