• Title/Summary/Keyword: Chemical Industries

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Bulk Coordination Polymerization of Dicyclopentadiene (DCPD) by Pd Complexes Containing β-Ketoiminate or β-Diketiminate Ligands

  • Lee, Eung Jun;Kim, Ho Sup;Lee, Byoung Ki;Hwang, Woon Sung;Sung, Ik Kyoung;Lee, Ik Mo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4131-4136
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    • 2012
  • Several palladium complexes containing ${\beta}$-ketoiminate and ${\beta}$-diketiminate ligands successfully produced poly(DCPD) possibly via vinyl addition. It was found that catalysts with ${\beta}$-diketiminate ligands containing bulkier aryl substituents showed the highest activity in the presence of MAO as a cocatalyst. Purity of DCPD is quite essential for the higher activity and small amount of organic solvent such as $CH_2Cl_2$ and toluene is required to reduce the viscosity of the reactant mixture for the higher activity. $^1H$ NMR spectra of produced polymers with N,N-dimethylanilinium tetra(pentafluorophenyl)borate (N,N-DAPFAr"$_4$) show that 5,6-double bond of DCPD is removed with 2,3-double bond remaining. Produced poly(DCPD) with MAO cocatalyst is quite rigid and insoluble in common organic solvents but rather brittle.

A method of human error management in chemical process industries (화학공정산업의 인적오류 제어 방법)

  • Jo Young-Do;Park Kyo-Shik;Park Heui-Joon
    • Journal of the Korean Institute of Gas
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    • v.7 no.2 s.19
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    • pp.42-47
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    • 2003
  • To prevent major accident from toxic gas release, explosion, or fire in chemical processes, it needs dynamic control of human error with mechanical failure. Although most of major accidents occur with a coupling of human error and mechanical failure, numbers of researches have studied human error and mechanical reliability independently, but no where cross each other, to reduce the risk in the process. This work focuses on the coincidence of human error and mechanical failure for management of human error, and on some important performance shaping factors to propose a method for improving safety effectively of the process industries.

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Utilization of Kota stone slurry powder and accelerators in concrete

  • Devi, Kiran;Saini, Babita;Aggarwal, Paratibha
    • Computers and Concrete
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    • v.23 no.3
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    • pp.189-201
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    • 2019
  • Recent advances in the concrete technology are aiding in minimizing the use of conventional materials by substituting by-products of various industries and energy sources. A large amount of stone waste i.e., dust and slurry form both are being originated during natural stone processing and causing deadily effects on the environment. The disposal problem of stone waste can be resolved effectively by using waste in construction industries. In present work, Kota stone slurry powder, as a substitution of cement was used along with accelerators namely calcium nitrate and triethanolamine as additives, to study their impact on various properties of the concrete mixtures. Kota stone slurry powder (7.5%), calcium nitrate (1%) and triethanolamine (0.05%) were used separately as well in combination in different concrete mixtures. Mechanical Strength, modulus of elasticity and electrical resistivity of concrete specimens of different mix proportions under water curing were studied experimentally. The durability properties in terms of strength and electrical resistivity against sulphate and chloride solution attack at various curing ages were also studied experimentally. Results showed that accelerators and Kota stone slurry powder separately enhanced the mechanical strength and electrical resistivity; but, their combination decreased strength at all curing ages. The durability of concrete specimens was also affected under the exposure to chemical attack too. Kota stone slurry powder found to be the most effective material among all materials. Material characterization was also done to study the microstructural properties.

Machine learning modeling and DOE-assisted optimization in synthesis of nanosilica particles via Stöber method

  • Moradi, Hiresh;Atashi, Peyman;Amelirad, Omid;Yang, Jae-Kyu;Chang, Yoon-Young;Kamranifard, Telma
    • Advances in nano research
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    • v.12 no.4
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    • pp.387-403
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    • 2022
  • Silica nanoparticles, which have a broad range of sizes and specific surface features, have been used in many industrial applications. This study was conducted to synthesize monodispersed silica nanoparticles directly from tetraethyl orthosilicate (TEOS) with an alkaline catalyst (NH3) based on the sol-gel process and the Stöber method. A central composite design (CCD) is used to build a second-order (quadratic) model for the response variables without requiring a complete three-level factorial experiment. The process was then optimized to achieve the minimum particle size with the lowest concentration of TEOS. Dynamic light scattering and scanning electron microscopy were used to analyze the size, dispersity, and morphology of the synthesized nanoparticles. After optimization, a confirmation test was carried out to evaluate the confidence level of the software prediction. The results revealed that the predicted optimization is consistent with experimental procedures, and the model is significant at the 95% confidence level.

Effects of Non-tariff Measures on Exports (비관세장벽의 수출효과 - 한국을 중심으로)

  • Unjung Whang
    • Korea Trade Review
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    • v.45 no.1
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    • pp.101-118
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    • 2020
  • This study aims to quantify the effects of non-tariff measures (NTMs) on exports in the Korean manufacturing industry. To do this, we employ product-level export data that includes information about whether or not a product is affected by NTMs. One of the main results is that NTMs (SPS/TBT) on average led to reduction in Korean exports. However, the effects of NTMs differed depending on the income level of the NTM-imposing country. The NTMs imposed by high-income countries, such as U.S.A. and Japan, were found to impede Korean exports, whereas the export effect of NTMs imposed by low-income countries such as China was found to not be statistically significant. In addition, the results analyzed based across industries, income level, and types of NTMs are as follows. First, NTMs imposed on textile-related products generally hindered exports regardless of the type of NTMs, but its negative impact on exports was noticeable in the case of NTMs originating from high-income countries. On the other hand, chemical product-related NTMs were found to lead to an increase in Korean exports, and it had a positive effect in the case of SPS imposed by low-income countries. In other industries except for textile- and chemical-related products, the effects of NTMs on exports were either statistically insignificant or showed inconsistent patterns.

Human Toxicity Index and Toxic Substances Emissions in Korea Industries (한국의 산업별 독성물질 배출과 인체유해도 측정 -산업연관분석의 응용-)

  • Rhee, Hae-Chun;Kim, Ik;Hur, Tak
    • Environmental and Resource Economics Review
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    • v.15 no.4
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    • pp.643-672
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    • 2006
  • This study has assessed the industrial human toxicity index by means of toxic substances emissions in South Korean industry. The data used in analysis are the 146 kinds of the toxic chemicals emissions and final demands, total outputs in the input-output table. As a results, human carcinogenic index was $11.86198{\times}10^3$ for overall industries, and $0.26360{\times}10^3$ for average. The industries of higher human toxicity index can be ranked as follows: Mother vehicles and parts (7.85033) > Pig iron and crude steel(4.57409) > Primary iron and steel products(4.36668) > Other transportation equipments and parts(3.43293) > Inorganic basic chemical products(2.64379), etc. Such result can be considered as the priority order of regulation based on industrial characteristics, when the demand and industrial policies should be carried out for the deduction fof toxic substances.

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A study on the flexo printing wastewater treatment and recycling (Flexo 인쇄폐수의 처리 및 재활용에 관한 연구)

  • Jun, Yang-Ba;Hur, Hun;Cho, Kemin;Bae, Woo-Kun
    • Clean Technology
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    • v.9 no.3
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    • pp.107-113
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    • 2003
  • Printing process generates a vast amount of toxical waste and wastewater by the development of printing and publishing industry. The regulations for various environmental pollution material, which were indispensably used in printing industries, were getting stronger. The printing industries should develop the cleaner technologies in order to avoid the regulations. In this paper, the separation characteristics of microfiltration, ultrafiltration, reverse osmosis were surveyed to make basic data for the optimization of process as cleaner technologies for printing industries. The $2kg/cm^2$ of operation pressure were suitable to the U/F System. Because of the permeate of U/F was below 3 NTU as turbidity, which was probed to be possible using the rinsing water in printing process. U/F System,

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A Study on the Induce Effects of Energy Consumption among Industries (산업별 에너지 소비의 유발효과에 관한 연구)

  • Cho, Sang-Sup;Kim, Dong-Yeub;Kang, Shin-Won
    • Environmental and Resource Economics Review
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    • v.18 no.4
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    • pp.637-652
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    • 2009
  • We measure and compare inducements of energy consumption in different industry sectors using inter-industry input and output tables of 1995, 2000 and 2005. We also compute the multiplier effects that relate to the directions of future economic effects. Key Findings are as follows. First, we observe continues decreasing linkage effects in all industries over period of 1995 to 2007. Second, backward multiplier of energy consumption were highest in the material related industry and chemical industry. As for inter-industry inducements, the indirect backward multipliers were high in the other industry. Third, the forward multiplier effect of energy consumption were as same as the backward multiplier effect's sectors. The indirect forward multipliers, however, were highest in the material related industry and chemical industry. The above findings show that since implementing pro-environmental policy in 2000s, the industries structure for reducing energy consumption has been transformed.

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A study on the technological and locational changes of textile industry in Korea (韓國 纖維工業의 技術變化와 立地에 관한 연구)

  • ;Kim, Seon Bae
    • Journal of the Korean Geographical Society
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    • v.38
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    • pp.37-59
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    • 1988
  • The aim of this study is to investigate the influence of the technological changes on locational changes on the assumption that technological changes cover over all industrial sectors. The study is carred on 1) To investigate the theoretical backgrounds of the technological and locational changes and their problems. 2) To investigate the location and economic characteristics of the Korean textile industry. 3) To investigate the technological development and regional variations in technological level. 4) To the relationship of the technological change to the location of the textile industries. The locational change of the Korean textile industries have been closely related to economic characteristics. In the begining stage of development in the 1950's, thetextile industries were largely concentrated in the major cities(Seoul, Pusan, Taegu, Masan et. al.). In the growing stage of development in the 1960's, the textile industries were relocated in suburban areas with the trend of large corporations building their branch plants of chemical fibers in the suburbs. With the expansion in the export industry in the 1970's, the textile companies were distributed throughout the whole country. But the research and development(R&D) activities caused the textile industries reconcentrate around Seoul and Pusan, owining to the change of the economic environments in the 1980's. The 1980's have witnessed the increased R&D investment for the development of better new and value-added products. This was because the technological level was much higher than that of Taegu and Other regions. What is more, plant birth location and branch plant location support that locational changes of textile industry were caused by technological changes. Plant birth location put stress technological environments of region, compared with branch plant locaiton. Accordingly, the technological changes of industry can be an important factor in locational changes. Through this study, it can be seen that locational changes come from technological changes. Other locational factors influence the industrial locations, but regional variations in technological level which has been relatively ignored has to be considered on the location study. Together with the accomplishments of existing location study, the study on technological change and location can better explain the location phenomena. And further research on technological change and location can provide better policy implications for regional development.

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The Effects of the Heavy and Chemical Industry Policy of the 1970s on the Capital Efficiency and Export Competitiveness of Korean Manufacturing Industries (1970년대(年代) 중화학공업정책(重化學工業政策)이 자본효율성(資本效率性)과 수출경쟁력(輸出競爭力)에 미친 영향(影響))

  • Yoo, Jung-ho
    • KDI Journal of Economic Policy
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    • v.13 no.1
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    • pp.65-113
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    • 1991
  • Korea's rapid economic growth of the past thirty years was led by extremely fast export growth under extensive government intervention. Until very recently, the political regimes were authoritarian and oppressed human rights and labor movements. Because of these characteristics, many inside and outside Korea are under the impression that the rapid economic growth was made possible by the government's relentless push for export growth through industrial targetjng. Whether or not the government intervention was pivotal in Korean economic growth is an important issue because of its normative implications on the role of government and the degree of economic policy intervention in a market economy. A good example of industrial targeting policy in Korea is the "Heavy and Chemical Industry (HCI)" policy, which began in the early 1970s and lasted for one decade. Under the HCI policy the government intervened in resource allocation through preferential tax, trade, and credit and interest rate policies for "key industries" which included iron and steel, non-ferrous metals, shipbuilding, general machinery, chemicals, and electronics. This paper investigates the effects of. the HCI policy on the efficiency of capital and the export competitiveness of manufacturing industries. For individual three-digit KSIC (Korea Standard Industrial Classification) industries and for two industry groups, one favored by HCI Policy and the other not, this paper: (1) computes capital intensities and discusses the impact of the HCI policy on the changes in the intensities over time, (2) estimates the capital efficiencies and examines them on the basis of optimal condition of resource allocation, and (3) compares the Korean and Taiwanese shares of total imports by the OECD countries as a way of weighing the effects of the policy on the industries' export competitiveness. Taiwan is a good reference, as it did not adopt the kind of industrial targeting policy that Korea did, while the Taiwanese and Korean economies share similar characteristics. In the 1973-78 period, the capital intensity rose rapidly for the "HC Group" the group of industries favored by the policy, while it first declined and later showed an anemic rise for the "Light Group," the remaining manufacturing industries. Capital efficiency was much lower in the HC Group than in the Light Group, at least until the late 1970s. This paper acribes these results to excess investments in the favored industries and concludes that growth could have been faster in the absence of the HCI policy. The Korean Light Group's share in total imports by the OECD was larger than that of its Taiwanese counterpart but has become much smaller since 1978. For the HC Group Korea's market share was smaller than Taiwan's and has declined even more since the mid-1970s. This weakening in the export competitiveness of Korea's industries relative to Taiwan's lasted until the mid-1980s. This paper concludes that the HCI policy had either no positive effect on the competitiveness of the Korean manufacturing industries or negative effects.

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