• Textile Coloration and Finishing
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• v.28 no.3
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• pp.183-188
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• 2016

The uniformly dispersed p-Aramid chopped fiber in a variety of rubber was investigated. The cross section and surface properties in a variety of rubber were characterized by scanning electron microscopy(SEM), weight, tensile strength, cold resistance measurements. The 1mm p-Aramid chopped fiber better uniformly dispersed than the other p-Aramid chopped fiber. The p-Aramid of lmm chopped fiber showed excellent adhesion in rubber composite because of homogeneous dispersion. Consequently, the best 1mm chopped fiber and rubber improved the strength of the composite.

• Journal of Dairy Science and Biotechnology
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• v.18 no.1
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• pp.61-72
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• 2000

Consumers primarily consider flavor when they take yogurt. Recent researches on yogurt flavor productron its analytical technique have been extensively developed. These studies have provided a better understanding on the role of starter culture microorganisms on flavor formation and degradation. Yogurt volatile flavor compounds produced by the lactic cultures include acetaldehyde, diacetyl, ethanol and organic acid. Among them, acetaldehyde is recognized as a principal flavor component. since yogurt contains a delicate and low intense flavor, mild sample isolation techniques and sensitive identification means might be used. This paper attempts to discuss recent findings in yogurt flavor and to describe the application of yogurt flavor separation techniques. The section on practical aspects of culture selection based on flavor compound production and flavor analysis is also included.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3318-3326
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• 2010

Five new series of 3,4-ethylenedioxythiophene derivatives carrying important pharamacophores, viz., amide, ester, ether and active secondary aryl moieties have been designed and synthesized through multistep reactions starting from thiodiglycolic ester and diethyl oxalate. They have been characterized by elemental and spectral data. All the target compounds have been screened for their anticonvulsant activity at three different models viz. maximal electroshock (MES), subcutaneous metrazole (scMET), and 6 Hz screen and evaluated for their neurotoxicity in rotorod model. Compound 6a emerged as lead with no neurotoxicity. All the five series of compounds are safe in the toxicity studies at the maximum dose of 300 mg/kg of body weight. Amongst the tested compounds, the ester pharmacophore with thioamide fragment has showed better activity than the other analogs.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.303-305
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• 1997

The advantage of application polymer instead of conventional porcelain as the housing material for arrester is that light weight, shorter section length of arrester would be possible due to the use of an insulated hanger (mold compound). also, polymer arrester has very good characteristics in design versatility as well as excellent resistance to moist ingress and pollution performance. The finite element method is widely used to calculate for electromagnetic devices. In this paper, we perform the each conditional analysis of PC with an advanced graphical user interface(GUI) using the vector fields simulator. And we try to analyze electromagnetic fields through the conventional two dimensional analysis in case of high voltage contamination on the electrode of a arrester.

• Journal of Surface Science and Engineering
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• v.32 no.1
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• pp.31-42
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• 1999

The effect was investigated that aluminium in the zinc bath has on the coating adhesion of Hot-rolled Galvanized Iron(HGI) manufactured without pickling process. It is thought that the coating adhesion of HGI manufactured without pickling process is good due to the fact that increasing aluminium content in the zinc bath makes zinc and aluminium diffuse to the cracks or pores in the scale formed through the reduction heat treatment, and Fe-Zn-Al compound with good ductility is formed in the scale layer and plays a role of anchor between zinc coating and substrate. It is possible that HGI with the good coating adhesion was produced without pickling treatment in the zinc bath with more that 3wt% of Al content even at the $550^{\circ}C$ of conventional reduction heating temperature. In creasing the temperature of heating section and aluminium content in the zinc bath prevents the Zn-Fe alloy. The corrosion resistance of HGI manufactured without pickling process is excellent because of the mixed reaction of zinc sacrifice and aluminium passivity film.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4026-4031
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• 2023

In this article, we report a new empirical formula for quick calculation of cross sections of (n, α) reactions with 14-15 MeV neutrons. Cross sections are analysed in terms of the compound nucleus model. A systematic trend for 14-15 MeV neutrons is found in the variation of (n, α) reaction cross sections with the parameters (N - Z + 1), (E_n + Q)^0.5 and N/Z. The empirical relation between the cross sections and these parameters has been obtained, which give fairly good fits with the experimental data. We have also investigated the odd-even effects on (n, α) cross sections considering binding energy systematic of the shell model. The present formula is very useful in predicting of the (n, α) cross sections, where the measurements are not available as well as in testing new experimental data.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.266-277
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• 1995

The adult brown planthopper possesses tow oval shaped compound eyes which, on their ventral borders, curve around the base of the antennae. Compound eye of the adult brown planthopper is recognised apposition eye which each ommatidium is optically isolated from it surroundings, the rhabdoms receiving light only from their own corneal lens. Each ommatidium possesses its own dioptric apparatus formed from the cuticular cornea and an underlying crystalline cone. The retinula cells lying immediately beneath the crystalline cone have their individual rhabdomeres tightly opposed to form one central, closed rhbdom. The rhabdom stretches from the spex of the crystalline cone nearly to the basement membrane and is approximately 110~120 $\mu\textrm{m}$ in length. The crystalline cone is surrounded by a pair of primary pigment cells an these in turn are surrounded by accessory pigment cells. Accessory pigment cells extend beyond the crystalline cone surrounding the retinular cells in the distal region of the eye. The crystalline cone is surrounded by the distal-most regions of the retinula cells show the presence of seven cells and sections taken proximally in the last quarter of the omatidium before the basement membrane is reached, reveal the presence of a small, eighth retinula cell which also contributes to the central rhabdom. Each ommatidium has a central rhabdom formed from the modified inner border of all of the retinula cells. Th rhabdom consists of micrvilli arising from the inner wall of each retinula cell. In cross section th microvilli exhibit a characteristic honeycomb appearance. Pigment cells comprise the primary pigment cells enveloping the crystalline cone, the accessory pigment cells extending from the inner surface of the comea to the basement membrane and the small pigment cells of the basement membrane.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.77-85
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• 2009

Objectives : To determine the discriminative criteria for Atractylodes rhizomes, the experiment of externalinternal characteristics and physicochemical pattern analysis were performed. Methods : External characteristics was observed using stereoscope. The sectioned materials which were covered with parffin were stained by Ju's method. Physicochemical patterns were analyzed using HPLC/DAD. Results : 1. External shape of original plant : Atractylodes maaocephala and A. japonica had relatively long petioles and 3-5 parted leaves. A. macrocephala had big purple flowers whereas A. japonica had relatively small white flowers and pinnate bracts. A. lancea had sessile leaves and white flowers, and the end parts of degenerated stamens were bent. 2. External shape of herbal medicine: A. macrocephala which was fist-shaped rhizome had pa-pillate processes and the cross section was light gray and sulcate. A. japonica and A. lancea were connected-beady or tubercular rhizomes, and the cross sections were both yellow-colored white. However, the cross section of A. japonica was fibrous, the width of cortex was narro-wer than that of stele, and radial shape in cortex was rare, whereas the width of cortex in A. lancea was similar to that of stele in size, and radial shape in cortex was obvious. 3. Internal shape of herbal medicine: A. macrocephala and A. lancea did not have lignified fascicles in cortex. However, the vascular bundles and vessels of A. macrocephala were wedge shaped and radial arrangement, and vascular bundles were densely populated in stele whereas those of A. lancea were repeatedly arranged and thinly extended to cortex. A. japonica had lignified fascicles in cortex and the width of vascular bundles was conspicuously thick with narrow intervals. 4. Physicochemical pattern analysis : A. macrocephala and A. lancea contained atractylenolide I and atractylenolide Ill whereas A. japonica contained atractylenolide I, atractylenolide Ill. diacetyl-atractylodiol, compound-4, compound-5. The three species of Atractylodes rhizomes showed different chromatogram patterns. Conclusions : The results could be used as discriminative criteria for Atractylodes rhizomes and as fundamental materials to researches of further pattern analysis and biological reaction.

• Journal of Welding and Joining
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• v.30 no.2
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• pp.65-69
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• 2012

Environmental and health concerns over the lead have led to investigation of the alternative Pb-free solders to replace commonly used Pb-Sn solders in microelectronic packaging application. The leading candidates for lead-free solder alloys are presently the near eutectic Sn-Ag-Cu alloys. Therefore, extensive studies on reliability related with the composition have been reported. However, the insufficient drop property of the near eutectic Sn-Ag-Cu alloys has demanded solder compositions of low Ag content. In addition, the solder interconnections in automobile applications like a smart box require significantly improved vibration resistance. Therefore, this study investigated the effect of alloying elements (Ag, Bi, In) on the vibration fatigue strength. The vibration fatigue was conducted in 10~1000Hz frequency and 20Grms. The interface of the as-soldered cross section close to the Cu pad indicated the intermetallic compound ($Cu_6Sn_5$) regardless of solder composition. The type and thickness of IMC was not significantly changed after the vibration test. It indicates that no thermal activities occurred significantly during vibration. Furthermore, as a function of alloying composition, the vibration crack path was investigated with a focus on the IMCs. Vibration crack was initiated from the fillet surface of the heel for QFP parts and from the plating layer of chip parts. Regardless of the solder composition, the crack during a vibration test was propagated as same as that during a thermal fatigue test.

• Composites Research
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• v.32 no.6
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• pp.360-367
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• 2019

In order to apply thermoplastic composites using PETG resin to various industrial fields such as bicycle frames and industrial parts, it is necessary to verify the impact resistance, durability, mechanical properties and 3D analysis of the manufactured composite materials. To improve the mechanical properties, durability and impact resistance of PETG resin, an amorphous resin, in this study, compound and injection molding process were carried out enhanced various weight percent POE(polyolefin elastomer). The thermal and mechanical properties of the thermoplastic composites, and the charpy impact strength, The analysis was performed to evaluate the characteristics according to weight percent of POE. Charpy impact strength test was conducted to analyze the impact characteristics, and the fracture section was analyzed after the impact strength test. In the case of POE material-added thermoplastic composites, thermal and mechanical properties tend to decrease, but workability and impact resistance tend to be superior to those of PETG materials.