• KSBB Journal
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• v.18 no.6
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• pp.473-478
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• 2003

The purpose of this study is to look for the optimal conditions of methane production. The conditions tested for methane production enhancement were temperature, pH, carbon source, nitrogen source, and inhibitor which can affects methane production. As a result, optimal conditions for methane production were 30$^{\circ}C$, neutral pH, methanol as a carbon source, NH$_4$Cl as a nitrogen source. 2-Bromoethanesulfonic acid was used as an inhibitor which can affects methane production. Existence in broth less than 10mM, inhibited methane production. Organic acid measurements revealed that formic acid exists in broth as majority.

• Journal of the Korean Applied Science and Technology
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• v.8 no.2
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• pp.175-181
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• 1991

The kinetics of the addition of 1-benzylindole-3-(p-substituted) acetophenone derivatives was investigated by ultraviolet spectrophotometery in 30% dioxane -$H_2O\;at\;25^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The Substituent effects on 1-benzylindole-3-(p-substituted) acetophenone derivatives were studied, and addition were facilitated by electron attracting groups. On the base of the rate equation, substituent effect, and general base effect the plausible addition mechanism was proposed : Below pH 3.0, only neutral thiourea molecule was added to the carbon-carbon double bond, and in the range of pH 0.0${\sim}$14.0, netural thiourea molecule and thiourea anion competitively attacted the double bond. By contrast, above pH 10.0, the reaction was dependent upon only the addition of thiourea anion.

• New & Renewable Energy
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• v.18 no.3
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• pp.72-84
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• 2022

As the threat of climate change escalates, 'net-zero' has become a priority for the international community, and the use of new and renewable energy sources is expected to play a significant role in reaching international carbon neutrality. Here, we evaluate technological competitiveness in terms of implementation and technology by analyzing scientific literature and patents in the new and renewable energy fields of five major countries. For the past 10 years (2009-2019), the most active areas of new and renewable energy research and development have been solar power, wind power, waste, and fuel cells. China is the forerunner in implementation, whereas the United States has the most advanced technology. Portfolio analysis revealed that Korea's fuel cell, the United States' bioenergy, China's waste, Japan's solar and fuel cell, and the European Union's wind power have shown to be in Star Field respectively. Technological competitiveness analysis found that Korea is lagging behind other countries in the new and renewable energy sector, and needs to set a new direction for future carbon-neutral research and development, investment, and policy.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.9-22
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• 2023

Spin-off pyroprocessing technology and inert anode materials to replace the conventional carbon-based smelting process for critical materials were introduced. Efforts to select inert anode materials through numerical analysis and selected experimental results were devised for the high-throughput reduction of oxide feedstocks. The electrochemical properties of the inert anode material were evaluated, and stable electrolysis behavior and CaCu generation were observed during molten salt recycling. Thereafter, CuTi was prepared by reacting rutile (TiO₂) with CaCu in a Ti crucible. The formation of CuTi was confirmed when the concentration of CaO in the molten salt was controlled at 7.5mol%. A laboratory-scale electrorefining study was conducted using CuTi(Zr, Hf) alloys as the anodes, with a Ti electrodeposit conforming to the ASTM B299 standard recovered using a pilot-scale electrorefining device.

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.193-200
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• 2023

This paper selects 100 IT companies listed on the Shenzhen Stock Exchange from 2016 to 2020, and the public announcement in Hwajung collects ESG integrated ratings and grades for each sector and empirically verifies the relationship between ESG ratings and stock returns. Huazheng ESG level data and QIANZHAN database Using corporate financial data, a total of 500 samples were selected through correlation analysis and linear regression analysis with SPSS23 to analyze the effect of ESG on Return. As a result of the analysis, first, the impact on stock returns was found to be a significant positive (+) value for ESG integrated ratings and ratings by E (environment), S (social), and G (governance) sectors, confirming that ESG ratings have a positive mold of corporate stock returns. Currently, the world's major economies have proposed sustainable development strategies and "carbon neutral" goals. Development strategies are very consistent with ESG concepts, and companies that agree and execute ESG concepts may have higher ratings than other companies in the same industry, resulting in certain evaluation premiums. In addition, capital market performance in recent years shows that companies with ESG concepts or "carbon neutrality" concepts are generally considered to have higher growth potential and stronger anti-risk capabilities in the market. For listed companies, they should focus on ESG investment, improve ESG performance, and actively disclose related information to investors. Improving ESG performance should deliver positive information to society, enhance corporate image, increase market confidence in the future development of listed companies, and positively improve corporate value to actively increase financial, financial, trading, and other aspects of negotiation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.41-42
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• 2021

The Green New Deal policy was established to innovate the government's energy consumption structure, establish a third basic energy plan to strengthen the global competitiveness of the energy industry, and realize a carbon neutral society due to the increased need for transition to a low-carbon economy. Waterworks such as drinking water, water purification plant, and pressurization plant analyze control factors and energy consumption status by process to improve energy management efficiency and reduce energy usage through the 4th industrial revolution. Ultimately, we want to realize net-zero water purification plant.

• International Journal of Advanced Culture Technology
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• v.11 no.2
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• pp.389-396
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• 2023

This paper selects 100 IT companies listed on the Shenzhen Stock Exchange from 2016 to 2020, and the public announcement in Hwajung collects ESG integrated ratings and grades for each sector and empirically verifies the relationship between ESG ratings and stock returns. Huazheng ESG level data and QIANZHAN database Using corporate financial data, a total of 500 samples were selected through correlation analysis and linear regression analysis with SPSS23 to analyze the effect of ESG on Return. As a result of the analysis, first, the impact on stock returns was found to be a significant positive (+) value for ESG integrated ratings and ratings by E (environment), S (social), and G (governance) sectors, confirming that ESG ratings have a positive mold of corporate stock returns. Currently, the world's major economies have proposed sustainable development strategies and "carbon neutral" goals. Development strategies are very consistent with ESG concepts, and companies that agree and execute ESG concepts may have higher ratings than other companies in the same industry, resulting in certain evaluation premiums. In addition, capital market performance in recent years shows that companies with ESG concepts or "carbon neutrality" concepts are generally considered to have higher growth potential and stronger anti-risk capabilities in the market. For listed companies, they should focus on ESG investment, improve ESG performance, and actively disclose related information to investors. Improving ESG performance should deliver positive information to society, enhance corporate image, increase market confidence in the future development of listed companies, and positively improve corporate value to actively increase financial, financial, trading, and other aspects of negotiation.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.831-840
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• 2013

In this study, an attempt is being made to extract surface-active substances from defatted rapeseed cakes by supercritical carbon dioxide fluid. Independent variables for the extraction process, being formulated by D-optimal design, are pressure (150~350 bar), temperature ($33{\sim}65^{\circ}C$ and co-solvent (ethanol, 50~250 g). The dependent variables of the extraction yield, the content of neutral lipids, phospholipids and glycolipids in the extracts were analyzed upon the results through the response surface methodology. As for the extraction yield, it was found to increase with increasing independent variables, among which the co-solvent proved to be a major influencing parameter. Similar trends were found for the content of surface-active substances (i.e, phospholipids and glycolipids) in the extracts, except for the content of neutral lipids. Regression equations were suggested to coincide well with the results from the experiments. Extraction conditions are being optimized to maximize the extraction yields, the content of phospholipids, and glycolipids were 350 bar (pressure), $65^{\circ}C$ (temperature) and 228.55 g (co-solvent), respectively.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.332-340
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• 2009

This study was conducted to analyze and determine formation potentials for chlorination disinfection by-products (DBPs) from twenty amino acid compounds with or without $Br^-$. Two of twenty amino acid compound were tryptophan and tyrosine that were relatively shown high for formation of trihalomethanes (THMs)/dissolved organic carbon (DOC) whether or not $Br^-$ presented. Other 18 compounds were shown low for formation of THMs/DOC whether or not $Br^-$ presented. Five amino acid compounds that were tryptophan, tyrosine, asparagine, aspartic acid and histidine were shown high for formation of haloacetic acids (HAAs)/DOC whether or not $Br^-$ presented. Although formation of dichloroacetic acid (DCAA) was dominated in asparagine, aspartic acid and histidine, trichloroacetic acid (TCAA) was dominated in tryptophan and tryptophan. The formation of haloacetnitriles (HANs)/DOC whether or not $Br^-$ presented was high in Aspartic acid, histidine, asparagine, tyrosine and tryptophan. Specially, aspartic acid was detected 660.2 ${\mu}$g/mg (HAN/DOC). Although the formation of chloralhydrate (CH)/DOC was shown high in asparagine, aspartic acid, histidine, methionine, tryptophan and tyrosine, the formation of Chloropicrin (CP)/DOC was low (1 ${\mu}$g/mg) in twenty amino acid compounds. The formations of THM, HAA and HAN were also investigated in functional groups of amino acids. The highest formation of THM was shown in amino acids compounds (tryptophan and tyrosine) with an aromatic functional group. Highest, second-highest, third-highest and fourth-highest functional groups for formation of HAA were aromatic, neutral, acidic and basic respectively. In order of increasing functional groups for formation of HAN were acidic, basic, neutral and aromatic.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.1
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• pp.81-90
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• 2003

To understand the thermoresponsive volume phase transition of an N-isopropyl acrylamide(NIPA) gel on water, the solubility parameter of neutral NIPA gel was determined by swelling the gel with various solvents. Water was found not to be a good solvent for NIPA gel. Equilibrium swelling curves of NIPA gel were respectively obtained by immersing in pure water, ethanol, n-propanol and some mixed solvents. On adding a small amount of alcohols to water, volume phase transition of NIPA gel in water was changed. Phase transition temperature of this gel was decreased with the increase of the carbon number of alcohol.