• Clean Technology
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• v.19 no.4
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• pp.416-422
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• 2013

In environmental friendly aspects, the synthesis of glycerol carbonate from glycerol using carbon monoxide and oxygen gases which were produced in petrochemical plants was studied. The oxidative carbonylation of glycerol under batch reaction system was performed on parameter conditions such as effect of various metals (Cu, Pd, Fe, Sn, Zn, Cr), oxidizing agents, mole ratio of carbon monoxide to oxygen, catalyst amount, solvent types, reaction temperature and time and dehydrating agents. In particular copper chloride catalysts showed the excellent activities, and the glycerol carbonate yields over CuCl and $CuCl_2$ catalysts were the maximum of 44% and 64%, respectively at the following reaction conditions: solvent as nitrobenzene, mole ratio of 1:3:0.15 (glycerol:carbon monoxide:catalyst), mole ratio of 2:1 (carbon monoxide:oxygen), the total pressure of 30 bar at 413 K for 4 hr. It was found that reactivity were significantly different depending on the oxidation number of Cu catalysts, and oxygen plays an important role as oxidizing agents in producing H2O during oxidation reaction after carbonylation of glycerol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.15-21
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• 1986

This study was conducted to research the industrial utilizaion of the maize germs separated in the manufacture of the cornstarch. The maize germs contained crude protein (25.3%) and crude fat (19.2%), with the 512 Kcal/100g of determined food energy values. It was found to have the valuable amounts of essential minerals, such as the content of calcium and phosphorus were low (53.0, 12.3mg%), while those of potassium (495.4mg%), magnesium (95.0mg%), zinc (48.3ppm) and manganese (45.2ppm) were plentiful. It was noted that the iodine value was 44.0, saponification value 292.3, acid value 1.5 and peroxide value about 3.3. The lipid fractions obtained by silicic acid column chromatography were mainly composed of neutral lipid, whereas, the contents of glycolipid and phospholipid were scarcely. The major fatty acids in total lipids were linoleic $(60{\sim}62.5%)$, oleic $(20{\sim}22.5%)$ and palmitic $(10{\sim}13.5%)$ acids. The content of the unsaturated fatty acids was more predominant than that of the saturated fatty acids. The content of the insoluble proteinous nitrogen (32.5%) was the most abundant. whereas, the contents of soluble proteinous nitrogen (12.7%) and peptide proteinous nitrogen (3.3%) were low. The major amino acids of the maized germs were glutamic, glycine, alanine and aspartic. It has been identified by the SDS-disc electrophoresis that the protein of maized germs had $5{\sim}6$ bands. Compared with standard substances, the molecular weight of the main protein was estimated to be $14,500{\sim}24,500$.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.568-574
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• 2013

A semi-pilot biofilter packed with media with immobilized Thiobacillus sp. IW and return sludge, was operated under various operating conditions in order to treat malodorous waste air containing both hydrogen sulfide and ammonia which are major air pollutants emitted from composting factories and many publicly owned treatment works (POTW). At the incipient and middle stages of a semi-pilot biofilter operation, the hydrogen sulfide-removal efficiency behaves regardless of an inlet-load of ammonia. However, the ammonia-removal efficiency decreased as an inlet-load of hydrogen sulfide increased. Nevertheless, at the final stage of the semi-pilot biofilter operation, the ammonia-removal efficiency was not affected by the increase of hydrogen sulfide-inlet load. It is attributed to that a serious acidification of semi-pilot biofilter-media did not occur due to continuous injection of buffer solution at the final stage of the semi-pilot biofilter operation. When both hydrogen sulfide and ammonia contained in malodorous waste air were treated simultaneously by semi-pilot biofilter, the maximum elimination capacities of hydrogen sulfide and ammonia turned out to be ca. 58 and $30g/m^3/h$, respectively. These maximum elimination capacities were estimated to be ca. 39 and 46% less than those for lab-scaled biofilter-separate elimination of hydrogen sulfide and ammonia, respectively. Thus, for the simultaneous biofilter-treatment of hydrogen sulfide and ammonia, the maximum elimination capacity of ammonia decreased by 7% more than that of hydrogen sulfide.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1158-1163
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• 2006

Bisphenol A (BPA), 2,2-bis(4-hydroxyphenyl) propane, has been widely used as a monomer for production of epoxy resins and polycarbonate plastics, and final products of BPA include adhesives, protective coatings, paints, optical lens, building materials, compact disks and other electrical parts. Since BPA is a toxic chemical to elicit acute cell cytotoxicity and chronic endocrine disrupting activity, the degradation of BPA has been focused during last decades. To overcome the problem of photo-, and chemical-degradation of BPA, in this study, a bacterium that is able to biodegrade BPA, was isolated. The bacterium, isolated froln the soil of plastic factory, was identified as Acinetobacter calcoaceticus (strain BP-2) based on physiological and 16S rDNA sequencing analysis. A. calcoaceticus BP-2 was able to grow in the presence of $1140{\mu}g\;ml^{-1}$ BPA. Biodegradation experiments showed that BP-2 mineralized BPA via 4-hydroxybenzoic acid and 4-hydroxyacetophenone, and average degradation rate was $53.3{\mu}g\;ml^{-1}\;day^{-1}$ under optimal conditions (pH 7 and $30^{\circ}C$). In high density resting cell $(3.5g-dcw.1^{-1})$ experiments, the maximal degradation rate was increased to $89.7{\mu}g\;ml^{-1}\;h^{-1}$. Our results suggest that BP-2 has high potential as a catalyst for practical BPA bioremediation.

• Journal of Life Science
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• v.20 no.5
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• pp.639-643
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• 2010

Sudden deaths have occurred in feedlot cattle with marked necro-hemorrhagic enteritis of the jejunum, ileum and colon. Suckling beef calves are the most frequently affected. Over-consumption of large amounts of milk, inadequate colostrum intake, chilling and stress are conducive to the development of enterotoxemia. Enterotoxemia caused by Clostridium perfringens type D mostly occurs following a sudden change of diet, particularly to feeds made richer in order to grow the cattle to market weight in feedlots. During July 2006, sudden deaths of cattle occurred in the Youngcheon regional area of Gyeongbuk province. There were no significant clinical signs except anorexia, depression, intermittent diarrhea and mild respiratory failure. Histological findings revealed a prominent intranuclear inclusion as well as infiltration of the globular leukocytes in various organs including the heart, kidneys, liver, spleen and lymph nodes. Spleen and lymphatic tissues showed lymphatic necrosis and a starry sky appearance. In the submucosa of the small intestines, basophilic aggregation was detected with massive infiltration of the globular leukocytes and eosinophils. Gram staining for the tissue sections containing inclusions of the small intestines revealed a positive histochemical reaction. Taken together, we suggest that Clostridium perfringens type D-induced enterotoxemia is determined to be the cause of sudden death of feedlot cattle.

• Journal of the Korean Institute of Gas
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• v.3 no.1
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• pp.48-57
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• 1999

Safe plants are maintained by the systematic identification of potential hazards. Various hazard evaluation methods have been developed in pursuit of safe plants. Recently, much efforts has been made for the automation of hazard evaluation system by introducing expert system to get rid of weak points of the conventional hazard evaluation methods. HAZOP study is recognized as one of the most systematic and logical hazard evaluation methods. However, it has several disadvantages; experts should participate simultaneously, the detailed study is time-consuming, and the quality of the results largely depends on the quality of the experts. Therefore, the automation of HAZOP Study is highly beneficial for reducing the required time and obtaining the consistent evaluation results. In this study, a framework for the automation of HAZOP study is suggested. Based on the suggested framework, HAxSYM, an expert system to automate HAZOP study, has been developed. The case study validates the performance of the developed system, and the results are compared with the results from the conventional HAZOP study.

• Journal of the Institute of Convergence Signal Processing
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• v.20 no.1
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• pp.16-23
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• 2019

Fine particulate matter known as PM 2.5 refers to the atmospheric particulate matter that has a diameter less than 2.5 micrometer identified as dangerous element for human health and its concentration can provide us a clear picture about air dust concentration. Humans stay indoor almost 90% of their life time and also there is no official indoor dust concentration data, so our study is focused on measuring the indoor air quality. Indoor dust data monitoring is very important in hospital environments beside that other places can also be considered for monitoring like classrooms, cements factories, computer server rooms, petrochemical storage etc. In this paper, visible light communication system is proposed by Manchester encoding technique for electromagnetic interference (EMI)-free indoor dust monitoring. Important indoor environment information like dust concentration is transferred by visible light channel in wide range. An average voltage-tracking technique is utilized for robust light detection to eliminate ambient light and low-frequency noise. The incoming light is recognized by a photo diode and are simultaneously processed by a receiver micro-controller. We can monitor indoor air quality in real-time and can take necessary action according to the result.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.324-326
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• 2004

20세기 말까지만 해도 경제발전은 자원고갈과 자연환경파괴를 통한 대량생산 및 대량소비를 전제로 하여 이루어 졌다고 평가할 수 있다. 그 결과 세계의 자연환경은 급속히 훼손되었으며, 환경오염은 이제 인류의 생존을 위협하는 단계에 이르렀다. 이 같은 위기상황에 대처하기 위하여 지난 1980년대부터 선진국을 중심으로 환경경영에 대한 인식이 확산되기 시작하였다. 무엇보다도 자연환경 의 보존을 요구하는 사회적 압력은 기업으로 하여금 환경경영 의 필요성을 깨닫게 하였다. 환경 경영이란 기업들이 새로운 비교 우위를 창출하기 위하여 경 영 방식의 혁신에 있어서 자연환경을 초점으로 삼는 것이다. 환경경영이란 환경보전을 요구하는 이해 관계자들로부터의 요구에 기업이 이에 적극적으로 대응함으로써 한경보호와 경영성과를 동시에 달성하는 종합적인 경영을 의미한다. 환경경영은 이업의 전 활동에 걸친 전사적인 전략적 차원의 활동으로 기업경영이 어느 한 기능분야에 국한된 개념이 아니다. 궁극적으로 환경보호와 성장의 조화라는 기업의 목표달성을 위해 기업의 생산, 재무, 인사조직, 마케팅, 회계정보시스템등의 활동이 모두 통합되어야 할 것이다. (김종대, 이의훈:2003) 최근 들어 환경경영이 기업의 가치에 미치는 영향에 대한 연구가 활발히 전개되고 있는 가운데 선진국의 경우 기업의 가치가 대체적으로 정확하게 주가에 반영되고 있는 가운데 선진국의 경우 기업의 가치가 대체적으로 정확하게 주가에 반영되고 있어 우리기업들이게 시사하는 바가 크다 하겠다. 환경경영과 기업가치와의 상관관계를 조사한 연구결과에 따르면 우수한 환경경영을 실천하고 있는 기업의 주식을 중심으로 포트폴리오를 구성한 펀드의 수익율이 상대적으로 높게 나타나고 있어 환경경영의 중요성을 뒷받침하고 있다. 이를 위하여 본 논문은 우선적으로 기업의 환경경영에 기본이 되는 중요한 환경경제 유인정 책과 규제들을 중심으로 살펴보고자 하였다.학적 합성이 아주 까다로운 약제물질 등을 천연상태에서 합성하고 있기 때문이다. 또 식물은 lipoxygenase 효소계가 있어서 마치 천연물 석유제조공장과 같은 제조공정 capacity를 가지고 있다. 그러면 식물/식품 GMO는 안전한 것인가? 아니, KBS의 한 사회자가 말했듯이, 그리고 많은 소비자들이 믿는 것처럼 GMO는 위험한가? GMO에 대한 일반 사람들의 공포감은 Green Peace 당원들뿐만 아니라 일부 과학자들에 의해서도 조장되고 있다. 이러한 분위기 속에서 GMO에 의한 제2 녹색혁명은 Africa 대륙에서의 제1 녹색혁명이 지금도 지연되는 것과 같다고도 볼 수 있다. GMO의 환경에 대한 악영향은 과대 선전되어있는 것이 아닌가? 마치 GMO가 화학비료, 농약제보다 더 위험하다고 믿는 사람들도 많다. 나는 이러한 GMO 공포증이 과학적으로 그리고 "Risk Assessment"의 견지에서 볼 때 그 근거가 희박하다고 보여주는 몇 몇 실험 및 경험 사실들을 인용하려 한다. 그리고 올바른 Risk Assessment야 말로 한국의 21세기 BT 산업을 경쟁력 있게 하고 국민 년 소득 2만불 달성에 중요한 기여를 하게 될 것이라고 생각한다. 한국은 농토가 적고 천연자원이 빈약하다. GMO는 21세기의 생존 경쟁 산업이다. 제2의 녹색혁명은 얼마든지 가능하며, 한국은 부족한 농토와 빈약한 자원에도 불구하고 능력 있는 인적자원이 풍부하여 GMO 개발 연구에 국제적 경쟁력을 키울 수 있다. 그러나 GMO에 대한 논쟁만 하고 있으면 이미 때가 늦는다. 미국은 이미 GMO-BT 시장을 거의 완전 독점했으며, 타국에서의 논쟁과 불합리적으로 엄격한 GMO 관련 규정을 조장하고 환영한다.이상의 결과와 같이 인삼 saponin 성분들은 arachidonic acid로부터 cyclooxygenase를 통해 일단 생성된 endoperoxide에서 각각의 prostagland

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.48-52
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• 2008

According to extremely industrial growth, gas facilities, equipments and chemical plants are gradually increased due to incremental demands of annual amount of gases. The safety management of gases, however, is still far from their requirements. Methane, the principal ingredient of natural gas, is inflammable and explosive and is much used in factories and houses. Therefore, these gas safety management is essential. So, we, with a program of the gas safety management, hope to develop the detection system of methane gas leak using mid-infrared ray LED and PD with $3.2\;{\mu}m$. The cryogenic cooling device is indispensible at laser but needless at LED driven on the room temperature if manufacturing optical sensor with $3.2\;{\mu}m$. It, consequently, is not only possible to implement for subminiature and portable type but also able to speedily detect methane of extremely small quantities because the $CH_4$ absorption intensity at $3.2\;{\mu}m$ is stronger than that at $1.67\;{\mu}m$. Our objective of research is to prevent gas leak accidents from occurring previously and to minimize the extent of damage from them.

• Journal of the Mineralogical Society of Korea
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• v.18 no.1
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• pp.11-17
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• 2005

Na-A zeolite were synthesized from melting slag of the incinerated ash by the alkaline activation processes. The experiments were performed in stainless steel vessels, with continuous stirring during the reaction periods. The silica-rich solution, a starting material, which was the waste of crystal growth factory, contains 5.7 wt% SiO₂ and 3.2 wt% Na₂O. And NaAlO₂ was made by the reaction of aluminium dross and NaOH solution and its molar ratios were Na₂O/Al₂O₃= 1.2 and H₂O/Na₂O=9. During the residence time of 7∼8 h at 80℃, the mixing of the silica-rich solution, NaAlO₂ and melting slag yields the production of homogeneous Na-A zeolite. The optimal reactant composition in molar ratio of Na₂O:Al₂O₃:SiO₂ was 1.3∼l.4 : 0.8∼0.9 : 2 and mixing ratio of solution and slag was 1/7∼10 (g/cc). Synthesized Na-A zeolite has cubic form uniformly and its size ranges about 1 ㎛. Ca/sup 2+/ ion exchange capacity of the Na-A was about 180∼210 meq/100g, corresponding approximately 80% to the commercial detergent builder.