• Analytical Science and Technology
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• v.24 no.3
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• pp.159-167
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• 2011

In this study, the hydride vapour generator inductively coupled plasma mass spectrometry (HVGICPMS) was applied as the new analytical method to show the high accurate and reproductive data analysing the amounts of selenium and germanium being existed inside a system of plant. In order to decrease the interference effects, such as ion and molecular interference. Mini torch was used into the ICPMS instead of the conventional torch. At conditions of the different kinds and concentrations of acid solution, the different reductive conditions for composing hydride, and the different methods for making ash, the contents of selenium and germanium in lettuce were analysed. The inspection of yields and data comparison from SRM-1574 and -1570a were used for increasing the accuracy of this analysis.

• Analytical Science and Technology
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• v.15 no.5
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• pp.439-444
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• 2002

DE-O-V ICP-AES has been studied for the analytical characteristics of As, Se, and Ge with PN, USN and HG. Effect of $NaBH_4$ and HCl on the signal intensity of As, Se and Ge with HG and E-O-V ICP-AES were closely investigated. The sensitivities of As, Se and Ge with HG were much greater than those with PN and USN. Accordingly, the detection limits of the elements with HG were lower by a factor of 100 and 10 than PN and USN, respectively.

• Nuclear Engineering and Technology
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• v.56 no.8
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• pp.3084-3089
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• 2024

An electron beam may be used to generate bremsstrahlung photons that go on to create photoneutrons within metals. This serves as a low-energy neutron source for irradiation experiments. In this article, we present simulation results for optimizing photoneutron yield for a 10-MeV electron beam on tantalum foil and erbium deuteride (ErD₃). The thickness of the metal layers was varied. A tantalum foil thickness of 1.5 mm resulted in the most photons reaching the second metal layer. When a second metal layer of ErD₃ was included, the photoneutron yield increased with the thickness of the secondary layer. When the electron beam was directly incident upon a layer of ErD₃, the photoneutron yield did not differ significantly from the yield when a layer of tantalum was included. The directional photoneutron yield reached a maximum level when the thickness of the ErD₃ layer was around 12 cm. About 1 neutron was generated per 10⁴ source electrons. When using a 2-mA beam current, it is possible to generate up to 10¹² neutrons per second, making this combination a relatively-inexpensive neutron generator.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.558-559
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• 2008

본 논문은 미 일리노이 주립대 어바나-샴페인 캠퍼스에서 주로 군사용 응용 관련하여 개발 중인 마이크로 PEM 연료전지 시스템 개발에 대한 논문이다. 본 연구는 수소 저장 장치까지 포함하여 1 $mm^3$의 초소형 연료전지 시스템을 목표로 진행 중이며 본 논문은 이러한 진행 과정 중 화학적 하이드라이드 기반의 수소 발생기와 10 $mm^3$의 시스템 개발 과정에 대해 보고한다.

• Economic and Environmental Geology
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• v.29 no.1
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• pp.21-24
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• 1996

Inductively coupled plasma atomic emission spectrophotometer (ICP/AES) is a versatile modern instruments for the multi-element analysis, but quantitative analysis using ICP/AES with normal pneumatic nebulizer is not applicable for the measurement of elemental concentrations in water down to the drinkining water standard level except a few elements because of poor detection limits. However, the detection limit can be lowered enough to measure drinking water standard, if ultrasonic nebulizer and/or hydride vapor generator is attached. This method is tested with groundwater samples from Tajeon area. It is confirmed that the elemental concentrations in these samples are within the limit of drinking water standard for the most elements. However, uranium concentration is very high in some samples compared with the concentrations suggested by Environmental Protection Agency of U.S.A. There is no standard concentration level to this element in Korea and it should be prepared immediately.

• Analytical Science and Technology
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• v.14 no.5
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• pp.416-421
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• 2001

The optimization of the reductant and acid concentration for stannane($SnH_4$) generation was investigated by using a continuous flow hydride generator combined with an inductively coupled plasma-atomic emission spectrometer. Several different prereductants were studied to remove the interfering effect of fluoride ion on the hydride generating of tin. The optimum acid concentration was 0.5-1.0 M for the 1-2% $NaBH_4$ and 1.0 M NaOH and the interfering effect of fluoride ion was minimized using boric acid and L-cysteine mixed solution as a prereductant. The reconveries of tin at 20 ng/mL level in the solution containing fluoride ion were 100~108 %.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.87-90
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• 2003

This research examines the feasibility of using laboratory-synthesized nano scale zero-valent iron particles to remove arsenic from aqueous phase. Batch experiments were performed to determine arsenic sorption rates as a function of the nano scale zero-valent iron solution concentration. Rapid adsorption of arsenic was achieved with the nano scale zero-valent iron. Typically 1 mg $L^{-1}$ arsenic (III) was adsorbed by 5 g $L^{-1}$ nano scale zero-valent iron below the 0.01 g $L^{-1}$ concentration within 7min. The kinetics of the arsenic sorption followed pseudo-first-order reaction kinetics. Observed reaction rate constants ( $K_{obs}$) varied between 11.4 to 129.0 $h^{-1}$ with respect to different concentrations of nano scale zero-valent iron. A variety of analytical techniques were used to study the reaction products including HGAAS (hydride generator atomic adsorption spectrophotometer), SEM (scanning electron microscopy) and TEM (transmission electron microscopy). Our experimental results suggest novel method for efficient removal of arsenic Iron groundwater.r.