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In this study, a ferroelectric layer was formed on a ferroelectric device via plasma enhanced atomic layer deposition. The device used 50 nm thick TiN as upper and lower electrodes, and an Hf0.5Zr0.5O2 (HZO) ferroelectric material was applied to fabricate a metal–ferroelectric–metal-type capacitor. HZO ferroelectric devices were fabricated in accordance with three principles to improve their ferroelectric properties. First, the HZO nanolaminate thickness of the ferroelectric layers was varied. Second, heat treatment was performed at 450, 550, and 650 °C to investigate the changes in the ferroelectric characteristics as a function of the heat-treatment temperature. Finally, ferroelectric thin films were formed with or without seed layers. Electrical characteristics such as the I–E characteristics, P–E hysteresis, and fatigue endurance were analyzed using a semiconductor parameter analyzer. The crystallinity, component ratio, and thickness of the nanolaminates of the ferroelectric thin film were analyzed via X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. The residual polarization of the (20,20)*3 device heat treated at 550 °C was 23.94 μC/cm2, whereas that of the D(20,20)*3 device was 28.18 μC/cm2, which improved the characteristics. In addition, in the fatigue endurance test, the wake-up effect was observed in specimens with bottom and dual seed layers, which exhibited excellent durability after 108 cycles.

White light-emitting diodes (WLEDs) find numerous applications owing to their high power efficiency and long service life. The Y3Al5O12:Ce3+ phosphor ceramic (YAG PC) is a promising packaging material for such LEDs but exhibits several limitations such as the need for a high sintering temperature. Herein, a high-density PC for application in WLEDs was prepared by mixing nanoYAG powder (wavelength =550 nm) and tetraethyl orthosilicate (TEOS, sintering agent) followed by uniaxial pressing, cold isostatic pressing, and sintering in N2:H2 (95:5, v/v). The sinterability of samples prepared using different TEOS contents and sintering temperatures was evaluated by density measurement and scanning electron microscopy, while photometric characteristics such as wavelength and luminous efficacy were evaluated by photoluminescence spectrometry. Sinterability and relative density increased with increasing TEOS content and sintering temperature, with the best results (luminous efficacy =100.19 lm/W, density =4.727 g/cm3, relative density = 98.5 %, center wavelength =550 nm, color coordinates = (0.3099, 0.3304)) obtained at a TEOS loading of 1 wt.% and a sintering temperature of 1500 °C. Thus, this study confirmed the suitability of YAG PC for application in white-light automotive headlamps based on blue LEDs.

대형 해조류(macroalgae)와 식물성플랑크톤을 포함하는 해 양 조류(marine algae)는 지구 산소의 50-70%를 생산하고 CO2 의 약 25%를 흡수하고 침적하여 탄소순환에 관여하는 것으로 알려져 있다. 홍조류인 무절산호조류는 북극에서 남극까지, 환 경이 열악한 조간대 상부에서부터 차갑고 매우 약한 광이 도 달하는 한계 수심(최대 268 m)까지, 광범위한 분포를 보이며 (Littler and Littler, 1985; Bjork et al., 1995), “Maerl beds” (or rhodoliths)를 형성하는 Phymatolithon calcareum과 같이 부 착하지 않는 그룹과 생물과 무생물의 표면을 피복하여 서식하 는 각상형(crustose form) 그룹으로 구분된다. 무절산호조류인 Maerl은 해양 저서군집의 피복된 면적에서 “Big Four” (켈프 대, 해조숲, 해초대, 무절산호초대)에 포함되며(Foster, 2001), 유럽에서는 정원의 비료로 경제적 가치가 높아 프랑스의 Brittany해안에서는 1987년에 450,000톤이 채취되는 등(Potin et al., 1990), 과다 수확으로 개체군이 감소되고 있는 실정이다. 전 세계적으로 조하대에 주로 서식하는 각상형 무절산호조류는 산호초의 석회화율에 기여하고 다양한 저서생물 유생들의 착 생을 유도하는 생태적 기능을 하고 있다(Fabricius and De’ath, 2001). 일본에서는 1950년대 초에 갯녹음 해역이 급격하게 증 가되는 것을 관찰하고 다시마 숲(Laminaria beds)의 복원을 시

The effects of temperature on spore release, growth and photosynthetic efficiency of Lithophyllum yessoense and Hildenbrandia rubra were examined. L. yessoense was collected at Galnam and H. rubra was collected at Gyeokpo, Korea. The experimental temperatures were different for spore release (10, 15, ), sporeling growth (10, 15, 20, 25, ) and photosynthetic efficiency (10, 15, 20, ). All other culture conditions were the same: 34 psu, 12:12 LD and photon . Spore liberation was maximal at for L. yessoense and at for H. rubra. After 14 days, the surface area of L. yessoense was 0.031 at and for H. rubra was 0.032 at . Sporelings of L. yessoense were a dark-red color and grew in a round shape. In contrast, H. rubra was bright pink and changed from a round shape in the early growth stage to later become flabelliform. Photosynthetic efficiency was highest between in both species. In conclusion, L. yessoense and H. rubra display different physiological features based on the optimal temperatures for spore release and sporling growth.

An ultrafiltration (UF) unit was used for tertiary wastewater treatment at a wastewater plant. The pilot study showed that UF is effective to remove turbidity, total bacteria and coliform bacteria from the secondary effluent to obtain high quality filtrate for water reuse, but UF is not very effective in the removal of dissolved substances such as colour, UV254 and TOC, and the removal efficiency and permeate flux can be improved by conducting PAC adsorption or coagulation prior to UF operation. The backwash is essential to obtain a higher permeate flux.

The benthic algal community structures of the seaweed biomass, vertical distribution of dominant seaweeds, and species composition were examined on the rocky shores of Ongdo, Jusamdo, and Woejodo Islands, Korea, in August 2006. A total of 68 seaweeds were identified, comprising 5 green, 11 brown, and 52 red algae from the three study sites. The number of species at Ongdo (32 species) was less than that at Jusamdo (45 species) and Woejodo (44 species). Jusamdo exhibited the maximum seaweed biomass (73.99 g dry wt/m 2 ), while the minimum value was found at Woejodo (36.90 g dry wt/m 2 ). On the three islands, coarsely branched forms were the most dominant functional group in terms of species number and biomass among benthic algal species. The dominant species were Gelidium amansii, Chondrus ocellatus, and Chrysymenia wrightii at Ongdo, Sargasum thunbergii, Ulva pertusa, and Sargassum fusiformis at Jusamdo, and U. pertusa, Undaria pinnatifida , and Corallina pilulifera at Woejodo. Perennial seaweeds were abundant at Ongdo (G. amansii and C. ocellatus) and Jusamdo (S. thunbergii and S. fusiformis), whereas the sheet form of U. pertusa was relatively abundant at Woejodo Island.

The intertidal benthic macroalgal floras of 19 uninhabited islands were investigated in the Goheung area, South Sea, Korea, in June 2008. Seaweed community structures on the rocky shores of four (Naemaemuldo, Ceoldo, Araedombaeseom, and Jinjioedo) of the 19 islands were also examined. Eighty macroalgal species were identified, including 13 green, 19 brown, and 48 red algae. The maximum number of species was found at Naemaemuldo, with 35 species, and the minimum was at Aredombaeseom, with 21 species. Seaweed biomass ranged from 21.39-76.22 g dry 2wt/m , with a maximum at Naemaemuldo, and minimum at Jinjioedo. Sargassum thunbergii was a representative species, distributed widely in the intertidal zone of the four islands. Subdominant seaweeds were Corallina pilulifera and Ulva pertusa at Naemaemuldo and Jinjioedo, respectively. Also, Ishige okamurae was dominant at Ceoldo and Araedombaeseom. Six functional seaweed forms were found at each study site, except for Araedombaeseom, which had four functional groups. On the rocky shores of the four sites, a coarsely-branched form was the most dominant functional group ranging from 44.44-61.90% in species number and 72.42-91. 09% in biomass. In conclusion, among the four study sites, the shore of Naemaemuldo Island had the best ecological status, with the highest number of species, and greatest biomass (mainly brown and red algae) and functional form diversity of seaweeds. Furthermore, on the rocky shore of Naemaemuldo, coarsely branched- and joint calcareous-form seaweeds, which grow in clean and undisturbed environmental conditions, were the representative functional forms.Key words: Algal flora, Biomass, Community, Dominant species, Functional form

【The effects of temperature, light, and salinity on the growth of Costaria costata and Undaria pinnatifida juveniles were examined in laboratory cultures. In a cultivation farm, the monthly yield and density were also investigated between December and April for C. costata and between December and March in 2007 and 2008 for U. pinnatifida. The relative growth rates (RGRs) were greater at $20{\sim}60\;{\mu}mol$ photons $m^{-2}s^{-1}$ than at low ( $0{\sim}10\;{\mu}mol$ photons $m^{-2}s^{-1}$ ) and high ( $100{\sim}180\;{\mu}mol$ photons $m^{-2}s^{-1}$ ) irradiance levels. The optimal growth conditions for the two species were $17^{\circ}C$ , 35 psu, $60\;{\mu}mol$ photons $m^{-2}s^{-1}$ , and a daylength of 12 h, indicating that C. costata and U. pinnatifida have very similar growth responses to temperature, light, and salinity. However, the growth responses of the two species to various environmental factors were different; C. costata grew faster than U. pinnatifida but the latter species grew well at low salinity. The monthly yield of C. costata and U. pinnatifida increased steadily over the study period, and it was maximal in March for both species, but the yield of U. pinnatifida was greater than that of C. costata.】

Biosorption has been developed as an effective and economic method to treat wastewater containing low concentrations of metal pollutants. In this study, a bacterium, Citrobacter freudii, was used as a biosorbent to adsorb uraniumions. The factors which influence the adsorption of uranium by Citrobacter freudii were investigated, including pH, the strain dosage and the initial concentrate of uranium. The results showed that the adsorption efficiency increased with the increased of pH in the beginning of the adsorption and reached its maximum at pH 6; when the strain dosage and the initial concentrate of uranium were 6.0g/L and 20mg/L, respectively, the adsorption efficiency reached 93.89% and 94.68%, respectively. The authors investigated the active sites of bacteria for biosorption and the results proved that carboxyl in the cell wall played an important role in biosorption.

Two diallelic markers at candidate gene loci, the prolactin receptor 3 (PRLR3) gene and the retinol-binding protein 4 (RBP4) gene were evaluated for their association with growth and litter size traits in Berkshire. Genetic evaluation was conducted for 5,919 pigs with pedigree information, which included 3,480 growth performance records and 775 litter size records of 224 sows. From the same herd, genotyping was carried out on 144 and 156 animals for PRLR3 and RBP4, respectively. After assigning a genotype to subjects in which both parents had a homozygous genotype, numbers of genotyped animals increased to 474 and 338, for the PRLR3 gene and RBP4 gene, respectively. The genotype effects of two markers were estimated with breeding values of the genotyped animals. The additive effects of total number of piglets born and number of piglets born alive in the PRLR3 locus were -0.28 and -0.13, respectively. The dominance effect of the RBP4 locus on average daily gain was -10.58 g. However, the polymorphism of the RBP4 locus in total number of piglets born and number of piglets born alive has shown -0.34 and -0.33 of the additive genetic effects. In view of the results, MAS (marker-assisted selection) favoring B alleles of RBP4 and PRLR3 loci could potentially accelerate the rate of the genetic improvement in the litter size traits.