• 한국어병학회지
• /
• 제36권2호
• /
• pp.293-302
• /
• 2023

본 연구는 구피(Poecilia reticulata)에서 oxolinic acid (OA), neomycin-oxytetracycline 복합제(NEO-OTC) 및 florfenicol (FF)의 급성독성을 96시간 동안 약욕투여하여 96h-LC₅₀으로 평가하였다. 또한 활성성분 함량이 2-4%로 낮은 상업용 제제의 급성독성을 평가하여 표준품과 비교하고, 에로모나스병에 대한 치료 효능을 평가하였다. 구피에서의 급성독성은 NEO-OTC이 126.08 mg/L로 가장 높았다. OA는 염의 형태에 따라서 급성독성의 결과가 크게 상이하였다. Oxolinic acid 형태는 최고 농도인 1,000 mg/L에서도 모든 개체가 생존한 반면, 수산용의약품으로 사용되는 sodium염 형태는 96h-LC₅₀이 504.61 mg/L로 도출되었다. 특히 모든 폐사는 OA가 용출되기 전인 24시간 이내에 발생하였다. FF의 급성독성은 매우 낮아 96h-LC₅₀이 1,000 mg/L 이상으로 도출되었다. 본 연구에서 평가한 OA 및 NEO-OTC 상업용 제제는 산제 형태로, FF 상업용 제제는 액제 형태로 사용되었다. 부형제는 산제의 경우 glucose 및 lactose hydrate가 함량의 대부분을 차지하며, powdered corn syrup이 소량 첨가되었다. 액제의 경우 propylene glycol이 함량의 대부분을 차지하며, N-methylpyrrolidone, polysorbate 80, butylated hydroxy toluene이 소량 첨가되었다. OA 및 NEO-OTC 상업용 제제의 급성독성은 표준품과 큰 차이를 보이지 않았지만, FF 상업용 제제는 현저하게 급성독성이 증가하였고, 그 이유는 아마도 상업용 제제에 함유된 유기용매나 용해보조제가 독성을 강화시키는 것으로 추측된다. OA, NEO-OTC 및 FF 약욕투여는 단시간(2시간) 약욕투여시 각각 50 mg/L, 100 mg/L 및 15 mg/L 농도로, 장시간(24시간) 약욕투여시 각각 25 mg/L, 50 mg/L 및 7.5 mg/L 농도로 에로모나스병을 유의미하게 방어하였다. 이 결과는 급성독성이 발견되지 않는 용량 범위에서 에로모나스병 치료를 위한 용량 및 시간을 제시하였으며, 낮은 농도의 항생제를 포함한 액상제제가 부분적으로 독성을 증가시키기는 하지만 효과적으로 관상어의 질병을 치료하기에는 문제가 없음을 의미한다.

• 한국환경과학회지
• /
• 제24권5호
• /
• pp.615-622
• /
• 2015

East Asia is characterized by anthropogenic emissions resulting from the large population and fast economic growth of this region. Since the prevailing wind is westerly and northwesterly, emissions from Ul-jin can be expected to contribute to acidic deposition increase in downwind direction. Aerosols collected at the near coast site, Uljin geun, gyungbook and were analyzed for $NH_4{^+}$, $Mg^{2+}$, $Na^+$, $Ca^{2+}$, $Cl^-$, $SO_4{^{2-}}$, and $NO_3{^-}$ from Aug. 2012 to Feb. 2013. The seasonal averaged aerosol concentration showed the highest potassium and calcium ion in winter and the highest ammonium ion due to a meadow and high solar intensity in summer. Sodium and chloride ion showed the same ratio all seasons and sulfate and nitrate species showed the maximum value in winter Chemical components of aerosols collected at the near coast site, Uljin geun, gyungbook were lower by 16 to 73% than those collected at other similar environment site such as kanghwa, yangyang. Comparing air quality data at the near coast site, Uljin geun, gyungbook, There was found that Uljin coast site is less influenced by the sea salts(potassium, magnesium, calcium) and nss-$SO_4{^{2-}}$ percentage is 3~13% higher than similar condition site.

• 약학회지
• /
• 제16권3호
• /
• pp.113-120
• /
• 1972

The last decade of this centry is now the accepted birth date of that sub-discipline of pharmacy that is now called 'biopharmceutics'. Wagner defines biopharmaceutics 'as the study of the influence of fomulation on the therapeutic activity of a drug product.' More specifically, he states that biopharmaceutics encompasses the study of the relationship between the nature and intensity of the biological effects observed in animals or man and the following factors: 1. The nature of the form of the drug (ester, salt, complex, etc). 2. The physical state, particle size, and surface area. 3. Presence or absence of adjuvants with the drug. 4. The type of dosage form in which the drug is administered. 5. The pharmaceutical process (es) used to make the dosage form. The philosophy inherent in this definition has revolutionized our thinking with respect to product development, quality control, and to the practice of pharmacy itself. Althoughthe the emphasis herein will be on quality control, the interrelationship between this and the other areas of pharmacy will be evident. The principles of quality control dictate that a wide variety of techniques be used to evaluate the quality of a dosage form. Since quality must be built into a dosage form, the pharmaceutical scientist begins the process at the research stage, continues it during the production stage, and ends it by applying the tests and procedures established by parmacopeial commissions. These stages are usually separate and distinct and, because of this, product quality has become synonymous with compliance with pharmacopeial specifications.

• 한국표면공학회지
• /
• 제31권6호
• /
• pp.359-370
• /
• 1998

TiAl-based intermetallic compounds were electro-bornizel in the mixture of $Na_2B_4O_7$, KCL and LiCl in the termetature rage between 850 and $1000^{\circ}C$for various times (1-5 hours)under the fixed current density of 0.5 A/$cm^2$. The optimized composition of electrolyte in this work was decided to be 76.9 wt% $Na_2B_4O_7$-19.2 wt.%(0.7KCl-0.3LiCl) -3.9 wt.% al. The samples with boronized layer were investigated by SEM, XRD and EDS. The surface micro-hardness of boronized TiAl was also evaluated using Micro Vickers Hardness Tester. The sample, boronized at $900^{\circ}C$ for 4 hours in the above composition of electrolyte under the current density of 0.5 A/$\textrm{cm}^2$, has about 36$\mu\textrm{m}$ think layer on the surface, and its surface micro-hardness was measured to be 1263 Hv. From the results of SEM, XRD and EDS, the layer consisted of $TiB_2$ sublayer and Al-oxide sub layer. Al-depleted layer below the Al-oxide sudlayer was also detected. The activation energy for formation of boronized layer in this study was calculated as 178 Kcal/moleK.

• 한국기계가공학회지
• /
• 제8권2호
• /
• pp.3-9
• /
• 2009

When washing machine is rotated in the laundry, it tends to lean toward one side. This tendency causes a serious vibration. The balance of washing machine plays an important role in order to reduce the vibration by injecting the sand or the salt water into the balance of washing machine. The hot plate welder is used to prevent from outflow of contents. The hot plate welder brings about many problems which is concerned with accidents. The direction recognition and location information of the balance are required in this system. In this paper, the recognition direction of balance in washing machine using machine vision system is studied. The template matching algorithm compares sub-image with original image acquired in real-time to obtain a center point of balance image. The mid points and the edges of balance are estimated by the edge detection and gauging algorithms. The data acquired by these results is used for recognition direction of balance. The automation software for image processing is developed by using LabVIEW.

• 한국염색가공학회지
• /
• 제13권5호
• /
• pp.24-24
• /
• 2001

Kinetics and mechanism for alkaline hydrolysis of C. I. Disperse Blue 79(B-79) which is 4-N, N-diacetoxyethyl-2-acylamino-5-ethoxy -2′-bromo-4′,6′-dinitroazobenzene were investigated. The color strength of B-79 in acetone/water solutions of various NaOH concentrations decreased continuously. The hydrolysis rate of B-79 increased with increasing alkali concentration and appeared following first order reaction. The observed rate constants for various concentrations of B-79 showed similar values, and B-79 was hydrolyzed by first order reaction for dye concentration. Therefore, it was confirmed that the overall reaction follow second order kinetics and proceed via S/sub n/2 reaction. From the study on kinetics and spectrometric analysis, it was proposed that the rate determining step of the hydrolysis reaction of B-79 is the nucleophilic substitution reaction - that is the reaction of the rapid attack of $OH^{-}$ on the carbon atom, which is in acceptor ring, adjacent to azo group to break the C-N bond. And it was also found that the final hydrolysis products of B-79 include both the acceptor ring in the form of sodium salt and the donor ring possessing 4-N,N-dihydroxyethyl group converted from 4-N,N-diacetoxyethyl group.

• 대한수의학회지
• /
• 제47권3호
• /
• pp.299-302
• /
• 2007

Neoheterobothrium hirame (N. hirame) is a large blood-feed gill-worm infecting the highly prized olive flounder. The present study was reported the occurrence and elimination of Neoheterobothrium infection from young cultured oliver flounder in the western coast of Korea. Flounder (weight 18-25 g, length 10-15 cm) were obtained from a cultured farm at Taean of Korea at May 2006. A lot of flounder died with serious anemia. We isolated N. hirame from the buccal cavity wall of dead flounder. Adult parasites were 5-15 mm in total length, with 4 pairs of clamps on the pedunculated haptor and isthmus region embedded in host tissue, while immature and sub-adults were identified the attachment to the gill filaments, rakers and arches with the clamps. All fish with infection were treated with 8% NaCl-supplemented seawater for 1 and 10 min at $22^{\circ}C$, respectively. The significant reduction in mortality (6.7%) was observed among fish treated with 8% salt water for 10 minutes, when compared with that of non-treatment group (100%).

• Bulletin of the Korean Chemical Society
• /
• 제32권6호
• /
• pp.1975-1979
• /
• 2011

The modification of a gas diffusion layer (GDL), a vital component in polymer electrolyte fuel cells, is described here for use in the electrochemical detection of antibody-antigen biosensors. Compared to other substrates (gold foil and graphite), mouse anti-rHBsAg monoclonal antibody immobilized on gold-coated GDL (G-GDL) detected analytes of goat anti-mouse IgG antibody-ALP using a relatively low potential (-0.0021 V vs. Ag/AgCl 3 M NaCl), indicating that undesired by-reactions during electrochemical sensing should be avoided with G-GDL. The dependency of the signal against the concentration of analytes was observed, demonstrating the possibility of quantitative electrochemical biosensors based on G-GDL substrates. When a sandwich method was employed, target antigens of rHBsAg with a concentration as low as 500 ng/mL were clearly measured. The detection limit of rHBsAg was significantly improved to 10 ng/mL when higher concentrations of the 4-aminophenylphosphate monosodium salt (APP) acting on substrates were used for generating a redox-active product. Additionally, it was shown that a BSA blocking layer was essential in improving the detection limit in the G-GDL biosensor.

• International Journal of Safety
• /
• 제4권2호
• /
• pp.24-29
• /
• 2005

An experimental study was presented for extinguishing characteristics of liquid fuel fire by water mist($Dv_{0.99}{\leq}200{\mu}m$) containing potassium acetate and sodium acetate trihydrate. To evaluate the extinguishing performance of water mist containing additives, the evaporation characteristics of a water droplet on a heated surface was examined. The evaporation process was recorded by a charge-coupled-device camera. Also, small-scale extinguishing tests were conducted for n-heptane pool fire in ventilated space. During the experiments, flame temperatures were measured, and concentrations of oxygen and carbon monoxide were analyzed by a combustion gas analyzer. The average evaporation rate of water droplet containing additives was lower than that of pure water at a given surface temperature and decreased with the concentration increase due to the precipitation of salt in the liquid-film and change of surface tension. In case of using additives, the fire extinguishing times was shorter than that of pure water at a given discharge pressure and it was because the momentum of a water droplet containing additives was increased. And also dissociated metal atoms, potassium or sodium, were reacted as a scavenger of the major radical species OH, H which were generated for combustion process. Moreover, at a high pressure of 4 MPa, the fire was extinguished through blowing effect as well as primary extinguishing mechanisms.

• 한국환경과학회지
• /
• 제14권1호
• /
• pp.97-103
• /
• 2005

Because of the toxicity of hexavelant chromium ion, treatments of metallic surface with chromate compounds to retard corrosion are undesirable for safety control in industrial uses and protection of environment. In this study, we investigated several compounds such as inorganic, organic, and polymer materials in order to sub­stitute the chromate conversion treatment on steel sheet. The corrosion property was investigated in a salt spray tester with 3.5 $wt.{\%}\;NaCI\;at\;35^{\circ}C.$ The results showed that the zirconium/silane/polymer triple coatings on the galvanized steel exhibited a significant retardation of corrosion. Although the multicoating system needs a com­plexed processing, we can confirm a possibility of development of a chromate-free chemical conversion treat­ment for galvanized steel sheet.