• Title/Summary/Keyword: chemical variation

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Studies on the blood chemical properties in racehorses II. Blood chemical values (경주마(競走馬)의 혈액화학성상(血液化學性狀)에 관한 연구 II. 혈액화학치(血液化學値))

  • Kang, Chung-boo
    • Korean Journal of Veterinary Research
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    • v.28 no.2
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    • pp.307-310
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    • 1988
  • This experiment was carried out to provide the data of blood chemistry in use of application to clinical diagnosis in racehorses. Blood was collected from 30 racehorses(♀ 17, ♂ 13). Calcium, inorganic phosphorus, blood glucose, blood urea nitrogen, cholesterol, bilirubin, fibrinogen and ketone body in serum were analyzed as follows. 1. The values of calcium and inorganic phosphorus were maintained a certain level without much variation regardless of sex and species, Ca/P ratio was in the range of 3.13~3.35. 2. The value of blood glucose was 60 mg/100ml, Age and sex of racehorses make no difference in the value. 3. The value of blood urea nitrogen and total cholesterol showed a tendency to increase according to the age. Total cholesterol value was somewhat higher in male than in female. 4. The value of total bilirubin showed a tendency to increase according to the age. There was no difference between sexes in the value. 5. The value of fibrinogen showed no apparent difference with age and sex. 6. Ketone body was negative in all of the cases. 7. There was no variation in the species of the racehorses.

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Determination of Water Content in Ethanol by Miniaturized Near-Infrared (NIR) System

  • Cho, Soo-Hwa;Chung, Hoe-Il;Woo, Young-Ah;Kim, Hyo-Jin
    • Bulletin of the Korean Chemical Society
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    • v.26 no.1
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    • pp.115-118
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    • 2005
  • The miniaturized NIR (Near-infrared) spectrometer has been utilized for the determination of water content (1-19% range) in ethanol that is the most popular organic solvent in pharmaceutical industries. It has many potential capabilities that can replace the conventional analyzers especially for the on-line measurement since it is compact, versatile and cost-effective. By using two dimensional (2D) correlation spectroscopy, it was preliminarily investigated to find any unforeseen spectral distortion among the spectra collected from the miniaturized spectrometer. The 2D study revealed that the spectral variation clearly followed the variation of water concentration without any spectral distortion or abnormality. PLS (Partial Least Squares) was employed to build the calibration model and the resulting prediction performance was acceptable and stable over several days. Even though the miniaturized NIR system was evaluated to fairly simple chemical matrix, the overall study demonstrates the sufficient feasibility for diverse practical and industrial applications.

Flow and heat transfer in a thermal CVD for carbon nanotubes according to variation of the inlet and outlet areas (유입.유출구 크기 변화에 따른 CNT용 CVD 장비 내의 열 및 유동해석)

  • Ha, Da-Som;Jang, Young-Woon;Kim, Jong-Seok;Yoon, Suk-Bum;Im, Ik-Tae
    • Journal of the Semiconductor & Display Technology
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    • v.10 no.4
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    • pp.119-124
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    • 2011
  • Flow and temperature field in reactors are important factors for design of thermal chemical vapor deposition system to grow carbon nanotubes. In this study, effects of the variations of the inlet and outlet areas of the CVD reactor to the flow characteristics and temperature field are numerically analyzed. High temperature of the gas in the entrance region is obtained with slow gas speed resulted from the enlarged inlet area. Variation of the exit area has little effects on the flow field and temperature in the reactor. However the largest area among considered cases gives the highest gas temperature though the differences are small.

Variation of chemical Composition and Relative migration of major Elements in the weathering of Baeg-Gu Granite (백구화강암(白鷗花崗巖)의 풍화(風化)에 따른 화학조성(化學組成)의 변화(變化)와 주요원소(主要元素)의 상대적(相對的) 이동(移動))

  • Nam, Ki Sang
    • Economic and Environmental Geology
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    • v.7 no.4
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    • pp.175-184
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    • 1974
  • Weathering of granites has a great geochemical significance, because of their chemical stability near the earth surface which is more pronounced than in most other rocks. The author intended to observe the relative mobility of major elements in weathering process of the granite, distributed on outskirts of Iri city Jeolla-bugdo, Korea. He analysed fresh granites and weathered ones from the Baeg-Gu granite mass and obtained following conclusions in the triangle-diagrams and the oxidized variation diagrams of the samples. 1) The increasing phenomena of $H_2O$ was observed clearly in early and late stages of weathering process. 2) The early stage of weathering is commenced by physical weathering and followed by chemical weathering. 3) The ratio of $FeO/Fe_2O_3$, FeO/MgO, and $SiO_2/Al_2O_3$ decreased uniformly from early to late stage of weathering processes. 4) It was proved that weathering potential of granite was larger than that of basaltic rock. 5) The order of mobility in major elements was Ca, Na and K

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Correlation between the Potential Barrier and Variation of Temperature on SiOC thin film (탄소 주입 실리콘 산화 절연박막에서 전위장벽과 온도 변화에 대한 상관성)

  • Oh, Teresa
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.12
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    • pp.2247-2252
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    • 2008
  • The SiOC films as the carbon doped silicon oxide film were prepared with the variation of flow rater ratios by plasma enhanced chemical vapor deposition. The samples were analyzed by the fourier transform infrared spectroscopy, I-V measurement and scanning electron microscopy. The samples were shown the chemical shift according to the flow rate ratios, and the grain did not formed at the sample with hybrid properties. The leakage currents decreased according to the increasing of the substrate temperature at the sample with hybrid properties, but the potential barrier increased.

A Study on Settling Properties of Fine-Cohesive Sediments in Keum Estuary (금강 하구역 미세-점착성 퇴적물의 침강특성에 관한 연구)

  • Ryu Hong-Ryul;Chun Min-Chul;Hwang Kyu-Nam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.18 no.3
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    • pp.251-261
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    • 2006
  • The purpose of this study is to quantitatively estimate the settling property for fine-cohesive sediments in Keum Estuary and to evaluate the spatial variation by analyzing and comparing the local and seasonal variation of the settling properties in Keum Estuary with that of the settling properties in the other sites. After the spatial variation of physico-chemical properties such grain size distribution, the percentage of organic contents, mineralogical composition etc is investigated through experiments and analyses, interrelation between the physico-chemical properties and settling velocities and effect that the physico-chemical properties have on the quantitative variation of settling velocities were also analyzed in this study. Experimental results of settling tests shows that settling velocities of Keum Estuary mud vary in the range of two orders of magnitude (from 0.01 to 1mm/sec) over the corresponding concentration range of 0.1 to 80 g/L, and a feature of settling velocity profile is quite different in quantity as compared to those of previous studies with mud of other regions: Saemankuem, Tampa Bay, Sevem Estuary and lake Okeechobee. However, their local and seasonal variabilities within Keum Estuary appear to be insignificant.

A Study on the Deposit Uniformity and Profile of Cu Electroplated in Miniaturized, Laboratory-Scale Through Mask Plating Cell for Printed Circuit Board (PCBs) Fabrication

  • Cho, Sung Ki;Kim, Jae Jeong
    • Korean Chemical Engineering Research
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    • v.54 no.1
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    • pp.108-113
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    • 2016
  • A miniaturized lab-scale Cu plating cell for the metallization of electronic devices was fabricated and its deposit uniformity and profile were investigated. The plating cell was composed of a polypropylene bath, an electrolyte ejection nozzle which is connected to a circulation pump. In deposit uniformity evaluation, thicker deposit was found on the bottom and sides of substrate, indicating the spatial variation of deposit thickness was governed by the tertiary current distribution which is related to $Cu^{2+}$ transport. The surface morphology of Cu deposit inside photo-resist pattern was controlled by organic additives in the electrolyte as it led to the flatter top surface compared to convex surface which was observed in the deposit grown without organic additives.

Effect of Poly(butyl acrylate)-Poly(methyl methacrylate) Rubber Particle Texture on the Toughening Behavior of Poly(methyl methacrylate)

  • Chung, Jae-Sik;Park, Kyung-Ran;Wu, Jong-Pyo;Han, Chang-Sun;Lee, Chan-Hong
    • Macromolecular Research
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    • v.9 no.2
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    • pp.122-128
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    • 2001
  • Monodisperse composite latex particles with size of ca. 300 nm, which consist ofn-butyl acrylate as a soft phase and methyl methacrylate as a hard phase with different morphology, were synthesized by seeded multi-stage emulsion polymerization. Three types of composite latex particles including random-, core/shell-, and gradient-type particles were obtained by using different monomer feeding methods during semi-batch emulsion polymerization. Effect of poly(butyl acrylate)-poly(methyl methacrylate) rubber particle morphology on the mechanical and rheological properties of rubber toughened poly(methyl methacrylate) was investigated. Among three different rubber particles, the gradient-type rubber particle showed better toughening effect than others. No significant variation of rheological property of poly(methyl methacrylate)/rubber blends was observed for the different rubber particle morphology.

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The Optimization of the Production Ratio by the Mean-variance Analysis of the Chemical Products Prices (화학 제품 가격의 변동으로 인한 위험을 최소화하며 수익을 극대화하기 위한 생산 비율 최적화에 관한 연구)

  • Park, Jeong-Ho;Park, Sun-Won
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.12
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    • pp.1169-1172
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    • 2006
  • The prices of chemical products are fluctuated by several factors. The chemical companies can't predict and be ready to all of these changes, so they are exposed to the risk of a profit fluctuation. But they can reduce this risk by making a well-diversified product portfolio. This problem can be thought as the optimization of the product portfolio. We assume that the profits come from the 'spread' between a naphtha and a chemical product. We calculate a mean and a variation of each spread and develop an automatic module to calculate the optimal portion of each product. The theory is based on the Markowitz portfolio management. It maximizes the expected return while minimizing the volatility. At last we draw an investment selection curve to compare each alternative and to demonstrate the superiority. And we suggest that an investment selection curve can be a decision-making tool.

Electrolyte Effect on the Particle Characteristics Prepared by Soap-Free Emulsion Polymerization

  • Han, Seung-Tak;Lee, Kang-Seok;Shim, Sang-Eun;Saikia, Prakash J.;Choe, Soon-Ja;Cheong, In-Woo
    • Macromolecular Research
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    • v.15 no.5
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    • pp.403-411
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    • 2007
  • Monodisperse micron-sized polystyrene (PS) spheres were successfully obtained using a single stage soap-free emulsion method in aqueous media mixed with ethanol (co-solvent) containing NaCI as the electrolyte. The optimum conditions for preparing the monodisperse PS microspheres, using soap-free emulsion polymerization in a water/ethanol mixture with an electrolyte, were studied. The presence of the co-solvent and electrolyte controlled the particle dispersion stability during the polymerization. The microspheres formed using PS, with a weight-average diameter of $2.6{\mu}m$, coefficient of variation of 5.3% and zeta potential of -15.1 eV, were successfully obtained in the presence of 0.1 wt% NaCI, 10 wt% monomer, 0.1 wt% initiator and 95/5 (g/g) of a water/ethanol mixture reacted at $70^{\circ}C$ for 24 h.