• Title/Summary/Keyword: 10-diene

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Synthesis of High-energy-density Fuel through Dimerization of Bicyclo[2.2.1]hepta-2,5-diene over Co/HY Catalyst (Co/HY 제올라이트 촉매상에서 Bicyclo[2.2.1]hepta-2,5-diene 이량화를 통한 고에너지밀도 연료 제조)

  • Kim, Jongjin;Shim, Beomseok;Lee, Gayoung;Han, Jeongsik;Jeon, Jong-Ki
    • Applied Chemistry for Engineering
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    • v.29 no.2
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    • pp.185-190
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    • 2018
  • The dimer of bicyclo [2.2.1] hepta-2,5-diene (norbornadiene) can be used as a high-energy-density fuel. The purpose of this study is to investigate the effect of Co loading on the acid properties of HY zeolite catalyst and the catalytic activity in norbornadiene dimerization. When the cobalt was loaded on the HY zeolite catalyst, the amount of acid sites did not change, but the acid strength weakened. This can be attributed to the decrease in $Br{\ddot{o}}nsted$ acid site and the increase in Lewis acid site. The norbornadiene conversion and yield of norbornadiene dimer over the Co/HY catalyst showed higher than those over the HY zeolite catalyst. The higher activity of the Co/HY catalyst can be ascribed to the higher amount of Lewis acid sites over the Co/HY catalyst. Density and calorific values of the norbornadiene dimer prepared by using the Co/HY catalyst agreed well with the known values in the literature. It was confirmed that the norbornadiene dimer prepared in this study can be used as a high-energy-density fuel.

Melt Grafting of Citraconic Acid onto an Ethylene-Propylene-Diene Terpolymer (EPDM) -Effect of Reaction Conditions and Initiator Type on the Melt Grafting of Citraconic Acid onto EPDM- (EPDM고무와 씨트라코닉산의 melt grafting - 반응조건과 개시제에 따른 영향 연구 -)

  • Kim, Jung-Soo;Bae, Jong-Woo;Lee, Jin-Hyok;Oh, Sang-Taek;Kim, Gu-Ni;Lee, Young-Hee;Kim, Han-Do
    • Elastomers and Composites
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    • v.48 no.1
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    • pp.39-45
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    • 2013
  • Melt grafting of citraconic acid (CCA) onto an ethylene-propylene-diene terpolymer (EPDM) with various peroxide initiators was performed using a Haake Rheocorder. Finding the optimum running condition and concentration is critical for effective grafting and performance of grafted material. Therefore, this study focused on the effects of mixing (reaction) condition and monomer/initiator dosages on the grafting degree, grafting efficiency and crosslinking degree (gel content), melt flow index and mechanical properties of CCA-g-EPDM. As the grafting degree/crosslinking degrees increased, the tensile strength increased significantly, but elongation at break and melt flow index decreased. The initiator 2,5-dimethyl-2,5-di(tert-butyl peroxy)-hexane (T-101) appeared to meet for the best grafting(2.31%). The grafting degree increased markedly with increasing monomer CCA/initiator T-101 contents. The grafting degree also increased with increasing mixing temperature/time, and then leveled off or decreased/increased a little. The optimum monomer/initiator dosages and reaction temperature/time were found to be about 5/0.05 wt% and $180^{\circ}C$/15min, respectively.

Identification of volatile flavor compounds in Jeju citrus fruits (제주감귤류의 휘발성 향기성분의 확인)

  • Hong, Young Shin;Kim, Kyong Su
    • Food Science and Preservation
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    • v.23 no.7
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    • pp.977-988
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    • 2016
  • The volatile flavor compounds in five Jeju citrus fruit varieties (Cheonhyehyang, Hallabong, Jinjihyang, Hwanggeum hyang and Redhyang) were extracted by simultaneous distillation-extraction (SDE) using solvent mixture of n-pentane and diethyl ether (1:1, v/v) and analyzed by using gas chromatography-mass spectrometry (GC-MS). The number of aroma compounds were identified with : 104 (4,939.77 mg/kg) in Cheonhyehyang, 98 (3,286.38 mg/kg) in Hallabong, 105 (3,317.56 mg/kg) in Jinjihyang, 102 (4,293.39 mg/kg) in Hwanggeumhyang, and 108 (4,049.94 mg/kg) in Redhyang. The detected main volatile compounds were; limonene, sabinene, ${\beta}$-myrcene, ${\alpha}$-pinene, ${\beta}$-pinene, linalool, 4-terpineol, ${\alpha}$-terpineol, (E)-${\beta}$-ocimene and ${\gamma}$-terpinene. Among the identified volatiles compounds, ethyl-benzene, nonanol, 1-p-menthen-9-al, (E)-isocarveol, methyl salicylate, ${\alpha}$-terpinen-7-al, perilla alcohol, and ethyl-dodecanoate were detected in Cheonhyehyang. only Furthermore, ${\beta}$-chamigrene and ${\alpha}$-selinene were in Hallabong only; 3-hydroxybutanal, (E)-2-nonenal, isoborneol, octyl acetate, (E)-2-undecenal, ${\beta}$-ylangene and guaia-6,9-diene in Jinjihyang. ${\rho}$-Cymenene, ${\beta}$-thujone, selina-4,11-diene and (E,E)-2,6-farnesol in Hwanggeumhyang only; and ${\rho}$-cymen-8-ol, bornyl acetate, carvacrol, bicycloelemene, ${\alpha}$-cubebene and 7-epi-${\alpha}$-selinene in Redhyang only. This study confirmed the differences in composition and content of volatile aroma components in five varieties of Jeju citrus fruits.

Cure Characteristics, Physical Properties and Ozone Resistance of Butyl Rubber and EPDM Rubber Blends (Butyl고무와 EPDM고무 블렌드의 경화특성, 물리적 성질 및 내오존성)

  • Park, Chan-Young;Hwang, Young-Bea
    • Elastomers and Composites
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    • v.46 no.4
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    • pp.329-334
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    • 2011
  • In general, butyl rubber(IIR : isobutylene isoprene rubber) has excellent gas permeability resistance and impact absorbance property as low resilience elastomer. In this experiment butyl rubber blends with EPDM(ethylene propylene diene monomer) were prepared by mechanical mixing method. Curing behavior, physical properties and ozone resistance etc. were subsequently examined. Measurement results of gas transmission rate test shows that butyl rubber contents above 50 wt% showed significant decrease in gas permeability resistant property. However, in butyl rubber/EPDM blend, EPDM contents above 25 wt% indicates no surface change due to improvement of ozone resistance under the condition of 50 pphm, $50^{\circ}C$, 120 hrs.

Impact of Sound Insulation in a Combine Cabin

  • Kim, Chiho;Jung, Ho Jun;Jo, Jin Seok;Kim, Myong il;Lee, Bongho;Park, Tae Jong;Seo, Kwangwook;Kim, Hyeon Tae
    • Journal of Biosystems Engineering
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    • v.40 no.3
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    • pp.159-164
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    • 2015
  • Purpose: Recently, environmental pollution and safety problems in agricultural production have become important issues. Initially, bio-production machines focused on high production efficiency rather than workers' safety and comfort, but this trend slowly has changed as time went on. Methods: This study was carried out to identify sound efficiently and reliably for noise reduction by using a combine cabin model. Ethylene propylene diene monomer (M-class) rubber (EPDM) was applied to improve noise reduction performance from parts connected directly to the front, rear, left side, and bottom side of the cabin. Results: As a result, an average noise reduction of 1.85 dB was achieved in the normal hearing range between 500 Hz to 2 kHz. Conclusions: Reducing the cabin noise levels can reduce a worker's fatigue, improve working environment, and contribute to future low-noise and high-quality cabin environment.

A Study on Composites of Ethylene-Vinyl Acetate Copolymer and Ethylene-Propylene-Diene Rubber with Aluminum Hydroxide as a Fire Retardant

  • Lee, Yu Jun;Lee, Su Bin;Jung, Jae Young;Lee, Dam Hee;Cho, Ur Ryong
    • Elastomers and Composites
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    • v.51 no.2
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    • pp.93-98
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    • 2016
  • The composites of EVA/EPDM including aluminum trioxide (ATH) as a fire retardant were manufactured for the purpose of improving low temperature property and flame resistance in the rubbery materials. The ratio of EVA to EPDM didn't affect the flame resistance of the rubber composites. The addition of ATH resulted in increase of the flame resistance. In the evaluation of the cold resistance, the increasing EPDM content showed enhancement of cold resistance in the composites due to increasing low Tg EPDM. It was found out that tensile strengths of the composites showed a maximum value at 100 phr of ATH by reinforcing effect, but a minimum value at 200 phr of ATH owing to slippage between the flame retardant by the external stress. In the measurement of solvent resistance in tetrahydrofuran, the increasing ATH content yielded enhancement of solvent resistance by reducing swelling of the composite, and increasing EPDM content also resulted from increase of the solvent resistance by reduction of polarizability as well as increase of crosslink in the composites.

A Study on Physical Properties of EPDM/Polyhedral Oligomeric Silsesquioxane (POSS) Composites (EPDM/POSS(Polyhedral oligomeric silsesquioxane) 복합재료의 물성 연구)

  • Park, Hyun-Ho
    • Applied Chemistry for Engineering
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    • v.32 no.4
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    • pp.472-477
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    • 2021
  • The crosslinking behavior of polyhedral oligomeric silsesquioxane (POSS) containing eight acrylate groups in a cage form in ethylene-propylene-diene rubber (EPDM) peroxide crosslinking, the effect on mechanical properties, and the thermal stability were investigated. An EPDM/POSS composite material was prepared by mixing 0 to 12 parts per hundreds of rubber (phr) of POSS per 100 phr of rubber by content and adding a peroxide crosslinking agent. As a result of crosslinking properties, it was found that the acrylate group of POSS was activated by peroxide and improved the peroxide crosslinking efficiency. Although the dispersion stability of POSS in EPDM/POSS composites was poor, the fracture strength, elongation and thermal stability were improved.

Dentatins: Sesquiterpene Glucosides from lxeris dentata

  • Chung, Ha-Sook;Woo, Won-Sik;Lim, Sook-Ja
    • Archives of Pharmacal Research
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    • v.17 no.5
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    • pp.323-326
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    • 1994
  • Three new sesquiterpene lactone glucosides named dentatins A, B and C were isolated from lxeris dentata and the structures were elucidated as $3{\betha}, {\;}8{\betha}-dihydroxy-(1{\alpha}, 5{\alpha})guainan-10(14)-ene-6{\alpha}, {;\}12-olide-3-O-{\betha}-D-giucopyuranoside{\;}(1), {\;}3{\betha}, {\;}8{\betha}-dihydroxy-(1{\alpha}, {\;}5{\alpha})-guaian-4(15), {\;}10(14)-diene-6{\alpha}, {\;}12-plide-3-O-{\betha}-D-glucopyranoside{\;}(3)$, respectively, on the basis of spectral evidence.

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