• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.161-165
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• 2000

Spectroradiometric light transmittance from 300 to 1,100nm in the greenhouse covered with the CEM BIO polyethylene film was greater than that in the greenhouse covered with polyethylene film (control). As a whole, solar radiation transmittance into greenhouse was a half level, due to shades caused by double layer covering, frame and equipment. Net radiation energy emitted throughout surface of the greenhouse covered with CEM BIO polyethylene film was 5,424.5W.m$^{-2}$ , which was lower by 2.9% as compared to that of the greenhouse covered with polyethylene film. Photosynthetically active radiation from 400 to 700nm of the greenhouse covered with CEM BIO polyethylene film was 3,861.2W.m$^{-2}$ , which was higher by 3.8% as compared to hat of the greenhouse covered with polyethylene film. Accumulated minimum air temperature from Oct. 7, 1997 to Oct. 16, 1997 of the greenhouse covered with CEM BIO polyethylene film was 100.5$^{\circ}C$, which was higher by 2.5$^{\circ}C$ as compared to that of the greenhouse covered with polyethylene film. As results, height, stem diameter, leaf count, leaf area, fresh weight and dry weight of green pepper plants and canopy production structure measured at 30 days after transplanting were enhanced. Mean fruit weight n the greenhouse covered with CEM BIO polyethylene film was 11.28 g and 1.25 g greater as compared to that in the greenhouse covered with polyethylene film, due to increased fruit diameter and flesh thickness. Percent marketable fruits produced in the greenhouse covered with CEM BIO polyethylene film were 96.1%, and was greater by 2.7% thant that of the greenhouse covered with polyethylnee film due to decreased infection, sterility, severe curve and twisted fruits. The green pepper yield of the greenhouse covered with CEM BIO polyethylene film from Nov. 19, 1997 to Feb. 3, 1998 was greater by 974 kg per hectare than that of the greenhouse covered with polyethylene film, but the total fruit had no difference.

• Applied Microscopy
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• v.38 no.4
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• pp.279-284
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• 2008

The phase change materials have been extensively used as an optical rewritable data storage media utilizing their phase change properties. Recently, the phase change materials have been spotlighted for the application of non-volatile memory device, such as the phase change random access memory. In this work, we have investigated the crystallization behavior and microstructure analysis of In-Sb-Te (IST) thin films deposited by RF magnetron sputtering. Transmission electron microscopy measurement was carried out after the annealing at $300^{\circ}C$, $350^{\circ}C$, $400^{\circ}C$ and $450^{\circ}C$ for 5 min. It was observed that InSb phases change into $In_3SbTe_2$ phases and InTe phases as the temperature increases. It was found that the thickness of thin films was decreased and the grain size was increased by the bright field transmission electron microscopy (BF TEM) images and the selected area electron diffraction (SAED) patterns. In a high resolution transmission electron microscopy (HRTEM) study, it shows that $350^{\circ}C$-annealed InSb phases have {111} facet because the surface energy of a {111} close-packed plane is the lowest in FCC crystals. When the film was heated up to $400^{\circ}C$, $In_3SbTe_2$ grains have coherent micro-twins with {111} mirror plane, and they are healed annealing at $450^{\circ}C$. From the HRTEM, InTe phase separation was occurred in this stage. It can be found that $In_3SbTe_2$ forms in the crystallization process as composition of the film near stoichiometric composition, while InTe phase separation may take place as the composition deviates from $In_3SbTe_2$.

• Korean Journal of Materials Research
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• v.8 no.12
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• pp.1158-1164
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• 1998

Aluminium sulfate solution was prepared by sulfuric acid treatment from gibbsite. Aluminium sulfate hydrate [$Al_2(SO_4)_3$ · $nH_2O$] was precipitated from aluminium sulfate solution by adding it into ethylalcohol. From XRD analysis as-prepared $Al_2(SO_4)_3$ · $nH_2O$ was confirmed to have mixed-crystalization water(n=18, 16, 12, 6). The average water of crystalization calculated from thermogravimetry(TG) was 14.7. Aluminium sulfate hydrate [$Al_2(SO_4)_3$ · $nH_2O$] was thermally decomposed and converted to $Al_2(SO_4)_3$ at $800^{\circ}C$, $\gamma-Al_2O_3$ at $900-1000^{\circ}C$, and $\alpha-Al_2O_3$ at $1200^{\circ}C$. Ni-doped $\gamma-Al_2O_3$, was synthesized from the slurry of as-prepared $\gamma-Al_2O_3$, with the ratio of [Ni]/[Al]=0.5. The reaction conditions of synthesis were determined as initial pH 9.0 and temperature $80^{\circ}C$ The basicity(pH) of slurry was controlled by using urea and $NH_4OH$ solution. Urea was also used for deposition-precipitation. For determining termination of reaction, the data acquisition was performed by oxidation reduction potential(ORP), conductivity and pH value in the process of reaction. Termination of the reaction was decided by observing the reaction steps and rapid decrease in conductivity. On the other hand, BET(Brunauer, Emmett and Teller) and thermal diffusity of Ni- doped $\gamma-Al_2O_3$, with various content of Ni were measured and compared. Thermal stability of Ni- doped $\gamma-Al_2O_3$ at $1250^{\circ}C$ was confirmed from BET and XRD analysis. The surface state of Ni-doped $\gamma-Al_2O_3$ was investigated by X-ray photoelectron spectroscopy(XPS). The binding energy at $Ni2P_{3/2}$ increased with increasing the formation of $NiAl_2O_4$ phase.

• Journal of Conservation Science
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• v.30 no.3
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• pp.263-275
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• 2014

It's shown how to proceed the study on Manufacturing techniques & Conservation to the Iron Pot from Cheonmachong Ancient Tomb(the 155th Tomb in Hwangnam-dong). In order to investigate manufacturing techniques of the Iron Pot, some parts of the relic were gathered. After mounting, polishing and etching on the relic, analyzing the metal microstructure was conducted. Also it's conducted a SEM-EDS analysis on the nonmetallic inclusion. White iron structure was observed in the metallurgical structure inspection, SEM-EDS analysis. It seems to be dried slowly at room temperature after casting, doesn't look as particular heat treatment to improve brittleness. It is estimated that it's as the handle seam side were verified about 3cm inch wide, 1.5 thick in center of body, so 2 separate half-completed products was cast with width-type mould. The manufacturing techniques Using white cast iron structure, width-type mould are observable to the Iron Pot excavated from Sikrichong Ancient Tomb & Hwangnamdaechong grand Ancient Tomb around those were constructed the same time. It's able to recognize that it's almost identical manufacturing techniques at that time. Conservation is generically following those are survey of pretreatment, foreign material removal, stabilization, restoration and color matching in the order. cleaning & drying were added to the process as occasion demands. The strengthening treatment were difficult with artifact's volume, low concentration Paraloid NAD-10 solution was spread two or three times with a brush, surface hardening also came up with 15wt% Paraloid NAD-10 solution after the conservation was complete. There were connection & restoration for the restoration to the damage after modeling forms that it's similar to damaged parts by using the Fiber Reinforced Plastic resins(POLYCOAT FH-245, mold laminated type). Throughout this research, capitalizing on accumulations of measurements about the production technique of Iron Pot in the time of the fifth and 6th centuries is no less important than the Iron artifact's conservation for a better study in the future.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.137-145
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• 2000

The embryonic and larval development of Chelon lauvergnii (Eydoux & Souleyet) was surveyed by incubating artificially inseminated eggs with parent fishes obtained at Kang-wha island in the mid-western coastal area of Korea on June, 1997. The fertilized eggs were transparent, spherical in shape, measuring 0.95~1.08 mm in diameter, having a large oil globule, and their perivitelline space narrow, and began to hatch at 40 hrs. in water temperature $22{\pm}1^{\circ}C$. The newly hatched larvae were 2.35~2.68 mm in total length with 23 myomeres, anus opened, mouth closed, preanal length 58.7~61.6% of total length, oil globule located in posterior end of yolk sac. Melanophores, branch in shape, were distributed mainly along the ventro-lateral region of trunk part and a few on the anterior end of caudal part and surface of oil globule. The larvae measuring 3.08~3.36 mm in total length absorbed yolk material completely in 3 days after hatching, in which air bladder began to appear and mouth opened. In 8 days after hatching, the larva was measured 5.09 mm in total length, its posterior end of notochord began to flex upward and the caudal fin rays differentiated as 7, finfold of the second dorsal and anal fins appeared. In this time, melanophores, branch in shape, were concentrated in the anterior half region of the caudal part and a few also distributed on the top of head, snout region, ventral margin of lower jaw and isthmus region. In 12 days after hatching, the larva measuring 8.48 mm in total length completed all the fins (D. IV-9; P1. 16; P2. I, 5; A. II, 9) and reached to the juvenile stage. Melanophores, in this time, were distributed on the mid-lateral region of the caudal part in enlargment than before and a few also found in the dorso-lateral region of the trunk part, and in the cheek region.

• The Korean Journal of Malacology
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• v.20 no.2
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• pp.125-130
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• 2004

Arkshell, Scapharca broughtonii spats were placed in natural environmental condition for 30 days from July 28 to August 27, 2004, in order to estabilish intermediate culture technique. Growth and survival of the spats in different intermediate culture areas with various culture methods were measured. Water temperature of studied area ranged from 24.1 to 28.5$^{\circ}C$, salinity was 15.4 to 33.3 psu, dissolved oxygen was 3.92 to 12.6 mg/l. Scapharca broughtonii spats cultured in Yeosu developed the best, 10.15 ${\pm}$ 1.12 mm in average shell length, and the highest survival was recorded as 77% in Namhae. Shell lengths of the Scapharca broughtonii spats cultured in the water depths of 2, 5, and 10 m were 7.14 ${\pm}$ 1.14 mm, 6.98 ${\pm}$ 1.74 mm and 6.27 ${\pm}$ 1.33 mm, and the survivals showed 75.5%, 77.0% and 76.5%, respectively. When 1 mm, 2 mm, and 3 mm-sized spats were cultured for 30 days in water depth of 5 m, the shell length increased to 6.73 ${\pm}$ 1.46 mm, 6.98 ${\pm}$ 1.74 mm and 7.04 ${\pm}$ 1.19 mm, and survivals were 67.0%, 77.0% and 58.5%, respectively. The shell lengths of spat cultured for 30 days in mesh sizes of 1 ${\times}$ 1 mm, 2 ${\times}$ 2 mm and 3 ${\times}$ 3 mm, 5 m below the surface were 8.14 ${\pm}$1.23 mm, 8.26 ${\pm}$ 1.19 mm and 8.78 ${\pm}$ 1.16 mm, and survivals were 41.5%, 43.0% and 44.5%, respectively.

• Clean Technology
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• v.24 no.1
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• pp.55-62
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• 2018

The adsorbent used in water-adsorption cooling system utilizing low-temperature heat of below $90^{\circ}C$ is required to exhibit high water uptake capacity at a relative humidity ($P/P_0$) between 0.1 and 0.3. Mesoporous silica (MCM-41) and MOF(MIL-101) exhibit quite large water adsorption capacity under saturated water vapor at $35^{\circ}C$. However, these adsorbents show small water adsorption capacity ($0.027{g_{water}\;g_{ads}}^{-1}$, $0.074{g_{water}\;g_{ads}}^{-1}$, respectively) in the relative humidity ($P/P_0$) range of 0.1 to 0.3. In this study, the surface properties of mesoporous silica and MOF were modified by simple methods to develop an adsorbent having a higher water uptake than the conventional water adsorbents at a relative humidity ($P/P_0$) of 0.1 ~ 0.3. In the case of mesoporous silica (MCM-41) exhibiting mainly water adsorption at $P/P_0=0.5{\sim}0.7$, aluminum species was functionalized on the mesopore walls and then cations existing near the aluminum were exchanged with various cations (e.g., $Na^+$, ${NH_4}^+$, and $(C_2H_5)_4N^+$). In addition, 20 wt% (to total weight of the composites) of hygroscopic inorganic salt ($CaCl_2$) was impregnated on the MCM-41. In the case of the MIL-101 (MOF), 20 wt% of hygroscopic inorganic salt ($CaCl_2$) was impregnated on the MIL-101. The MCM-41 which was ion-exchanged with various cations has main adsorption branch around 0.5 of $P/P_0$ which was slightly shifted with low-pressure direction in comparison with pristine MCM-41. However, tiny increases were observed on the adsorption in the range of $P/P_0$ between 0.1 and 0.3. After salt impregnation on the MCM-41, the adsorption capacity under $P/P_0=0.1{\sim}0.3$ at $35^{\circ}C$ was increased from $0.027{g_{water}\;g_{ads}}^{-1}$ to $0.152{g_{water}\;g_{ads}}^{-1}$. In the case of MIL-101, the amount of water adsorption at $35^{\circ}C$ under $P/P_0=0.1{\sim}0.3$ was increased from $0.074{g_{water}\;g_{ads}}^{-1}$ to $0.330{g_{water}\;g_{ads}}^{-1}$ after the salt impregnation.

• Journal of Sericultural and Entomological Science
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• v.24 no.2
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• pp.55-72
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• 1983

These studies were done to find out any difference, ultrastructural, physical or chemical, between the shells of diapausing and non-diapausing eggs of the silkworm, Bombyx mori L. 1. From the electron-microscopic observation, the egg shells have four distinctive layers. In addition to the four layers, the shells in the diapausing eggs has another layer with low electron density on its surface. 2. The permeability of the egg shell to hydrochloride was much lower in diapausing egg than in non-diapausing egg. Also the permeability changed in the opposite directions with the egg age: the diapausing eggs decreased while non-diapausing ones increased. 3. The permeability increased when the diapausing egg shell was treated with HCl. When they were treated with ether, however, the increase in permeability was much smaller. It seems there was an ether soluble material involved in the content of the egg shell. 4. The diapausing eggs were also much more resistant to desiccation than the non-diapausing ones. The former, when treated with HCl or chilling, became less resistant to desiccation. 5. The positive histochemical response of the egg shell to PAS-Alcian blue and protein stainings suggests presence of abundant proteins and carbohydrates in the egg shell. On the other hand, the staining response to lipid was more positive in the inner layers than in the outer layer of the shell. 6. The egg shell adhesives seems to be mucopolysaccharides produced by colleterial glands, since the oviposited eggs showed a positive responses to carbohydrate and negative to lipid-staining chemicals, but not the mature oocytes in the ovarioles. 7. There were two bands on the electrophoretic pattern of the SH proteins extracted from the egg shells both in the diapausing egg and non-diapausing one: a slow moving major component and a fast moving minor one. However, the electrophoretic mobility showed a difference in the minor components between them. It is evident that the fast moving minor one of non-diapausing egg ran a little further than that of diapausing egg. 8. In amino acids analysis, no significant differences were found in their composition between diapausing and non-diapausing egg and SH proteins contain relatively more glycine and less cystine.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.115-124
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• 2020

Sustainable plastics can be mainly categorized into (1) biodegradable plastics decomposed into water and carbon dioxide after use, and (2) biomass-derived plastics possessing the carbon neutrality by utilizing raw materials converted from atmospheric carbon dioxide to biomass. Recently, biomass-derived engineering plastics (EP) and natural nanofiber-reinforced nanocomposites are emerging as a new direction of the industry. In addition to the eco-friendliness of natural resources, these materials are competitive over petroleum-based plastics in the high value-added plastics market. Polyesters and polycarbonates synthesized from isosorbide and 2,5-furandicarboxylic acid, which are representative biomass-derived monomers, are at the forefront of industrialization due to their higher transparency, mechanical properties, thermal stability, and gas barrier properties. Moreover, isosorbide has potential to be applied to super EP material with continuous service temperature over 150 ℃. In situ polymerization utilizing surface hydrophilicity and multi-functionality of natural nanofibers such as nanocellulose and nanochitin achieves remarkable improvements of mechanical properties with the minimal dose of nanofillers. Biomass-derived tough-plastics covered in this review are expected to replace petroleum-based plastics by satisfying the carbon neutrality required by the environment, the high functionality by the consumer, and the accessibility by the industry.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml