• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.423-426
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• 2006

Paper has fibers and fines network structure and it is strongly affected by interface bonding between fibers. Depending on the inter-fiber bonding, paper bulk is determined. Fines play an important roll in Campbell and consolidation effect through wet pressing and drying operations. Refined Sw-BKP, Hw-BKP and BCTMP fines were used to investigate the fines effect. Wet-web strength, breaking length, scattering coefficient, and hydrodynamic specific volume were measured. According to the result of experiments, chemical and morphological compositions of fines do not strongly affect to wet-web forming, but strongly affect to drying operations which form hydrogen bonding among fiber-fines-fiber matrixes. Paper bulk should be controlled by the extent of hydrogen bonding between fibers during drying operations.

• Journal of the Korean Magnetic Resonance Society
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• v.12 no.1
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• pp.51-59
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• 2008

Convection effect in liquids has been one of the main targets to be overcome in pulsed-field-gradient NMR measurements of self-diffusion coefficients since the temperature gradient along the sample tube generated by the heating and/or cooling process causes the effect, resulting in additional diffusion. It is known that the capillary is the most appropriate tube type for diffusion experiments at variable temperatures since the narrower tube suppresses convection effectively. For evaluating the properties of hydrogen bonding, diffusion coefficients of the $K^+$-complexed and free valinomycin in a micro tube have been determined at various temperatures. From the analysis of the obtained diffusion coefficient values, we could conclude that the intramolecular hydrogen bonding in both of the $K^+$ complexed and free valinomycin in a non-polar solvent is preserved over the observed temperature range, and the temperature dependence of hydrogen bonding is more pronounced in free valinomycin. It is also thought that there is no big change in the radius of the $K^+$-complexed as temperature is varied, and the ratio of overall radius, $r_{complex}/r_{free}$ is slightly decreased as temperature rises.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.52-55
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• 1961

Assuming an intramolecular hydrogen-bonding, computation has been made on the optical rotatory power of 2-Chloro-1-Propanol. The magnitude of the calculated rotation is in fair agreement with the measured value of Lucas (calculated value: 21.6. measured value: 17.39). The agreement supports the validity of the assumption concerning the hydrogen-bonding between O atom and Cl atom. The agreement in sign confirms the validity the Fischer projection formula given by Lucas.

• Bulletin of the Korean Chemical Society
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• v.2 no.1
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• pp.8-11
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• 1981

A new potential function based on spectroscopic results for diatomic molecules is presented and applied to the hydrogen bonding systems. The potential energy of interaction is supposed to have electrostatic, polarization, dispersion, repulsion and effective charge-transfer contributions. Estimates of the effective charge-transfer quantity have been made based on the average charge of the proton donor and the acceptor atoms. For dimers such as water, methanol, acetic acid and formic acid, the vibrational stretching frequencies and dimerization energies are calculated and dicussed in connection with Badger-Bauer rule.

• Journal of the Mineralogical Society of Korea
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• v.16 no.1
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• pp.65-73
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• 2003

In this study we have derived the two correction methods of hydrogen bonding distance. In case of the intermediate or long hydrogen bond(＞2.5 $\AA$), hydrogen bonding distances can be corrected by using the function d(O-H)=exp((2.173-d(O…O))/0.138)+0.958 obtained by least- squares fit to the data from the neutron diffraction at low temperatures. The valence-least-squares method is effective for the distance correction of very short hydrogen bond(<2.5 $\AA$). The distance correction is necessary for the long intermolecular hydrogen bond obtained from X-ray diffraction analysis.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.644-647
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• 2000

The properties of hydrogen bonding between poly(2-ethyl-2-oxazoline)[PEOx] and poly(acrylic acid)[PAA] were investigated. PEOx and PAA formed stable complex and precipitated due to hydrogen bonding between hydrogen of PAA and oxygen of PEOx in acidic condition(below pH 4.3). Optimum reaction ratio of PEOx and PAA was determined as mass ratio of 1:1.5 for applications in aqueous two phase system. The mixtures of the polymers formed aqueous two phase system with dextran solution after the breakage of hydrogen bondings. This properties can be used for the recovery of valuable products.

• Transactions on Electrical and Electronic Materials
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• v.1 no.1
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• pp.6-11
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• 2000

The hydrogen plasma treatment of silicon wafers in the reactive ion-etching mode was studied for the application to silicon-on-insulator wafers which were prepared using the wafer bonding technique. The chemical reactions of hydrogen plasma with surface were used for both surface activation and removal of surface contaminants. As a result of exposure of silicon wafers to the plasma, an active oxide layer was found on the surface. This layer was rendered hydrophilic. The surface roughness and morphology were examined as functions of the plasma exposing time and power. In addition, the surface became smoother with the shorter plasma exposing time and power. The value of initial surface energy estimated by the crack propagation method was 506 mJ/㎡, which was up to about three times higher as compared to the case of conventional direct using the wet RCA cleaning method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.426-427
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• 2007

Here we describe the formation of a self-assembled film of thin multiwalled carbon Nanotubes(t-MWNT) modified with hydroxy groups through hydrogen peroxide treatment. Morphologies of t-MWNT films could be controlled by the various coating method, such as filtering, drop casting, spraying method, etc. The results show that on densification of the CNT suspension during drying, multiple hydroxy group-modified MWNTs can be self-assembled through strong surface hydrogen bond interaction while MWNTs usually exist an entangled state in the film. The interaction between t-MWNT was illustrated from Raman spectrum of spray coated films.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.312-315
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• 2018

Although the reversibility of 10,12-pentacosadiynoic amino meta-acid(PCDA-mBzA) against temperature and pH was reported, the modulation of reversibility by ion adsorption at terminal functional group has not been investigated. In this work, we developed a simple method for modulating the reversibility of PCDA-mBzA films upon a thermal stimulus by cadmium ion adsorption inducing the breakage of the outer hydrogen bonding of two hydrogen bonds, which are responsible for the reversible properties of PCDA-mBzA. External reflection-Fourier transform infrared (ER-FTIR) analyses revealed that the hydrogen bonding between the carboxylic acid groups was broken through ion adsorption and only a single hydrogen bond between the amide groups remained in the PCDA-mBzA polymer. In addition, PCDA-mBzA films could recover their original property through cadmium ion desorption. These results present that the transition between reversibility and irreversibility can be modulated artificially simply through the adsorption and desorption of metal ions.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.72.2-72.2
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• 2009