• Title/Summary/Keyword: Product certification

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Synthesis and Structural Study of Extraframework ZrI6Tl119+ Cationic Cluster in Zeolite A (제올라이트 A 동공 내 비골격 ZrI6Tl119+ 양이온 클러스터의 합성과 구조 연구)

  • Hyeon Seung, Lim;Jong Sam, Park;Cheol Woong, Kim;Woo Taik, Lim
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.4
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    • pp.447-455
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    • 2022
  • Fully dehydrated Tl12-LTA (|Tl12|[Si12Al12O48]-LTA,Tl12-A) was treated with 6.0×103 Pa of ZrI4 (g) at 623 K for 72 hr under anhydrous conditions. The crystal structure of product, |Zr0.25I1.5Tl12|[Si12Al12O48]-LTA, was determined by single-crystal crystallography using synchrotron X-radiation in the cubic space group Pm3m (a = 12.337(2) Å). It was refined using all data to the final error index (for the 712 unique reflections for which Fo> 4σ(Fo) R1/wR2= 0.055/0.189. In this structure, octahedral ZrI62- ions center about 25% of the large cavities (Zr-I = 2.91(4) Å). Each coordinates to eight Tl+ ions and they are further bridged by Tl+ ions in the planes of 8-rings to form a cubic three-dimensional ZrI6Tl119+ cationic cluster. About 1.5 Tl+ ions per unit cell moved to deeper side of sodalite cavity after reaction with ZrI4(g). The remaining Tl+ ions occupy well-established cation positions near 6- and 8-rings.

Development of control system for complex microbial incubator (복합 미생물 배양기의 제어시스템 개발)

  • Hong-Jik Kim;Won-Bog Lee;Seung-Ho Lee
    • Journal of IKEEE
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    • v.27 no.1
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    • pp.122-126
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    • 2023
  • In this paper, a control system for a complex microbial incubator was proposed. The proposed control system consists of a control unit, a communication unit, a power supply unit, and a control system of the complex microbial incubator. The controller of the complex microbial incubator is designed and manufactured to convert analog signals and digital signals, and control signals of sensors such as displays using LCD panels, water level sensors, temperature sensors, and pH concentration sensors. The water level sensor used is designed and manufactured to enable accurate water level measurement by using the IR laser method with excellent linearity in order to solve the problem that existing water level sensors are difficult to measure due to foreign substances such as bubbles. The temperature sensor is designed and used so that it has high accuracy and no cumulative resistance error by measuring using the thermal resistance principle. The communication unit consists of two LAN ports and one RS-232 port, and is designed and manufactured to transmit signals such as LCD panel, PCT panel, and load cell controller used in the complex microbial incubator to the control unit. The power supply unit is designed and manufactured to supply power by configuring it with three voltage supply terminals such as 24V, 12V and 5V so that the control unit and communication unit can operate smoothly. The control system of the complex microbial incubator uses PLC to control sensor values such as pH concentration sensor, temperature sensor, and water level sensor, and the operation of circulation pump, circulation valve, rotary pump, and inverter load cell used for cultivation. In order to evaluate the performance of the control system of the proposed complex microbial incubator, the result of the experiment conducted by the accredited certification body showed that the range of water level measurement sensitivity was -0.41mm~1.59mm, and the range of change in water temperature was ±0.41℃, which is currently commercially available. It was confirmed that the product operates with better performance than the performance of the products. Therefore, the effectiveness of the control system of the complex microbial incubator proposed in this paper was demonstrated.