Spherical fine cobalt powders were fabricated by new liquid reduction method. Commercial cobalt sufate heptahydrate was used as raw material. Also ethylene glycol was used as solvent and hydrazine-sodium hypophosphite mixture was used as reduction agent for the new liquid reduction method. A plate shaped cobalt powders with an approximately 300 nm were prepared by a traditional wet ruduction method using distilled water as solvent and hydrazine. Spherical fine cobalt powders with an average size of 1-3 μm were synthesized by a new liquid reduction method in 0.3M cobalt sulfate and 1.5M hydrazine-0.6M sodium hypophosphite mixture at 333K.

While Korea had achieved radical growth of construction industry, it also had accumulated problems in material, human and economical loss due to its low quality of safety level. Therefore, not only enterprises but also the nation is putting in a great deal of efforts for construction safety. However, its effect is not satisfiable. This research aims for change of construction cite by introduction of professional Safety Patrol Management System(SPMS) and consideration of its necessity. To consideration of its necessity, we compared and anaylzed average numbers of indicated dangers and safety accident incidences in each construction cites and we researched changes in worker's safety sense. It will establish the suitable design standards and suggest the basic database for estimating disaster and accident ratio.

In the present study, the effect of cysteine and NT or bisphenol A (BP) on in vitro aturation (IVM) of porcine oocytes were examined. COCs was cultured in NCSU-23 medium supplement with 10% FCS which had previously been covered with mineral oil and equilibrated in a humidified atmosphere of 5% CO2 and 95% air at 38℃. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 0.5～10.0 mM cysteine were 34.0±3.2%, 36.0±3.5%, 48.0±3.8%, 22.0±3.2%, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.5～5.0 mM NT for 48 hrs were 24.0±4.2%, 18.0±4.9%, 8.0±2.2%, respectively. NT affects oocyte in vitro maturation rate in a dose-dependent. This result were significantly lower than the control group. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM NT+5.0 mM cysteine (38.0±4.3%) were significantly higher than that of NT treatment. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.05～5.0 mM BP for 48 hrs were 20.0±4.7%, 10.0±5.3%, 6.0±3.2%, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with BP was significantly lower cultured non supplement of BP (44.0±3.5%). BP affects porcine oocyte maturation rate in a dose-dependent manner. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM BP+5.0 mM cysteine (32.0±3.2%) were increased than that of BP treatment.

These study was carried out to investigate the effects of the supplementation with sodium nitroprusside (SN) and nitric oxide (NO) of canine oocytes on IVM rates. Oocytes were incubated in TCM-199 supplement with at 0.03～0.10 mM SN and 0.3～1.0 mM NO for 48 hrs. Oocytes were transferred to 50 ul drops of maturation medium covered mineral oil and cultured in a CO2 incubator (5% CO2, 95% air, 38℃). The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03, 0.05, 0.07, 0.10 mM SN were 25.9±3.5%, 36.4±3.2%, 33.3±3.5%, 28.8±3.2%, respectively. The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03～0.07 mM SN were significantly increased compare to the control (26.0±2.2%). The in vitro maturation rates of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.3, 0.5, 0.7, 1.0 mM NO were 28.0±4.2%, 36.5± 3.6%, 30.0±3.8%, 19.2±3.5%, respectively. The in vitro maturation rate of oocytes in TCM-199 medium supplemented with 0.3 and 0.5 mM NO were significantly increased compare to the control (26.0±2.2%). The in vitro maturation rates of oocytes cultured for 12～48 hrs in TCM-199 medium supplement with 0.05 mM SN were 26.0±3.2%, 28.0±3.4%, 38.0±3.2%, respectively. The in vitro maturation rate of oocytes cultured for 12～48 hrs in TCM-199 medium supplement with 0.5 mM NO were 22.0±3.0%, 30.0±3.8%, 36.0±4.2%, respectively. These result was significantly increased compare to the control.

These study was to investigate the in vitro fertilization and viability of fresh and vitrified oocytes. Also, the developmental capacity of IVF and intracytoplasmic sperm injection (ICSI) oocytes were investigated. Then vitrification was performed with the use of 20% ethylene glycol + 20% DMSO + 0.5 M sucrose + 10% FCS + TCM-199 medium. Vitrification immature oocytes are cultured in vitrification solution for 10 min afterwards transferred to expose at room temperature for 5 min. and transferred to the ice water for 5 min. The oocytes were sealed in a 1.0 mm straw and placed in a LN2 container. Frozen oocytes were rapidly thawed in a water bath at 30～35℃, and then placed in TCM-199 medium containing 0.5 M sucrose for 5 min each, respectively, at 38℃. After being washed for 2～3 times, using fresh medium the oocytes were cultured in TCM-199 medium supplemented with 5% FCS at 38℃ in 5% CO2 and air. The normal morphology of fresh and vitrified-thawed oocytes were 87.1±2.1% and 54.8±2.5%, respectively. The viability rates of fresh and vitrified-thawed oocytes were 70.0±2.2% and 41.9±2.6%, respectively. Viability rates of vitrified-thawed oocytes were lower than that of fresh follicular oocytes (p<0.05). The in vitro maturation rates of fresh and vitrified oocytes were 45.1±3.6% and 28.9±4.4%, respectively. The IVF rates of fresh follicular and vitrified-thawed oocytes were 34.0±2.2% and 20.2±2.6%, respectively. The in vitro maturation and fertilization rates of vitrified-thawed oocytes were lower than those of the fresh follicular oocytes (p<0.05). A total of 350 oocytes were fixed and stained after co-incubation with spermatozoa, of which 88 had identifiable nuclear material. After IVF for 20 hrs, 25.1±3.4% of the oocytes found to have been penetrated by spermatozoas. Oocytes were fixed and stained after ICSI, and 105 oocytes contained identifiable nuclear material. After IVF and ICSI for 20 hrs, 34.3±3.4% and 59.0±2.0% of the oocytes were found to have been penetrated by spermatozoas. The developmental rates upon ICSI were significantly higher than those of the IVF method (p<0.05).

The in vitro maturation rate of vitrified-thawed canine oocytes was 30.8±3.4%. The in vitro maturation rate of vitrified oocytes was lower than that of the control (52.0±2.5%, p<0.05). The in vitro maturation rate of vitrified-thawed oocytes were significantly (p<0.05) lower than those of fresh oocytes. The in vitro maturation and developmental rates of the vitrified-thawed oocytes were 17.5±2.5% and 8.8±3.4%, respectively. This results were lower than the control group (43.6±3.2% vs 20.0±3.0%). SOD1 gene expression of 1～2 mm of follilce size were higher than those of above 6 mm follicle size. SOD2 gene expression of 1～2 mm of follicle size were significantly higher than those of above 6 mm follicle size (p<0.01). The expression pattern of SOD1, 2 was constantly expressed in both groups but strongly expressed in follicles (1～2 mm) group when compared to the above 6 mm follicles. SOD gene expression between groups the fresh and vitrified oocytes groups were significant differences in rates. However, RGS gene expression between groups the fresh and vitrified oocytes groups were no significant differences in rates.

For polyacrylonitrile (PAN) based carbon fiber (CF) process, we developed a lab scale wet spinning line and a continuous tailor-made stabilization system with ten columns for controlling temperature profile. PAN precursor was spun with a different spinning rate. PAN spun fibers were stabilized with a total duration of 45 to 110 min at a given temperature profile. Furthermore, a stabilization temperature profile was varied with the last column temperature from 230 to 275℃. Stabilized fibers were carbonized in nitrogen atmosphere at 1200℃ in a furnace. Morphologies of spun and CFs were observed using optical and scanning electron microscopy, respectively. Tensile properties of resulting CFs were measured. The results revealed that process conditions such as spinning rate, stabilization time, and temperature profile affect microstructure and tensile properties of CFs significantly.

These study was carried out to investigate the effects of the recovery time, diameter of oocytes on in vitro fertilization or intracytoplasmic sperm injection (ICSI). The in vitro maturation rates to MII stage of oocytes recovered at the inactive, follicular and luteal stages matured for 72 h were 1.4±0.0%, 43.4±3.2% and 10.8±2.7%, respectively. The fertilization rates of in vitro cultured oocytes recovered from ovaries at the in active, follicular and luteal stages were 0.0±0.0%, 15.7±3.4% and 7.6±3.5%, respectively. The in vitro maturation rate of oocytes recovered from ovaries at the follicular stage of the reproductive cycle was significantly higher than those at the inactive and luteal stages (p<0.05). The penetration rate determined that the percentages of oocytes with diameters in the <100 μm, 100 to 100 μm and 110 to 120 μm ranges were 17.5±4.7%, 43.9±4.5%, 21.3±3.4%, respectively. The penetration rate of oocytes with diameters between 100 to 110 μm was significantly higher than that of oocytes whose diameters were 100< μm and 110～120 μm (p<0.05). The penetration rate of oocytes determined that the percentages of ovaries with diameters between 1 to 5 mm and 6 to 10 mm were 32.9±3.2% and 17.5±3.7%, respectively. Thus, the diameters of the ovaries were significantly higher at 1 to 5 mm (p<0.05). A total of 264 oocytes were fixed and stained after co-incubation with sperm, of which 72 had identifiable nuclear material. After in vitro fertilization for 20 hrs, 27.3% of oocytes were penetrated by spermatozoas. Oocytes were fixed and stained after ICSI, of which 38 oocytes contained identifiable nuclear material. After in vitro fertilization and ICSI for 20 hrs, to 27.3% and 67.9% of oocytes were penetrated by spermatozoas. The in vitro fertilization rates by ICSI was significantly higher than that in vitro fertilization method (p<0.05).

The authors have demonstrated white oraganic light-emitting diodes (WOLED) using 1,4-bis[2-(4'-diphenylaminobiphenyl-4-yl)vinyl]benzene as fluorescent blue emitter and iridium(III) bis(5-acetyl-2-phenylpyridinato-N,C2') acetylacetonate as phosphorescent red emitter. The optimized WOLED using red host material as bis(2-methyl-8-quinolinato) -4-phenylphenolate exhibited proper color stability in comparison with the control device using 4,4'-N,N'-dicarbazole-biphenyl as red host. The white device showed a maximum luminance of 21100 cd/m2 at 14 V, luminous efficiency of 9.7 cd/A at 20 mA/cm2, and Commission Internationale de I'Eclairage (CIEx,y)coordinates of (0.32, 0.34) at 1000 cd/m2. The devices also exhibited the color shift with δCIEx,y coordinates of ± (0.01,0.01) from 100 to 20000 cd/m2.

이 논문에서는 게이트 절연막 위에 vapor deposition polymerization(VDP)방법을 사용하여 성막한 유기 점착층을 진공 열증착하여 유기 박막 트랜지스터(OTFTs)소자를 제작할 수 있음을 증명하였다. 우리가 제작한 Staggered-inverted top-contact 구조를 사용한 유기 박막 트랜지스터는 전기적 output 특성이 포화 영역안에서는 포화곡선을, triode 영역에서는 비선형적인 subthreshold를 확실히 볼 수 있음을 발견했다. 0.2μm 두께를 가진 게이트 절연막위에 유기 점착층을 사용한 OTFTs의 장 효과 정공의 이동도와 문턱전압, 그리고 절멸비는 각각, 약 0.4cm2/Vs, -0.8V, 106 이 측정되었다. 게이트 절연막의 점착층으로써 폴리이미드의 성막을 위해, 스핀코팅 방법 대신 VDP 방법을 도입하였다. 폴리이미드 고분자막은 2,2bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA)와 4,4'-oxydianiline(ODA)을 고진공에서 동시에 열 증착 시킨 후, 그리고 150℃에서 1시간, 다시 200℃에서 1시간 열처리하여 고분자화된 막을 형성하였다. 그리고 점착층이 OTFTs의 전기적 특성에 주는 영향을 설명하기 위해 비교 연구하였다.

In present study, the temporal characteristics of nine selected volatile organic compounds (VOCs), including four alcohol, 2 aldehyde, and 3 ketone compounds, in high-stories urban apartments over a 2-y period were investigated. The indoor VOC concentrations had generally a decreasing trend over the 2-y follow-up period. For examples, the 2E1H indoor concentration decreased from 10.8 ㎍/m3 for the first two months to 5.1 ㎍/m3 for the last two months. In addition, the DCA and ACT indoor concentrations decreased from 5.0 and 14 ㎍/m3 for the first two months to 2.2 and 6.4 ㎍/m3, respectively, for the last two months. The indoor-to outdoor concentration ratios over the 2-y period were much greater than 1, indicating that indoor VOC concentrations were higher than the outdoor VOC concentrations. Similar to those of the individual VOCs, the indoorto- outdoor concentration ratios of all three VOC groups were higher than 1 over the 2-y follow-up period, suggesting higher indoor concentrations of the three VOC groups than outdoor concentrations. In consistence with the results of VOC indoor concentrations, the VOC emission rates decreased gradually as time passed, due to the decreased VOC emission strengths of indoor sources. Finally, there was an initial sharp decrease in the indoor VOC concentrations followed by a slower decrease, indicating a multi-exponential decay model for the target VOCs, which was demonstrated by comparison of the residuals and the adjusted coefficient of determination associated with the one and two-exponential fits of each data set.

Environmental problems caused by the occurrence of carbon dioxide are recognized as a critical issue throughout the world. As a result, a measure for the use of cement and improvement of its quality must be sought out. In order to reduce the occurrence of carbon dioxide during the manufacturing process of cement, this study creates an alkali-activated slag cement that utilizes ground granulated blast furnace slag, an industrial by-product, and substitutes metakaolin as an alternative for silica fume to improve the process of manufacturing high-strength concrete and its quality. The study discerns the mechanical characteristics by measuring the flexibility and compressive strength through the mortar matrix and discerns the durability by conducting an acid resistance test and chloride ion penetration resistance test. Also, the study discerns the hydration products through an XRD test. Based on the results of such tests, it is anticipated that it may be used as a secondary product for concrete or buildings that require superior long-term strength and durability compared to regular Portland cement. However, as no clear results were found in this study regarding the substitution of metakaolin, it displayed mixed results in comparison to previous studies. Nevertheless, it is expected that metakaolin will become a more superior admixture if its issues are improved through continuous research studies.

This study was experimented by reviewing the possibility of applying non-sintered loess as a building material. Andthis study was to evaluate and compare flexural and compressive strengths characteristics of cementless mortar with non-sintered loess according to percentage of non-sintered loess and the type of curing without adding any cement. SEM,chloride ion penetration resistance and chemical resistance were also evaluated and compared to study characteristics ofcementless mortar with non-sintered loess. In order to evaluate the characteristics of cementless mortar with non-sinteredLoess. Test pieces were fabricated at 3, 7 and 28 days depending on the percentage of non-sintered loess and the typeof curing. And also normal portland cement mortar were fabricated to compare with cementless mortar with non-sinteredloess. The result of this study, Properties of cementless mortar with non-sintered loess strength are generally lower thannormal portland cement mortar. However cementless mortar with non-sintered loess which is mixed 20% show equallyas normal portland cement mortar. Also, cementless mortar with non-sintered loess show excellent results than normalportland cement mortar in the durability characteristics. The purpose of this study was to expand the utilizable scope ofnon-sintered loess and to use the basic data as a applying building material in the future.

Spikelets per panicle (SPP) is one of the most important traits associated with rice yield. In this study, IL28, a near isogenic line (NIL) developed by introgressing chromosomal segments from ‘Moroberekan’ into ‘Ilpumbyeo’ showed significantly higher number of spikelets per panicle than the recurrent parent, ‘Ilpumbyeo’. Quantitative trait locus (QTL) analysis in 243 F2 plants derived from a cross between IL28 and Ilpumbyeo indicated that a QTL for spikelets per panicle, qSPP6 was located in the interval RM3430 - RM20580. The Moroberekan allele increased SPP. The fact that QTLs for panicle length and the number of secondary branches were mapped in the same interval as qSPP6 appears to indicate that this locus was associated with panicle structure. To map the QTL more precisely, substitution mapping of qSPP6 using F3 lines was conducted. Substitution mapping with 41 F3 lines further narrowed the interval containing not only qSPP6 for spikelets per panicle but also qNDW6 for node width to about 680-kb between markers RM20521 and RM20572 based on Nipponbare genome sequence. The locus, qSPP6 is of particular interest because of its independence from undesirable height and flowering time. SSR markers tightly linked to the qSPP6 will facilitate cloning of the gene underlying this QTL as well as marker assisted selection for variation in SPP in the breeding program.

Early diagnosis of crop growth at various growth stages will help to make an optimum fertilization. If we can diagnose crop growth at around the time of topdressing of N fertilizer, N fertilization can be made based on crop growth and target crop yield, which may provide economic and environmental benefits as compared with fixed rate fertilization. In this study we devised methods to diagnose rice growth non-destructively at panicle initiation stage and to determine N topdressing rate. SPAD-502, Field Scout CM1000 and Green Seeker GNDVI were used to diagnose the growth status of rice grown at different soil N fertilities. The values measured by the diagnostic equipments at rice panicle initiation stage were then regressed to rice grain yield. It was found that CM1000 and GNDVI were more efficient than SPAD to diagnose rice growth. Therefore, a multivariate model with CM1000 and GNDVI values was developed to make a decision of N fertilization at rice panicle initiation stage. In a subsequent field study, N fertilization determined by non-destructive growth diagnose by CM1000 and GNDVI, and the multivariate model could minimize N fertilizer use to achieve our target yield, resulted in significant reduction of N fertilizer as compared with fixed rate N fertilization.