• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.27-45
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• 2017

At the upper part of terrace deposits at Jeongdongjin area, there is a structure in which reddish brown and grayish white layers laying horizontally. Previous studies have reported the existence of these structures within the deposits and suggested the theoretical background related to the formation process. However, the analysis of physical properties and chemical composition such as particle size, classification, etc. of the materials constituting the reddish brown and grayish white layers is scarcely done. In this study, the physico - chemical properties of gray - white and reddish brown beds are investigated. The mean grain size of the particles was less than $4{\varphi}$ in both layers and the reddish brown layer was more coarse. The results shows that the sorting of the grayish white layer is better. The chemical composition of both layers shows that the average concentration of $SiO_2$, $Al_2O_3$ and $K_2O$ of the grayish white layer was higher than those of the reddish brown layer. The concentration of $Fe_2O_3$ of reddish brown lyaer was 3 times higher than those of the grayish white layer. The degree of chemical weathering (CIA) is 90 or so in both the reddish brown and grayish white layers, indicating a significant level of chemical weathering. In conclusion, reddish brown layers had been formed by the processes related to the migration of iron and the migration of water that induced aggregation after the formation of sediments (psudo-gleization). In this study area, a vertical layer of grayish white which cuts off horizontal reddish brown and grayish white color was found. The vertical layer or wedge similar to a ice-wedge or columnar structure that in a cold environment, and there is a difference in shape and size. The vertical layer appears to have occurred three or more cycles. The vertical layers begin to form at a certain height within the outcrop and descend downwards, which of course is difficult to see as directing certain times.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.35-40
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• 2012

In this study, the effect of degree of milled wax layer on compositions (protein and total dietary fiber content), Alkali Digestion Value (ADV), and texture (hardness, stickiness, toughness, and adhesiveness) with brown rice was investigated. For all the rice cultivars, $Baegjinju$, $Keunnun$, $Samkwang$, and $Seolgaeng$, protein content decreased significantly as the degree of pericarp milling increased ($p$<0.05). Total dietary fiber (TDF) content for $Keunnun$ (9.56%${\rightarrow}$8.09%) and $Samkwang$ (8.05%${\rightarrow}$7.06%) significantly decreased with the degree of removed wax layer. ADV was not affected by being removed wax layer, but ADV of $Samkwang$ was increased from 3.56 to 6.78. As the degree of removed wax layer increased (0%${\rightarrow}$10%), hardness and toughness of cooked brown rice were decreased but stickiness and adhesiveness was increased. The ratio of adhesiveness to hardness was increased with decreased wax layer of brown rice. Accordingly, It suggests that the regulation of the wax layer with brown rice was effected texture of cooked brown rice. The milling technology in wax layer of brown rice is that might be thought to be very useful in rice processing industry.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.784-792
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• 1998

This study was conducted to select resistant chicken-line between Brown and White layer lines against Salmonella gallinarum infection. The Brown and White layer chickens allocated into different age groups were inoculated with S gallinarum (WJO-126) either orally($1{\times}10^7cfu$) or intramusculaly($5{\times}10^6cfu$) and clinical observations were made for 2 weeks. All dead birds were necropsied and culture was made to recover the inoculated organinsm from liver, spleen, brain, bone marrow and cecal contents. Serum was isolated from all live birds after 2 weeks experiment and these birds were also necropsied and cultured to reisolate S gallinarum. The brown layers showed very high mortality to S gallinarum infection regardless of their ages and routes of inoculation, while white layers did not shown any mortality by the direct effects of S gallinarum. The mortality rate of 2 week old brown layers, in particular, were 82.6% (19/23) in peroral group and 86.9% in intramuscularly inoculated group, while those of white layer groups were only 0.0% in both groups. S gallinarum could be reisolated from all dead birds, especially, from liver and spleen. This result was inferred that the organism is highly invasive on the chicken. The intramuscularly challenged birds showed more seropositive-reactors(86.9%) than orally inoculated groups(61.9%). The overall results of present study suggested that white layers are much more resistant than brown layers against the experimental infection of S gallinarum and shown experimentally that resistance to S gallinarum is a characteristic of the White-line layers.

• Journal of the Korean Geographical Society
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• v.36 no.3
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• pp.233-246
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• 2001

Topography and soil characteristics of earth hummocks are examined in the summit crater of Mt. Halla in order to evaluate their morphoclimatic significance as an indicator of a periglacial environment. The hummocks are generally oval in outline, and they have a diameter of 42 to 200 cm and a height of 9 to 27 cm Seventeen hummocks are distributed In a 5$\times$5 m quadrat at an interval of 20 to 40 cm Excavation reveals the cryoturbated soil profiles which consist of upper dark brown layer and lower brown layer. The dark brown layer has 61.8% total clay and silt content, implying Its high frost susceptibility Earth hummocks have the dry density of 0.761 to 1.009 g/㎤ the void ratio of 1420 to 2.008, and the moisture content of 24.2 to 68.8% by weight, respectively. The hummocky soils become compacted and desiccated downward. Earth hummocks are frozen as a hard solid mass during winter and early spring, and freezing fronts reach about 45 cm below their apices. The layer with high lute content appears in the upper horizon of dark brown soil. but Ice lenses are not so much segregated The moisture content of hummocky soils generally increases up to 73.9 to 118.80% for dark brown layer and 49.9 to 82.8% for brown layer during thins period Because the cohesive soil of earth hummocks indicates 72.8% of the moisture content as a liquid limit, the dark brown layer is highly fluid and consequently subject to cryoturbation processes.

• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.70-77
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• 2001

A preliminary experiment was conducted to produce fowl-typhoid resistant egg type breeds, using three brown egg layer breeders (ISA, Hyline, and Lohman) and two white egg layer breeders (ISA and Lohman). Various economic parameters were measured from day-old to mature stages using parent stocks of each breed. No significant difference in viabilities of mature hens from 34 to 66 wk of ages was found between brown(93.3%) and white(93.5%) egg layer breeders (P>0.05). Also, there was no difference in viabilities of mature cockerels. Although not significant, the mature body weights of brown egg layer breeders tended to be heavier than those of the white egg layer breeders both in hens and cockerels. No difference in feed intakes of mature brown and white hens were detected. Ages of sexual maturity of white and brown egg layer hens were 147.7 and 140.5 d, respectively (P<0.05). Egg production of white egg layer hens during 23-66 weeks age was significantly higher than their counterpart (81.4% vs. 75.0%). Comparisons of Haugh Unit, egg shape index, yolk color, and egg weight between brown and white eggs were not significantly different; however, the brown eggshells were thicker and stronger than those of white eggs (P<0.05).

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.74-75
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• 2005

In order to evaluate dietary brown seaweed and vancomycin on the performance, layers(Isa brown) were fed on basal diet and diets containing 2.0% of brown seaweed or 10ppm vancomycin. Brown seaweed diet significantly increased(p<0.01) nitrogen balance in layer, while excretion of uric acid nitrogen and metabolizable energy utilization were not different among diets. Layer consumed more the brown seaweed diet(p<0.05). Egg production were significantly different by diets but reduced(p<0.0001) with the experimental period passed. Layer fed brown seaweed diet gave thicker shell eggs, higher Haugh unit and higher egg white CuZnSOD activity compared with those in basal diet. Also, Brown seaweed diet increased MnSOD activity in erythrocyte cytosol and peroxidase in plasma, but decreased peroxide level in plasma, and increased proliferation of PBMC stimulated with PHA-P The result indicated that brown seaweed 2.0% diet in layer improved egg quality and performance due to increased protein synthesis which were related to regulation of antioxidant system and immune cell function in blood.

• Ocean and Polar Research
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• v.28 no.3
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• pp.287-290
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• 2006

Eye growth and lens diameter of brown croaker Miichthys miiuy were positively allometric between hatching and 180 days post-hatch (d.p.h.). Eye growth in relation to head length and head height was nearly isometric. Eyes were formed completely at 14 d.p.h. At this age, the eye has a crystalline lens, an optic nerve fiber layer, a ganglion cell layer, an inner plexiform layer, an inner nuclear layer, an outer plexiform layer, an outer nuclear layer, an outer limiting membrane, and a pigment epithelium. The essential demands that must be met by the retina in this species pertain to light sensitivity and spatial resolution.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.614-619
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• 2012

We investigated color and graphite layer formation on the surface of Type I tinted brown diamonds exposed for 5 minutes under a high-pressure high-temperature (HPHT) condition in a stable graphite regime. We executed the HPHT processes of Process I, varying the temperature from $1600^{\circ}C$ to $2300^{\circ}C$ under 5.2 GPa pressure for 5 minutes, and Process II, varying the pressure from 4.2 to 5.7 GPa at $2150^{\circ}C$ for 5 minutes. Optical microscopy and micro-Raman spectroscopy were used to check the microstructure and surface layer phase evolution. For Process I, we observed a color change to vivid yellow and greenish yellow and the growth of a graphite layer as the temperature increased. For Process II, the graphite layer thickness increased as the pressure decreased. We also confirmed by 531 nm micro-Raman spectroscopy that all diamonds showed a $1440cm^{-1}$ characteristic peak, which remained even after HPHT annealing. The results implied that HPHT-treated colored diamonds can be distinguished from natural stones by checking for the existence of the $1440cm^{-1}$ peak with 531 nm micro-Raman spectroscopy.

• Korean Journal of Environmental Biology
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• v.42 no.2
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• pp.187-192
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• 2024

Pseudolithoderma subextensum is a crustose brown algal species in the family Lithodermataceae and order Sphacelariales. This species is distributed in several regions across the world including, Europe, Western Atlantic, Middle East and Asia (Hong Kong and Japan). Recent floristic surveys along the Korean coastal shores have revealed new records of encrusting brown algae. In this study, we report P. subextensum as a new record from Korea. Morpho-anatomical and molecular studies on Ralfsia-like specimens from Korea identified some of them as P. subextensum. Pseudolithoderma subextensum is characterized by dark chestnut brown crust with a hypothallial basal layer and erect perithallial filaments, tufts of hairs occasionally arising from the basal layer, several discoid shaped chloroplasts per cell, plurangia arising terminally on erect filaments and without sterile cells, and unangia arising terminally on erect filaments, elongated cylindrical and without paraphyses. Phylogenetic analyses based on COI-5P (545bp) reveal that P. subextensum are nested within Lithodermataceae and forms the same clade with P. roscoffense. The genetic divergences for COI-5P between them is 24.5%.

• Journal of the Korean earth science society
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• v.33 no.4
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• pp.320-328
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• 2012

To investigate geomorphic development of alluvial plains and climatic environment change during the late Holocene carbon dating, soil organic carbon analysis and humus analysis of sediments from alluvial plain of Hampyeongcheon basin were performed. The lowest peat layer was formed under warm and humid climates, which is considered to correspond to the Atlantic period in the Holocene. Yellowish brown sandy clay layer was deposited in the natural levee, which we think were deposited in the generally warm and dry climates. The carbon dating age is 1,879-1,532 BC, and this period correspond to the Sub-boreal period in the Holocene. Light brown clay layer is assumed to have been deposited in transitional environment from the natural levee to the back marsh. The climatic environment was warm and humid, which is considered as transitional period from the Sub-boreal to the Sub-Atlantic in the Holocene. Light yellowish brown and light brown clay layer of the upper part are regarded as sediments of the back marsh. Light yellowish brown clay layer was deposited in the cold and dry climates, which is considered to correspond to the Sub-Atlantic period in the Holocene. Light brown clay layer was deposited in the warm and dry climates. The carbon dating age is 211-427 AD, this period corresponds to the Post Roman Warm Period in the Holocene.