• Carbon letters
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• v.9 no.3
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• pp.188-194
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• 2008

Porous carbon materials synthesized from various plant derived precursors i.e. seeds of [Castor (Ricinus communis), Soap nut (Sapindus sp.), Cashew-nut (Semecarpus anacardium), Jack fruit (Artocarpus heterophyllus), Safflower (Carthamus tinctorius), Ambadi (Crotolaria juncea), Neem (Azadirachta indica), Bitter Almond (Prunus amygdalus), Sesamum (Sisamum indicum), Date-palm (Phoenix dactylifera),Canola (Brassica napus), Sunflower (Helianthus annulus)] and fibrous materials from [Corn stem- (Zea mays), Rice straw (Oryza sativa), Bamboo (Bombax bambusa) and Coconut fibers (Cocos nucifera)] were screened to make supercapacitor in 5M KOH solution. Carbon material obtained from Jack fruit seeds (92.0 F/g), Rice straw (83.0 F/g), Soap nut seeds (54.0 F/g), Castor seeds (44.34 F/g) and Bamboo (40.0 F/g) gave high capacitance value as compared to others. The magnitude of capacitance value was found to be inversely proportional to the scan rate of measurement. It is suggested that carbon material should possess large surface area and small pore size to get better value of capacitor. Moreover, the structure of carbon materials should be such that majority of pores are in the plane parallel to the plane of electrode and surface is fluffy like cotton ball.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.119-130
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• 2020

With the current rapid growth and increase in the world's population, the demand for nutritious food and fibers and fuel will increase. Therefore, there is a serious need for the use of breeding programs with the full potential to produce high-yielding crops. However, existing breeding techniques are unable to meet the demand criteria even though genotyping techniques have significantly progressed with the discovery of molecular markers and next-generation sequencing tools, and conventional phenotyping techniques lag behind. Well-organized high-throughput plant phenotyping platforms have been established recently and developed in different parts of the world to address this problem. These platforms use several imaging techniques and technologies to acquire data for quantitative studies related to plant growth, yield, and adaptation to various types of abiotic or biotic stresses (drought, nutrient, disease, salinity, etc.). Phenotyping has become an impediment in genomics studies of plant breeding. In recent years, phenomics, an emerging domain that entails characterizing the full set of phenotypes in a given species, has appeared as a novel approach to enhance genomics data in breeding programs. Imaging techniques are of substantial importance in phenomics. In this study, the importance of current imaging technologies and their applications in plant phenotyping are reviewed, and their advantages and limitations in phenomics are highlighted.

• Membrane and Water Treatment
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• v.9 no.1
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• pp.43-51
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• 2018

Hollow fiber (HF) membranes are gaining wide interest over flat membranes due to their compaction and high area to surface volume ratio. This work addresses the fabrication of HF from polysulfone (PS) and polyethersulfone (PES) using N-methylpyrrolidone (NMP) as solvent in addition to other additives to achieve desired characteristics. The semi-pilot spinning system includes jacketed vessel, four spinneret block, coagulation and washing baths in addition to dryer and winder. Different parameters affecting dry-wet spinning phase inversion process were investigated. Dope compositions of PES, NMP and polyvinyl pyrrolidone (PVP) of varying molecular weights as additive were addressed. Some critical parameters of importance were also investigated. Those include dope flow rate, air gap, coagulation & washing baths and drying temperatures. The measured dope viscosity was in the range from 1.7 to 36.5 Pa.s. Air gap distance was adjusted from 20 to 45 cm and coagulation bath temperature from 20 to $46^{\circ}C$. The HF membranes were characterized by scanning electron microscope (SEM), atomic force microscope (AFM) and mechanical properties. Results indicated prevalence of finger like structure and average surface roughness from about 29 to 78.3 nm. Profile of stress strain characteristics revealed suitability of the fibers for downstream interventions for fabrication of thin film composite membrane. Different empirical correlations were formulated which enable deeper understanding of the interaction of the above mentioned variables. Data of pure water permeability (PWP) confirmed that the fabricated samples fall within the microfiltration (MF)-ultrafiltration (UF) range of membrane separation.

• 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.

• Journal of Plant Biology
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• v.34 no.1
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• pp.9-18
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• 1991

This study deals with the effect of dwarf growth on xylem structure, especially on the dimension of xylem elements described for 12 species of naturally occuring dwarf trees. The length and tangential diameter of tracheary elements and fibers in dwarf trees appear to be shorter and narrower than those in normal trees. Radial width and cell number of the same annual rings are narrower and smaller in dwarf trees than those in normal trees. Height of rays in dwarf trees is lower than that in normal trees. Dwarf conifers appear to have higher ratio, of latewood to earlywood than that in normal trees. In the hardwood species studied, mesomorphy of vessel elements is lower in dwarfs than that in normal trees. It can be concluded that this dwarf growth occurs as a result of extremely slow growth by environmental stress such as water deficiency.ciency.

• Membrane Journal
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• v.17 no.3
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• pp.197-209
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• 2007

In this study, a multi-staged pilot-scale membrane plant was constructed and operated for the separation of $CO_2$ from LNG-fired boiler flue gas of 1,000 $Nm^3/day$. The target purity and recovery ratio of $CO_2$ required for the pilot plant were 99% and 90%, respectively. For this purpose, we previously developed the asymmetric polyethersulfone hollow fibers and evaluated the effects of operating pressure and feed concentration of $CO_2$ on separation performance[1,2]. The permeation data obtained were also analyzed in relation with the numerical simulation data using counter-current flow model[3,4]. Based on these results, we designed and prepared the demonstration plant consisting of dehumidification process and four-staged membrane process. The operation results using this plant were compared with the numerical simulation results on multi-staged membrane process. The experimental results matched well with the numerical simulation data. The concentration and the recovery ratio of $CO_2$ in the final stage permeate stream were ranged from $95{\sim}99%$ and $70{\sim}95%$, respectively, depending on the operating conditions. This study demonstrated the applicability of the membrane-based pilot plant for $CO_2$ recovery from flue gas.

• Korean Journal of Pharmacognosy
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• v.6 no.3
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• pp.125-129
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• 1975

The pharmacognostical and pharmacological studies of 'Manryong' were carried out, which has been widely used in Chun-Ra Province, Korea and the following results were obtained. 1) The original plant of the bulb MANRYONG is Erythronium japonicum DECNE. (Liliaceae). 2) The internal structure consists of mostly parenchyma containing numerous starch grains, vascular bundles and substituted fibers. 3) The external surface occurs as a yellowish white and slightly bented ovoidal shape. 4) 'Manryong; contains 11 kinds of free amino acids, such as asparagin, tryptophan, cystine, glutamic acid, threonine, glycine, leucine, proline, histidine, methionine, and alanine. 5) Hemolytic action of the crude saponin isolated from 'Manryong' is weaker than that of digitonin. 6) Effects of 'Manryong' extracts on ceruloplasmin were studied and an antidotal activity of the extracts was found in liver intoxicated with carbon tetrachloride.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.37-42
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• 2006

The paper discusses the combined use of softwood and eucalyptus kraft pulps in the production of printing and writing papers. Looking for process and paper quality optimization, refining pilot plant trails were carried to identify the effects of refining type (mixed or separate) and intensities (specific edge load), and also furnish composition (amount of each pulp in mixture) on final paper quality and process costs. The basic effects on pulp fibers were evaluated against paper quality properties, such as physical strengths, bulk, vessel picking, opacity and porosity, as well as the interactions with papermaking process, such as estimates of paper machine runnability, paper breaks and industrial refining control. The results show that the furnish composition and the type of refining has a significant effect on properties related with both final paper quality and total costs. The best alternative for printing and writing papers was identified for mixed refining, under the lowest refining intensity, and with the highest dosage of eucalyptus pulp.

• Carbon letters
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• v.7 no.4
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• pp.245-248
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• 2006

Thin films of carbon-nano materials (CNMs) of different morphology have been successfully deposited on ceramic substrate by CVD at temperatures $800^{\circ}C$, $850^{\circ}C$ and $900^{\circ}C$ using plant based oils in the presence of transition metal catalysts (Ni, Co and Ni/Co alloys). Based on the return and insertion loss, microwave absorption properties of thin film of nanocarbon material are measured using passive micro-Strip line components. The result indicates that amongst CNMs synthesized from oil of natural precursors (mustered oil - Brassica napus, Karanja oil - Pongamia glabra, Cotton oil - Gossipium hirsuta and Neem oil - Azadirachta indica) carbon nano fibers obtained from neem's seed oil showed better microwave absorption (~20dB) in the range of 8.0 GHz to 17.90 GHz.

• Elastomers and Composites
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• v.56 no.2
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• pp.85-91
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• 2021

In this study, different types and shapes of various particles produced on the asphalt pavement road were analyzed. Road dust at a bus stop was collected and was separated as per their sizes by using a sieve shaker. Tire-road wear particles (TRWPs), asphalt pavement wear particles (APWPs), mineral particles, plant-related particles, glass beads, glass particles, road paint wear particles, plastic particles, and fibers were observed herein. The types and shapes of the particles varied depending on their sizes. TRWPs larger than 500 ㎛ were not observed. TRWPs with a size of 212-500 ㎛ were rarely present, but many TRWPs with a size smaller than 212 ㎛ were observed. APWPs were observed for whole-particle sizes of below 1,000 ㎛. A variety of particles on the road would lead to lower friction between the tires and the road, thereby increasing the braking distance of vehicles. Most of the particles include mineral particles, glass particles, and APWPs with rough surfaces. Therefore, the abrasion of the tire tread would accelerate owing to friction with the tough particles.