• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.26-39
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• 2014

Cu interconnection in electronic devices is fabricated via damascene process including Cu electrodeposition. In this review, Cu electrodeposition and superfilling for fabricating Cu interconnection are introduced. Superfilling results from the influences of organic additives in the electrolyte for Cu electrodeposition, and this is enabled by the local enhancement of Cu electrodeposition at the bottom of filling feature formed on the wafer through manipulating the surface coverage of organic additives. The dimension of metal interconnection has been constantly reduced to increase the integrity of electronic devices, and the width of interconnection reaches the range of few tens of nanometer. This size reduction raises the issues, which are the deterioration of electrical property and the reliability of Cu interconnection, and the difficulty of Cu superfilling. The various researches on the development of organic additives for the modification of Cu microstructure, the application of pulse and pulse-reverse electrodeposition, Cu-based alloy superfilling for improvement of reliability, and the enhancement of superfilling phenomenon to overcome the current problems are addressed in this review.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.17-23
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• 2008

In order to prevent wine quality deterioration caused by strong sour taste from raw and other materials during fermentation of wild grape wine, the various mixed cultures conditions of the deacidification fermentation and the alcohol fermentation process by inoculation of mixed strains were investigated. As a result of mixed cultures process after the inoculation of Schizosaccharomyces pombe and Schizosaccharomyces japonicus with each deacidification fermentation strain in a culture of Saccharomyces sp. SMR-3 which was used in the alcohol fermentation strain of wild grape, cultures for 12 days at $22^{\circ}C$ with Saccharomyces sp. SMR-3 and Schizosaccharomyces pombe resulted in the maximum alcohol content at $15.8{\pm}0.2%$ and the minimum with the acidity of $0.44{\pm}0.02%$, the total organic acid of $648.96{\pm}7.14$ mg% and malic acid of $99.30{\pm}1.24$ mg%. Mixed cultures with Saccharomyces sp. SMR-3 and Schizosaccharomyces pombe under the optimal condition for the deacidification fermentation of wild grape wine showed 2% higher alcohol content, 51.65% lower acidity, 48.02% lower total organic acid, and 81.12% lower malic acid than a single culture of Saccharomyces sp. SMR-3.

• Korean Journal of Biological Psychiatry
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• v.27 no.2
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• pp.42-57
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• 2020

Electroconvulsive therapy (ECT) is indicated for various mental disorders (e.g., major depressive disorder, schizophrenia, and bipolar disorder) and the behavioral and psychological symptoms of dementia in elderly patients. Furthermore, ECT is a useful first-line treatment in emergency and crisis situations such as suicide risk, violent behavior, catatonia, and food refusal, which are more frequent in elderly patients. ECT is also effective in the treatment of the motor symptoms of neurological disorders, such as Parkinson's disease and Huntington's disease. Due to the high risk of various physical diseases, the comorbid physical conditions of elderly patients should be individually controlled to optimize ECT treatment. Compared to young adults, in elderly patients the seizure threshold is higher, the seizure duration is shorter, and the anesthetic dose is lower. On the contrary, the response rate in the elderly is both faster and higher. Considering potential cognitive decline and the prevention of further deterioration of cognitive function in elderly patients, in the absence of significant comorbidities, twice weekly sessions and right unilateral electrode placement with a lower seizure threshold and less cognitive effect are preferred to bilateral electrode placement, which has a high risk of adverse cognitive effects. After an acute course of ECT, continuation and maintenance of ECT, combined with prescription of therapeutic drugs, may prevent possible relapse or recurrence of mental disorders. In conclusion, ECT can be used to treat mental disorders in elderly adults, with safety and effectiveness comparable to that in young adults.

• Journal of Microbiology and Biotechnology
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• v.31 no.6
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• pp.803-814
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• 2021

A pilot-scale biocover was constructed at a sanitary landfill and the mitigation of methane and odor compounds was compared between the summer and non-summer seasons. The average inlet methane concentrations were 22.0%, 16.3%, and 31.3%, and the outlet concentrations were 0.1%, 0.1%, and 0.2% during winter, spring, and summer, respectively. The odor removal efficiency was 98.0% during summer, compared to 96.6% and 99.6% during winter and spring, respectively. No deterioration in methane and odor removal performance was observed even when the internal temperature of the biocover increased to more than 40℃ at midday during summer. During summer, the packing material simultaneously degraded methane and dimethyl sulfide (DMS) under both moderately thermophilic (40-50℃) and mesophilic conditions (30℃). Hyphomicrobium and Brevibacillus, which can degrade methane and DMS at 40℃ and 50℃, were isolated. The diversity of the bacterial community in the biocover during summer did not decrease significantly compared to other seasons. The thermophilic environment of the biocover during summer promoted the growth of thermotolerant and thermophilic bacterial populations. In particular, the major methane-oxidizing species were Methylocaldum spp. during summer and Methylobacter spp. during the non-summer seasons. The performance of the biocover remained stable under moderately thermophilic conditions due to the replacement of the main species and the maintenance of bacterial diversity. The information obtained in this study could be used to design biological processes for methane and odor removal during summer and/or in subtropical countries.

• Research in Plant Disease
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• v.28 no.3
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• pp.152-161
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• 2022

Several types of chemical bactericides have been used to control fire blight. However, their excessive usage leads to environmental deterioration. Therefore, several researchers have analyzed antagonistic microorganisms as promising, effective, and safe biological control agents (BCAs). The primary aim of this study was to screen for potential antagonistic bacteria that suppress Erwinia amylovora. Among the 45 isolates studied, 5 strains showed the largest inhibition zone against E. amylovora. 16S rRNA gene sequencing identified them as Bacillus amyloliquefaciens (KPB 15), B. stratosphericus (KPB 21), B. altitudinis (KPB 25), B. safensis (KPB 31), and B. subtilis (KPB 39). KPB 25 and 31 reduced the lesion size of fire blight by 50% in immature apple fruits, and did not show antagonism against each other. Therefore, KPB 25 and 31 were selected to develop an antagonistic mixture against fire blight. Although the mixture with KPB 25 and 31 showed a slightly increased ability to reduce lesion size on immature fruits, they did not exhibit a synergistic effect in reducing E. amylovora population compared to each strain alone. Nevertheless, we have identified these two strains as useful and novel BCAs against fire blight with additional benefits safety and potential in developing a mixture without loss of their activity, owing to the absence of antagonism against each other.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.574-580
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• 2014

Storage tanks of Carbon dioxide ($CO_2$) carriers utilized for the purpose of carbon capture and storage (CCS) into subsea strata have to undergo a pre-cooling session before beginning to load cryogenic liquid cargos in order to prevent physical and thermal deterioration of tanks which may result from cryogenic $CO_2$ contacting tank walls directly. In this study we propose dynamic model to calculate the tank inflow of $CO_2$ gas injected for precooling process and its dynamic simulation results under proportional-integral control algorithm. We selected two cases in which each of them had one controlled variable (CV) as either the tank pressure or the tank temperature and discussed the results of that decision-making on the pre-cooling process. As a result we demonstrated that the controlling instability arising from nonlinearity and singularity of the mathematical model could be avoided by choosing tank pressure as CV instead of tank temperature.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.87-92
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• 2005

The structural differences between healthy and diseasedpanicle necks caused by Pyricularia oryzae were observed using electron-microscope. In the diseased panicle neck, the infection hyphae of the rice blast pathogen grew through the sclerenchymatous fiber tissue and reached to the central internal lacuna. Since the pathogen grew through the sclerenchymatous fiber tissues, the vascular bundle composed with xylem and phloem had been destroyed and finally the nutrients from the leaf and stem were not able to be transported into the grains. Infection of panicle base by the blast pathogen until 20 days after heading caused more than 50% of yield loss in both Jinmibyeo and Chucheongbyeo. There was a positive correlation between incidence of the panicle blast and rice yield losses. The regression equations between incidence of the panicle blast and yield losses were y= -3.61+496.7 ($R^2$=0.70) in Jinmibyeoand y=-3.93+520.2 ($R^2$=0.82) in Juanbyeo. The panicleblast caused deterioration of grain quality. Healthy grain rate was reduced by increase of panicle blast infection.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.29-37
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• 2012

The West Stone Pagoda at Gameunsaji Temple Site constructed in the 7th century is mainly composed of dark grey dacitic tuff bearing small numerous dioritic xenoliths. These xenoliths resulted in small holes due to differential weathering process from the host rocks. Physical strength of the pagoda was decreased due to weathering and damage caused by petrological, biological and coastal environmental factors. The southeastern part of the pagoda was extremely deteriorated that the rock surface showed exfoliation, fracture, open cavity, granular decomposition of minerals and salt crystallization by seawater spray from the eastern coast. The stone blocks were intersected by numerous cracks and contaminated by subsequent material such as cement mortar and iron plates. Also, the pagoda was colonized by algae, fungi, lichen and bryophytes on the roof rock surface and the gaps between the blocks. As a result of ultrasonic test, the rock materials fell under Highly Weathered Grade (HW) or Completely Weathered Grade (CW). Thus, conservational intervention is essentially required to prevent further weakening of the rock materials.

• Advances in environmental research
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• v.9 no.3
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• pp.151-160
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• 2020

Water quality demonstrates physical, chemical and biological characteristics of water. The quality of surface and groundwater is currently an important concern with population growth and industrialization. Over exploitation of water resources due to demand is causing the deterioration of surface water and ground water. Periodic water quality testing must be carried out to protect our water resources. The present research analyses the spatial variation of surface water and groundwater in and around the lakes of Hyderabad. Twenty-Seven lakes and their neighboring bore water samples are obtained for water quality monitoring. Samples are evaluated for specific physico-chemical parameters such as pH, Total Dissolved Solids (TDS), Cl, SO₄, Na, K, Ca, Mg, and Total Hardness (TH). The spatial variation of water quality parameters for the 27 lakes and groundwater were analysed. Correlation and multiple regression analysis were carried out to determine comparative study of lake and ground water. The study found that most of the lakes were polluted and this had an impact on surrounding ground water.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.20-26
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• 2010

Paper composed mainly of organic materials and they can be used as nutrient by microorganisms. Therefore microorganisms are damaging the important documents and works of art irreversibly. Previous research reported that mycelium or spores of the fungi were observed on the wax of the volumes of King Sejong especially were heavily deteriorated by fungi. Fungal strains isolated from the annals of Joseon dynasty were identified as Biscogniauxia atropunctata, Aspergillus versicolor, Penicillium polonicum, Ceriporia lacerata, Irpex lacteus. Especially Aspergillus and Penicillium are able to grow on the substrates having a 7-8% moisture content, which is much lower than the general storage condition (RH55-60%) of the paper cultural properties. Moreover, they are known as fungi cause paper deterioration and discoloration. In this study, we selected Aspergillus versicolor and Penicillium polonicum among five strains, then biological aging has been executed for 30 days. The growth of Aspergillus versicolor and Penicillium polonicum in wax was lower than wax treated paper and Hanji. The growth of them in beeswax treated paper and Hanji both were excellent.