• Title/Summary/Keyword: non-metal

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A Study on the heavy metal contents in the soils and vegetables (중금속에 의한 토양오염과 그 작물함량에 관한 연구)

  • 김명미;고영수
    • Journal of Food Hygiene and Safety
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    • v.1 no.1
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    • pp.51-56
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    • 1986
  • In the particular area the heavy metal concentrations in the soil were determined and compared to the contents in vegetables which were grown on the soil. Simultaneously the degree of contamination was examined. Samples were collected from Chinese cabbage, radish and Altari-mu, together with the soil on which the three kinds of vegetables have grown. The sites of samples collection were Jinguan-sa(non-polluted area) and Sangaedong(polluted area). The contents of cadimium, copper, lead and zinc were determined by means of atomic absorption spectro-photometer. The results obtained were as follows; 1. In soils, the average contents of heavy metal in Jinguan-sa area (Cd; 0.15ppm, Cu; 0.15ppm, Zn; 11.5ppm) were lower than those in sangye-dong(Cd; 0.26ppm, Cu; 13.0ppm, Zn; 17.1ppm). 2. In vegetables, the average have metal contents in Jinguan-sa were cadmium; 0.11ppm, copper; 5.29ppm, zinc; 18.75ppm and the average contents in Sangye-dong were cadmium; 0.16ppm, copper; 6.64ppm, lead; 0.14ppm, zinc; 15.01ppm. 3. The contents of lead showed zero ppm in Jinguan-sa area(soil and vegetables). In vegetables difference in concentration of heavy metals was not observed between reclaimed area and non reclaimed area. Statistical analysis showed that no correlation in the heavy metal concentrations between those in soils and in vegetables.

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Edge-Cracking Behavior of CoCrFeMnNi High-Entropy Alloy During Hot Rolling

  • Won, Jong Woo;Kang, Minju;Kwon, Heoun-Jun;Lim, Ka Ram;Seo, Seong Moon;Na, Young Sang
    • Metals and materials international
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    • v.24 no.6
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    • pp.1432-1437
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    • 2018
  • This work investigated edge-cracking behavior of equiatomic CoCrFeMnNi high-entropy alloy during hot rolling at rolling temperatures $500{\leq}T_R{\leq}1000^{\circ}C$. Edge cracks did not form in the material rolled at $500^{\circ}C$, but widened and deepened into the inside of plate as $T_R$ increased from $500^{\circ}C$. Edge cracks were most severe in the material rolled at $1000^{\circ}C$. Mn-Cr-O type non-metallic inclusion and oxidation were identified as major factors that caused edge cracking. The inclusions near edge region acted as preferential sites for crack formation. Connection between inclusion cracks and surface cracks induced edge cracking. Rolling at $T_R{\geq}600^{\circ}C$ generated distinct inclusion cracks whereas they were not serious at $T_R=500^{\circ}C$, so noticeable edge cracks formed at $T_R{\geq}600^{\circ}C$. At $T_R=1000^{\circ}C$, significant oxidation occurred at the crack surface. This accelerated edge crack penetration by embrittling the crack tip, so severe edge cracking occurred at $T_R=1000^{\circ}C$.

A Study on Cutting Character of Side-rake Angle Adjustment at Non-ferrous Metals in Turning (비철금속의 선삭에서 측면경사각의 변화에 대한 절삭특성에 대한 연구)

  • Jung, Jin-Seo;Jun, Jae-Uhk;Han, Gu-Sang;Seo, Sang-Ha;Ha, Man-Kyung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.2 no.1
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    • pp.39-44
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    • 2003
  • In the present industry, there are necessary to cut not only iron metals but also non-ferrous metals such as aluminum, brass, plastic and wood(Paulownia) therefore it had been made the studies of non-ferrous metals by many scientists. The purpose of this study is to conduct the basic experiment about influencing of the feedrate adjustment and the change of the side rake angle at turning of non-ferrous metals. As the results, the surface roughnesses and Cutting force adjustments were on the decrease with a side-rake angle and feedrate diminution in the case of the plastic, brass, aluminum, and paulownia.

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Influence of Surface Roughness by Feed-rate and Sider-rake Angle at Turning of Non-ferrous Metals (비철금속의 선삭에서 측면경사각과 이송량이 표면 거칠기에 미치는 영향)

  • 전재억;정진서;하만경
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.4
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    • pp.1-6
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    • 2001
  • In the present industry, there are necessary to cut only iron metals but also non-ferrous metals such as aluminum, brass, plastic and wood(Paulownia), therefor it had been made the studies of non-ferrous metals by many scientists. we hope this kind of study will continue. The purpose of this study is to conduct the basic experiment about influencing of the feedrate adjustment and the change of the side rake angle at turning of non-feerous metals. As the results, the surface roughnesses were on the decrease with a side-rake angle and feedrate diminution in the case of the pastic, aluminum, and paulownia.

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A Study on Cutting Character of Side-rake angle Adjustment at Non-ferrous Metals in Turning (비철금속의 선삭에서 측면경사각의 변화에 대한 절삭특성에 대한 연구)

  • 전재억;정진서;권혁준;하만경
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.929-934
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    • 1997
  • In the present industry, there are necessary to cut not only iron metals but also non-ferrous metals such as aluminum, brass, plastic and wood(Paulownia).therefore it had been made the studies of non-ferrous metals by many scientists. we hope this kind of study will continue. The purpose of this study is to conduct the basic experiment about influencing of the feedrate adjustment and the change of the side rake angle at turning of non-ferrous metals. As the results, the surface roughnesses and Cutting force adjustments were on the decrease with a side-rake angle and feedrate diminution in the case of the plastic, brass, aluminum, and paulownia

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Current Status on the Recycling of Domestic Nonferrous Metal Scraps (국내(國內) 비철금속(非鐵金屬) 스크랩 리싸이클링 현황)

  • Park, Hyung-Kyu;Shin, Hee-Duck
    • Resources Recycling
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    • v.18 no.1
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    • pp.52-57
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    • 2009
  • Since there are many kinds of non-ferrous metal, it is difficult to investigate the current status on the recycling of non-ferrous metals. Therefore, the survey is confined to some commercially important non-ferrous metals such as copper, lead, zinc, aluminum, nickel and magnesium in this article. Domestic demand and production in recent years and current status on the recycling of the scraps of these non-ferrous metals are introduced briefly here.

MOF-based Sensing Materials for Non-enzymatic Glucose Sensors

  • Jingjing Liu;Xiaoting Zha;Yajie Yang
    • Journal of Electrochemical Science and Technology
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    • v.15 no.1
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    • pp.32-50
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    • 2024
  • Diabetes mellitus is one of the common chronic diseases, seriously threating to human health. The continuous monitoring of blood glucose concentration can effectively prevent diabetic diseases. The sensing performance of glucose non-enzymatic sensors is mainly determined by working electrode materials. Metal-organic frameworks (MOFs) are recognized as promising candidate for glucose sensor application, due to its large surface areas, ordered porous structure and nearly infinite designability. In this review, the sensing performance, research progress and future challenge of non-enzymatic glucose sensors based on MOF-based materials in recent years are presented. We hope that this review would provide valuable technology guidance for high performance non-enzymatic glucose sensors based on MOFs.

Evaluation of the Effect of Metal Artifacts Varying the Parameters of the Attenuation Map for the artificial Hip Joint in SPECT/CT (SPECT/CT에서 인공고관절에 대한 감쇠보정지도(Attenuation Map)의 매개변수 변화에 따른 금속 인공물(Metal Artifact)의 영향 평가)

  • Kim, Sang Gyu;Kim, Jung Yul;Park, Min Soo;Jo, Seung Hyun;Lim, Han Sang;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.2
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    • pp.3-7
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    • 2014
  • Purpose SPECT/CT scan to be performed attenuation correction on the basis of CT induce an overestimation of the site due to the beam hardening artifact by metal cover and reduce the images quality. Therefore, this study using a phantom that has been inserted artificial hip joint investigated that effect on the SPECT/CT image causing by metal artifact for varying the parameters of the Attenuation Map. Materials and Methods Siemens Symbia T16 SPECT/CT equipment was used. Artificial hip joint was inserted to SPECT/PET phantom, 17 mm sphere of Bright Streak area in CT image was filled with Tc-99m so that the radiation activity was 8 times compared to background. And then Hot and Background was measured in varying Wide Beam Coefficient on Attenuation Map and RBR (Region to Background Ratio) of Metal and Non-Metal was calculated and analyzed depending on the presence or absence of the hip joint. Results It tended to hot count of Non-Metal and Metal to increase as the value of the manual mode is increased, hot count ratio with the group of both manual mode 0.5 and 0.4 is the best match. Also, in automatic mode, the ratio of RBRNon-Metal and RBRMetal was 1.135, statistically significant difference was not observed in the manual mode 0.5 and 0.4. Conclusion In the automatic mode of Wide Beam Coefficient in attenuation correction map, it was found that it is over-correction by 13.52%, it was possible to minimize the over-correction by the artifact in 0.5 and 0.4 of manual mode. Further studies should be performed in order to apply to a patient with the help of this and it is considered possible to reduce the over-correction by the metal artifact of an artificial hip joint for Hip-Resurfacing Arthroplasty patients, and to improve the diagnostic performance.

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Substrate Variety of a Non-metal Dependent Tagatose-6-phosphate Isomerase from Staphylococcus aureus (Staphylococcus aureus 유래 비금속성 이성화효소인 Tagatose-6-phosphate Isomerase의 기질다양성)

  • Oh Deok-Kun;Ji Eun-Soo;Kwon Young-Deok;Kim Hye-Jung;Kim Pil
    • Microbiology and Biotechnology Letters
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    • v.33 no.2
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    • pp.106-111
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    • 2005
  • To investigate the substrate variety of a putative non-metal dependent isomerase, the tagatose-6-phosphate isomerase (E.C. 5.3.1.26) structural genes (lacB; 510bp and lacA; 430bp) of Staphylococcus aureus were subcloned and co-expressed. Based on the substrate configuration, various aldoses were surveyed for substrate of ketose isomerization. Among the 10 aldoses tested, D-ribose and D-allose were isomerized by the enzyme. The subunit A and B showed more than $95\%$ activity for D-ribose and $75\%$ for D-allose in the presence of 1mM EDTA compared with non-EDTA conditions, which implying tagatose-6-phosphate isomerase is a non-metal dependent isomerase. Each of subunit A or subunit B alone showed no activity for any of the substrates tested. The affinity constant ($K_m$) of tagatose-6-phosphate isomerase against D-ribose and D-allose were 26 mM and 142 mM, respectively.