• Advances in environmental research
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• v.7 no.2
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• pp.139-159
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• 2018

Green Leaf Volatiles (GLVs) is a class of biogenically emitted oxygenated hydrocarbons that have been identified as a potential source of Secondary Organic Aerosols (SOA) via aqueous oxidation. The physico-chemical properties of GLVs are vital to understanding their fate and transport in the atmosphere via fog processing, but few experimental data are available. We studied the aqueous solubility, 1-octanol/water partition coefficient, and Henry's law constant ($K_H$) of five GLVs at $25^{\circ}C$: methyl jasmonate, methyl salicylate, 2-methyl-3-buten-2-ol, cis-3-hexen-1-ol, and cis-3-hexenyl acetate. Henry's law constant was also measured at temperatures and ionic strengths typical of fog. Experimental values are compared to scarcely-available literature values, as well as estimations using group and bond contribution methods, property-specific correlations and molecular dynamics simulations. From these values, the partition coefficients to the air-water interface were also calculated. The large Henry's law constant of methyl jasmonate ($8091{\pm}1121M{\cdot}atm^{-1}$) made it the most significant GLV for aqueous phase photochemistry. The HENRYWIN program's bond contribution method from the Estimation Programs Interface Suite (EPI Suite) produced the best estimate of the Henry's constant for GLVs. Estimations of 1-octanol/water partition coefficient and solubility are best when correlating an experimental value of one to find the other. Finally, the scavenging efficiency was calculated for each GLV indicating aqueous phase processing will be most important for methyl jasmonate.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.75-82
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• 2008

Functional stay-green is a beneficial trait that may increase grain yield through the sustained photosynthetic competence during monocarpic senescence in cereal crops. The temporal changes of photosynthesis and related characteristics throughout the grain filling period of a stay-green japonica rice "SNU-SG1" was compared in growth chamber conditions with three high-yielding cultivars(HYVs) and their $F_1$ hybrids with SNU-SG1. SNU-SG1 exhibited a typical characteristic of functional stay-green in terms of chlorophyll degradation and photosynthetic competence during grain filling. According to the photosynthesis-light response curve measured at 10 and 35 d after heading for the flag leaf, SNU-SG1 exhibited higher initial light conversion efficiency and thus higher gross photosynthetic rate at light saturation compared to HYVs. Light saturation point was not different among genotypes, ranging from 1000 to 1500 ${\mu}mol$ photon $m^{-2}s^{-1}$. Net photosynthetic rate at light saturation($P_{max}$) of the upper four leaves in SNU-SG1 was much higher and sustained longer throughout grain-filling than HYVs and $F_1$ hybrids. The sustained high photosynthetic competence of SNU-SG1 during grain filling was ascribed to the longer maintenance of high mesophyll conductance that resulted from not only high chlorophyll content and its delayed degradation but also the slow degeneration of photosystem II(PS II) as judged by chlorophyll fluorescence($F_v/F_m$) of flag leaves. $F_1$ hybrids showed slow degeneration of photosystem II similar to the male parent SNU-SG1 while chlorophyll degradation pattern close to female parents, thus exhibiting a little higher $P_{max}$ than female parents. These results suggest that SNU-SG1 has a typical functional stay-green trait that can be utilized for increasing rice yield potential through the improved dry matter production during grain filling.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1483-1490
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• 2017

In this study, silver nanoparticles (AgNPs) were synthesized by the citrate reduction process and, with the assistance of n-hydroxysuccinimide and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, were successfully loaded with the macromolecular drug vancomycin (VAM) to form AgNP-VAM bioconjugates. The synthesized AgNPs, VAM, and AgNP-VAM conjugate were characterized by UV-visible spectroscopy, zeta potential analysis, confocal microscopy, and transmission electron microscopy. The effect of loading VAM onto AgNPs was investigated by testing the internalization of the bioconjugate into Mycobacterium smegmatis. After treatment with the AgNP-VAM conjugate, the bacterial cells showed a significant decrease in UV absorption, indicating that loading of the VAM on AgNPs had vastly improved the drug's internalization compared with that of AgNPs. All the experimental assessments showed that, compared with free AgNPs and VAM, enhanced internalization had been successfully achieved with the AgNP-VAM conjugate, thus leading to significantly better delivery of the macromolecular drug into the M. smegmatis cell. The current research provides a new potential drug delivery system for the treatment of mycobacterial infections.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.169-170
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• 2006

Advanced melting technology is now being employed in the manufacture of stainless steel powders. The new process currently includes electric arc furnace (EAF) technology in concert with Argon Oxygen Decarburization (AOD), High Performance Atomizing (HPA) and hydrogen annealing. The new high performance-processing route has allowed the more consistent production of existing products, and has allowed enhanced properties, such as improved green strength and green density. This paper will review these processing changes along with the potential new products that are being developed utilizing this technology. These include high strength stainless steels such as duplex and dual phase as well as stainless steel powders used in high temperature applications such as diesel filters and fuel cells.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.230-235
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• 2008

The aquatic fern Azolla spp. is of value as a bio-fertilizer for wetland paddy. It is popular and cultivated widely in other countries like China, Vietnam, and the Philippines, but has yet to be taken up in Korea, in a big way. It fixes nitrogen as high as 3-5kg N per day, because it contains nitrogen fixing blue-green algae, Anabaena azollae. Azolla's ability to create a light-proof mat that suppresses other weeds has been used for centuries in rice production. Azolla spp. has also the capacity to take up the heavy metals such as Mercury and Chromium (75${\sim}$100%) and may be used as a bioaccumulator in the phytoremediation. Azolla meal also can be used as an unconventional feed resource has a potential as a feedstuff for livestock.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2296-2302
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• 2018

Internally plasticized PVC was prepared via chemical reaction of azide PVC and alkynyl group containing castor oil methyl ester. The chemical structure of alkynyl group containing castor oil methyl ester and internally plasticized PVC was characterized with FT-IR and $^1H$ NMR. Properties of internally plasticized PVC, including thermal stability, tensile tests and resistance to extraction in different solvents, was investigated. The results showed that alkynyl group containing castor oil methyl ester, as internal plasticizer of PVC, not only decreased the $T_g$ of PVC from $84.6^{\circ}C$ to $41.6^{\circ}C$ efficiently, but also presented no plasticizer loss in five different solvents. The tensile tests showed that elongation at break and tensile strength of internally plasticized PVC was 353.8% and 18.1 MPa. The internally plasticized PVC has potential application in replacing the traditional PVC material in PVC products with high durability.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.99-105
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• 2023

Recently, 2D materials greatly impact in the various applications especially in the energy conversion and storage devices. Among the 2D materials, nowadays researchers are showing their propensity towards the MXenes due to their potential structural and physical properties as well as their use in various applications. Recently, MXenes have been used as filler in polymer electrolytes membranes and as catalytic support to increase the performance of fuel cells (FCs). But this review covers only recent progress and application of MXenes in proton and anion exchange membranes for FCs. Also, this review will provide a significant guidance and broad overview for future research in MXenes based polymer electrolyte membrane for FCs.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.201-213
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• 2022

Creation and administration of green space are emphasized to solve the environmental problem and the management of green space in urban area. Urban area with high development pressure faces green space fragmentation, so the planned approach is needed to improve the continuity of green space. However, the current institutional green axis, used to enhance continuity of urban space is merely an abstract concept under the master plan so that is not a consistent framework for urban green continuity providing no detailed information such as position and path. Therefore, in order to consistently manage green space in continuous point of view, it is insufficient not being connected to each individual green space development projects. This study proposes a method for finding the connection path to enhance urban green space continuity. This proposed method consists of two phases. First phase is finding nodes to connect current green space and second is to calculate the least cost path. We calculate connection cost using NDMI (Normalized Difference Moisture Index), impervious ratio and official land cost, applying to Suwon city and potential greening site that was planned in official master plan. According to the results, we confirm a possibility of finding a cost-effective connection path with detailed spatial information instead of unrealistic abstract concepts and discuss worth applying to a legally plan and policy.

• Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.15.1-15.14
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• 2020

Background: Large rivers are ecological treasures with high human value, but most have experienced decades of degradation from industrial and municipal sewage, row-crop agricultural practices, and hydrologic alteration. We reviewed published analyses of long-term fish diversity publications from three intensively managed large river ecosystems to demonstrate the conservation potential of large river ecosystems. Results: We show how the incorporation of recent advances in river concepts will allow a better understanding of river ecosystem functioning and conservation. Lastly, we focus on the Wabash River ecosystem based on high conservation value and provide a list of actions to maintain and support the ecosystem. In the Wabash River, there were originally 66 species of freshwater mussels, but now only 30 species with reproducing populations remain. Although there were multiple stressors over the last century, the largest change in Wabash River fish biodiversity was associated with rapid increases in municipal nutrient loading and invasive bigheaded carps. Conclusions: Like similarly neglected large river systems worldwide, the Wabash River has a surprising amount of ecological resilience and recovery. For instance, of the 151 native fish species found in the 1800s, only three species have experienced local extinctions, making the modern assemblage more intact than many comparable rivers in the Mississippi River basin. However, not all the changes are positive or support the idea of recovery. Primary production underpins the productivity of these ecosystems, and the Wabash River phytoplankton assemblages shifted from high-quality green algae in the 1970s to lower less nutritional blue-green algae as nutrient and invasive species have recently increased. Our recommendations for the Wabash River and other altered rivers include the restoration of natural hydrology for the mainstem and tributaries, nutrient reductions, mechanisms to restore historical hydrologic patterns, additional sediment controls, and improved local hydraulics.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.479-482
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• 2005

The nutritional worth of Sarson Saag Waste (SSW), a cannery waste, was assessed in comparison with conventional complete diet as a total mixed ration (TMR), and a conventional green fodder, Avena sativa. Each diet was offered ad libitum, supplemented with mineral mixture and common salt, to 4 male murrah buffaloes. The control TMR was made iso-nitrogenous to SSW. Simultaneously, each diet was offered to 3 rumen fistulated male buffaloes for assessing the biochemical changes in the rumen. The nutrient digestibility of unconventional SSW was comparable to that of conventional green fodder-A. sativa but significantly (p<0.05) higher than that of control TMR. The tri-chloro acetic acid (TCA) precipitable-N in the strained rumen liquor of animals fed SSW was considerably higher than that of animals fed A.sativa. The urinary excretion of total purine derivatives was comparable in animals fed SSW and conventional green fodder but significantly (p<0.05) higher than those fed conventional control TMR. The significantly (p<0.05) lower purine nitrogen index (PNI) in animals fed control TMR resulted in significantly (p<0.05) lower microbial protein synthesis than that in animals fed SSW and conventional green fodder. The N-excretion as per cent of nitrogen intake was significantly (p<0.05) lower in animals fed SSW as compared to either of the conventional feeds tested, resulting in significantly (p<0.05) higher Nretention and apparent biological value. SSW supplemented with mineral mixture could serve as an excellent source of nutrients for ruminants.