• Elastomers and Composites
• /
• v.50 no.2
• /
• pp.87-91
• /
• 2015

Cure characteristics of non-oil-extended solution SBR (S-SBR_NO) and oil-extended solution SBR (S-SBR_ EO) compounds reinforced with silica/carbon black were investigated. Minimum and maximum torques of S-SBR_ EO compounds were much smaller than those of S-SBR_NO ones. Delta torques of S-SBR_NO compounds were greater than those of S-SBR_EO ones, and that of S-SBR_NO compound increased with increase in the 1,2-unit content. Optimum cure time ($t_{90}$) of S-SBR compound decreased with increase in the 1,4-unit content, whereas it increased with increase in the 1,2-unit content. Cure rate index of S-SBR compound increased with increase in the 1,4-unit content, whereas it decreased with increase in the 1,2-unit content. Comparing cure characteristics of S-SBR_NO and S-SBR_EO compounds with the same 1,2-unit content, $t_{90}$s of S-SBR_EO compounds were longer than those of S-SBR_NO ones and cure rate indices of S-SBR_EO compounds were smaller than those of S-SBR_NO ones.

• Journal of the Korean Society of Food Culture
• /
• v.30 no.6
• /
• pp.766-772
• /
• 2015

This research was conducted to investigate the effect of essential oil (EO) from Artemisia Princeps Pampanini on quality of tomato during storage. EO was extracted by steam distillation and diluted by 1 and 2%. Total phenolic contents and antioxidative activities of EO were analyzed. Tomato was packaged corrugated box covered with polypropylene (PP) film containing EO (1 and 2%) and then stored at room temperature for 10 days. During storage, appearance, weight loss rate, soluble solid contents, pH and a (redness) value were measured for tomato. Total phenolic contents of EO increased in a dose-dependence. The DPPH and ABTS radical scavenging activities also showed a concentration-dependent increase. The weight loss rate was lowest using the film packaged in 1% EO. During the storage period, soluble solid contents and pH increased in all treatments. The a value increased regardless of EO concentration in films. Especially, tomato packaged with EO film showed a lower a value than non EO-packaged ones. This result suggests that application of EO to film is effective for tomato quality preservation.

• Macromolecular Research
• /
• v.12 no.3
• /
• pp.251-257
• /
• 2004

The nature of the nematic liquid crystal (LC) alignment induced by the rubbed polyimide (PI) alignment layers (ALs) and the electro-optical (EO) properties of the LC cells are expected to depend on the chemical and physical features of the PI. By employing five pyromellitic dianhydride (PMDA)-type PIs having different functionalities, we have studied the effects of the PI's structure and chemistry on the alignment characteristics and the cell's EO properties. Increasing the flexibility of the PI increases the pretilt angle and tends to improve the alignment stability. On the other hand, the rigid, fluorinated PI displays poor stability for LCs and induces a less stable/uniform LC alignment and, subsequently, a small pre tilt angle. It also transpired that fluorination of the PI deteriorated the voltage-transmittance characteristics and the voltage holding ratio; increasing the flexibility of the PI structure improves these EO properties. The finding that the qualitative trends for the PI's functionalities are similar for both the alignment and EO properties suggests that the EO properties are closely related to the alignment characteristics, which are determined by short-range interactions between LC and PI molecules.

• Journal of Environmental Science International
• /
• v.1 no.1
• /
• pp.69-76
• /
• 1992

The effects of $Ca_{2+}$ ion on the formation of micelle colloid of nonionic surfactants, nonylphenol-(ethylene oxide)n [NP-(EO)n: n= 11, 40, 100) were investigated by the iodine solubilization method. The characteristics of spectra depended on the concentration of $Ca_{2+}$ ion and the number of EO unit. Above CMC(critical micelle concentration), the intensity of the CT (charge transfer) band by the addition of $Ca_{2+}$ ion for the NP-(EO)11 and NP-(EO)40 increased and when decreased and for the NP-(EO)In continuously increased. The increase in the intensity of CT band were attributed to the compactness of micelle in the presence of $Ca_{2+}$ ion. These phenomena may be explained by the fact that the linear ethylene oxide (EO) chain, relatively free to assume various configuration in aqueous solution, could form a pseudo-crown ether structures capable of forming complexes with $Ca_{2+}$ ion.

• Korean Journal of Remote Sensing
• /
• v.28 no.6
• /
• pp.671-682
• /
• 2012

Strong backscattering features from high-resolution Synthetic Aperture Rader (SAR) image provide useful information to analyze earth surface characteristics such as man-made objects in urban areas. The SAR image has, however, some limitations on description of detail information in urban areas compared to optical images. In this paper, we propose a new classification method using a fused SAR and Electro-Optical (EO) image, which provides more informative classification result than that of a single-sensor SAR image classification. The experimental results showed that the proposed method achieved successful results in combination of the SAR image classification and EO image characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.05a
• /
• pp.189-192
• /
• 2005

We have investigated the EO characteristics generation of pretilt angle for a nematic liquid crystal (NLC) alignment with photoalignment method on three kinds of photopolymer surfaces using polymer substrates. The LC homogeneous alignment were observed on the PMI3CA (N-(phenyl)maleimide with 3-carbon chain cinnamoyl group) and PMIF (N-(phenyl)maleimide including fluoro cinnamoyl group). However, the homeotropic alignment on the PMI5CA(N-(phenyl)maleimide with 5-carbon chain cinnamoyl group) was obtained. Also, EO characteristics of the flexible photoaligned TN-LCD using PMIF surface are better than that of the flexible TN-LCD using PMI3CA surface. Also, the stable EO performances of flexible photoaligned VA-LCD using the PMI5CA surface was observed.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.12
• /
• pp.1160-1165
• /
• 2011

This study is focused on the structural dynamic responses, i.e., vibration analysis results of the high-accuracy observation multi-axial camera, which is installed and operated for the UAV (Unmanned Aerial Vehicle) and helicopter etc. And, the authors newly suggest a modeling technology of the ball bearing applied to the camera by using three-axis spring elements. The vibration analysis results well agreed to the randum vibration test results. Also, the vibration responses characteristics of the multi-axial camera through the time history analysis of the random vibration were analyzed and evaluated. The above results can be applied to the FE-modeling of the ball bearings used for the space cameras.

• Journal of the Korean Chemical Society
• /
• v.37 no.1
• /
• pp.36-42
• /
• 1993

In the presence of $Ca^{2+}$ ion, the charge transfer (CT) interaction of nonionic surfactants, $nonylphenol-(ethylene oxide)_n\;[NP-(EO)_n; n = 11, 40, 100]$ with iodine in aqueous solution were investigated by UV-visible spectrophotometer. The characteristics of spectra depended on the concentration of $Ca^{2+}$ ion and the number of EO unit. Above CMC, the intensity of the CT band by the addition of $Ca^{2+}$ ion for the $NP-(EO)_{11}$ and $NP-(EO)_{40}$ increased and then decreased, while for the $NP-(EO)_{100}$ continuously increased. The increase in the intensity of CT band were attributed to the compactness of micelle in the presence of $Ca^{2+}$ ion. These phenomena may be explained by the fact that the linear ethylene oxide (EO) chain, to be free configuration in aqueous solution, could form a pseudo-crown ether structures capable of forming complexes with $Ca^{2+}$ ion.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.15 no.3
• /
• pp.253-257
• /
• 2002

A new photoalignment material PNC, pole norbornene-2,3-dicarboxyolyl cholesterol, was synthesized and the electro-optical (EO) characteristics of the vortical-alignment (VA) liquid crystal display (LCD) photoaligned with UV exposure on the PNC surface were studied. EO characteristics of the photoaligned VA-LCD using a UV filter-less method was better than that of the UV filter method on the PNC surface for short UV exposure time. The response time of the photoaligned VA-LCD on the PNC surface without UV filter on the PNC surface is almost the same compared with the rubbing aligned VA-LCD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.07a
• /
• pp.835-838
• /
• 2000

A new photo-alignment material, copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy) chalcone-cholesterol methacrylate) was synthesized and the electro-optical (EO) characteristics for the photo-aligned vertical-aligned (VA)-LC display (LCD) were studied. Good voltage-transmittance (V-T) and response time characteristics for the photo-aligned VA-LCD with polarized UV exposure on the copolymer-1 (2%) surfaces for 1 min. were observed. EO performance for the photo-aligned VA-LCD decreased with increasing UV exposure time on a copolymer surface. Also, excellent V-T and response time characteristics for the photo-aligned VA-LCD with UV exposure on copolymer-2 and copolymer-3 surfaces for 3min. can be achieved.