• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.654-660
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• 1998

$[Fe^{II}Fe^{III}BPLMP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amino) methyl]-4-methylphenol (HBPLMP). Complex I has been characterized by X-ray diffraction method as having (μ-phenoxo)bis(acetato)diiron core. Complex 1 was crystallized in the monoclinic space group C2/c with the following cell parameters: a=41.620(6) Å, b=14.020(3) Å, c=27.007(4) Å, β=90.60(2)°, and Z=8. The iron centers in the complex 1 are ordered as indicated by the difference in the Fe-O bond lengths which match well with typical $Fe^{III}-O\; and\; Fe^{II}-O$ bond lengths. Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electochemical methods. Complex 1 exhibits strong bands at 592 nm, 1380 nm in $CH_3CN$ (ε = 1.0 × 103 , 3.0 × 102). These are assigned to $phenolate-to-Fe^{III}$ and intervalence charge-transfer transitions, respectively. Its NMR spectrum exhibits sharp isotropically shifted resonances, which number half of those expected for a valence-trapped species, indicating that electron transfer between $Fe^{II}\;and\;Fe^{III}$ centers is faster than NMR time scale. This complex undergoes quasireversible one-electron redox processes. The $Fe^{III}_2/Fe^{II}Fe^{III}\;and\;Fe^{II}Fe^{III}/Fe^{II}_2$ redox couples are at 0.655 and -0.085 V vs SCE, respectively. It has $K_{comp}=3.3{\times}10^{12}$ representing that BPLMP/bis(acetate) ligand combination stabilizes a mixed-valence $Fe^{II}Fe^{III}$ complex in the air. Complex 1 exhibits a broad EPR signal centered near g=1.55 which is a characteristic feature of the antiferromagnetically coupled high-spin $Fe^{II}Fe^{III}$ system $(S_{total}=1/2)$. This is consistent with the magnetic susceptibility study showing the weak antiferromagnetic coupling $(J= - 4.6\;cm^{-1},\; H= - 2JS_1{\cdot}S2)$ between $Fe^{II}\; and \;Fe^{III}$center.

• Corrosion Science and Technology
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• v.17 no.6
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• pp.279-286
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• 2018

Austenitic stainless steels used in nuclear power plants mainly use pipes made of seamless pipes, which depend on imports. The manufacturing process and high cost are some of the problems associated with seamless pipes. Therefore, in this study, the corrosion characteristics of the seamless pipe and the SAW pipe were assessed to determine the safety and reliability of the SAW pipe in a bid to replace the seamless pipe. Microstructure was analyzed using an optical microscope and the degree of hardness was measured using a Rockwell B scale. Intergranular corrosion resistance was evaluated by ASTM A262 Practice A, C, and E methods. The degree of sensitization was determined using a DL-EPR test. Anodic polarization test was performed in deaerated 1% NaCl solution at $30^{\circ}C$ and the U-bend method was used to evaluate the SCC resistance in 0.01 M $Na_2S_4O_6$ at $340^{\circ}C$ and 40% NaOH solution at $290^{\circ}C$. Weld metal of the SAW pipe specimen showed relatively high degree of sensitization and intergranular corrosion rate. However, annealing to SAW pipes improved the corrosion properties in comparison to that of the seamless pipe.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.36 no.3
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• pp.127-139
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• 2023

Objectives : The purpose of this study is to report a case of Ramsay-Hunt Syndrome showing continual improvement after 3 months of onset. Methods : This study was conducted with Ramsay-Hunt Syndrome patient who hospitalized in Ophthalmology, Otolaryngology & Dermatology Clinic of Korean medical hospital. The patient was treated with Korean medical treatment including Ligigeopoong-san Gagam, acupuncture, pharmacopuncture (Hwangryunhaedok-tang) and the other physics therapy. After treatment, we evaluated subjective symptoms, Yanagihara scale and H-B Grade. Results : As a result, the patient continued to improve even after 3 months after the onset, and showed complete recovery and significant improvement in subjective symptoms after treatment. Conclusions : It is considered that Korean medical treatment can be applied to the treatment of Ramsay-Hunt Syndrome.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.130-130
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• 2021

The increasing effect of urbanization has been more apparent through flooding and downstream water quality especially from heavy rainfalls. In response, stormwater runoff management solutions have focused on runoff volume reduction and treatment through infiltration. However, there are areas with low infiltration soils or are experiencing more dry days and even drought. In this study, a lab-scale infiltration system was used to compare the applicability of two types of soil as base layer in gravel-filled infiltration systems with emphasis on runoff capture and suspended solids removal. The two types of soils used were sandy soil representing a high infiltration system and clayey soil representing a low infiltration system. Findings showed that infiltration rates increased with the water depth above the gravel-soil interface indicating that the available depth for water storage affects this parameter. Runoff capture in the high infiltration system is more affected by rainfall depth and inflow rates as compared to that in the low infiltration system. Based on runoff capture and pollutant removal analysis, a media depth of at least 0.4 m for high infiltration systems and 1 m for low infiltration systems is required to capture and treat a 10-mm rainfall in Korea. A maximum infiltration rate of 200 mm/h was also found to be ideal to provide enough retention time for pollutant removal. Moreover, it was revealed that low infiltration systems are more susceptible to horizontal flows and that the length of the structure may be more critical that the depth in this condition.

• Journal of Practical Agriculture & Fisheries Research
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• v.17 no.1
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• pp.21-43
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• 2015

Korean floricultural industry has grown under the full backing of government, as it placed itself as the main export item since 2000s. Despite its high-speed growth after the domestic production scale of trillion won, the floricultural industry lost its pace after 2005, due to the market-opening of agricultural product and global economic depression. Although the national income is growing and the level of civilized living is following, spending on flowers is faltering. As of such circumstances, necessity for analyzing flower consumption trend and behavior has came out, along with the calls for expansion plan of flower consumption, under the basis of result analysis on consumer reports. The result of the research contains the trend/consumption behavior analysis on domestic and foreign flower industry to boost floricultural industry, along with reviews on various studies of the developmental process of domestic and foreign cut-flowers/pot-plants consumption trend. Also this study has reached to the various recognition of people toward flower, through a public survey. Through such results, this study would like to propose the measures for diffusion of flower-consumption culture, achieving the improvement of life-quality of public along. First, efforts on reviewing the customer accessibility is essential to create flower- culture and the consumption. Second, to eliminate the obstacles that prevents flowers from public's daily life is essential. Third is the effective public-relations on flowers. To create consuming culture and to adhere the positive images, it is essential to research and systematically organize categories of color, scent, and elements of flower and utilize them. Last proposal is the organization of flower-concerned personnels and the leading groups. The change is affected by the economical, social environment, along with the emotions of consumers. Therefore the necessity for the leading group to be the control-tower of such changes are very clear.

• Journal of Life Science
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• v.12 no.3
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• pp.242-249
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• 2002

The optimal culture conditions in 500$m\ell$ flask suture, 5$\ell$ jar fermenter and 2,000 $\ell$ large stale culture were investigated to maximize the production of antibiotic on Rhizoctonia solani AC4, the causal agent of vegetables damping-off, by the strain Bacillus ehimensis YJ-37. Starch (1.5%) as a carbon source, peptone (0.6%) as a nitrogen source and MgC1$_2$(0.15%) as a metal ion in the medium containing N $a_2$HP $O_4$(0.3%) showed the highest production of the antibiotic(s) in a rotary shake (200 rpm). Optimal initial pH of the culture medium, culture temperature and culture time for the antibiotic(s) production were pH 8.0, 32$^{\circ}C$ and 54hrs, respertively. Under the optimal renditions in flask culture, cell growth and antifungal activity (clear zone size) were 1.42 $\times$ 10$^{8}$ cfu/$m\ell$ (21g-DCW/ $\ell$) and 13.9 mm, respectively. In 5 $\ell$ jar fermenter (medium 3 $\ell$), optimal air flow, agitation speed and culture time for the antibiotic(s) production were 2 vvm, 200 rpm and 48hrs, respectively. Under the optimal conditions in 5 $\ell$ jar fermenter, tell growth and antifungal activity were 2.06 $\times$ 10$^{8}$ cfu/$m\ell$ (30g-DCW/ $\ell$) and 13.4 mm, respectively. Under the culture conditions of air flow (30 vvm) and agitation speed (200 rpm) at 32$^{\circ}C$ for 10 days in 2,000 $\ell$ large scale culture (medium 1,800 $\ell$, pH 8.0), cell growth and antifungal activity were 0.81$\times$10$^{8}$ cfu/$m\ell$ (12g-DCW/ $\ell$) and 8.6 mm, respectively.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.21-30
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• 2008

In this study, the antioxidant activities of 27 medicinal herbs and plants were measured. The dried medicinal herbs and plants were pulverized and extracted by water, 15% ethanol, and 45% ethanol, respectively at above $80^{circ}C$ for 90 minutes. The original and diluted extracts were tested for their antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity assay. Cornus officinalis (C) and Scutellaria baicalensis (S) were selected to develop rice wines with higher antioxidant activities, based on the result of the 45% ethanol extraction. The rice wine developed using sample showed the highest antioxidant activity as comparing to those of other commercial rice wines. The rice wine samples were analyzed for titratable acidity, pH, $^{\circ}Brix$, reducing sugar content, color (L, a, b), amino-acidity, and ultraviolet absorption. The preferences for color, aroma, and overall acceptability were determined using a 9-point hedonic scale by 150 consumers. The sweetness, sourness, fruitiness, color, and medicinal herb-taste levels of the developed rice wines were also evaluated, using a 9-point just-about-right scale. The mean overall acceptability score of c (5.54) was higher than that of sample S. Based on the results, the sourness and medicinal herb-taste levels of sample s should be modified to higher levels, and the fruitiness of sample S also needs to be adjusted. For a future study, the final compositions of the developed rice wines will be adjusted for product launching based on the preference test data acquired in this study.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.4
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• pp.173-181
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• 2018

Recently composite materials have dominated most engineering fields, owing to their better performance, increased durability and flexibility to be customized and designed for a specific required property. This has given them unprecedented superiority over conventional materials. With the help of the ever increasing computational capabilities of computers, researchers have been trying to develop accurate material models for the complex and integrated properties of these composites. This has led to advances in virtual testing of composite materials as a supplement or a possible replacement of laboratory experiments to predict the properties and responses of composite materials and structures. This paper presents a review on the complex multi-scale modelling framework of the virtual testing machines, which involve computational mechanics at various length-scales starting with nano-mechanics and ending in structure level computational mechanics, with a homogenization technique used to link the different length scales. In addition, the paper presents the features of some of the biggest integrated virtual testing machines developed for study of concrete, including a multiscale modeling scheme for the simulation of the constitutive properties of nanocomposites. Finally, the current challenges and future development potentials for virtual test machines are discussed.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.461-461
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• 2016

이상기후로 인하여 제방붕괴에 대한 위험성이 높아지고 있고, 이로 인해 발생하는 제내지 내 붕괴 홍수파에 대한 연구가 증가하고 있다. 특히 홍수파 선단의 이동 속도 추정은 제내지의 위험성을 예측하고, EAP 등을 수립하는데 매우 중요한 자료가 될 수 있다. 제내지에서의 선단 홍수파에 대한 예측을 하기 위해서는 해당 지역의 하천특성, 수리특성 및 제방 등 수공구조물 특성뿐만 아니라, 제내지의 지형 및 토지이용 현황 등을 조사하여 수리실험이나 수치모의를 수행해야 하는 것이 일반적이다. 수치해석의 경우 수리실험에 비하여 경제성 및 효율성 측면에서 뛰어날 수 있으나, 제방 붕괴과정 및 메커니즘을 반영하기가 불가능하다. 이에 반해 수리모형실험의 경우 제방붕괴 양상 및 그 과정의 재현이 가능하기 때문에, 제내지에서의 선단홍수파 전파에 관한 보다 정확한 양상을 파악할 수 있을 것이다. 그러나 이러한 실험은 실제 크기의 하천이 아닌 축소모형 또는 개수로에서 수행되었기 때문에, 초기 홍수파의 전파가 축척효과(Scale effect)의 영향을 받을 가능성이 매우 크다. 특히 선단 홍수파의 경우 파가 진행되면서 수심이 낮아지고, 유속이 느려지기 때문에 그 영향은 점차 증대된다고 할 수 있다. 이에 본 연구에서는 이러한 초기 선단 홍수파의 표면장력 영향을 고려한 보정 계수 산정에 대한 연구를 수리실험을 통해 수행하였다. 연구는 크게 4가지 과정으로 구성되었다. 첫째는 농도-표면장력의 관계 규명이며, 둘째는 표면장력-홍수파 전파 속도 관계 규명이다. 셋째는 표면장력과 Weber Number(We)의 관계를 도출하는 것이며, 마지막은 We를 이용하여 한계조건을 제시하는 것이다. 실험은 계면활성제의 농도를 변화시켜가며, 얇은 유리관(D=1.0 mm)에서 물의 상승 높이 및 접촉각을 측정하여 농도와 표면장력의 관계를 측정하였으며, 이러한 결과를 바탕으로 물의 표면장력을 변화시켜 가며 $0.5(B){\times}0.3(L){\times}0.2(H)m$의 Head-tank에 설치된 수문을 빠르게 개방하여, 홍수파가 퍼지는 양상을 관측하였다. 홍수파의 이동 속도는 진행시간에 따라서 퍼짐 넓이를 측정하여 제곱근을 취하는 방식으로 평균속도를 산정하였다. 이러한 관계를 이용하여 표면장력이 없을 경우의 이동속도 및 ??를 도출하였다. 본 연구를 통해 홍수파 전파 특성에 대한 수리실험 자료를 바탕으로 Weber 수를 도출하여 표면장력의 영향을 받는지 여부를 판단할 수 있으며, 표면장력의 영향을 받을 경우, 제시된 결과를 이용하여 홍수파 선단의 속도를 보정할 수 있다. 본 연구 결과는 토대로 축소모형으로 수행되는 홍수파 전파에 대한 수리실험결과의 보정 기초자료로 매우 유용할 것으로 판단된다.

• Journal of Life Science
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• v.22 no.10
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• pp.1295-1306
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• 2012

A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater and identified as Bacillus atrophaeus. This species was designated as B. atrophaeus LBH-18 based on its evolutionary distance and the phylogenetic tree resulting from 16S rDNA sequencing and the neighbor-joining method. The optimal conditions for rice bran (68.1 g/l), peptone (9.1 g/l), and initial pH (7.0) of the medium for cell growth was determined by Design Expert Software based on the response surface method; conditions for production of CMCase were 55.2 g/l, 6.6 g/l, and 7.1, respectively. The optimal temperature for cell growth and the production of CMCase by B. atrophaeus LBH-18 was $30^{\circ}C$. The optimal conditions of agitation speed and aeration rate for cell growth in a 7-l bioreactor were 324 rpm and 0.9 vvm, respectively, whereas those for production of CMCase were 343 rpm and 0.6 vvm, respectively. The optimal inner pressure for cell growth and production of CMCase in a 100-l bioreactor was 0.06 MPa. Maximal production of CMCase under optimal conditions in a 100-l bioreactor was 127.5 U/ml, which was 1.32 times higher than that without an inner pressure. In this study, rice bran was developed as a carbon source for industrial scale production of CMCase by B. atrophaeus LBH-18. Reduced time for the production of CMCase from 7 to 10 days to 3 days by using a bacterial strain with submerged fermentation also resulted in increased productivity of CMCase and a decrease in its production cost.