• Title/Summary/Keyword: chemical restoration

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An Effects of a New PGE1: Lipo-AS013 on Blood Flow and Survival of Skin Flap (새로운 PGE1인 Lipo-AS013이 피판의 혈류와 생존에 미치는 영향)

  • Seul, Chul Hwan;Choi, Jong Woo;Chi, Yong Hoon;Tark, Kwan Chul
    • Archives of Plastic Surgery
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    • v.32 no.1
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    • pp.5-11
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    • 2005
  • Prostaglandin $E_1$($PGE_1$) is known to have various physiological action such as vasodilatation, decrease of blood pressure, angiogenesis, inhibition of platelet aggregation and so forth. $PGE_1$ has been developed in many different formulations in order to overcome its chemical instability and deactivation in the lungs when administered parenterally. Lipo-AS013 is a potent drug with higher chemical stability and greater vascular wall targeting than others. The study was done on $3{\times}10cm$ model flap of dorsal skin of Sprague-Dawley rats and the flap perfusion survival were observed and documented. The flap treated with Lipo-AS013 beforehand was given intravenously Sodium fluorescein 10 minutes later, and then Percent Dye Fluorescence Index(% DFI) was calculated. The results were compared to a control group and the group administered locally epinephrine.. In the control group, the % DFI and flap survival rate increased from $54.1{\pm}6.7$ to $65.0{\pm}2.6$(p<0.01) while in Lipo-AS013 group from $55.3{\pm}2.2$ to $67.4{\pm}1.9$(p<0.01), respectively. In the epinephrine group, the % DFI(p<0.05) and flap survival rate(p<0.001) decreased. In the both epinephrine and Lipo-AS013 group Percent DFI and flap survival rate are comparable with the control group.The result indicates that the potent Lipo-AS013 enhances the blood flow and flap survival. This highly potent Lipo-AS013 may have targeting ability and accumulate $PGE_1$ onto the vascular walls. A quantitative analysis of fluorescence on the skin surface is a reliable tool to measure the blood perfusion into an ischemic flap and its viability. Further comparative study with conventional $PGE_1$ and Lipo-$PGE_1$ is needed in order to clarify the action and efficiency of Lipo-AS013.

Lacquer as Adhesive : Its Historical Value and Modern Utilization (접착제로서의 옻; 역사성과 현대적 활용)

  • Jang, Sung Yoon
    • Korean Journal of Heritage: History & Science
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    • v.49 no.4
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    • pp.114-125
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    • 2016
  • Lacquer is one of the most widely used natural resin in East Asia since Neolithic Age. As a major ingredient of lacquerware, lacquer is waterproof, insect-proof and rot-proof to be durable and anti-abrasion, generally utilized for mainly painting purpose. According to lacquerware excavated from several sites of Japan and China, lacquerware seems to appear in Neolithic Age. On the other hand in case of excavation research in Korea, lacquerwares are found after the Bronze Age. The initial purpose of lacquer is estimated to be adhesive, regarding the literatures mentioning bitumen(Yeoksceong ), animal glue(Kyeo) and egg alumen(Nanbaek). Especially piece of jar coffin unearthed in Pyeongtaek Daechu-ri site had trace of restoration by lacquer and hemp as an evidence of lacquer for adhesion in Pre-Three Kingdoms period. Since then a trend to restore the broken ceramics with lacquer and decorate with golden foil lasted especially in Joseon Dynasty. In the field of gold plated lacquer method, mother-of-pearl inlaying technique for lacquerware and restoration of buildings, lacquer is still used as adhesive. Due to matter of reversibility lacquer is being avoided for conservation and restoration of cultural heritage. Lacquer as a traditional material for adhesive since ancient times, however, has advantage in adhesion strength and durability. Because synthetic resin adhesive has problem of emission of volatile organic compounds and aging over time, lacquer receives attention recently. On the contrary, by combination adhesive from mixing lacquer and animal glue, already proved the possibility of applicability and chemical modification. A research to utilize lacquer as modern paint or functional material is also conducted continuously also in China and Japan. To put traditional material into practical use and modernize, chemical research from the molecular level of the lacquer is necessary in the near future.

A Study on the Application of Pre-Chemical Treatment on the Decentralized Domestic Wastewater Reclamation System (도시의 분산형 생활오수 재생시스템에 화학적 전처리공정도입에 관한 연구)

  • Lee, Sang-Woo;Park, Young-Mi;Seo, Gyu-Tae
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.1
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    • pp.115-121
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    • 2006
  • The purpose of this study was to investigate applicability of pretreatment on the existing biological treatment for domestic wastewater reclamation. From Jar Tests, it was found that optimum dosage of coagulant was PAC 0.5mg/L and $FeCl_3$ 180mg/L for urban sewage. In this study, PAC 0.5mg/L was selected considering sludge production and the amount of coagulant required. In a continuous experiment performed with combining chemical coagulation and biological treatment, a considerable removal efficency was obtained in term of BOD, SS, T-N, T-P and ABS. When the raw sewage was supplied into the pre-chamical treatment facility, the removal of BOD and SS was 48.3% and 81.1%. However T-N removal was very low which means T-N consists of $NH_3-N$ mostly. T-P was almost completely recluced by the chemical addition. The effluent BOD & SS was 57~76 and 21~43mg/L, which could reduce the size of biological treatment facility. From the cost estimation pre-chemical treatment could save around half of the area required for biological treatment with post ceagulation.

Toxicity Evaluation of Asarum Sieboldii Extract for Human's Safety (인체안전성을 위한 족두리풀 천연추출물의 독성평가)

  • Kim, Young Hee;Jo, Chang Wook;Hong, Jin Young;Lee, Jeung Min;Kim, Soo Ji;Jeong, So Young
    • Journal of Conservation Science
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    • v.33 no.4
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    • pp.255-266
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    • 2017
  • Chemically derived pesticides have been used to prevent biological damage to domestic cultural property. However, their use is gradually being restricted due to the harmful effects on the human body and environment. Therefore, there is a growing interest in the search for new antifungal biopharmaceuticals whose safety has been confirmed by toxicity evaluation through animal experiments. This paper presents methods of toxicity evaluation of natural biocides using Sprague-Dawley rats and New Zealand White (NZW) rabbits. Safety of the natural biocide extract of Asarum sieboldii was evaluated using single-dose oral and dermal toxicity tests in Sprague-Dawley rats, and eye and skin irritation tests in NZW rabbits. The extract has proven antimicrobial and insecticidal activities against wood-rotting fungi and termites. After single oral administration to rats, the $LD_{50}$ values were determined to be over 4,000 and 2,000 mg/kg for males and females, respectively. After single dermal administration to rats, the $LD_{50}$ values exceeded 10,000 mg/kg for both males and females. The extract was identified to be non-irritant to the rabbit eye, and only slightly irritant to the rabbit skin. In this study, we confirmed the safety of the A sieboldii extract through animal testing. Due to the harmfulness of humidifier disinfectants, focus is on the safety of chemical pesticides, and toxicity evaluation is suggested as the basic method for hazard evaluation.

A Subcutaneous Lipoma in a Male Red Fox (여우에서 피하지방종의 진단)

  • Jeong, Dong-hyuk;Yang, Jeong-jin;Kong, Joo-yeon;Lee, Bae-keun;Lee, Je-wook;Park, Se-jin;Lee, Seung-yong;Seok, Seong-hoon;Hong, Il-hwa;Lee, Hee-chun;Yeon, Seong-chan
    • Journal of Veterinary Clinics
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    • v.32 no.3
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    • pp.278-281
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    • 2015
  • An 8-year-old male red fox (Vulpes vulpes) in Species Restoration Technology Institute of Korea National Park Service (KNPS), revealed nodular growths in its ventro-cervical region. The fox was introduced from Young-Yang Gun in 2012 to KNPS for re-introduction of the red fox. It has been cared in captive facility and showed the mass in August 2013 that was sent to Wildlife Medical Center. For the diagnosis of underlying disease and cervical mass, radiographical and sonographical examinations, complete blood count, serum chemistry analysis, peripheral blood smear examination and surgical removal of the mass were performed. The mass was fixed in 10% neutral buffered formalin and processed routinely for haematoxylin and eosin (HE) stain. Based on hematological and serum chemical examination, the fox showed mild leukocytosis, thrombopenia, increase of creatine kinase MB (CKMB) and uric acid. However, it was considered as no clinical relevance since the fox showed no related clinical signs. Macroscopically, the mass was round shape, whitish and well-demarcated. Microscopically, it was diagnosed as a lipoma consisting of mature adipose tissue. Lipoma is a common benign tumor in most domestic animals, however it has never been reported in the red fox. The present case report provides comprehensive diagnosis of a subcutaneous lipoma in a red fox.

Initial Behavior and Shrinkage Properties of Lime Mortars for Restoration of Cultural Heritage According to the Mixing Ratio (석회 종류와 배합비 별 문화재 보수용 석회 모르타르의 초기거동특성과 수축특성 연구)

  • Nam, Byeong Jik;Noh, Sang Kyun;Kim, Eun Kyung;Ahn, Sun Ah;Kang, So Yeong
    • Journal of Conservation Science
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    • v.36 no.6
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    • pp.456-474
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    • 2020
  • This study investigated the initial behavior (flowability and setting properties) and shrinkage characteristics of lime mortar, based on the mixing ratio of hydrated lime (lump, powder) and commercial lime, which is primarily used for repairing and restoring cultural assets. The flowability showed that the optimum mixing water contents of the masonry lime mortar were 8-10% for the lump hydrated lime, 10-18% for the powdered hydrated lime, and 17-40% for the commercial hydrated lime. The results of the setting and shrinkage analysis showed that the average final setting time ratio compared to the standard of cultural asset repair was in the increasing order of commercial hydrated lime(0.4) < powder hydrated lime(5.6) < lump hydrated lime(5.7). Moreover, the average shrinkage ratio was ordered as lump hydrated lime(1.1) < powder hydrated lime(1.2) < commercial hydrated lime(3.0). The analysis of the physical and chemical characteristics of hydrated lime showed that the optimum mixing water content was reduced as the particle size of the lime increased, thus delaying the setting time and decreasing the length change rate (shrinkage). These results are expected to contribute to the prediction of the initial behavior and shrinkage characteristics of mortars using handmade and commercial lime during repair and restoration work on cultural, heritage buildings.

Priority Determination of the Projects for Ecological Restoration of the Stream : Case Study for Han River Estuary (생태하천 복원사업 우선순위 선정에 대한 연구: 한강하구를 중심으로)

  • Seonuk Baek;Junhak Lee;Seungmin Lee;Haneul Lee;Hung Soo Kim;Soojun Kim
    • Journal of Wetlands Research
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    • v.25 no.1
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    • pp.64-73
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    • 2023
  • Before 2022, there was a lot of confusion in the process of planning and implementing the projects for ecological restoration of the stream due to dualization the principal agent of stream management. Because the Ministry of Environment took charge of the project in 2022, securing the health of aquatic ecosystem of stream became an essential factor in the project. Therefore, in this study, the streams that require the project for ecological restoration was selected in Han River estuary, where it is essential to secure the health of the stream aquatic ecosystem as blackish water zone and Ramsar wetland are located. Physical, chemical, spatial/humanistic, health of aquatic ecosystems evaluation indexes were calculated based on the detailed facts and figures of the project for ecological restoration of the stream in the beginning. Ranking, re-scaling, z-score, and t-score normalization methods were applied to the calculated evaluation index, and the values were compared and analyzed. After that, the entropy weight method was applied to each evaluation index. Through this process, the streams(Mokgamcheon, Anyangcheon etc.) that require the project for ecological restoration were selected for the purpose of securing the health of the aquatic ecosystem in Han River estuary. The result of this study can be used as basic research data in the process of selecting the priority determination of the projects for ecological restoration of the stream.

Characterization of Membrane Fouling and It's Optimal Chemical Cleaning Method in MF Process using D dam water (D댐수를 이용한 정밀여과 공정에서 막오염 특성 및 최적 화학세정방법 조사)

  • Kim, Chung H.;Lim, Jae L.;Lee, Byung G.;Chae, Seon H.;Park, Min G.;Park, Sang H.
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.559-569
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    • 2007
  • The purposes of this study were to find the main foulant of membrane and the optimal chemical cleaning method for MF(microfiltration) drinking water treatment system using D dam water as water source. The MF pilot plant which can treat maximum $500m^3/d$ consisted of 3 racks and was operated for 10 months under various operation conditions. After 10 months operation, $1^{st}$ and $2^{nd}$ rack of membrane pilot plant system were cleaned chemically and the degree of the restoration of the fouled membrane in terms of the pure water flux was detemnined. Inorganic compounds which contained in chemical cleaning waste was analyzed by Inductively Coupled Plasma (ICP). One membrane module for 3rd rack was disjointed and membrane fouling materials, especially inorganic compounds were investigated by Electron Probe Microanlysis (EPMA) to elucidate the reason of TMP increase. And also, the various chemical reagents (1N HCl or $H_2SO_4$, oxalic acid as acid and 0.3% NaOCl as alkali) were tested by combination of acid and alkali to determine the optimal chemical cleaning method for the MF system using micro-modules manufactured using the disjointed module. It was verified that the inside and outside of membrane module was colorized with black. As a result of the quantitative and semi-qualitative analysis of membrane foulant by ICP, most of inorganic foulant was manganese which is hard to remove by inorganic acid such as HCI. Especially, it was observed by EPMA that Mn was attached more seriously in inside surface of membrane than in outside surface of that. It was supposed that Mn fouling in inside surface of membrane might be caused by the oxidation of soluble manganese (Mn(II)) to insoluble manganese ($MnO_2$) by chlorine containing in backwashing water. The optimal cleaning method for the removal of manganese fouling was consecutive cleaning with the mixture of 1N HCl and 1% of oxalic acid, 0.3% NaOCl, and 1N HCl showing 91% of the restoration of the fouled membrane.

Study on Degradation Characteristics and Chemical Cleaning Methods of Plasticized PVC for Conservation of Plastic Artifact (연질 PVC 작품 보존을 위한 가소제 종류별 열화 특성 및 화학적 세척법 연구)

  • Lee, Na Ra;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.35 no.2
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    • pp.159-168
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    • 2019
  • Plasticizers, which are added to plastics, can cause exudation, which means that the plasticizer comes out from surface of the plastics. This causes the surface of plastic artworks to become sticky, and this allows dust and pollutants to become attached to the surface. Therefore, in this study, the degradation characteristics and chemical cleaning methods of each type of plasticizer are evaluated using PVC specimens. To evaluate the degradation characteristics and chemical cleaning methods, microscopic observation, chromaticity and weight measurement, and FT-IR spectroscopy were performed. The results showed that PVCs containing different plasticizers have different degradation patterns. Especially, the PVC containing TOTM showed discoloration and exudation. In the evaluation of the chemical cleaning methods, ethyl alcohol and KOH solution showed good effects, but their stability was not good. Surfactant was found to have a good cleaning effect and stability as a cleaner for exudated plasticizers.

Graphene Oxide-based Direct Measurement of DNase I Activity with Single Stranded DNA

  • Gang, Jongback
    • Bulletin of the Korean Chemical Society
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    • v.35 no.9
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    • pp.2749-2752
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    • 2014
  • Recent studies have shown that single-stranded DNA adsorbed onto graphene oxide is protected from DNase I cleavage. However, double-stranded DNA bound to graphene oxide and could be digested by DNase I. To elucidate whether single-stranded DNA is protect from DNase I in the presence of graphene oxide, this study conducted DNase I digestion using single-stranded DNA and single-stranded DNA containing the duplex region in the presence of graphene oxide. Addition of DNase I resulted in restoration of the fluorescence emission that had been quenched when DNA was adsorbed to graphene oxide. It indicates that DNase I cleaved the adsorbed single-stranded DNA onto graphene oxide, which was sufficient for the detection of DNase I activity.