• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.157-162
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• 1987

The study was carried out to investigate the effects of light intensity, temperature and seasonal trends on the photosynthesis as well as the physiological characteristics of Panax species and cultivars. Four-year-old plant of Violet-stem variant, Yellow-berry variant, Mimaki and Russian ginseng of Panax ginseng C. A. Meyer and American ginseng of Panax quiquefolium L. were used for study. These Panax species and cultivars were cultivated under the straw shading. The light saturation point of leaves in Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 15,000 lux, but that of Russian ginseng was 10,000 lux. The optimum air temperature on the phtosynthesis of Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 20$^{\circ}C$ but that of Russian ginseng was 15$^{\circ}C$ under 15,000 lux. The photosynthetic rates were increased in order of Russian ginseng, Mimaki, Yellow-berry variant, Violet-stem variant and American ginseng. The respiration rates of ginseng leaves were increased according to the increasing of temperature, but it was not different among Panax species and cultivars. Stomata frequency of American ginseng was highest, that of Russian ginseng lowest, while the length of stomata was reverse. The total chlorophyll content of American ginseng and specific leaf weight of Mimaki were higher than other ginseng cultivars. The root weight of American ginseng was heavier than others, but that of Russian ginseng was lighter. The num ber of leaflets per plant of 2-year-old plant and the root weight of 6-year-old plant were increased in order of Russian ginseng, American ginseng, Mimaki, Yellow-berry variant and Violet-stem variant.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.79-89
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• 2012

This study was conducted to investigate the chlorophyll contents, photosynthetic characteristics, chlorophyll fluorescence, and growth performance of Parasenecio firmus under changing light environment. Parasenecio firmus was grown under non-treated (full sunlight) and three different shading conditions (88~93%, 65~75% and 45%~55% of full sunlight) for the experiment. Total chlorophyll content, photochemical efficiency (Fv/Fm), T/R ratio, specific leaf area (SLA), leaf area ratio (LAR), and leaf weight ratio (LWR) were increased with increasing shading level, but decreased dark respiration. Therefore, light absorption and light utilization efficiency were improved under the low intensity light. Plants under 65~75% of full sunlight had best maximum photosynthetic rate and net apparent quantum yield in May. On the other hand, the non-treated plants had lower maximum photosynthetic rate, photochemical efficiency, and chlorophyll content than the treated ones. Parasenecio firmus considered to be a sciophyte, is fairly sensitive to high intensity light. If 88-93% of full sunlight lasts for a long period, photosynthetic capacity will be sharply decreased, though limiting light. These results suggest that growth of Parasenecio firmus adapted to 65~75% of full sunlight.

• Journal of Ginseng Research
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• v.26 no.2
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• pp.85-88
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• 2002

This study was carried out to obtain information of the photosynthetic rate at various temperature and light intensity, stomata, chlorophyll, specific leaf weight, characteristics of aerial part and root in ginseng new cultivars developed by pure line selection. The light saturation point of leaves in new cultivars and Jakyungjong were 15,000 lux, and the optimum air temperature on the photosynthesis of new cultivars and Jakyungjong were 20$\^{C}$. The photosynthetic rates were increased in order of Jakyungjong, Gopoong, Chunpoong and Yunpoong. The dark respiration rate of leaves in ginseng cultivars were increased according to the increasing of temperature, and the dark respiration rate of leaves of Yunpoong was the highest among cultivars. The specific leaf weight (SLW) were increased in order of Jakyungjong, Yunpoong, Gopoong, Chunpoong, but total chlorophyll contents were not different among cultivars. Stomata frequency of Yunpoong was the highest being 69.2ea among cultivars, while the length of stomata was reverse. Yunpoong was superior in aerial part among ginseng cultivars : the number of stem was 1.8ea, the number of palmately leaves was 7.7ea, the number of leaflets was 41.0ea, leaf area was 12.3 dm$^2$ The root weight were increased in order of Jakyungjong, Gopoong, Chunpoong and Yunpoong. Chunpoong and Gopoong hove good root shape the length of tap root in Chunpoong and Gopoong were the longest being 6.5 cm and 6.8 cm respectively, but that in Yunpoong was the shortest being 4.4 cm.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.327-330
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• 2003

The denitrification characteristics of free- and gel- D photosynthetic bacteria were studied. At various salt concentrations (0, 1, 2, 3.5%), the maximum specific growth rates were found to be 0.22, 0.22, 0.20 and 0.11 $h^{-1}$, respectively. At lower pH, pH affected the growth significantly. In experiments of PVA beads, the maximum $N_2$ production rate $(dN_2/dt)$ were calculated to be 0.09-0.10 (D= 0.7cm) and 0.09-0.11(D= 1.0cm) ml/h, respectively, and those per bead were 5 and $5.5\;{\mu}l$/h/bead.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.63-68
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• 2018

This paper presents an integrated photochemical reaction system (i.e., an artificial leaf) that uses earth-abundant catalysts for artificial photosynthesis with a carbon dioxide ($CO_2$) fixation process. The performance of the system was investigated in terms of the energy capture and conversion capabilities. A wireless configuration was achieved by directly doping cobalt oxide as an oxygen-evolving catalyst for water splitting reaction on the illuminated surface of photovoltaic (PV) cell, as well as molybdenum disulfide ($MoS_2$) as an efficient catalyst for $CO_2$ reduction on the back substrate surfaces of the PV cell. The system produces hydrogen and carbon monoxide (CO) as sustainable fuels (i.e., synthesis gas) at around 4.5% efficiency, which implies more than 75% catalytic efficiency at the cathode. The process of solar-driven $CO_2$ conversion and water-splitting reaction is contained in one system, which is one step closer to the successful realization of artificial photosynthesis.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.357-361
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• 2007

Six research areas - Hongcheon, Sangju, Jinan, Punggi, Hamyang and aricultural ginseng field near Sangju- were selected to compare microenvironments and photosynthetic capacity. Monthly mean temperature, precipitation and number of hours of clean days have to be identified because these factors are strongly related to the growth and photosynthesis of forest ginseng. Generally, monthly mean temperature in Sangju was highest at June. Monthly mean precipitation in Hongcheon was higher than other areas. In addition, numbers of clean days in Punggi were highest on May and June. Obviously, photosynthetic capacity of younger age class of forest ginseng grown in every 5 places are getting decreasing when forest ginseng becoming olds.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.221-228
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• 1999

This study measured the seasonal changes in physiological characteristics and antioxidants of Alnus firma to compare several enzyme activities(Rubisco, Superoxide dismutase(SOD) and Glutathione Reductase(GR)) between resistant and sensitive Alnus firma trees. Resistant and sensitive Alnus firma individuals near Yochon industrial complex were selected to conduct this study in 1997. Photosynthetic capacity, stomatal conductance, transpiration, Rubisco, SOD and GR activities of resistant trees which had no visible damages to air pollution were higher than those of sensitive trees in same area. All physiological results supported that biochemical process to be one of the important key features to understand resistance to air pollution. Increases of photosynthetic capacity and antioxidant enzyme activity in resistant trees in response to air pollution were the results of biological compensation to stress.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.19
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• pp.25-31
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• 1975

In order to increase the rate of ripening during the grain-forming stage the partial dressing was introduced with the ordinary dressing comparatively. Two different rice varieties, Bong-kwang(early) and Nong-kwang (moderate), grown at the fine sand alluvial soil of River, Han Kimpo, were investigated. To evaluate the photosynthetic ability of these treatments assimilation rate of Carbon-14 was effectively carried out with the active leaves of rice at the maturing stage, and the inorganic constituents of leaves, stem, leaf sheath and grain were analyzed. All the data on the photosynthetic ability, inorganic constituent and yield determining were discussed with the point of continual phloem translocation between those plant organs.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.561-566
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• 1997

Screening, Identification and some cultural characteristics of ALA$({\delta}-aminolevulinic\;acid)$-producing photosynthetic bacteria were carried out for the optimal production of ALA, one of the bioherbicides. Among photosynthetic bacteria isolated from soil, marsh, pond, etc., KK-10 was the best producer of ALA and identified to be Rhodobacter capsulatus belonging to a typical group of nonsulfur purple bacteria. By addition of 15 mM LA (levulinic acid), an inhibitor of ALA dehydrase in cyclic tetrapyrrole biosynthesis, into culture broth at middle log phase of cell growths, ALA production was considerably increased to about 20-fold (28 mg/l). The combined supplementation of glycine and succinate, each with a concentration of 30 mM also enhanced production of ALA and activity of ALA synthase to about 50-fold (73 mg/l) and 2-fold, respectively. The isolated strain was able to produce upto 80 mg/l under the cultural condition optimized by addition 15 mM LA into the synthetic medium at four different points starting middle log phase.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.195-199
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• 1995

This study was conducted to investigate the Net photosynthesis and respiration rates among the varieties of Soybean(Eunha, Pangsa and Paldal that have high yields) at various leaf temperature and light intensity at the stage of $V_5$. The relations between the Net photosynthesis rate and SLW(specific leaf weight) and chlorophyll content were also investigated. 1. Net photosynthesis rates at $25^{\circ}C$ were $21.5mgdm^{-2}h^{-1}$ in cv. Eunha, $20.2mgdm^{-2}h^{-1}$ in cv. Pangsa and $18.5mgdm^{-2}h^{-1}$ in cv. Paldal. 2. Most cultivars of Soybean showed the maximum rates of Net photosynthesis at $25^{\circ}C$, especially in cv. Eunha. Also Net photosynthesis rates differed depending on the leaf shape. Long leaf shape(cv. Eunha) was better than round leaf shape(cv. Paldal) in Net photosynthesis rate. 3. Respiration rates of leaves in Eunha, Pangse and Paldal were $0.56mgdm^{-2}h^{-1}$ at $15^{\circ}C$, $0.79mgdm^{-2}h^{-1}$ at $20^{\circ}C$ $1.15mgdm^{-2}h^{-1}$ at $25^{\circ}C$ and $1.37mgdm^{-2}h^{-1}$ at $30^{\circ}C$. 4. Specific leaf weight were $3.1mg/cm^2$ in Pangsa, $3.5mg/cm^2$ in Eunha and Paldal. No signlficant difference were showed in net photosynthesis rates and specific lear weight. 5. Leaf chlorophyll content were $2.48{\mu}g/gF.W.$ in Eunha, $2.19{\mu}g/gF.W.$ in Pangsa and $1.67{\mu}/g F.W.$ in Paldal. Significant difference were showed in Net photosynthesis rates and Leaf chlorophyll content. 6. The estimated compensation points at which net photosynthesis approached zero were $10{\mu}Em^{-2}s^{-1}$ in Eunha, Pangsa, and Palda at 1$5^{\circ}C$. The compensation point in cv. Eunha at $20^{\circ}C$ was $12P{\mu}Em^{-2}s{-1}$ while $13{\mu}Em^{-2}s{-1}$ in Pangsa and Palda. The compensation point in cv. Paldal at $25^{\circ}C$ was $18{\mu}Em^{-2}s{-1}$ while $16{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa. The compensation point in cv. Palda at $30^{\circ}C$ was $23{\mu}Em^{-2}s{-1}$ Palda while $13{\mu}Em^{-2}s{-1}$ in Eunha and Pangsa.