• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.19-26
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• 2017

Increasing global energy demand has resulted in an energy crisis. The dye sensitizer solar cell (DSSC) is an alternative source because of its ability to convert the sun's energy into electrical energy. Our aim was to determine the effect of synthesized Ni(II)-Chlorophyll for enhancing the efficiency of solar cells based DSSC. Complex compound Ni(II)-Chlorophyll was successfully synthesized as a dye sensitizer of $Ni(NO_3)_2.6H_2O$ and chlorophyll ligand with saponification method. Characterization results with spectrophotometer UV-Vis showed that the complex compounds of Ni(II)-Chlorophyll have a maximum wavelength of 295.00 nm, 451.00 and 665.00 nm. The bond between the ligand and metal appears in the vibration Ni-O at wave number $455.2cm^{-1}$. Complex compoun Ni(II)-Chlorophyll has a magnetic moment 7.10 Bohr Magneton (BM). The performance of complex compound Ni(II)-Chlorophyll as a dye sensitizer shows the value of short-circuit current (Jsc) at $3.00mA/cm^2$, open circuit voltage (Voc) at 0.15 V and the efficiency (${\eta}$) 0.20%.

• Membrane and Water Treatment
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• v.10 no.1
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• pp.39-44
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• 2019

LID facilities do not consider environmental factors, and due to inappropriate vegetation planting causing degradation in efficiency due to plant damage and difficulty in maintenance. Therefore, in this study, assessment of impact environmental factor by seasonal variation of chlorophyll and growth of vegetation planted in LID technologies and change of pollutant reduction were conducted. In the case of B-SJ and B-RI, growth rate decreased after summer (August), and B-MG showed steady growth until autumn (September). Chlorophyll was found to increase during spring season while it decreased during autumn season. The chlorophyll concentration was found to affect the plant growth pattern. TN reduction efficiency was highest with greater than 80% efficiency in summer, and it was analyzed that plants were identified as the main factor affecting the seasonal reduction efficiency of TN. Also, temperature and relative humidity were analyzed to affect plant growth, activity and pollutant removal efficiency. Plant type and growth pattern are considered as factors to be considered in selection of appropriate plant types in LID technologies.

• Journal of Life Science
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• v.32 no.10
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• pp.743-748
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• 2022

The garlic chive (Allium tuberosum Rotter) is a prominent herb species in Asia and other nations of the world. Garlic chives is a favorite vegetable and used to garnish noodles in Korea. The effects of various doses of N, P, and K fertilizers and drought stress on the chlorophyll content in the leaves of garlic chives were investigated. The evaluations showed that chlorophyll a content was 0.386 at 10 mg/l N fertilizer and 0.584 at 50 mg/l N fertilizer. The treatment group showed a significant difference with regard to the contents of chlorophylls a and b and total chlorophyll at the 5% level (p<0.05). Pearson's correlation coefficient (Pearson's r) for chlorophylls a and b and total chlorophyll were 0.940, 0.966, and 0.971, respectively. The highest content of chlorophylls a and b and total chlorophyll in the leaves was recorded at 40 mg/l P fertilizer, while the values corresponding to 50 mg/l P fertilizer were lower than those for 40 mg/l P fertilizer. The content of total chlorophyll evaluated at 10 mg/l K fertilizer was 0.312 and that at 50 mg/l was 0.589. The simple linear regression showed the relationship between chlorophyll efficiency aand moisture. The slope factors of the dark-level fluorescence yield (Fo), the maximum fluorescence yield (Fm), the quenched state (Fv), and the maximal PSII quantum yield (Fv/Fm) for chlorophyll-efficient indicators were -0.931, 0.972, 972, and 0.950, respectively. NPK fertilizers and drought stress affected the chlorophyll content and efficiency of A. tuberosum.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.485-489
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• 2008

Algal chlorophyll-$\alpha$ is commonly determined by spectro-photometric method using 90% acetone as solvents. However, acetone has low extraction efficiency without grinding filters, and DMF (dimethyl formamide) was tested for the compatibility with acetone. Chlorophyll-$\alpha$ concentration was determined for samples from 5 reservoirs of different trophic states and phytoplankton composition, using acetone extraction with grinding and DMF without grinding. Chlorophyll-$\alpha$ measured by DMF and Acetone did not show a significant difference when using trichromatic method of UNESCO and Lorenzen, and therefore, DMF can substitute acetone. But when acidification method was applied, they showed significant difference of 8%. It can be concluded that DMF can extract chlorophylls more effectively without grinding and it can be a better alternative for the standard extraction solvent.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.320-330
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• 2012

This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.153-161
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• 2012

This study was conducted to investigate the chlorophyll contents, photosynthetic characteristics and chlorophyll fluorescence of Cirsium setidens and Pleurospermum camtschaticum by shading treatment. Two species were grown under non-treated (full sunlight) and three different shading condition (88~93%, 65~75% and 45%~55% of full sunlight) for the experiment. Total chlorophyll content, photochemical efficiency (Fv/Fm), specific leaf area (SLA), and net apparent quantum yield were increased with elevating shading level but decreased dark respiration under the low light intensity. Therefore, light absorption and light utilization efficiency were improved under the low light intensity. 45~55% of full sunlight in C. setidens and 65~75% of full sunlight in P. camtschaticum showed best maximum photosynthetic rate, net apparent quantum yield and photochemical efficiency. On the other hand, non-treated showed lower maximum photosynthetic rate, photochemical efficiency, and chlorophyll content than treated ones. These results suggest that growth of P. camtschaticum adapted to 65~75% of full sunlight and C. setidens adapted to 45~55% of full sunlight.

• ALGAE
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• v.25 no.2
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• pp.89-97
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• 2010

To test the feasibility of using chlorophyll ${\alpha}$ fluorescence to assess the establishment success of seagrass transplants, photosynthetic characteristics of eelgrass Zostera marina transplants were measured using a Diving-pulsed amplitude modulation fluorometer in Jindong Bay on the southern coast of Korea. Maximum quantum yield ($F_v/F_m$), photosynthetic efficiency ($\alpha$), saturating irradiance ($E_k$) and maximum electron transport rate ($ETR_{max}$) of transplants and reference plants in a nearby transplant site were measured using the fluorometer for 5 months. Additionally, shoot morphology, individual shoot weight and productivity of transplants and reference plants were also monitored. Shoot height, leaf weight and productivity of transplants were significantly reduced during the first two or three months after transplantation compared to those of reference plants, and then increased to the levels of reference plants Characteristics of chlorophyll a fluorescence, including $F_v/F_m$, $\alpha$, $E_k$ and $ETR_{max}$ of transplants were also significantly reduced in the initial period, but recovered slightly sooner than shoot morphology or leaf productivity. These results indicated that after transplantation, Z. marina transplant photosynthesis recovered faster than shoot morphology, biomass or productivity. Thus, chlorophyll a fluorescence can be used as an indicator for early assessment of the status of eelgrass transplants without destructive sampling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.89-93
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• 2004

This experiment was conducted to investigate the variation of nitrogen use efficiency, nitrogen uptake efficiency, physiological utilization efficiency and their relationships with growth characteristics in the 28 Korean rice cultivars. Nitrogen use efficiency of 28 rice cultivars was 47.74, nitrogen uptake efficiency was 0.71, and physiological utilization efficiency was 68.76 in average. Nitrogen use efficiency of rice cultivars had low variation ranged from 44.09 to 51.91, but nitrogen uptake efficiency were relatively high variation from 0.51 to 0.90, and physiological utilization efficiency was from 51.71 to 94.26. The high efficient group in nitrogen uptake efficiency whose value was calculated above 0.80 included Daeanbyeo, Seojinbyeo, Ansungbyeo, Dongjinbyeo, and Hwaanbyeo, while the low efficient group with below 0.60 was Kwanganbyeo, Sampyeongbyeo, Soorabyeo, and Hwasungbyeo. Hwasungbyeo, Sampyeongbyeo, Soorabyeo for physiological utilization efficiency were more efficient cultivars, while Daeanbyeo, Seojinbyeo, Ansungbyeo were less efficient cultivars. Nitrogen uptake efficiency had positive correlation coefficients between dry matter weight of plant ($0.842^{**}$), leaf area index ($0.761^{**}$), and leaf nitrogen content ($0.599^{**}$), respectively. Therefore, the dry matter weight of rice plant and leaf area index was important characters to evaluate nitrogen uptake efficiency in rice cultivars. Also, more efficient cultivar in nitrogen uptake had higher chlorophyll meter value, which was appeared dark green color.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.88-94
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• 2011

This study was conducted to provide on a basic information for maintenance of roadside trees and identify the links between environmental pollution and tree damages (Ginkgo biloba, Platanus occidentalis) in Daejeon City by analyzing photosynthetic characteristics, water use efficiency, chlorophyll fluorescence and chlorophyll contents by the regions and plants. The investigations were conducted at Chungnam national university(CNU) considered as the least air-polluted area compared to other study sites, Daedeok science town(DS) which a new road with little traffic recently was built around, Daehwa industry complex(DIC) and Daejeon station(DS) which an old road with heavy is located around. The photosynthetic capacity of the two species were highest in CNU and lowest in the DS. However the water use efficiency was highest on the contrary to the photosynthetic capacity in DS. Chlorophyll fluorescence and chlorophyll contents were highest in CNU and lowest in DS as the photosynthetic capacity. On all of the test, Ginkgo biloba shows the more favorable physiological responses than Platanus occidentalis.

• Journal of Korean Society on Water Environment
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• v.25 no.6
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• pp.832-839
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• 2009

Since construction of the estuarine barrage at the mouth of the Nakdong River, eutrophication and increased abundance of phytoplankton have occurred mainly due to the increased retention time in the reach. However, during the spring, there is a decrease in chlorophyll-a, as a result of an increase in zooplankton number, which preys upon phytoplankton and affects the value of chlorophyll-a. In order to emphasize the importance of zooplankton data in water quality simulation, zooplankton community data were used to simulate water quality and eutrophication at Mulgeum located in 27 km upstream from the barrage. WASP 7.2 was used as the water quality model for the river, using a monthly data set from 2003 to 2005 for model calibration and verification. The results showed that chlorophyll-a, DO, and total nitrogen in the river were simulated well during the verification period. The results of water quality simulation using zooplankton community data in the model were better than those with phytoplankton death rate, in terms of the absolute value of percent bias, root mean square error, and Nash-Sutcliffe efficiency. Those results indicate the use of zooplankton data provides more accurate simulation results for chlorophyll-a and eutrophication.