• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.265-266
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• 2002

Nano materials have great potential for development of advanced lubricating and protecting materials. Nano-particles capped by organic compound such as organic acid, dialkyldithiophosphate (DDP) are capable to disperse stably in lubricating oils, and are able to reduce wear and to increase load-carrying capacity.

• Journal of the Korean institute of surface engineering
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• v.11 no.3
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• pp.3-9
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• 1978

Organic compounds, such as aldehydes, amines, amides, sulfur compounds of polymers, have been added to cyanide Zinc electroplating bath to achieve in improvement of the brightness and of the current efficiency. It was found that the addition of only one compound o these organic compounds in the bath were unsuitable to be used for brightener, but mixure of aldehyde and reaction products obtained from epoxides and amines and/or amides were suitable for brightener in cyanide zinc electroprating baths.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.57-61
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• 1969

From the principle of CHN-Corder analysis, it is obvious that seperation of chlorine and bromine in a sample is nearly impossible. In order to analyze, chlorine, bromine, and sulfur seperately in a sample which is a single organic compound or a mixture of organic drugs, combination of flask combustion method and CHN-Corder was successfully attempted.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.793-797
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• 2014

To develop a methodology for absolute determination of the surface areal density of functional groups on organic and bio thin films, medium energy ion scattering (MEIS) spectroscopy was utilized to provide references for calibration of X-ray photoelectron spectroscopy (XPS) or Fourier transformation-infrared (FT-IR) intensities. By using the MEIS, XPS, and FT-IR techniques, we were able to analyze the organic thin film of a Ru dye compound ($C_{58}H_{86}O_8N_8S_2Ru$), which consists of one Ru atom and various stoichiometric functional groups. From the MEIS analysis, the absolute surface areal density of Ru atoms (or Ru dye molecules) was determined. The surface areal densities of stoichiometric functional groups in the Ru dye compound were used as references for the calibration of XPS and FT-IR intensities for each functional group. The complementary use of MEIS, XPS, and FT-IR to determine the absolute surface areal density of functional groups on organic and bio thin films will be useful for more reliable development of applications based on organic thin films in areas such as flexible displays, solar cells, organic sensors, biomaterials, and biochips.

• Textile Coloration and Finishing
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• v.33 no.3
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• pp.153-160
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• 2021

In this study, composite materials were prepared by varying the content of glass fiber and bamboo fiber in PP/glass fiber/bamboo fiber. Experiments were conducted to confirm the mechanical properties(tensile, impact and burst strength) and volatile organic compound content of the bamboo fiber composite prepared under these conditions. An improvement in the main properties was observed at a fiber content of 30wt%. When the fiber fraction was increased above 30wt%, the mechanical properties tended to decrease due to the agglomeration of fibers at higher load fractions. In addition, the content of volatile organic compounds increased as the content of bamboo fibers increased, which is thought to be due to the volatile organic compounds generated during the manufacturing process of the composite material being present in the composite material without escaping from the pores of the bamboo fibers and volatilizing at a certain temperature. As a result of confirming the physical properties of the composite, it is considered that the optimal mixing condition is 30wt% of bamboo fiber for the composite produced by varying the amount of bamboo fiber composite. In the future, it is thought that follow-up experiments to confirm and improve the pre-treatment conditions for reducing the content of volatile organic compounds in the manufactured composite material are possible.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.469-481
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• 2014

IIn vitro antimicrobial and anti-inflammatory activities of nargenicin and its derivatives were investigated. Nargenicin, an unusual macrolide antibiotic with potent anti-MRSA (methicilin-resistant Staphylococcus aureus) activity, was purified from the culture broth of Nocardia sp. CS682. And variety of novel nargenicin derivatives was synthesized from nargenicin. Two compounds (4 and 5) exhibit a broad spectrum of antimicrobial activities against infectious bacteria. The antimicrobial activity of derivatives against fifteen organisms was assessed using the minimum inhibitory concentration (MIC). The MIC values were in the ranges of $0.15{\sim}80{\mu}g/mL$ (w/v) for compound 1 and 2, $5{\sim}80{\mu}g/mL$ (w/v) for compound 3, $1.25{\sim}40{\mu}g/mL$ (w/v) for compound 4, and $1.25{\sim}80{\mu}g/mL$ (w/v) for compound 5, depending on the pathogens studied. In vitro, we investigated cytotoxicity and inhibition of nitric oxide (NO) production of synthesized compounds 1-5 in Raw 264.7 cells. LPS-induced nitric oxide releases were significantly blocked by compound 3, 4 and 5 in a dose-dependent manner. At high concentrations ($5{\mu}g/mL$) compound 5 inhibited the NO production by 95%. Compound 4 inhibited the release of NO in LPS-activated Raw 264.7 cells by 75% at the concentration of $10{\mu}g/mL$. Compound 3 inhibited the release of NO in LPS-activated Raw 264.7 cells by 65% at the concentration of $100{\mu}g/mL$. On the other hand, nargenicin, compound 1 and 2 did not inhibit NO production. These results demonstrated that compound 4 and 5 displayed antimicrobial activity and blocked LPS-induced pro-inflammatory mediators such as NO in macrophages, which might be responsible for its therapeutic application.

• Journal of the Korean Chemical Society
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• v.10 no.1
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• pp.1-3
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• 1966

The organic yields (i.e. fraction of nuclear events resulting in organic compound formation) of the radioative neutron capture reactions of halogens in purified bromobenzene have been determined varying extraction time, at $100^{\circ}C$ for thermal effect, varying irradiation time, varying neutron flux and with additional U. V. irradiation. Among the important results are; (1) The organic yields show no remarkable fluctuations with time following neutron irradiation; (2) The organic yields show no change with thermal energy; (3) The organic yields of degassed samples are same in different length of irradiation time whereas the yields of the samples in open air appear to increase with increasing time of irradiation (4) The organic yields increase remarkably with increased neutron flux; (5) The organic yields show a sharp increase by additional U. V. irradiation after neutron irradiation.

• Journal of Magnetics
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• v.16 no.3
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• pp.318-321
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• 2011

A new Fe-based amorphous compound powder was prepared from Fe-Si-B amorphous powder by crushing amorphous ribbons as the first magnetic component and Fe-Cr-Mo metallic glassy powder by water atomization as the second magnetic component. Subsequently by adding organic and inorganic binders to the compound powder and cold pressing, the new Fe-based amorphous compound powder cores were fabricated. This new Fe-based amorphous compound powder cores combine the superior DC-Bias properties and the excellent core loss. The core loss of 500 kW/$m^3$ at $B_m$ = 0.1T and f = 100 kHz was obtained When the mass ratio of FeSiB/FeCrMo equals 3:2, and meanwhile the DC-bias properties of the new Fe-based amorphous compound powder cores just decreased by 10% compared with that of the FeSiB powder cores. In addition, with the increasing of the content of the FeCrMo metallic glassy powder, the core loss tends to decrease.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1587-1592
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• 2006

We report the preparation, structure and magnetic properties of a new pillared complex, copper(II) hydroxy-1,4-butanedisulfonate, $Cu_2(OH)_3(O_3SC_4H_8SO_3)_{1/2}$. The titled compound was obtained by anion exchange, using copper hydroxyl nitrate $(Cu_2(OH)_3NO_3)$ as the starting material. According to the XRD data, this compound exhibits a pillared layered structure with organic layers tilted between the copper hydroxide layers with a tilt angle of $21.8^{\circ}$. FTIR spectroscopy confirms total exchange of nitrate by the sulfonate and indicates that the sulfonate functions are linked to the copper(II) ions with each aliphatic chain bridging the adjacent hydroxide layers. According to the dc and ac magnetic measurements, the title compound is a metamagnet consisting of spin-canted antiferromagnetic layers, with a Neel temperature of 11.8 K.

• Journal of Korea Foresty Energy
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• v.22 no.2
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• pp.18-25
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• 2003

Bamboo vinegar was prepared from China-grown bamboo (Phyllostachys pubescens) using simple kiln (400 - 500 $^{\circ}C$), and its physical properties and chemical components were investigated and compared to those of Korea-grown bamboo vinegar. The physical properties of China-grown bamboo vinegar were as follows: Baume specific gravity 4.5, organic acid 9.9%, pH 2.8, tar 3.1% and refractive index 13.1%, respectively. The main components of the bamboo vinegar were acetic acid, 1-hydroxyl-2-propanone, methanol, propionic acid, 1-hydroxyl-2- butanone. There was no significant difference between the components of Korea- and China-grown bamboo vinegars. Total organic materials in China-grown bamboo vinegar were 14.8%, and organic acids (acetic acid, formic acid, propionic acid, and butanoic acid) consisted of 9.0%. These acids corresponded to 61% of total organic materials. Neutral and phenolic compounds consisted of 4.5% and 0.8% of the bamboo vinegar, which were correspond to 6% and 31% of total organic materials, respectively. The physicochemical properties of traditional Chinese bamboo vinegar indicated that it was collected at low temperature and aged for a long time.