• Title/Summary/Keyword: Metal excess

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A Measure of Chemical Carcinogenic Activity for Metal Ions (금속이온에 대한 화학발암성의 척도)

  • Byung-Kak Park;Hwhan-Jin Yeo
    • Journal of the Korean Chemical Society
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    • v.29 no.4
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    • pp.341-347
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    • 1985
  • Formation of metal complex is the first step in the many biological actions of metal ions present in the biological systems. In this work the not electron affinity necessary for the formation of such metal complexes has been determined for a series of metal ions. It has been found that excess polarizing strength can be adopted as a measure of electron affinity and trend is the excess polarizing strength is related to Irving-Williams series. Those metal ions having greater than 0.22 in value of excess polarizing strength have been found to show carcinogenicity and other metal ions, which are supposed to be carcinogenic, have shows to have greater than 0. 22 in value of excess polarizing strength, demonstrating that excess polarizing strength could be used to determine if any metal ion possesses carcinogenic activity.

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Study on the Seventy-fifth Question of "Nan-gyeong(Classic of Difficult Issues, 難經)" (난경(難經).칠십오난(七十五難)에 대한 연구)

  • Kim, Hyun-Jung;Kang, Jung-Soo
    • Journal of Korean Medical classics
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    • v.22 no.4
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    • pp.189-198
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    • 2009
  • Considering the opinions of annotators, the remedy about excess of east and deficiency of west from "the seventy-fifth question" can be arranged as follows. "The seventy-fifth question", with "the sixty-ninth question", explains excess and deficiency of mother and son. Abatement of fire and invigoration of water[瀉火補水] in the excess of wood and deficiency of metal[木實金虛] presents a remedy, which has been applied in herbs and medicine application henceforth. "The seventy-fifth question" is a unique theory from " Nan-gyeong(難經)", and does not continue the theory of "Hwangjenaegyeong(黃帝內經)". "The seventy-fifth question" mentions the relationship of excess and deficiency of the five elements and five viscera, but does not mention excess and deficiency of invigoration and abatement of the meridian. Remedy from abatement of fire and invigoration of water[瀉火補水] in the excess of wood and deficiency of metal[木實金虛] is an abnormal, temporary and extraordinary method. This remedy is applied in Saam acupuncture[舍巖鍼] as A-variation form. The process where Son allows excess of mother[子能令母實] and mother allows deficiency of son[母能令子虛] in the abatement of fire and invigoration of water[瀉火補水] is a mechanism, not a remedy. Generation after generation, medical practitioners can be classified into those that claimed abatement of fire and invigoration of water[瀉火補水] because of the relation with excess of liver and deficiency of lung[肝實肺虛], abatement of heart(瀉心) due to the excess of liver(肝實), or invigoration of Eum and abatement of Yang[補陰瀉陽].

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A Study on Reusable Metal Component as Burnable Absorber Through Monte Carlo Depletion Analysis

  • Muth, Boravy;Alrawash, Saed;Park, Chang Je;Kim, Jong Sung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.4
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    • pp.481-496
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    • 2020
  • After nuclear power plants are permanently shut down and decommissioned, the remaining irradiated metal components such as stainless steel, carbon steel, and Inconel can be used as neutron absorber. This study investigates the possibility of reusing these metal components as neutron absorber materials, that is burnable poison. The absorption cross section of the irradiated metals did not lose their chemical properties and performance even if they were irradiated over 40-50 years in the NPPs. To examine the absorption capability of the waste metals, the lattice calculations of WH 17×17 fuel assembly were analyzed. From the results, Inconel-718 significantly hold-down fuel assembly excess reactivity compared to stainless steel 304 and carbon steel because Inconel-718 contains a small amount of boron nuclide. From the results, a 20wt% impurity of boron in irradiated Inconel-718 enhances the excess reactivity suppression. The application of irradiated Inconel-718 as a burnable absorber for SMR core was investigated. The irradiated Inconel-718 impurity with 20wt% of boron content can maintain and suppress the whole core reactivity. We emphasize that the irradiated metal components can be used as burnable absorber materials to control the reactivity of commercial reactor power and small modular reactors.

Catalytic Removal of Nitric Oxide in Oxygen-Rich Exhaust with Methane over Metal Ion-Exchanged Zeolites (금속이온교환 제올라이트 촉매상에서 메탄을 이용한 산소과잉 배출가스중의 NO 제거)

  • 김상환;박정규
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.1
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    • pp.32-44
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    • 2002
  • Selective catalytic reduction of nitric oxide by methane in the presence of excess oxygen was investigated over copper and cobalt ion-exchanged ZSM-5 zeolites. Copper ion-exchanged ZSM-5(Cu-ZSM-5) has the limitations for commercial applications to lean-bum gasoline and diesel engines due to low thermal stability and resistance to water vapor and sulfur dioxide. But cobalt ion-exchanged ESM-5(Co-ZSM-5) is more active at high temperatures and also stable to water vapor and sulfur dioxide for catalytic reduction of nitric oxide by methane. The catalytic activity of Cu-ZSM-5 for NO reduction increases with increasing temperatures, reaches the maximum conversion of 23.0% at 350\"C. and then decreases with higher temperatures. In the meantime catalytic activities of Co-ZSM-5 show the maximum conversion of 25.8% at $500^{\circ}C$ Therefore Co-ZSM-5 catalysts have higher thermal stability at high temperatures. Catalytic activities of both zeolites were remarkably enhanced with the existence of oxygen in the exhaust. It is noted that the catalytic activity of Cu-ZSM-5 decreases with the increasing concentration of methane while the catalytic activity of Co-ZSM-5 decreases with increasing contents of methane in the exhaust. This may imply the existence of different paths of NO reduction by methane in the presence of excess oxygen fur Cu-ZSM-5 and Co-ZSM-5 catalysts. For binary metal ionexchanged ZSM-5, the primary ion-exchanged metal may be masked by secondary ion-exchanged component, which plays the important role for catalytic activities of binary metal ion-exchanged ZSM-5, Therefore CuCo-ZSM-5 catalysts show the similar volcano-shaped curves to Cu-ZSM-5 catalysts between the activity and temperature. It Is interesting that the activities of CoCu-ZSM-5 catalysts indicate almost no dependence on the concentration of methane in the exhaust.aust.

A Study on the Oxidation Behavior of Metal Materials Applicable to Oxidizer Rich Pre-Combustor (산화제 과잉 연소기에 활용 가능한 금속재료의 산화 거동에 관한 연구)

  • Shin, Donghae;Yu, Isang;Shin, Minku;Ko, Youngsung;So, Younseok;Han, Yeoungmin
    • Journal of the Korean Society of Propulsion Engineers
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    • v.23 no.2
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    • pp.118-125
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    • 2019
  • Metals exposed to high temperature/high pressure/oxidant excess environment of an oxygen excess pre-combustor may undergo rapid oxidation. In this study, the test facility to simulate the high temperature/high pressure/oxidant excess environment was constructed and the oxidation resistance evaluation was carried out for various metal materials. As a result, the discoloration of the metallic materials, the change in the surface roughness and the peeling of the metal surface were observed, and the weight change was also observed. The resulst showed that oxidation-resistant coating of a metal material of the combustor is indispensably required, and the use of XM-19, which has the highest content of Cr and Ni, is expected to provide more structural stability.

Efficient Design of BCD-EXCESS 3 Code Converter Using Quantum-Dot Cellular Automata (QCA를 이용한 효율적인 BCD-3초과 코드 변환기 설계)

  • You, Young-Won;Jeon, Jun-Cheol
    • Journal of Advanced Navigation Technology
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    • v.17 no.6
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    • pp.700-704
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    • 2013
  • Quantum-dot cellular automata(QCA) is a new technology and it is an one of the alternative high performance over existing complementary metal-oxide semi-conductor(CMOS). QCA is nanoscale device and ultra-low power consumption compared with transistor-based technologies, and various circuits using QCA technology have been proposed. Binary-coded decimal(BCD), which represents decimal digits in binary, is mainly used in electronic circuits and Microprocessor, and it is comfortable in conversion operation but many data loss. In this paper, we present an BCD-EXCESS 3 Code converter which can be efficiently used for subtraction and half adjust. The proposed scheme has efficiently designed considering space and time complexities and minimization of noise, and it has been simulated and confirmed.

An Equilibrium Analysis to Determine the Speciation of Metals in the Incineration of Waste Containing Chlorine (염소를 함유한 폐기물의 소각시 생성되는 유해 중금속류 결정에 대한 화학 평형 계산)

  • ;;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.12
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    • pp.3372-3381
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    • 1995
  • An equilibrium analysis was carried out to determine principal species of heavy metals in waste incineration and their behaviors with variation of temperature, chlorine concentration, excess air ratio, and C/H ratio. The waste was assumed as a compound of hydrocarbon fuel, chlorine, and metals. Calculated results showed that the most important parameter to determine the principal species was temperature. Chlorine concentration also affected on mole fractions of the principal species. Generally principal species at high temperature were chlorides while there were some metals of which principal species were oxides. At low temperature mole fractions of the principal species increased, but at high temperature mole fractions of some metal species decreased. C/H ratio of the hydrocarbon fuel and excess air ratio had little effect on mole fractions of the metal species, compared to the temperature and chlorine concentration.

Design Modification of the Stamping Die for the Improvement of Surface Quality of the Front End Module Carrier Upper Member (프런트 엔드 모듈 캐리어 어퍼 부재의 면품질 개선을 위한 금형설계 변경)

  • Kim S. H.
    • Transactions of Materials Processing
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    • v.14 no.2 s.74
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    • pp.153-159
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    • 2005
  • Design modification of the stamping die for the upper member of a front end module carrier is carried out in order to improve the surface quality of the final product. The small inferiority induced by wrinkling near the wall of the upper member has been inspected after the draw-forming process. The finite element analysis is pursued with the whole geometry in order to consider the complicated shape. The simulation shows that the excess metal is developed by the irregular contact of the blank the tool and it remains after the final stroke. This paper proposes two guidelines for the modification. One is to add the draw-bead near the critical region in order to increase the draw-in force. The other is to modify the tool shape such as the forming shape at the wall in order to absorb the excess metal before the final stroke. Simulation results show that the proposed guidelines both guarantee the improved surface quality.

A study on mathematical modeling and heat transfer analysis to predict weld bead geometry in horizontal fillet welding (수평필릿용접의 용접부 형상을 예측하기 위한 수학적 모델링 및 열전달 해석에 관한 연구)

  • 문형순;나석주
    • Journal of Welding and Joining
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    • v.14 no.6
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    • pp.58-67
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    • 1996
  • The horizontal filet welding is prevalently used in heavy and ship building industries to join the parts. The phenomena occurring in the horizonal fillet welding process are very complex and highly non-linear, so that its analysis is relatively difficult. Furthermore, various kinds of weld defect such as undercut, overlap, porosity. excess weld metal and incomplete penetration can be induced due to improper welding conditions. Among these defects, undercut, overlap and excess weld metal appear frequently in horizontal filet welding. To achieve a satisfactory weld bead geometry without weld defects, it is necessary to study the effect of welding conditions in the weld bead geometry. For analyzing the weld bead geometry with and without weld defects in horizontal fillet welding, a mathematical model was proposed in conjunction with a two-dimensional heat flow analysis adopted for computing the melting tone in . base metal. The reliability of the proposed model was evaluated through experiments. which showed that the proposed model was very effective for predicting the weld bead shape with or without weld defects in horizontal fillet welding.

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Preparation of 0.9PMN-0.1PT ceramics by sol-gel process (졸-겔법에 의한 0.9PMN-0.1PT 소결체의 제조)

  • 연석주;김종흠;고태석
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.12 no.1
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    • pp.1-6
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    • 2002
  • The preparation of 0.9PMN-0.1PT ceramics by the metal alkoxide method and the effect of excess $Mg(OC_2H_5)_2$, $Pb(CH_3COO)_2{\cdot}3H_2O$ are reported. The excess$ Mg(OC_2H5)_2$ addition signficantly affects the rate of perovskite phase formation in 0.9PMN-0.1PT ceramics. The sample by addition of 5 wt% excess $Mg(OC_2H5)_2$ sintered at $1150^{\circ}C$ for 1 hr obtained perovskite single phase and showed 98% of the theoretical density. The dielectric constant of the pellets sintered at $1150^{\circ}C$ was increased by the addition of 5 wt% excess $Mg(OC_2H_5)_2$ and had a maximum value of 15000 at 1 kHz.