• Title/Summary/Keyword: antimony

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A Study on the Effects of Flame Retardants in Unsaturated Isophthalic Acid Polyester Resin (불포화 이소프탈산 폴리에스터 수지의 난연제 첨가 효과 연구)

  • 최원종
    • Fire Science and Engineering
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    • v.12 no.4
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    • pp.41-49
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    • 1998
  • In this study, the thermal improvement of an isophthalic acid polyester resin by the incorporation of flame retardants has been investigated. Aluminium hydroxide, antimony oxide and alumina powder were used to formulate the flame retardant systems. The improvement of an isophthalic resin by incorporating aluminium hydroxide is dramatic(burning rate and smoke emission are reduced), although the mechanical property is decreased significantly. The addition of small amount(2.5 phr) of antimony oxide produces high char yield(31%) which acts as a protective layer on the surface of the resin.

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Orientation and Defects of $SnO_2$ Films Deposited by Spray Pyrolysis (무열분해법으로 증착한 $SnO_2$ 박막의 방향성과 결함구조)

  • Kim, Tae-Heui;Park, Kyung-Bong
    • Solar Energy
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    • v.18 no.2
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    • pp.137-144
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    • 1998
  • Tin oxide films deposited by spray pyrolysis have defects and preferred orientations according to the temperature of substrate. The growth of crystalline deposits began at the substrate temperature of $300^{\circ}C$. With increasing substrate temperature the plane (200) groved preferentially and above $400^{\circ}C$, planes of higher indices. Grain size increased with increasing substrate temperature up to $400^{\circ}C$. Undoped film is composed of Sn and O, and contains oxygen vacancies. Film doped with antimony has defects such as oxygen vacancies, antimony substituted on Sn and chlorine on oxygen.

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A Study on the Electrical and Optical Properties of SnO2:Sb Thin Films Prepared by Different Conditions for Photovoltaic Applications (태양전지용 SnO2:Sb 박막의 제조 조건에 따른 전기적, 광학적 특성 연구)

  • Lee, Jae-Hyeong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.3
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    • pp.269-276
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    • 2009
  • Antimony doped tin oxide ($SnO_2:Sb$) films, which are used as the front contact and back reflector of thin film solar cells, have been deposited by d,c, magnetron sputtering. The dependence of electrical and optical properties of the films on the preparation conditions, such as $O_2$ gas ratio, substrate temperature, annealing temperature was investigated. The sputter gas composition was found to affect the properties of the films. With incorporating $O_2$ gas, the electrical and optical properties of films significantly were improved. The minimum resistivity and optical transmittance over 80 % in visible region were obtained at the oxygen concentration of 30 %, When the substrate temperature was higher, the resistivity of $SnO_2:Sb$ films was decreased, while the absorption edge shifted to shorter wavelength, indicating higher optical band gap. Heat treatment over $600^{\circ}C$ resulted in poorer electrical and optical properties due to SnO phase (102) plane.

The Effects of Additions of In & Sb on Resistivity & Sensitivity in Tin Oxide Gas Sensors (In과 Sb의 첨가가 Tin Oxide 가스센서에서 Resistivity와 Sensitivity에 미치는 영향)

  • Son, Y.M.;Han, S.D.;Kim, J.W.;Sim, K.S.
    • Journal of Sensor Science and Technology
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    • v.1 no.2
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    • pp.165-172
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    • 1992
  • To determine the effect of additions of trivalent and pentavalent ions on the electrical conductivity and sensing behaviour, indium and antimony were incorporated in tin oxide by the coprecipitation method. Antimony may be considered to enter the cassiterite structure as pentavalent ions, thermal energy could excite electrons from these ions into the conduction band. Similarly the indium ions would enter the lattice as $In^{3+}$ but could accept electrons from the valence band, thereby becoming monovalent or divalent. These phenomena, however, how the potential barrier existing $SnO_{2}$ by addition of two kinds of ions could influence on the sensing behaviour in comparison with their influence on the resistivity were observed.

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The Effect of ATH and Sb$_2$O$_3$on the Flammability and Mechanical Properties of Fiber Reinforced Plastics (ATH, Sb$_2$O$_3$조성에 따른 복합재료의 난연특성)

  • 강길호;최원종;김진곤;권경옥;박상윤;사공성호;김해형
    • Fire Science and Engineering
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    • v.16 no.4
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    • pp.65-71
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    • 2002
  • In this paper, the thermal and flame properties of GFRP with various flame retardant(aluminum trihydrate, antimony trioxide) compositions have been investigated by thermal analysis and flammability tests(LOI test, flammability 45 degree test). The flame and mechanical properties(hardness, tensile strength, modulus) of general purpose grade glass fiber/unsaturated polyester composite with flame retardant composition have been also evaluated. The effect of cure pressure on the flame properties of aerospace grade glass fiber/epoxy composite was investigated. Considering the flame and mechanical property of composite, we could determine the optimum flame retardant composition(ATH 10∼20 phr). Test results show that the flame property of glass fiber/epoxy composite is considerably affected by cure pressure conditions.

A Study of Experiment and Developed Model by Antimony High Energy Implantation in Silicon (실리콘에 고에너지 안티몬이온주입의 실험과 개선된 모델에 관한 연구)

  • Jung, Won-Chae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.11
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    • pp.1156-1166
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    • 2004
  • Antimony profiles by MeV implantation are measured by secondary ion mass spectrometry (SIMS) and spreading resistance (SR). The moments of SIMS and simulated profiles are calculated and compared for the exact range in MeV energy. SRIM, DUPEX, ICECREM, and TSUPREM4 simulation programs are used for the calculation of range 1D, 2D. SRIM is a Monte Carlo simulation program and different inter-atomic potentials can be used for the calculation of nuclear stopping power cross-section (Sn) and range moments. Nevertheless, the range parameters were not influenced from nuclear stopping power in MeV. Through the modification of electronic stopping power cross-section (Se), the results of simulation are remarkably improved and matched very well with SIMS data. The values of electronic stopping power are optimized for Sb high energy implantation. For the electrical activation, Sb implanted samples are annealed under $N_2$ and $O_2$ ambient. Finally, Oxidation retard diffusion(ORD) effect of Sb implanted sample are demonstrated by SR measurements and ICECREM simulation.

Experimental Investigation on Friction Performance of Brake Linings with Two Different Solid Lubricants (두 종의 고체윤활제에 따른 마찰재의 마찰성능에 관한 실험적 고찰)

  • Kim, Seong-Jin;Bae, Eun-Gap;Yoon, Ho-Gyu;Jang, Ho
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.06a
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    • pp.72-78
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    • 2001
  • An experimental investigation was conducted to examine the tribological behavior of NAO (non-asbestos organic) type brake linings containing different volume ratios of graphite and antimony trisulfide (Sb$_2$S$_3$). In order to investigate the effect of the solid lubricants on brake performance, three different friction tests (pressure, speed, and temperature sensitive tests) were carried out using a scale dynamometer. The test results showed that the friction characteristics were strongly affected by the type and the amount of solid lubricants in the brake lining. It was found that the brake linings with both solid lubricants were better in friction stability due to the complementary role of the two disparate lubricating properties at various pressure and speed conditions. In particular, the brake lining containing higher concentrations of graphite showed better fade resistance than others during high temperature friction test.

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Leachability of lead, cadmium, and antimony in cement solidified waste in a silo-type radioactive waste disposal facility environment

  • Yulim Lee;Hyeongjin Byeon;Jaeyeong Park
    • Nuclear Engineering and Technology
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    • v.55 no.8
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    • pp.2889-2896
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    • 2023
  • The waste acceptance criteria for heavy metals in mixed waste should be developed by reflecting the leaching behaviors that could highly depend on the repository design and environment surrounding the waste. The current standards widely used to evaluate the leaching characteristics of heavy metals would not be appropriate for the silo-type repository since they are developed for landfills, which are more common than a silo-type repository. This research aimed to explore the leaching behaviors of cementitious waste with Pb, Cd, and Sb metallic and oxide powders in an environment simulating a silo-type radioactive waste repository. The Toxicity Characteristic Leaching Procedure (TCLP) and the ANS 16.1 standard were employed with standard and two modified solutions: concrete-saturated deionized and underground water. The compositions and elemental distribution of leachates and specimens were analyzed using an inductively coupled plasma optical emission spectrometer (ICP-OES) and energy-dispersive X-ray spectroscopy combined with scanning electron microscopy (SEM-EDS). Lead and antimony demonstrated high leaching levels in the modified leaching solutions, while cadmium exhibited minimal leaching behavior and remained mainly within the cement matrix. The results emphasize the significance of understanding heavy metals' leaching behavior in the repository's geochemical environment, which could accelerate or mitigate the reaction.

Comparison of the Results for Sentinel Lymph Node Mapping in the Breast Cancer Patients using $^{99m}Tc$-Antimony Trisulfide Colloid, $^{99m}Tc$-Tin Colloid, and $^{99m}Tc$-Human Serum Albumin (유방암 환자에서 $^{99m}Tc$-Antimony Trisulfide Colloid, $^{99m}Tc$-Tin Colloid, $^{99m}Tc$-Human Serum Albumin을 이용한 감시림프절 매핑 성적의 비교)

  • Jang, Sung-June;Moon, Seung-Hwan;Kim, Seok-Ki;Kim, Bom-Sahn;Kim, Seok-Won;Chung, Ki-Wook;Kang, Keon-Wook;Lee, Eun-Sook
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.6
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    • pp.546-552
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    • 2007
  • Purpose: In the breast cancer patient, lymphatic mapping and sentinel lymph node biopsy are the most important procedure for axillary lymph node staging. We aimed to compare the three radiocolloids [$^{99m}Tc$-antimony trisulfide colloid (ASC), $^{99m}Tc$-tin colloid (TC), and $^{99m}Tc$-human serum albumin (HSA)] for sentinel lymph node mapping. Subjects and Methods: Totally, 397 patients with clinically N0 stage were enrolled. $^{99m}Tc$-ASC was injected in 202 out of 397 patients, $^{99m}Tc$-TC was injected in 120 patients, and $^{99m}Tc$-HSA was injected in the remaining 75 patients. The sentinel lymph nodes were localized by lymphoscintigraphy and selected using intraoperative gamma probe. All sentinel lymph nodes were investigated by intraoperative pathologic consultation. The axillary lymph nodes which were harvested by the lymph node dissection were also investigated. Results: The patients of each group showed similar clinical characteristics. There were no significant differences (p>0.05) in the identification rate of sentinel lymph nodes (IR), false negative rate (FNR), and negative predictive value (NPV). The axillary lymphadenectomy revealed axillary lymph node metastases in those three groups (ASC-33.2%, TC-31.7%, HSA-22.7%). The IR, FNR, and NPV were not significantly different among those groups. Conclusion: Those three $^{99m}Tc$-labeled radiocolloids showed equivalent results in sentinel lymph node mapping of breast cancer.

Effects of antimony addition on growth of InGaN nano-structures by mixed-source HVPE (혼합소스 HVPE 방법에 의한 InGaN 나노구조의 성장에 있어서 Sb 첨가의 영향)

  • Ok, Jin-Eun;Jo, Dong-Wan;Jeon, Hun-Soo;Lee, Ah-Reum;Lee, Gang-Suok;Cho, Young-Ji;Kim, Kyung-Hwa;Chang, Ji-Ho;Ahn, Hyung-Soo;Yang, Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.20 no.3
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    • pp.113-116
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    • 2010
  • We report on the growth and characteristics of the structural and optical properties of InGaN nano-structures doped with antimony (Sb) as a catalyst. The use of catalyst has been explored to modify the growth and defect generation during strained layer heteroepitaxial growth. We performed the growth of the InGaN nano-structures on c-sapphire substrates using mixed-source hydride vapor phase epitaxy (HVPE). The characteristic of samples was measured by scanning electron microscope (SEM) and photoluminescence (PL). The aligning direction of c-axis of the InGaN nano-structures was changed from vertical to parallel or inclined to the surface of substrates when the Sb was added as a catalyst. The indium composition was estimated about 3.2% in both cases of with or without the addition of Sb in the InxGal-xN structures. From the results of InGaN nano-structures formed with the addition of Sb, we can expect the performance of optical devices would be more improved by reduced piezo-electric field if we use the InGaN nano-structures of which c-axes are aligned parallel to the substrates as an active layer.