In this study, we synthesize silica-core gold-satellite nanoparticles (SGNPs) for the surface-enhanced Raman scattering (SERS) based sensing applications. They consist of gold satellite nanoparticles (AuNPs) fixed on the silica core nanoparticles, which sizes of AuNPs can be tunned by varying the amount of reactants (growth solution and reducing agent). Their surface plasmon resonance (SPR) properties were characterized by using UV-vis spectroscopy, showing that the growth of AuNPs on silica cores leads to the light absorption in the longer wavelength region. Furthermore, the size increase of AuNPs exhibited the dramatic change in SERS activity due to the formation of hot spots. The optimized SGNPs showing enhancement factor ~3.8x106 exhibited a detection limit of rhodamine 6G (R6G) as low as 10-8M. These findings suggest the importance of size control of SGNPs and their SPR properties to develop highly efficient SERS sensors.

화학살충제, 화학비료를 사용하지 않는 구기자 친환경 재배지에서 많은 종류의 해 충 발생이 증가하여 친환경 농법에 어려움을 주고 있다. 본 연구는 충청남도 청양군 일원의 친환경 구기자 재배지 4농가를 선정하여 2012년 5월부터 2014년 9월 중순까 지 3년간 해충의 발생상을 조사하였으며, 친환경재배를 위한 구기자의 작기에 따라 발생하는 주요 해충의 생태학적 조사를 하여 방제적기의 기초자료를 제공하고자 실 시하였다. 그 결과 구기자나무의 초엽기인 5월 하순과 6월 초순에는 복숭아혹진딧물 (Myzus persicae)에 의한 피해가 심하며, 6월 중순부터는 열점박이잎벌레(Lema decempunctata)에 의한 피해가 심하고, 큰이십팔점박이무당벌레(Henosepilachna vigintioctomaculata), 뿔나방류(Hedma spp.)의 피해는 연중 계속되었다. 열매가 열 리는 7월 하순부터는 갈색날개노린재(Plautia stali)와 썩덩나무노린재(Halyomorpba balys)등 노린재류의 피해가 점차 증가하게 된다. 구기자혹응애(Eriophys macrodonis) 의 경우 2014년도 7월 초순부터 9월 중순까지 밀도가 급증하였는데 ‘12년도와 ’13 년도에 비하여 그 수가 약 5배 이상 증가하였다. 이는 6월 중순부터 구기자혹응애 의 방제가 미흡하여 대량 발생하였을 것으로 추정되며 대량발생하게 된 요인은 좀 더 검토를 할 필요성이 있다.

큰이십팔점박이무당벌레는(Henosepilachna vigintioctomaculata) 가지과 식물 인 감자, 토마토, 가지, 구기자등을 가해하는 주요 해충이며, 2012부터 충남 청양군 일원 친환경재배지에서 6월 초순부터 8월 중순에 걸쳐 연속적으로 피해를 주고 있 다. 실내에서 구기자 잎을 먹이로 하여 큰이십팔점박이무당벌레 알, 유충의 온도별 (15, 20, 25, 30℃) 발육기간을 조사하였다. 그 결과, 각각의 온도별 부화율은 55.6%, 76.3%, 91.5%, 56.1%로 25℃에서 가장 높았다. 부화기간은 각각의 온도에 서 10.8일, 7.7일, 5.2일, 3.7일로 온도가 높아질수록 기간이 짧아졌다. 1령에서 성 충이 되는 기간은 25℃에서 가장 시간이 짧았고 령기별 발육기간, 용화, 우화하기 까지의 기간도 25℃에서 가장 짧게 나타났다. 또한 온도가 낮을수록 탈피와 우화기 간이 길어지는 양상을 보이는데, 이와 달리 30℃에서는 오히려 25℃보다 길게 나타 났다.

Methanol was directly produced by the partial oxidation of methane with four-component mixed oxide catalysts. Four-component(Mo-Bi-Cr-Si) mixed oxide catalysts were prepared by the co-precipitation and sol-gel methods. The catalyst prepared by the sol-gel method showed about eleven times higher surface area than that prepared by the co-precipitation method. From the O2-TPD experiment of the prepared catalysts, it was proven that there exists two types of oxygen species, and the oxygen species that participates in the partial oxidation reaction is the lattice oxygen desorbing around 750℃. The optimum reaction condition for methanol production was 420°C, 50 bar, flow rate of 115 mL/min, and CH4/O2 ratio of 10/1.5, providing methane conversion and methanol selectivity of 3.2 and 26.7%, respectively.

In this study, we prepare polymer solar cells incorporating organic ligand-modified Ag nanoparticles (O-AgNPs) highly dispersed in the P3HT:PCBM layer. Ag nanoparticles decorated with water-dispersible ligands (W-AgNPs) were also utilized as a control sample. The existence of the ligands on the Ag surface was confirmed by FT-IR spectra. Metal nanoparticles with different surface chemistries exhibited different dispersion tendencies. O-AgNPswere highly dispersed even at high concentrations, whereas W-AgNPs exhibited significant aggregation in the polymerlayer. Both dispersion and blending concentration of the Ag nanoparticles in P3HT:PCBM matrix had critical effects onthe device performance as well as light absorption. The significant changes in short-circuit current density (JSC) of thesolar cells seemed to be related to the change in the polymer morphology according to the concentration of AgNPsintroduced. These findings suggested the importance of uniform dispersion of plasmonic metal nanoparticles and theirblending concentration conditions in order to boost the solar cell performance.

페롭스카이트 촉매와 Mo, Bi를 기본으로 하는 복합 산화물 촉매를 이용하여 천연가스의 주성분인 메탄의 부분산화를 통하여 메탄올을 직접 합성하였다. 페롭스카이트(ABO₃) 촉매는 A 및 B site 성분을 변화시키면서 사과산법으로 제조하였으며, Mo, Bi를 기본으로 하는 3성분계 복합 산화물 촉매는 공침법으로 제조하여 반응특성을 살펴보았다. 페롭스카이트 촉매에서 A site에 알칼리 금속인 Sr을, B site에 전이금속인 Cr을 도입한 SrCrO₃ 촉매가 400℃에서 메탄올 선택도 11%로 가장 우수한 결과를 보였다. Mo, Bi를 기본으로 하는 3성분계 복합 산화물 촉매의 경우 모든 촉매에서 메탄 전환율에는 큰 차이를 보이지 않았으며, Cr을 첨가한 Mo-Bi-Cr 복합 산화물 촉매가 400℃에서 메탄올 선택도 15.3% 로 가장 우수한 결과를 나타냈다. 3성분계 복합 산화물 촉매에서 촉매의 활성과 메탄올 선택도는 촉매의 표면적에 정비례하였다.

화학살충제, 화학비료를 사용하지 않는 농가에서 다양한 해충에 의한 피해가 증 가하여 구기자의 친환경 농법에 어려움을 주고 있다. 본 연구는 충청남도 청양군 일 원의 친환경 구기자 재배지 4 농가를 선정하여 2012년 5월부터 2013 9월 하순까지 2년간 해충의 발생상을 조사하였으며, 친환경재배를 위한 구기자의 작기에 따라 발생하는 주요 해충의 생태조사를 통하여 방제 방법을 마련하고 주요해충에 대하 여 5가지 친환경제제를 선발하여 방제효과를 확인하였다. 그 결과 구기자나무의 초엽기인 5월 하순과 6월 초순에는 복숭아혹진딧물(Myzus persicae)이 피해가 심 하며, 6월 중순부터는 열점박이잎벌레(Lema decempunctata)의 피해가 심하고, 구기자혹응애(Eriophys macrodonis), 큰이십팔점박이무당벌레(Henosepilachna vigintioctomaculata), 뿔나방류 (Hedma spp.)의 피해는 연중 계속되었다. 열매가 열리는 7월 하순부터는 갈색날개노린재(Plautia stali)와 썩덩나무노린재(Halyomorpba balys)등 노린재류의 피해가 점차 증가하게 된다. 구기자의 주요 해충인 복숭아혹 진딧물, 열점박이잎벌레, 구기자혹응애에 대한 친환경제제의 효과에서는 복숭아 혹진딧물 과 열점박이잎벌레의 경우 고삼과 멀구슬이 혼합된 제제에서 각각 97.6%, 46.8%의 방제가를 보여주며 다른 제제에 비해 효과가 우수하였으며 혹응 애의 경우 고삼과 멀구슬나무, 양명아주 식물추출물이 혼합된 제제에서 낮은 혹형 성률을 보였다.

We report the effect of the chain length of carboxylic acid on the photoluminescence(PL) of /ZnS nanocrystals. /ZnS nanocrystals with emission wavelength ranging from 566 nm through 583 nm were synthesized with zinc acetate and carboxylic acids with various chain length. In this study, /ZnS nanocrystals prepared using long chain carboxylic acid showed more improved PL intensity. The origin of strong photoluminescence of the nanocrystals prepared with zinc acetate and long chain carboxylic acid was ascribed to improved size distribution due to strong reactivity between long chain carboxylic acid and zinc acetate.

This Study constructs a dashboard system to synthetically and systematically monitor national R&D information based on data warehouse Managing the national R&D statistics and trend is important since it provides data for policies and decision making for n

The thermoluminescent phosphors of LiYSiO4 containing rare earth metal(La) dopants of 1 wt.%5 wt.% were prepared, and their TL characteristics have been investigated as a function of parameters such as the doping level and the heating rate. The grain size and cooling temperature of the highly sensitive LiYSiO4: La phosphors have been investigated. The glow curve of LiYSiO4: La has two peaks (P1, P2), and the peak height ratio of the two peaks is called P2/P1; here, the main peak is P2. Experimental results indicate that the peak height ratios of the glow curve for LiYSiO4: La are clearly correlated with the grain size and cooling temperature. The maximum P2/P1 ratio 3.25, the maximum sensitivity was observed for a grain size between 100-150 μm. The intensity of the TL peak of the phosphors was linearly proportion to the dose of X-rays.

Recently, metal molding has become essential not only for automobile parts, but also mass production, and has greatly influenced production costs as well as the quality of products. Its surface has been treated by carburizing, nitriding and induction hardening, but these existing treatments cause considerable deformation and increase the expense of postprocessing after treatment; furthermore, these treatments cannot be easily applied to parts that requiring the hardening of only a certain section. This is because the treatment cannot heat the material homogeneously, nor can it heat all of it. Laser surface treatment was developed to overcome these disadvantages, and, when the laser beam is irradiated on the surface and laser speed is appropriate, the laser focal position is rapidly heated and the thermal energy of surface penetrates the material after irradiation, finally imbuing it with a new mechanical characteristic by the process of self-quenching. This research estimates the material characteristic after efficient and functional surface treatment using HPDL, which is more efficient than the existing CW Nd:YAG laser heat source. To estimate this, microstructural changes and hardness characteristics of three parts (the surface treatment part, heat affect zone, and parental material) are observed with the change of laser beam speed and surface temperature. Moreover, the depth of the hardened area is observed with the change of the laser beam speed and temperature.

Ga-MFI was synthesized by a hydrothermal process at atmospheric pressure. The effect of mole ratios of reactants on crystallization was also investigated thoroughly. The characteristics of synthesized Ga-MFI was compared with ZSM-5. The synthesis of Ga-MFI was carried out with five different mole-compositions of _aSiO2-_bGa2O3-_cNa2O-_dTPA2o-_eH2O. The synthesized Ga-MFI and ZSM-5 were characterized by XRD and FT-IR. The inorganic cation (Na+) and water played an important role in crystallinity and the organic cation (TPA+) as a template played a great influence on yields. With the increase in the amount of Ga3+, crystallization time was increased. With a fixed SiO2/Ga2O3 ratio of 400, the optimum reaction condition was obtained at H2O/SiO2=30~35, Na2O/SiO2=0.5~0.6, and TPA2O/Na2O=1~1.25. In these cases, the crystallinity and yield were more than 95% and 90%, respectively. By comparing IR spectrum of Ga-MFI with those of ZSM-5 and silicalite, it was found that Ga-MFI showed a unique peak at 970 cm-1, which may be used to identify Ga-MFI from ZSM-5 and silicalite.

Synthesis gas is a high valued compound as a basic chemicals at various chemical processes. Synthesis gas is mainly produced commercially by a steam reforming process. However, the process is highly endothermic so that the process is very energy-consuming process. Thus, this study was carried out to produce synthesis gas by the partial oxidation of methane to decrease the energy cost. The effects of reaction temperature and flow rate of reactants on the methane conversion, product selectivity, product ratio, and carbon deposition were investigated with 13wt% Ni/MgO catalyst in a fluidized bed reactor. With the fluidized bed reactor, CH4 conversion was 91%, and Hz and CO selectivities were both 98% at 850℃ and total flow rate of 100 mL/min. These values were higher than those of fixed bed reactor. From this result, we found that with the use of the fluidized bed reactor it was possible to avoid the disadvantage of fixed bed reactor (explosion) and increase the productivity of synthesis gas.