• Elastomers and Composites
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• v.45 no.1
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• pp.7-11
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• 2010

The acetylene black/silica composite particles were prepared by a simple and fast method using polyethylenimine (PEI) as a coupling agent. The composite particles were produced via the following two steps; adsorption of PEI on the surface of acetylene black particles and synthesis of silica by sol-gel process. The morphology of the composite particles was a core-shell, and a large number of micropores was created after silica was synthesized on the acetylene black surface.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.81-86
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• 1988

The effect of three polyacetylene compounds. panaxydol. panaxynol and panaxytriol isolated from Korean ginseng on $CCI_4-induced$ lipid peroxidation in vitro and in vivo hepatic microsomal lipid peroxidation were investigated. Lipid peroxide levels both in serum and liver and serum enzyme (GOT. GPT. LDH) activities of normal or $CCI_4-treated$ mice and rats were also determined after administration of polyacetylenes. Hepatic microsomal cytochrome P-450 content and activities of aniline hydroxylase and aminopyrine demethylase were measured after treatment of polyacetylenes with or without carbon tetrachloride. As results. treatment with polyacetylenes to control mice did not influence the levels of lipid peroxides and serum enzyme activities while panaxynol did. Panaxynol itself inhibited liver lipid peroxidation in normal mice. Polyacetylene compounds protected hepatic lipid peroxidation and lowered serum lipid peroxide levels induced by $CCI_4$ Polyacetylenes prevented leakage of LDH to serum but elevated GOT and GPT levels caused by $CCI_4$ were not changed by polyacetylene pretreatment. $CCI_4$ caused losses in the content of cytochrome P-450 and activities of aniline hydroxylase and aminopyrine demethylase. When polyacetylenes were treated without $CCI_4$ panaxydol and panaxynol induced aniline hydroxylase and all three polyacetylenes induced aminopyrine demethylase. Cytochrome P-450 contents were not affected by polyacetylenes. In vitro hepatic microsomal lipid peroxidation was inhibited by polyacetylenes and $DL-{\alpha}-tocopherol$ in a concentration-dependent manner.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2003.04a
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• pp.197-202
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• 2003

아세틸렌 화합물의 삼중결합은 2개의 $\pi$-결합을 가지고 있는 전자풍부 화학종으로서 다양한 촉매 system에 의해서 비교적 쉽게 부가중합반응이 진행되며 이를 통하여 공액구조 고분자를 쉽게 제조할 수 있다. 가장 간단한 삼중결합 화합물인 아세틸렌은 다양한 촉매 system에 의해서 쉽게 부가중합반응이 진행되어 분말상의 폴리아세틸렌이 합성되었으며 1974년 일본의 Shirakawa 등은 Ziegler-Natta 촉매의 일종인 Ti(OC$_4$H$_{9}$)$_4$-Al(C$_2$H$_{5}$)$_3$(Al/Ti = 3-4) 촉매 system을 사용하여 실험한 결과 은빛의 필름형 폴리아세틸렌의 합성에 성공하였다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.768-773
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• 2014

In this study, experimental and numerical studies for the synthesis of carbon nanotube(CNT) in methane counterflow diffusion flame have been performed. Methane mixed with acetylene($C_2H_2$) was used as a fuel gas and ferrocene was used as a catalyst for synthesis of CNT. The major parameters was $C_2H_2$ mixing rate and mixing rates were 2 %, 6 %, and 10 %. Characteristics of CNT formation on grid were analyzed from SEM images. the chemical reaction mechanism adopted is GRI-MECH 3.0. Numerical results showed that flame temperature and CO mole fraction were increased with increasing acetylene mixing rate. Experimental results showed that the CNT synthesis in 2% acetylene mixture flame better than that of 6% and 10% acetylene mixture flames. It can be considered that 6% and 10% acetylene mixture flames generated the excessive carbon source and then it interrupted the supplement of the carbon source into ferrocene catalyst. It can be found that the supply of appropriate quantity of carbon source can make effect to synthesis of high purity of CNT.

• Journal of Adhesion and Interface
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• v.4 no.1
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• pp.28-34
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• 2003

Steel tire cords were subjected to plasma polymerization coating of acetylene in order to enhance the adhesion to rubber compounds. Plasma polymerization coating was varied to plasma polymerization coating of acetylene, argon plasma etching+plasma polymerization, or argon plasma. etching+plasma polymerization with Ar carrier gas. Adhesion was evaluated via TCAT samples and compared to those with brass coated tire cord. For durability study, plasma polymer cooled tire cords were aged in lab atmosphere for 1, 3, 5, 10 or 15 days, while TCAT specimens prepared with plasma polymer coated tire cords were aged in distilled water, 10% NaCl solution or $100^{\circ}C$ oven for 1, 2, 3 or 4 weeks. After testing, failure surfaces were analyzed with SEM/EDX. Among the treatments, the highest adhesion was obtained by Ar etching+acetylene plasma. polymerization coating with Ar carrier gas, providing almost same pull-out force as the brass coated tire cords. Upon the aging of the tire cords in the lab atmosphere, brass coated tire cords provided better adhesion than plasma polymer coated tire cords, while the TCAT samples with plasma polymer coated tire cords exhibited similar or slightly superior durability to those with brass coated tire cords.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.131-131
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• 1999

비정질 카본 박막은 다이아몬드와 유사한 높은 경도, 내마모성, 윤활성, 전기절연성, 화학적 안정성, 그리고 광학적 특성을 가진 재료로서 플라즈마 CVD를 이용한 합성방법으로 제조된 박막이 주로 연구되고 있다. 본 연구에서는 마그네트론 스퍼터링을 이용하여 다양한 조건의 카본 박막을 제조하였다. 카본 박막의 제조는 이온빔이 장착된 고진공 증착 장치를 이용하였고 시편의 청정시 사용된 이온빔의 조건은 빔 전압이 500V, 빔 전류는 0.1mA/cm2로 기판 청정을 거친 후 DC 마그네트론 스퍼터링을 이용하여 흑연을 증발시켜 박막을 제조하였다. 기판과 타겟의 거리는 13cm로 고정시킨 후 타겟 전류는 1A로 유지하면서 30분간 증착하였다. 기판은 Si-wafer와 glass를 주로 사용하였으며 기판 인가전압, 아세틸렌 유량, 기판 온도등을 변화시켜가면서 각각 카본 박막을 제조하였다. 비정질 카본박막의 막은 평균 두께는 0.4~1.2$\mu\textrm{m}$이며 SEM을 이용하여 단면의 성장구조를 관찰하였다. 라만 분광분석과 FTIR 분광분석을 통하여 비정질 카본 박막의 결합특성을 조사하였고 scratch tester를 이용하여 박막의 밀찰력을 관찰하였다. 제조된 박막의 두께는 아세틸렌 가스 이용시 1$\mu\textrm{m}$ 이상의 박막의 제조가 가능하였으며 카본 박막의 라만 분광특성은 고체 탄소 물질의 S와 G-peak으로 구성되어 있으며 기판 인가전압, 아세틸렌 가스 유량 변화에 따른 peak의 위치 이동 및 FWHM의 변화를 관찰하였다. RFIR 결과는 아세틸렌 가스의 유량이 증가에 따라 C-H 결합 분포가 증가며 기판 인가 전압이 증가할수록 C-H 결합분포가 감소하는 경향이 나타냈다. 이는 이온 충돌 효과에 따라 결합력이 약한 C-H 결합이 우선적으로 파괴되는 현상으로 생각되어 진다. Scartch tester 측정 결과 박막의 밀착력은 실험조건에 따른 경샹성은 보이고 있지 않으나 10N 정도이며 60N 이상의 강한 밀착력을 가진 박막도 제조되었다.

• Polymer(Korea)
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• v.37 no.1
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• pp.94-99
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• 2013

Polydiacetylene (PDA) is made by photopolymerization of self-assembled diacetylene monomers. If diacetylene monomers are arranged systematically and close enough with distance of atoms, 1,4-addition polymerization will occur by the irradiation of 254 nm ultraviolet rays and then PDA will have alternated ene-yne polymer chains at the main structure. Aqueous solutions of diffused PDA is tinged with blue which shows ${\lambda}_{max}$ 640 nm. Visible color changes from blue to red occurs in response to a variety of environmental perturbations, such as temperature, pH, and ligand-receptor interactions. In this study, we synthesized cationic peptides - PCDA(10,12-pentacosadyinoic acid) liposome using a solid phase peptide synthesis (SPPS) method and prepared liposome solutions at various molar ratios using MPEG-PCDA. When mammalian cells were treated with the liposomes, high transfection efficiency and low toxicity were observed.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.21-26
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• 1986

Polyacetylenes (conjugated poly-ynes) were Isolated from the roots of Panax Ginseng C.A. Meyer by the low pressure preparative liquid chromatography and characterized by spectral analyses. The advantages of the isolation method are the simplicity of the isolation procedure and the much higher yield of poly-ynes compared to the old method.

• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.568-576
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• 2004

Density functional theory calculations are presented for dicyanoacetylene $N{\equiv}C-C{\equiv}C-C{\equiv}N$ and its geometrical isomers. The structures and harmonic frequencies are computed by the BLYP theory employing the 6-311G^{\ast}$ basis set. A variety of isomers are predicted, and the relative energies are compared to estimate their thermodynamic stability.

• Journal of the Korean Institute of Gas
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• v.7 no.1 s.18
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• pp.41-46
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• 2003

The Phase and temperature changes of large clusters formed in a free jet expansion of acetylene in 14atm and 233K has been studied. The cluster has been treated as a sphere composed of many shells. A mean diameter of 4.88 microns was obtained by modeling the experimental cooling curve of clusters based on evaporation and heat conduction theory.