• Applied Microscopy
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• v.39 no.4
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• pp.291-299
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• 2009

We report on a quantitative analysis of cone and rod photoreceptors in hamster retina. Cone and rod photoreceptors were counted in retinal whole mounts using differential interference contrast (DIC) optics microscopy after staining of cone photoreceptors were stained with peroxidase-labeled peanut lectin. Middle-to-long-wave-sensitive-(M/L-), and shortwave-sensitive-(S-) cone opsins were visualized by observed using confocal microscope after immunocytochemical procedure. The average cone density was 9,307 $cells/mm^2$, giving a total of cones of 293,060 cone cells per retina. The peak density of cone cells (12,857 $cells/mm^2$) was found 0.3 mm from the optic disk (OD) of the nasal retina. The average rod density was 300,082 $cells/mm^2$, giving a total number of rods of 9,448,150 cells. The peak density of rod cells was found 0.3 mm from the OD of the dorsal retina. Of all photoreceptors studied, the total percentage of rods and cones were 96.99% and cones 3.01%, respectively. The mean ratio of rod and cone was 32.24 : 1. The cone photoreceptors of hamster contained both M/L- and S-cone opsins. The present results suggest that the hamster retina is strongly rod-dominated with some photopic property of vision.

• Solar Energy
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• v.13 no.1
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• pp.49-58
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• 1993

[ $CdS_{0.46}Se_{0.54}$ ] single crystal was grown by a sublimation method. The crystal structure and the temperature dependence of carrier density and mobility of $CdS_{0.46}Se_{0.54}$ single crystal were studied. Heterojunction solar cells of $n-CdS_{0.46}Se_{0.54}/p-Cu_{2-X}S_{0.46}Se_{0.54}$ were fabricated by the substitution reaction. The spectral response, the J-V characteristics and the conversion efficiency of the $n-CdS_{0.46}Se_{0.54}/p-Cu_{2-X}S_{0.46}Se_{0.54}$ heterojunction solar cells were studied. The open-circuit voltage, short-circuit density, fill factor and conversion efficiency of $n-CdS_{0.46}Se_{0.54}/p-Cu_{2-X}S_{0.46}Se_{0.54}$ heterojunction solar cells under $80mW/cm^2$ illumination were found to be 0.48V, $21mA/cm^2$, 0.75 and 9.5%, respectively.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.1-11
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• 2018

We studied natural and plantation forest ecosystem of Sarguja in Chhattisgarh, India in order to understand how vegetation biomass, carbon stock and its allocation patterns vary among the sites. For this, stratified random sampling was opted to measure the different layers of vegetation. Wide floral diversity was found in the natural forest site as compared to the teak stand. Overall, 17 tree species found in natural forest comprising 8 families while in the teak stand 6 species were recorded. In understory strata 23 species were recorded (18 herbs and 5 shrubs) in natural forest whereas in teak stand 20 herb species and 3 shrubs were found. Great variation was also seen in the population dynamics of the different vegetation stratum in concerned sites. The sapling, seedling and herb density was found to be highest in natural stand while tree and shrub density was more in teak stand. Results indicated that stand biomass of the natural site was $321.19t\;ha^{-1}$ while in the teak stand it was $276.61t\;ha^{-1}$. The total biomass of tree layer in plantation site was $245.22t\;ha^{-1}$ and natural forest $241.44t\;ha^{-1}$. The sapling, seedling, shrub and forest floor biomass was found highest under natural forest as compared to the teak plantation site. Carbon stock has similar trend as that of biomass accumulation in natural forest and teak stand. Higher biomass accumulation and carbon stock were recorded in the higher girth class gradation of the population structure. Proper efforts are required to manage these diverse ecosystems to obtain higher biomass and sustainable ecological services.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.2
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• pp.79-90
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• 1987

This second consecutive research was connected to 7he previous first research with same title. The purpose of this research is to estimate the carrying capacity for the Seonjeong royal tomb and to propose its management planning. User's characteristics and relationship between user's density and vegetational environment were analized for the above objective. The result of this research shall be summarized as follows. 1. The site was damaged seriously by pupils and social groups'picnic activities concentrated in special periods of Friday and weekend during April and May. 2. Social-psychological carrying capacity estimation would be impossible due to lack of relationship between user's density and satisfaction. 3. Maximum user's density limits as a ecological carrying capacity was 1.4 persons per 100 square meters and modified optimum ecological carrying capacity was estimated as 1.0persons per 100 square meters. Maximum visitors as a optimum carrying capacity of the Seonjeong royal tomb area was estimated as 6,000 persons when supposing the proposed landuse planning. 4. To restore and preserve the tomb landscape as a traditional historic site, Seonjeong royal tomb shall be managed by three landuse areas ; protection and control area, natural picnic area and shaded picnic area. And the protection and control area include three sites ; natural reclamation site, natural preservation site and tomb landscape conservation site.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.375-384
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• 1997

The effects of three different irrigating water qualities(clean water, life sewage and animal sewage) on the pattern of arthropod communities in the rice fields were investigated at Banwol, Kyonggi-do, mid-western part of Korea from 1994 to 1996. The total density of arthropod was highest in the rice field which was irrigated with clean water(clean water field), and the arthropod community was mainly composed of aphids and collembolans. Each functional group was found in the order of 'pests>non-pests>natural enemies' in its density. The dominant taxa in the pest group were aphids, planthoppers(Delphacidae), leafhoppers(Cicadelidae) and rice water weevil(L. oryzophilus). In the non-pest group collembolans, non-biting midges and dipterans were main arthropods, and in the natural enemy group Araneae was the dominant taxon. In the early growth stage of rice plant the dominant functional group was pests, and in the mid growth stage both the pest and the natural enemy group became dominant. But in the late growth stage none of the functional group was dominant over the other functional groups. The densities of spiders were much more higher in the clean water field than in the other fields. And through all the growth stages of rice plants the density of spiders in clean water field kept increase in contrast to the others. The species composition of spiders in the life sewage field was similar to that in the animal sewage field, but in the clean water field it was different from the other two fields.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.959-964
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• 2004

A low-dimensional metal frequently exhibits a metal-insulator transition through a charge-density-wave (CDW) or a spin-density-wave (SDW) which accompany it's structural changes. The transition temperature is thought to be determined by the amount of energy produced during the transition process and the softness of the original structure. $AMo_4O_6$ (A=K, Sn) are known to be quasi-one dimensional metals which exhibit metalinsulator transitions. The difference of the transition temperatures between $KMo_4O_6$ and $SnMo_4O_6$ (A=K, Sn) is examined by investigating their electronic and structural properties. Fermi surface nesting area and the lattice softness are the governing factors to determine the metal-insulator transition temperature in $AMo_4O_6$ compounds.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.628-634
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• 2000

Crosslink is the most important chemistry in a rubber vulcanizate. Degree and type of crosslinks of the vulcanizate determine its physical properties. Change of crosslink density and deformation of a rubber vulcanizate by thermal aging were studied using natural rubber (NR) vulcanizates with various cure systems (conventional, semi-EV, and EV) and different cure times (under-, optimum-, and overture). All the NR vulcanizates were deformed by the thermal aging at 60-100 $^{\circ}C.$ The higher the aging temperature is, the more degree of the deformation is. The undercured NR vulcanizates after the thermal aging were deformed more than the optimumand overcured ones. The NR vulcanizates with the EV cure system were less deformed than those with the conventional and semi-EV cure systems. The deformation of the NR vulcanizates was found to be due to change of the crosslink density of the vulcanizates. The crosslink densities of all the vulcanizates after the extraction of organic materials were also changed by the thermal ging. The sources to change the crosslink densities of the vulcanizates by the thermal aging were found to be dissociation of the existing sulfur crosslink and the formation of new crosslinks by free sulfur, reaction products of curing agents, and pendent sulfide groups.

• Fisheries and Aquatic Sciences
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• v.25 no.8
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• pp.409-416
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• 2022

This study aims to know the effect of water-extracted horseradish Moringa oleifera leaf and KW21 fertilizer combination application on the density of Nannochloropsis sp. It was conducted in the Natural Food Laboratory of State Polytechnique, Tual. The experiment used complete randomized design with 5 treatments and 3 replications: A (25% horseradish leaf extract + 75% KW21), B (50% horseradish leaf extract + 50% KW21), C (75% horseradish leaf extract + 25% KW21), D (positive control of 100% KW21), and E (negative control of 100% horseradish leaf extract). Results showed that Treatment C yielded the best result, both the highest density of Nannochloropsis sp. and suitable harvest time.

• International Journal of Concrete Structures and Materials
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• v.8 no.1
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• pp.15-26
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• 2014

In order to study the capacities of a new occurrence of Brazilian clay samples as partial replacements of cement, a bentonite sample was selected for utilization in the natural and modified forms for present study. The natural bentonite (BBT) was modified by anchorament of 3-aminopropyltrietoxisilane ($BBT_{APS}$) and 3,2-aminoethylaminopropyltrimetoxisilane (BBTAEAPS) in the surface of component minerals of bentonite sample. The original and organo-bentonite samples were characterized by elemental analysis, scanning electron microscopic and textural analyses. The values of micropore area were varying from $7.2m^2g^{-1}$ for the BBT to $12.3m^2g^{-1}$ for the $BBT_{AEAPS}$. The bentonite samples were characterized by the main variable proportion of bentonite in the natural and intercalated forms (2, 5, 10, 15, 20, 25, 30, and 35 % by weight of cement) in the replacement mode whiles the amount of cementations material. The workability, density of fresh concrete, and absorption of water decreased as the substitution of ordinary Portland cement by perceptual of natural and modified bentonite increased. The results reveal that workability decreased with decrease of the amount of natural bentonite in the concrete, same behavior is observed for bentonite functionalized, varying from 49 to 28 mm. The energetic influence of the interaction of calcium nitrate in the structure of blends was determined through the calorimetric titration procedure.

• Journal of Environmental Science International
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• v.20 no.6
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• pp.701-710
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• 2011

The purpose of this study is to investigate the vegetation structure and ecological restoration of disturbed forest due to artificial plant. To this end, 12 plots were set up and surveyed. The result analyzed considering mean importance percentage(M.I.P) showed that the types were divided into three groups which are artificial planted forest type(three plots), natural forest-artificial planted forest type(four plots), natural forest type(five plots). Dominant proportion of artificial planted species were as follows: artificial planted forest type was over 60%, natural forest-artificial planted forest types were 14~49%. The range of Shannon's index of all associations was from 0.7131 to 0.7771(natural forest-artificial planted forest > natural forest > artificial planted forest). Also we suggested restoration method of vegetation for ecological value as follow: Control of density considering step and Remove of Pinus koraiensis seedlings of understory layer and shurb layer.