• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2001년도 학술논문발표회
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• pp.70-75
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• 2001

There is a problem to be solved for improvement of durability and safety for concrete When the waterproofing and anticorrosive work of main concrete are design, the material a of construction need to be correctly applied to appropriate circumstance conditions. Epoxy mostly been used for concrete water tank structure. Lately, lots of subjects on adaption res in mortar for waterproofing and anticorrosive are under discussion. Then, we attempt to approach by evaluating and comparing every capabilities with waterproofing materials in this experiment. Capability evaluation items include the bond age and curing conditions, the bond strength after accelerated weathering test and fret impact resistance, a mount of water, seepage quan Through the experiment analysis, we found that waterproofingtity, drinking water chemicals resistance. and anticorrosive resin mortar used with glass fiber cloth, inorgar material is dominantly superior to other waterproofing materials. According to this paper, we suggest the resin mortar as a new surface treatment material water tank structure.

• 한국자원식물학회지
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• 제5권1호
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• pp.11-23
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• 1992

The experiments tvere carried out to different temperature which affected growth, yield, proximate and antitumor activity in the Codonopsis lanceolata. Growth of aerial part and subterranean partwere best at 2$0^{\circ}C$ and lower 3$0^{\circ}C$. Components of fat, protein and fiber were best at 3$0^{\circ}C$. Wild C.fonceoforo had higher contents of fat, protein, fiber and ash as compared with cultur'ed C.lanceolataArginin was predominant amino acid in both wild and cultivated C.laceolata No significant differ-ence in the mineral contents was found between the wild root and the cultivated at 30'c inbiotronroom. No minerals difference in the contents was found between the cultivated temperature.The content of elements of inorganic metal differs according to the part. C. lanceolata were subjectedto preliminary antitumer screening test with Sarcoma 180 ascites and screening on V-79 cell. Thisexperiments were conducted in accordance with the total packed cell volume method and cytotoxicity method.

• 펄프종이기술
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• 제43권2호
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• pp.66-71
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• 2011

Biocomposites were fabricated with biodegradable polymers and natural fibers. Biocomposites have benefits of low cost, low density, and biodegradability over inorganic fiber composite, and give comparable strength properties. Hydrophobic polymer used for sizing in paper industry, AKD (Akenyl Keten Dimer), was applied to natural fibers, red algae fibers (RAF) in this study, to make fiber surfaces more compatible to hydrophobic nature of matrix polymers. Composites with RAF, kenaf, glass fibers, and carbon fibers have been fabricated by a compression molding method and their thermo-mechanical properties have been studied. Also, the thermal dimensional stability test was done from at 30 to $100^{\circ}C$. The storage moduli and the thermo-mechanical stabilities of polypropylene and poly lactic acid based biocomposites were improved by reinforcing with the RAF and much more with AKD treated fibers. Dimensional stability of biocomposite was also markedly improved by AKD pretrement on RAF.

• 한국식품조리과학회지
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• 제22권6호통권96호
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• pp.957-965
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• 2006

This research was conducted to examine the usability of Dangui (Angelica gigas Nakai, Root) and Seungumcho (Angelica gigas Nakai, Leaf) as functional food in aspects of their functional components and nitrite scavenging ability. Analysis of proximate composition showed that Dangui contains more moisture, crude lipid and crude protein than Seungumcho. On the other hand, Seungumcho contains more than twice mont of crude ash and crude fiber than Dangui. Dangui showed higher contents in phosphorus, iron, magnesium, and Seungumcho showed higher contents in copper, calcium, sodium, potassium compare to each other. Substances such as calcium, magnesium and iron that showed high contents in Dangui and Seungumcho are the most important inorganic substances. Total dietary fiber(TDF) of Dangui, sum of IDF and SDF, was 24.2%, and Seungumcho showed 28.18%. vitamin C contents of a 29.690.33 mg/100g appeared only in Seunggumcho. Total phenol contents of Dangui was 0.100${\pm}$002% and that of Seungumcho 0.0900${\pm}$008%. Nnitrite Scavenging ability of both water soluble and methanol soluble extracts were more than 90% at pH 1.2, and it decreased as pH level adjusted to pH 4.2, pH and 6.0.

• 폴리머
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• 제36권6호
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• pp.733-738
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• 2012

광전소자용 유연기판으로 사용되는 폴리에틸렌나프탈레이트 필름의 치수안정성 향상을 위하여 첨가된 유리 비드와 유리 섬유가 필름의 열팽창계수와 광투과도에 미치는 영향을 살펴보았다. 첨가된 무기 필러의 함량이 증가할수록 열팽창계수와 광투과도가 감소함을 알 수 있었다. 무기 필러의 크기, 입도 분포 또한 유연기판의 치수안정성과 광투과도에 영향을 미치는 주요한 요인임을 확인할 수 있었다. 본 연구 결과, 유연기판으로 사용 가능한 85% 이상의 광투과도를 유지하면서 폴리에틸렌나프탈레이트의 고유 치수안전성을 50% 이상 감소시키는 무기 필러의 함량은 5 wt% 내외임을 알 수 있었다.

• 펄프종이기술
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• 제46권4호
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• pp.1-10
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• 2014

In papermaking industry, inorganic fillers are widely used for the purpose of improving opacity, brightness, printability, uniformity and dimensional stability. They are also useful for production costs and energy savings. In the past, inorganic fillers in papermaking industry only focused on micro-scale but recently, new trials on nano-powdered technology are applying. Even nano-powdered fillers are rapidly utilized for improving the optical and surface properties in coating and surface sizing, there still have some problems in wet-end process due to poor dispersibility and retention. In this study, nano-particled calcium carbonate was produced by milling the PCC and its applicability between micro sized and nano sized calcium carbonated was compared in wet-end process, and finally the sheet properties were evaluated. Nano-PCC was not retained in sheet structure without applying retention system, but with retention system nano-powdered PCC was absorbed on fiber surface with expanding the fiber networks. The application of PAM-bentonite system has resulted in high ash retention and bulky structure for copier paper, and good optical properties in brightness and opacity. However, it required to solve the weakness of low tensile property due to interruption of hydrogen bonding by nano fillers.

• 한국광물학회지
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• 제28권2호
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• pp.165-171
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• 2015

부산과 울산의 중심지역에 대해 공기 중의 분진시료를 채취하여, 위상차현미경, 위상차분산현미경, 주사전자현미경 등으로 석면을 분석한 결과, 석면은 검출한계 이하로서 확인되지 않았다. 공기중의 분진시료에는 섬유상물질이 다수 포함되었으나, 이들은 대부분 유기질 섬유인 것으로 나타났다. 무기질 섬유물질로는 암면, 세라믹섬유, 석고 등이 소량 포함되었으며, 비섬유상인 석영, 방해석, 장석등의 광물도 가끔 관찰되었다. 국내의 공기 중 분진의 석면분석은 주로 위상차현미경으로 관찰하는 것으로 규정되어 있으나, 이것만으로는 석면의 식별이 불가능한 것으로 나타났다. 따라서 일본 JIS법과 같이 저온회화 처리 장치에 의한 유기물질 제거 후에 분산염색법으로 석면을 식별하고 계수하는 것이 효율적인 것으로 사료된다.

• 한국염색가공학회지
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• 제7권4호
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• pp.61-73
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• 1995

Inorganic salts have negative or positive effects on the rates of many chemical reactions and also the rates of acidic and alkaline hydrolysis of carboxylic esters. The direction of salt effects on the hydrolysis of ester depends on the charge of esters. It is expected that the rate of the alkaline hydrolysis of Poly(ethylene terephthalte)(PET), polymeric solid carboxytic polyester with carboxyl end group at the polymer end, is also influenced by inorganic salts. In the present work, to clarify the effect of divalent cations on the alkaline hydrolysis of PET, many salts with divalent cations like $MgCl_{2},CaCl_{2},SrCl_{2},BaCl_{2},$ were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous NaOH solution having many salts under various conditions. Some conclusions obtained from the experimental results were summarized as follows. Many salts with various divalent cations increased or decreased the reaction rate of alkaline hydrolysis of PET depending on their electrophilicity, hydration property, ability of ion pair formation, solubility, and the degree of interactions between divalent cations and anions, etc. The hydrolysis was interrupted in the order of $Ca^{+2} and was generally accelerated in the order of $Ba^{+2}. It was inferred from the increase in ΔS$^*$and the decrease in the ΔG$^*$that the divalent cations $Sr^{+2}$ and $Ba^{+2}$attracted by PET increased the collision frequency between carbonyl carbon and $OH^{-}$ion and then accelerated the reaction rate. $Mg^{+2}$and $Ca^{+2}$decreased the reaction rate because of their strong interaction with $OH^{-}$.

• Membrane and Water Treatment
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• 제14권2호
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• pp.85-93
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• 2023

Membrane separation is widely used for several applications such as water treatment, membrane reactors and climate change. Cross-linked organic-inorganic hybrid polyvinylidene fluoride (PVDF) / Tetraethyl orthosilicate (TEOS) was adopted for the preparation of optimized hollow membrane (HFM) for membrane distillation or other low pressure separators for mechanical properties and permeability under varying pretreatment schemes. HFMs were prepared on semi-pilot membrane fabrication system. Novel adopted post-treatment schemes involved soaking in glycerol, magnesium sulphate (MgSO₄), sodium hypochlorite (NaOCl), and isopropanol for different durations. All fibers were characterized for morphology using a scanning electron microscope (SEM), surface roughness using atomic force microscope (AFM), elemental composition by examining Energy Dispersive Spectroscopy (EDS), water contact angle (CA°) and porosity. The performance of the fibers was evaluated for pure water permeation flux (PWF). Post-treatment with MgSO₄ gave the highest both tensile modulus and flux. Assessment of properties and performance revealed comparable results with other organic-inorganic separators, HF or flat. In spite of few reported data on post treatment using MgSO₄ in presence of TEOS, this proves the potential of low cost treatment without negative impact on other membrane properties. The flux is also comparable with hypochlorite which manifests substantial precaution requirements in actual industrial use.The relatively high values of flux/bar for sample treated with TEOS, post treated with MgSO₄ and hypochlorite are 88 and 82 LMH/bar respectively.

• 한국식품과학회지
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• 제40권6호
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• pp.680-685
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• 2008

본 연구에서는 생식용으로 많이 이용되는 땅두릅이 적정 출하시기가 끝나면 기온상승으로 인하여 생식용으로 부적합한 제품이 다량 발생하고, 땅두릅 잎 또한 가축의 사료로 쓰이거나 그대로 버려지고 있어 가공적성에 맞는 상품개발이 필요한 상황이어서 이용가치를 높이는 방안으로 땅두릅과 땅두릅잎에 대한 기초자료를 마련하고자 영양 및 기능성 성분을 조사하고자 하였다. 땅두릅과 땅두릅잎의 일반성분 및 무기성분, 비타민 모두에서 비교적 높은 결과를 나타내었는데, 일반성분에 있어서 땅두릅은 수분이 94.50%로 나타났으며 탄수화물이 2.20%, 조섬유가 0.90%로 나타났고 조단백질은 1.60%, 조지방은 0.20%, 회분은 0.70% 이었다. 또한 땅두릅잎은 수분이 85.70%, 탄수화물이 7.00%이었고 조섬유가 1.50%, 조단백질이 4.30%, 조지방이 0.30%, 회분이 1.20%로 나타났다. 특히 무기성분은 K가 땅두릅에 264.00 mg%과 땅두릅잎에 172.00 mg%으로 가장 많이 함유되어 있었으며 다음으로 Ca, P, Na, Mg순으로 나타났다. 비타민은 베타카로틴이 가장 많았고 다음으로 비타민 C의 함유량도 많음을 알 수 있었다. 조사포닌 함량은 땅두릅이 63.7 mg/g, 땅두릅잎은 63.5 mg/g으로 비교적 많은 조사포닌을 함유하고 있었다. 항산화활성능은 페놀성 화합물이 각각 58.25, $79.32{\mu}g/mg$이었고 총 플라보노이드는 각각 11.25, $15.36{\mu}g/mg$로 나타났으며 전자공여능은 32.23, $28.06{\mu}g/mg$으로 우수한 소거능을 가짐을 확인하였다. 또한 식이섬유 함유량은 땅두릅의 경우 총 식이섬유 함량이 2.13%, 땅두릅잎은 총 식이섬유가 5.98%로 비교적 높은 식이섬유가 존재함을 확인하였다. 총 클로로필 함량도 땅두릅이 92.58 mg%와 땅두릅잎이 147.25 mg%로 높게 함유되어 있는 것이 확인되었다.