• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2006.06a
• /
• pp.251-252
• /
• 2006

원자력발전소는 기체폐기물의 90% 이상을 계획예방정비기간 중에 방출한다. 기체 폐기물 방출은 filter를 거치지 않고 대량 방출하는 고체적 방출과,filter를 거쳐 방출하는 저체적 방출이 있다. 고체적 방출은 방출농도계수가 5842, 저체적 방출은 계수가 183052로 이 이하로 방출만 하면 발전소제한구역(EPB Emergency Planning Zone)에서의 법적허용치 농도 ECL(environmental Control Limit)를 초과하지 않게 된다. 원전에서는 현재 기체방출 시 이 기준치(농도계수)의 1/10을 자체관리 기준치로 하여 적용하고 있다. 실제 울진3호기 4차O/H 시 그 실적을 파악해 본 결과 고체적 방출 시 방출농도계수가 최대 312, 저체적 방출 시는 최대 707을 넘지 않아 허용방출 농도계수와 비교하면 비교가 되지 않을 정도로 낮게 방출하였음을 확인하였다

• Proceedings of the Korean Nuclear Society Conference
• /
• 1996.05c
• /
• pp.519-525
• /
• 1996

원자력발전소에서 발생하는 중·저준위 폐기물의 처분에 있어 안전성을 확보하기 위하여 폐기물내의 방사성물질의 이력 및 특성을 파악하여야 한다. 본 연구에서는 발전소에서 주기적으로 측정하는 냉각수내 핵종농도와 정화장치별 제염계수를 이용하여 방사성폐기물내의 핵종농도를 예측하였다. 본 방법은 순간제염계수 계산을 통하여 발전소 운전상황 변화를 반영하였으며, 최종정화장치 후단부 방출량을 통한 검증에 있어 평균제염계수를 사용한 경우보다 정확한 핵종누적량을 예측하였다.

• Analytical Science and Technology
• /
• v.22 no.4
• /
• pp.307-312
• /
• 2009

A spectrofluorimetric methods has been developed for the determination of carbaryl in an aqueous solution. The effects of excitation wavelength, concentration of surfactant, concentration of ethanol as cosurfactant and emission wavelength on the fluorescence intensity were investigated to find the optimum experimental conditions to determine carbaryl. The emission intensity of the carbayl was increased with addition of sodium dodecyl sulfate (SDS) as a surfactant. The emission intensity of the carbaryl was further increased with addition of ethanol as a co-surfactant. The optimum conditions were 281 nm for excitation wavelength, $1.0{\times}10^{-2}mol/L$ SDS, 20% (v/v) ethanol and 349 nm for emission wavelength. Under the optimum conditions, the emission intensity increased with the carbaryl concentration in the range of $5{\times}10^{-7}$ to $1.0{\times}10^{-4}mol/L$ with a detection limit ($3{\sigma}$) of $1.1{\times}10^{-8}mol/L$. The resulting correlation coefficient of the working curve was 0.9996.

• Analytical Science and Technology
• /
• v.22 no.3
• /
• pp.191-200
• /
• 2009

The aim of this study was to evaluate and establish of emission test method for liquid phase building materials such as paint, adhesive, sealant by emission cell. A small-scale emission chamber and emission cell were used to evaluate emission of TVOC from paint, adhesive, sealant. The quantity of TVOC emission were measured by a gas chromatography/mass spectrometry (GC/MS). Background concentration of TVOC was below $10{\mu}g/m^3$ in the emission chamber and cell. Air tightness and recovery in chamber and cell showed good results. The recovery of thermal desorber for toluene and n-dodecane were about 120%. The repeatability of response factor and retention time in GC/MS below 30%. The method detection limit of VOCs ranged 0.04~8.82 ng. The concentration of TVOC emission using emission cell was 1.35~1.41 times higher than emission chamber. The correlation of TVOC emission using chamber and cell method was significantly high (r=0.91~0.97).

• Korean Journal of Optics and Photonics
• /
• v.8 no.1
• /
• pp.42-46
• /
• 1997

In order to acquire the fluorescence burst signals emitted from single dye molecules that pass through a detection space defined by a confocal microscope, a computer-interfaced photon counter has been fabricated. The maximum count rate is about 80 MHz, which is limited by the counter devices used. Using both the operating computer program written by BASIC and the 486 PC computer, the minimum bin-width of 25 $mutextrm{s}$ has been achieved. The characteristics of fluorescence burst signals emitted from JA22 molecules at about 1$\times$$10^{-11}$m mol/L in ethylene glycol are discussed briefly.

• Korean Journal of Crystallography
• /
• v.10 no.1
• /
• pp.76-82
• /
• 1999

융액인상법에 의하여 Garnet 구조내 결정학적 8면체 및 4면체의 양이온 자리에 전하 보상이온 Mg2+, 구조 수식이온 Sc3+ 및 laser 활성이온 Cr4+을 다양한 농도로 주입한 융액으로부터 Cr4+:YAG 단결정을 성장하고, 주입된 불순이온이 흡수계수에 미치는 영향을 규명하였다. 양질의 단결정을 성장하기 위한 인상속도와 회전속도는 각각 1.5 mm/h와 10 rmp이었으며, Cr4+:YAG 단결정은 <111> 방위로 성장하였다. 성장된 결정의 결정구조 동정 및 결정격자 상수를 측정하고, 1.064 ㎛에서의 결정화분율에 따른 흡수계수, 형광방출 스펙트럼, 유효편석계수(keff)를 보고하였다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.8
• /
• pp.3572-3578
• /
• 2011

In Positron Emission Tomography Computed Tomography, Standardized Uptake Value(SUV)is most generally used to discern tumors. However, SUV may be influenced other factors. In this study, experiment was conducted distrotion in image and change in SUV according to substance with GEMINI TF PET/CT of Philips.. SUV for materials resulted in 1.8 for stainless, 1.4 for stent, 2.4 for iodine contrast medium, 2.6 for Barium Sulfate, 1.6 for Gypsum, and 1.4 for paraffin respectively. The distortion of image was remarkable for the iodine contrast medium and Barium Sulfate. For the barium sulfate, the higher the density, the larger the distrotion of the images. As a result of test, it appeared that the metallic substance whose atomic number is low and contrast medium whose concentration is low didn't affect the distortion in image and the change in SUV. However, it tis necessary to minimize distortion in image and change in SUV, by removing the metallic substance and checking if there are contrast mdeium or before examination.

• Polymer(Korea)
• /
• v.34 no.4
• /
• pp.333-340
• /
• 2010

Zaltoprofen, a propionic acid derivative non-steroidal anti-inflammatory drug (NSAID), is known to have powerful inhibitory effects on acute, subacute and chronic inflammation. We developed poly(lactide-co-glycolide)(PLGA) microspheres loaded with zaltoprofen for sustained controlled delivery using an oil-water solvent evaporation methods by varying PLGA molecular weight and cosurfactant contents. Physicochemical properties and morphology of zaltoprofen-loaded PLGA microspheres were investigated by scanning electron microscope, X-ray diffraction and differential scanning calorimeter. The size of microspheres increased with the molecular weight of PLGA and the content of cosurfactants. The increase of PLGA molecular weight and cosurfactant content decreased the porosity of microspheres, subsequently resulting in the slow drug release. The results demonstrated that the adjustment of PLGA molecular weight and the cosurfactant content allowed us to control the drug release profiles of drug-loaded microspheres.

• Membrane Journal
• /
• v.3 no.2
• /
• pp.70-78
• /
• 1993

The permeation of insulin was conducted through glucose oxidase(GOD) immobilized composite membrane composed of poly(vinyl akohol)/chitosan blend and porous polyamide membrane. The permeation coefficient of insulin through GOD-immobilized membrane was in the order of $10^{-6}{\sim}10^{-7}\textrm{cm}^3cm/\textrm{cm}^2sec$. The sensitivity of the composite membrane to the glucose concentration was high in a low glucose concentration resulting from the oxygen depletion from the membrane. The permeation of insulin through composite membrane made of PVA/chitosan and porous polyamide membrane was changed by pH and glucose concentration. The permeability was progressively increasing with the glucose concentration at least up to 500mg%.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.3
• /
• pp.242-246
• /
• 2002

Growth and tetraspore release pattern of lithophyllum yessoense (Rhodophyta, Corallinaceae) were investigated from March 2000 to July 2001. Pinkish tetraspores were 40.2 $\pm$ 0.4 $\mu$m in diameter. After release, tetraspores attached on substrate shortly. Culture conditions were five temperatures (5, 10, 15, 20, 25^{\circ}C), four irradiances (0, 20, 50, 100 $\mu$mol${\cdot}m^{-2}$${\cdot}s^{-1}$) and six salinities (0, 9, 17, 25, 34, 43 ppt). Maximum growth of gametophyte was occurred at $20^{\circ}C$, $20{\mu}mol\;m^{-2}$${\cdot}s^{-1}$, 16: 8h (L:D) and 34 put. Maximum relative growth rate was 0.1232 at $20^{\circ}C$. The amount of tetraspore release showed maximum at September as 266 cells per crust area ($cm^2$), and tetraspores did not release from January to March.