• 한국가스학회지
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• 제19권4호
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• pp.15-21
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• 2015

최근 발생한 크고 작은 화재 폭발 누출 사고들을 살펴보면, 하청업체의 근로자들이 원청업체 사업장에서 유해 위험한 정비 보수작업 중에 재해를 당하는 사고가 증가하고 있다. 따라서 본 연구에서는 공정안전보고서 제출대상 사업장을 대상으로, 설문조사를 통해 도급업체의 안전관리 실태를 파악하고, 도급업체의 안전관리 향상을 위해 공정안전관리를 활용한 원청업체와 하청업체간의 책임과 합리적 역할분담, 안전 보건정보 제공, 정비 보수작업 시 근로자 보호 방안을 제안하였다. 본 연구결과는 유해 위험작업 시 하청업체의 안전관리 강화와 개선에 도움을 주고, 원청업체와 하청업체간의 상생 협력관계를 구축하여 산업재해를 감소시키는데 활용될 수 있을 것으로 기대된다.

• Journal of Animal Science and Technology
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• 제52권6호
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• pp.513-519
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• 2010

A series of experiments were performed to study the influence of the following parameters on the physical traits and composition of swine manure compost: (1) addition of magnesium (Mg) at a molar ratio of 1.2 with respect to $PO_4$, and (2) reutilization of compost containing $MgNH_4PO_4{\cdot}6H_2O$ (magnesium ammonium phosphate, MAP). Three independent batch tests were conducted for replication: batch test I-control (C) and Mg added (T), batch test II-C, T and compost recycle ($T_{R1}$), and batch test III-C, T and compost recycle ($T_{R2}$). Magnesium addition and compost reutilization had no adverse effect on the degradation of organic matter. Reuse of the compost, however, had a clear effect on the total nitrogen (TN) and total phosphorus (TP) contents in the final compost. Repeated compost reutilization as a bulking material was resulted in composts rich in N and P. Upon adding the Mg supplement to the composting materials, the ortho-phosphate (OP) to TP ratio decreased due to the MAP crystallization reaction. The decrease in the OP/TP ratio and the increase in the TP content of the compost indicate that water-soluble phosphate is converted into a slow-release phosphate by the formation of crystals during composting. X-ray diffraction analysis of the irregular shaped crystals in the compost indicated that they are MAP crystals and that the crystallization of MAP begins immediately after the addition of the Mg supplement. The Mg addition to composting materials and the reutilization of compost as a bulking material would be a practical means to conserve nutrient content.

• 한국가스학회지
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• 제18권5호
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• pp.33-39
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• 2014

열매체유는 화학플랜트의 가열시스템, 열교환시스템, 특정한 가스공정, 사출성형 시스템 및 펄프 제지공정에 사용되고 있다. 열매체유는 열적 산화 분해에 잘 견디며 안전성이 뛰어나며, 열매체유가 누출이나 분출의 경우에는 점화원이 있을때 쉽게 점화된다. 본 연구에서는 공정안전관리 사업장의 화재 폭발 사고를 예방하기 위해서 열매체유의 사용 실태조사를 통해 안전관리 상태를 고찰하였다. 사업장의 공정시스템에서 사용된 열매체유의 사용실태는 개발된 설문지에 의해서 조사되었다. 본 연구 결과는 열매체유의 관리나, 열매체유 공정의 안전한 운전과 유지와 관련된 화재 폭발 사고 예방을 위한 안전관리 대책 수립에 활용될 수 있을 것이다.

• 폴리머
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• 제37권6호
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• pp.802-808
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• 2013

알로인이 첨가된 하이드로젤을 제조하여 창상치유의 효과를 관찰하였다. Poly(vinyl alcohol)(PVA)과 carboxyl methyl cellulose(CMC)를 동결-융해 방법으로 결합시킨 하이드로젤을 제조하였다. 젤의 특성과 약물의 방출, in vivo 창상치유 실험 및 병리학적 평가를 진행하였다. 쥐 등에 만든 상처의 치유 실험은 알로인이 첨가된 PVA/CMC(5:5) 하이드로젤 그룹과 대조군 그룹의 알로인이 함유된 카보머934 젤 혹은 순수 카보머934 젤로 처치한 그룹보다 CMC의 수분과 알로인의 피토케미칼 활성 때문에 빠른 치유력을 확인할 수 있었다. 결론적으로 알로인이 첨가된 창상용 드레싱으로 5% PVA, 5% CMC 그리고 0.125% 알로인의 조성은 상처치료에 효과적이며 창상용 드레싱으로 활용을 기대할 수 있다.

• 생약학회지
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• 제41권3호
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• pp.166-173
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• 2010

Oxidative stress to proteins, lipids, or DNA is higher in human autopsy tissue and in rodent models of a number of neurodegenerative conditions, including Alzheimer's and Parkinson's disease. On the basis of this information, we established a screening system using N18-RE-105 cells to identify therapeutic agents that can protect cells from glutamate toxicity. During the course of our screening program, we recently isolated the active compound 9-hydroxy-$\alpha$-tocopherone ($\alpha$-TP), which prevents glutamate-induced cell death, from Viola mandshurica. The chemical structure of $\alpha$-TP was identified using spectroscopic methods and by comparison with literature values. Antioxidant activity and protective effects of $\alpha$-TP were evaluated by DPPH radical-scavenging assay, morphological assay, MTT reduction assay, and lactate dehydrogenase (LDH) release assay. These results suggest that $\alpha$-TP could be a new potential chemotherapeutic agent against neuronal diseases.

• 방사선산업학회지
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• 제9권4호
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• pp.199-207
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• 2015

Typical radiation cross-linked hydrogels has the characteristic that high water content, but low emission efficiency of active ingredients. Therefore, the hydrogel was prepared by the addition to collagen, which is closely related to the formation of skin wrinkles in biocompatibility and highly water-soluble carboxymethyl cellulose sodium salt (CMC) in order to preparation of hydrogels has excellent emission efficiency of active ingredients. Hydrogels were prepared by dissolving CMC and collagen each of 0.5%, 10% concentration in deionized water. Then, prepared hydrogels are performed by gamma-radiation at 1, 3, 5 kGy irradiation dose. The results showed that the gel fraction of after irradiated 3 kGy hydrogel was higher than before irradiated gelation as long as the 55.3%. The swelling rate of irradiated 3 kGy hydrogel was lower than the non-irradiated sample. The compressive strength of 3 kGy irradiated hydrogel was the highest. The visco-elastic did not show any significant differences, even after irradiation. The CMC hydrogel in this study suggested a potential use as a material for the mask pack for improved emission efficiency of the active ingredient and anti-wrinkles.

• 융합정보논문지
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• 제9권11호
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• pp.254-258
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• 2019

건강하고 아름다운 모발을 보호하기 위해 펌 제에 알로에 추출물을 첨가해 모발보호 효과를 알아보고자 한다. 처치 군은 그룹 II(파마 약만 사용한 그룹), 그룹 III(알로에 추출물을 1제에만 첨가), 그룹 IV(알로에 추출물을 2제에만 첨가), 그룹 V(알로에 추출물을 1제와 2제에 첨가)로 나누어 진다. 실험 모발은 1년간 영구 염색 등 화학치료를 받지 않은 20대, 30대, 40대 여성의 모발에서 채취해 100% 알로에 추출용액을 사용한다. 머리카락 굵기와 큐티클, 인장강도, 신장 및 연신율을 측정하기 위해 실험 환경은 28.9도, 습도는 72%로 유지했다. 모든 통계 시험은 5% 유의수준에서 수행되었다. 큐티클, 연신율, 형성률이 현저히 향상되었고(P<.05) 큐티클은 그룹 V에서, 연신율은 그룹 III에서 가장 좋았다. 결론적으로 파마 치료에 첨가된 알로에는 큐티클, 신장률, 모발 형성에 효과적이었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권2호
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• pp.23-29
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• 2018

This study explored secondary effects of the residual hydrofluoric acid (HF) after a hypothetical acid spill accident by investigating the long-term dissolution of minerals and leaching of pre-existing arsenic (As) from two soil samples (i.e., KBS and KBM) through batch and column experiments. An increase in the HF concentration in both soil samples resulted in a dramatic increase in the release of major cations, especially Si. However, the amounts of mineral dissolved were dependent on the soil type and mineral characteristics. Compared to the KBM soil, relatively more Ca, Mg and Si were dissolved from the KBS soil. The column experiment showed that the long-term dissolution rates of the minerals are closely associated with the acid buffering capacity of the two soils. The KBM soil had relatively higher effluent pH values compared to the KBS soil. Also, more As was leached from the KBM soil, with a more amorphous hydrous oxide-bound As fraction. These results suggest that the potential of heavy metal leaching by the residual acid after an acid spill will be influenced by heavy metal speciation and mineral structure in the affected soil.

• International Neurourology Journal
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• 제22권4호
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• pp.246-251
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• 2018

Purpose: To determine whether responses to serotonin are altered in bladder strips from cats diagnosed with a naturally occurring form of bladder pain syndrome/interstitial cystitis termed feline interstitial cystitis (FIC). Methods: Full thickness bladder strips were isolated from aged matched healthy control cats and cats with clinically verified FIC. Bladder strips were mounted in an organ bath and connected to a tension transducer to record contractile activity. A serotonin dose response ($0.01-10{\mu}M$) was determined for each strip with the mucosa intact or denuded. Results: Bladder strips from control and FIC cats contracted in response to serotonin in a dose-dependent manner. The normalized force of serotonin-evoked contractions was significantly greater in bladder strips from cats with FIC (n=7) than from control cats (n=4). Removal of the mucosa significantly decreased serotonin-mediated responses in both control and FIC bladder preparations. Furthermore, the contractions in response to serotonin were abolished by $1{\mu}M$ atropine in both control and FIC bladder strips. Conclusions: The effect of serotonin on contractile force, but not sensitivity, was potentiated in bladder strips from cats with FIC, and was dependent upon the presence of the mucosa in control and FIC groups. As atropine inhibited these effects of serotonin, we hypothesize that, serotonin enhances acetylcholine release from the mucosa of FIC cat bladder strips, which could account for the increased force generated. In summary, FIC augments the responsiveness of bladder to serotonin, which may contribute to the symptoms associated with this chronic condition.

• Tribology and Lubricants
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• 제34권6호
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• pp.292-299
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• 2018

The objective of this research is to investigate the impact of engine oil aging on PM(Particulate Matter), exhaust gases, and DPF. It is widely known that the specification of a lubricant and its consumption in an ICE considerably influences the release of regulated harmful emissions under normal engine operating conditions. Considering DPF clogging phenomena associated with lubricant-derived soot/ash components, a simulated aging mode is designed for DPF to facilitate engine dynamometer testing. A PM/ash accumulation cycle is developed by considering real-world engine operating conditions for the increment of engine oil consumption and natural DPF regeneration for ash accumulation. The test duration for DPF aging is approximately 300 h with high- and low-SAPs engine oils. Detailed engine lubricant properties of new and aged oils are analyzed to evaluate the effect of engine oil degradation on vehicle mileage. Furthermore, physical and chemical analyses are performed using X-CT, ICP, and TGA/DSC to quantify the engine oil contribution on the PM composition. This is achieved by sampling with various filters using specially designed PM sampling equipment. Using high SAPs engine oil causes more PM/ash accumulation compared with low SAPs engine oils and this could accelerate fouling of the EGR in the engine, which results in an increase in harmful exhaust gas emissions. These test results on engine lubricants under operating conditions will assist in the establishment of regulated and unregulated toxic emissions policies and lubricant quality standards.