• The Korean Journal of Malacology
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• v.32 no.1
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• pp.25-30
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• 2016

Growth-line analysis was carried out on 80 hard clam (Meretrix petechialis) from the Neolithic Age Eurwang-dong Shell Midden, Incheon, Korea, to determine the seasonality of shellfish collection and site occupation. Growth increments and the marginal index (MI) of the specimens were examined. And then the marginal index was compared to the monthly MI of modern specimens under the assumption that the growth pattern was the same as it is today. MI of the archaeological specimens ranged from 0.12 to 1.55 and was divided into four categories: < 0.63, spring; 0.63-0.76, summer; 0.76-0.89, fall; $${\geq}_-0.89$$, winter collection. As a result, 57 specimens (71.25%) of 80 specimens represented spring, 8 (10.0%) summer, 3 (3.75%) fall and 12 (15.0%) winter collection. The result indicates that shellfish could be collected year-round at the site with an emphasis on spring. Based on the size distribution of shells and the content of the midden, however, it seems that the midden site was not occupied permanently throughout the year but was used repeatedly but temporally for shellfish gathering and processing.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.185-190
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• 2005

An experiment was conducted to know the effects of crab shell, sericite ore, and charcoal powders on the growth, yield, and grain quality of rice. After application of 110-40-57 kg/ha of $N-P_2O_5-K_2O$, 3,000 kg/ha of crab shell and charcoal powders and 5,000 kg/ha of sericite ore powder were applied and incorporated into soil before transplanting of rice seedlings. The number of tillers and panicles, leaf area index at heading stage, N concentration of plants, and protein content and chalkiness of rice grains were increased with the application of crab shell powder, while the percentage of ripened stains and head rice and Toyo taste value were decreased. The yield of milled rice and other grain appearance and chemical and physical properties of rice grains were not affected by the application of crab shell powder. The sericite ore and charcoal powders increased protein content decreased Toyo taste value, but did not affect on the growth, yield and yield components and other grain qualities.

• Journal of Aquaculture
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• v.11 no.2
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• pp.193-201
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• 1998

This study was carried out to investigate the enviromental quality and the growth of transplanted pen shell, Atrinna pectinata japonica. Followings are the results of growth of transplanted pen shell with respect to the shell size groups from the natural habitat (Usando) in May 1995, and cultivated upto November in the transplantated area (Soomoonri). The water depth of transplantated area andnatural habitat were 3m, 20~25m, respectively. The seawater temperature of the two culturing farms were ranged of 10.9~$27.8^{\circ}C.$, 8.5~$30.0^{\circ}C.$, respectively at the lowest in November adn the highest in July. The seawater salinity of the two areas were ranged of 29.54~35.26$^0\prime\infty$, 28.75~36.31$^0\prime\infty$, respectively at the lowest in July and the highest in November. The phosphoric acid ($PO_4$-P) of the two areas were 0.09~$1.14 ^{\mu}$g-at/l, 0.23~$1.33 ^{\mu}$g-at/l, respectively at the lowest in June and the highest in September. The bottom type of the two areas was a silty mud, 85.23% (82.17~87.26%) in natural habitat and 92.12% (90.76~92.94$^0\prime\infty$) in transplanted area. In this study area, phytoplankton were composed of 19 species. Of these 19 species, Skeletonema costatum was dominant species in seawater between natural habitat and transplantatied area, and 157 cells/ml, 165 cells/ml at August respectively. Stock of phytoplankton in transplantated area were more than those of natural habitat except June and November. The growth of shell length, shell height, total weight, soft part weight and posterior adductor muscle weight of pen shell on different size groups (SL 10, 10~15, 15~20, 20cm) were excellent in shell length of 10cm group, and 99.32%, 107.66%, 871.09%, 951.26% and 1,223.76%, respectively. The survival rate of pen shell was 98.10% in the shell length of 10cm groups, 90.35~94.76% in the others groups. The growth of shell length, total weight, soft part weight and posterior adductor muscle weight of pen shell in transplantated area were more 1.3, 2.6, 2.7 and 4.5 times than those of natural habitat.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.9-16
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• 2007

Data obtained from field observation revealed that the degree of shell bioerosion of the scallop, Patinopecten (Mizuhopecten) yessoensis, by endolithic organisms significantly higher on the muddy sand than on the sand. At the area studied, the polychaete worm, Polydora brevipalpa (=Polydora ciliata brevipalpa, Polydora ciliata Okuda, Not Johnston, Polydora variegata), which is common symbiotic species for the scallop made 95-100% of total scallop shell bioerosion at the area studied. The muddy bottom sediments enriched by organic matter create favourable conditions for development of microphytobenthos and bacteria, which are predominantly consumed by P. brevipalpa. Linear regressions for the degree of shell bioerosion on the scallop shell height, total wet weight and adductor muscle wet weight revealed negative relationships between them for the scallops inhabiting both sand and muddy sand. The influence of polychaetes on scallops is complex. They may be food competitors. Polychaete can directly affect the host through their boreholes. Scallop expends energy for shell regeneration to prevent the polychaete penetration into its interior cavity. It was found that the degree of shell bioerosion increased considerably with scallop age.

• The Korean Journal of Malacology
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• v.19 no.2
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• pp.125-132
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• 2003

Age and growth of the the Jedo venus clam, Protothaca jedoensis were investigated using samples from the subtidal zone of Boryeong, Chungcheongnam- do, Korea from January to December, 1999. The relationship between shell height and ring radius in each group was expressed as a regression line. Therefore, it could be recognized that there is a correspondence in the formation of each ring. Based on the monthly variation of the marginal index of the shell, it was suggested that the annual ring mark formation occurred during the period of February to March once a year. The relationship between shell height (SH) and total weight (TW) was represented by the non-linear equation: TW = 0.0007 SH$^{2.8919}$, and also in the relationship between shell length (SL) and shell height (SH), shell height (SH) and shell width (SW) were represented by the linear equations: SL=1.1067SH+1.778, SW=0.6758SH-0.9824. Growth curves for shell height and total weight fitted to the von Bertalanffy equation were expressed as: SH$_t$ = 81.546(1-e$^{-0.176(t+0.381)}$), TW$_t$ = 227.65(1-e$^{-0.176(t+0.381)})^{2.8919}$.

• Journal of Energy Engineering
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• v.26 no.2
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• pp.39-49
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• 2017

Coffee is one of the most popular and consumed beverages in the world, which leads to a high contents of solid residue known as spent coffee grounds (SCG). As is known, coffee beans contain several classes of health related chemicals, including phenolic compounds, melanoidins, diterpenes, xanthines and carotenoids. The waste water coming out of coffee industries has high concentration of organic pollutants and is very harmful for surrounding water bodies, human health and aquatic life if discharged directly into the surface waters. Hence it is essential to treat and manage the coffee waste. Oyster shells are a waste product from mariculture that creates a major disposal problem in coastal regions of southeast Korea. In the study, the oyster shell waste was used to treat the coffee waste and its effluents. Oyster shells are calcined at $1000^{\circ}C$ for 2 h, and allowed to test the calcined CaO powder ability to inhibit the growth of bacteria in different aging coffee wastes. Calcined oyster shell powder showed anti-bacterial effect that inhibited cell growth of Escherichia coli and other bacterial forms. The antimicrobial activity of calcium oxide from oyster shell waste for biological treatment and utilization as a fertilizers with economic ecofriendly in nature.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.13-18
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• 2001

The relationship between shell length and ring radius in each ring group was expressed as a regression line. Therefore, there is a correspondence in each ring formation. Based on the monthly variation of the marginal index (Ml') of the shell, it is assumed that the ring of this species was formed once a year during the period of August to October, and the main period of the annual ring formation was August through September. The relationship between shell length (SL) and total weight (TW) was expressed by the equation TW = 2.2476 $\times$ 10$^{-5}$ SL$^{3.536}$ ($r^2$= 0.90). Shell length (SL) and shell height (SH; mm) were highly correlated with the equation SH = 0.7545 SL - 0.0145 ($r^2$= 0.93). The shell length (SL)-shell width (SW) relation was expressed by the equation SW = 0.5336 SL- 2.4253 ($r^2$= 0.87). Growth curves for shell length and total weight fitted to the von Bertalanffy's equation were expressed as follows: SL$_{t}$ =60.02[1 - e$^{-0.6458(t-0.3895)}$ ], Twt = 43.63[1 - e$^{0.6458(t-0.3895)}$ ]$^{3.536}$ .

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.458-464
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• 1994

The partitioning of dry matter into seed and pod-shell is important because yield increase can be achieved by improving the distribution rate of assimilation products to seeds. The present study was undertaken to characterize whether the partitioning of dry matter into seed was shoot- or root-controlled through graftiong techniques. Self- and reciprocal-grafts were made among four soybean genotypes, which were 'Baekunkong', 'Suwon 168', and two local soybeans with black seed coat (hereafter referred to as the 'black soybean'), 'Kangleungjarae' and 'Keumleungjarae'. Self-grafted black soybeans showed lower ratio of seed to pod-shell dry wight than self-grafted Baekunkong and Suwon 168. Varying the shoot genotypes in grafts resulted in significant differences in growth characters as well as pod and seed dry weight per plant at physiological maturity. There were significant effects of shoot genotypes on the ratio of seed to pod-shell dry weight, indication that the partitioning of dry matter into seed and pod-shell should be shoot- rather than root-controlled. The grafts with large pod-shell dry weight tended to partition relatively smaller dry matter into seed than pod-shell.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.4
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• pp.521-531
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• 1996

Inorganic and inorganic/organic microcapsules were prepared by spray drying. $K_{4}SO$ and clay were used as the core and colloidal silica as the shell for the inoroganic microcapsules. Forthe inorganic/organic microcapsules were used the inorganic microcapsule which were mentioned above (core) and ethyl cellulose (shell). To characterize the prepared microcapsule for the practical use, the homogenity of surface and pore volume are the dominent factors. At the volume ratio of 0.3/0.7 of core/shell, the spherical and homogeneous surfaces of inorganic microcapsule could be synthesized. In the case of inorganic/organic microcapsules, the weitht ratio was 0.76/0.24. The pore volume of inorganic/organic microcapsules decreases more than that of inorganic microcapsule. The more the amount of shell (ethyl cellulose) in inorganic/organic microcapsules increases, the more the coating became homogeneous and the pore volume decreased.

• The Korean Journal of Zoology
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• v.8 no.1
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• pp.1-7
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• 1965

The short-necked clam is distributed widely in Korean tidal flats and it is a much an important bivalve quantitatively as to control the production of the tidal flat. The shell of this clam tends to show remarkable morphological variations depending on the habitat. Under a seemingly favorable condition for the growth , the color pattern of shell of the clam is clear and obvious and having less weight and elongated shape, the ratios of shell length to both height and width are small . On the contrary , when the environment appears to be an unfavorable one, the shell is found to be heavy and stunted with smudgy color pattern. If this correlation between could be a basis for the judgement in suitability of growth environment for the clam. In the Ikawazu Bay, Japan, it is revealed that the elongated shell is produced from the coast outside of the Bay (1) , the stunted from the esturay (2) and the intermediate from the floodgate area (3) and the middle of the Bay (4). Followings are the results obtained from the morphological investigation of the claim in this Bay. 1. Relationship between the shell length and the largest shell rib length is linear and between the shell length and the shell width is also linear but with a critical point at the shell length of 17-20 mm. The ratio between the width and the largest rib length at a given shell length increases with the order of 1, 3, 4, and 2. 2. A gradual decreases of the ratio of the shell length to the largest rib length is observed when the former is less than 17-18 mm, and this ratio increases with the shell of longer. Also there is a different range of this ratio in each different location ; the greatest range in 2, the smallest in 1 and 4 being in between. 3. A similar biometric finding is apparent with the ratio between the length and width of the shell and the order in value is 2, 4, 1 and 3. 4. The ratios between the length and the largest rib length of elongated and stunted shell are 0.84-0.86 and 0.89-0.92, respectively , and those between the length and width are 0.40-0.51 and 0.49-0.58, respectively. 5. Generally , the elongated short necked clam shells are products of the tidal flat of good circulation of sea water with high salinity and smaller fluctuations of salinity and temperature within a day. The stunted shells are produced for tidal flats of opposite of above conditions.