• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.238-244
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• 2013

In energy dispersive X-ray fluorescence analysis, the removal of the continuum on which the X-ray spectrum is superimposed is one of the most important processes, since it has a strong influence on the analysis result. The existing methods which have been used for it usually require tight constraints or prior information on the continuum. In this paper, an efficient background correction method is proposed for Energy Dispersive X-ray fluorescence (EDXRF) spectra. The proposed method has two steps of background modeling and background correction. It is based on the basic concept which differentiates background areas from the peak areas in a spectrum and the SNIP algorithm, one of the popular methods for background removal, is used to enhance the performance. After detecting some points which belong to the background from a spectrum, its background is modeled by a curve fitting method based on them. And then the obtained background model is subtracted from the raw spectrum. The method has been shown to give better results than some of traditional methods, while working under relatively weak constraints or prior information.

• Fibers and Polymers
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• v.2 no.1
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• pp.135-139
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• 2001

Poly(hydroxamic acid) resin beads were prepared and complexed with various metal ions. We used IR spectroscopy to investigate the structure of metal complex. It proved that the products formed by introduction of metal ions gave stable and colored complex. It was found that the resin bead as synthesized would be a good column packing material for continuous extraction. Energy dispersive spectroscopy was use to study the distribution of metal ions in the resin matrix. It could be tentatively concluded that adsorption and diffusion of metal ions in the chelating resins mainly depended on the loading of the resin matrix which indicated interacting sites with metal ions.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.437-437
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• 2014

Various oxide particles are synthesized in an ambient condition using an electron beam irradiation system. The formation of oxide particles is confirmed by FT-IR spectra results and the X-ray photoelectron spectrum. It is also shown that the morphology and size of oxide particles are significantly influenced by the type and flowrate of dilution gas. The energy dispersive X-ray (EDX) analysis also confirms that various oxide particles are synthesized.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.110-113
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• 2012

ZnO crystals with a baseball bat shape were synthesized without any catalysts through a simple thermal oxidation of ZnS powder in alumina crucible under air atmosphere. SEM images demonstrated that the bat structure was composed of two pieces of ZnO crystals, i.e hexagonal-shaped rod and inverted cone-shaped rod. X-ray diffraction (XRD) pattern revealed that the ZnO crystals had wurtzite hexagonal structure. Energy dispersive X-ray (EDX) spectrum showed that the ZnO was of high purity. A strong green emission peak at 510 nm was observed in cathodoluminescece spectrum.

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.377-389
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• 2022

The current global energy supply depends heavily on fossil fuels. This makes technology such as direct water splitting from harvesting solar energy in photoelectrochemical (PEC) systems potentially attractive due to its a promising route for environmentally benign hydrogen production. In this study, undoped and nickel-doped molybdenum oxide photoanodes (called photoanodes S₁ and S₂ respectively) were synthesized through electrodeposition by applying -1.377 V vs Ag/AgCl (3 M KCl) for 3 hours on an FTO-coated glass substrate immersed in molibdatecitrate aqueous solutions at pH 9. Scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) were used for microstructural and compositional characterizations of the photoanodes. In addition, the optical and photoelectrochemical characterizations of these photoanodes were performed by UV-Visible spectroscopy, and linear scanning voltammetry (LSV) respectively. The results showed that all the photoanodes produced exhibit conductivity and catalytic properties that make them attractive for water splitting application in a photoelectrochemical cell. In this context, the photoanode S₂ exhibited better photocatalytic activity than the photoanode S₁. In addition, photoanode S₂ had the lowest optical band-gap energy value (2.58 eV), which would allow better utilization of the solar spectrum.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2771-2775
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• 2010

We present a rapid biogenic method for the production of nanoscale gold particles using pear extract. The formation and stability of pear-derived gold nanoparticles (Pear-AuNPs) were monitored by ultraviolet-visible spectroscopy. Their morphology, elemental composition and crystalline phase were determined by transmission electron microscopy, energy-dispersive X-ray spectroscopy and selected area electron diffraction. The average core size of crystalline Pear-AuNPs was in the range of $10{\pm}5\;nm$ and the observed morphology was spherical. The X-ray photoelectron spectrum showed a strong peak for the pure 'Au' phase. The circular dichroism spectrum indicated the natural capping ability of the pear extract, which generated peptide-gold nanoparticles. These nanoparticles were stable in aqueous solution for two months. A cell viability assay of Pear-AuNPs showed biocompatibility with human embryonic kidney 293 cells. Accordingly, this eco-friendly process for the bio-mimetic production of Pear-AuNPs is nontoxic in nature; consequently, it will find potential application in nano-biotechnology.

• Journal of Korea Water Resources Association
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• v.38 no.6 s.155
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• pp.429-438
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• 2005

In this study, a couple of ordinary differential equations which can describe random waves are derived from the Boussinesq equations. Incident random waves are generated by using the TMA(TEXEL storm, MARSEN, ARSLOE) shallow-water spectrum. The governing equations are integrated with the 4-th order Runge-Kutta method. By using newly derived wave equations, nonlinear energy interaction of propagating waves in constant depth is studied. The characteristics of random waves propagate over a sinusoidally varying topography lying on a sloping beach are also investigated numerically. Transmission and reflection of random waves are considerably affected by nonlinearity.

• Asian Journal of Atmospheric Environment
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• v.6 no.4
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• pp.275-280
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• 2012

To understand the effect of aerosols on the growth and physiological conditions of trees in forests, it is important to know the state of aerosols that are deposited on the surface of the leaves or needles. In this study, we developed methods of visualization of submicron-sized aerosols that were artificially deposited from the gas-phase or liquid phase onto tree leaves or needles in trees. Firstly, we used field-emission scanning electron microscopy (FE-SEM) to observe black carbon (BC) particles that were artificially sprayed onto the leaves or needles. The distribution of BC particles deposited on the leaves and needles were distinguished based on the size and morphological features of the particles. The distribution and agglomerates size of BC particles differed between two spraying methods of BC particles employed. Secondly, we tried to visualize gold (Au) particles that were artificially sprayed onto the leaves using energy dispersive X-ray spectrometry (EDX) coupled to FE-SEM. We detected the Au particles based on the characteristic X-ray spectrum, which was secondarily generated from the Au particles. In contrast to the case of BC particles, the Au particles did not form agglomerates and were uniformly distributed on the leaf surfaces. The present results show that our methods provide useful information of adsorption and/or behavior of fine particles at the submicron level on the surface of the leaves.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1630-1632
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• 1999

In this paper, we studied the short circuit current and molten mark of polyvinyl chloride insulated flexible cords(VFF). The calory decreased remarkably with increase of current. The surface structure and composition of a strand wire were analyzed by stereoscope, scanning electron microscope (SEM), and energy dispersive x-ray spectroscopy(EDX). The surface of a strand wire showed columnar and void. The intensity of CuL spectrum increased in melted mark.

• ETRI Journal
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• v.26 no.3
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• pp.252-256
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• 2004

We formed silver nanocrystallites by the thermal decomposition of a $Ag^{+1}$-oleate complex, which was prepared by a reaction with $AgNO_{3}$ and sodium oleate in a water solution. The resulting monodispersed silver nanocrystallites were produced by controlling the temperature (290$^{\circ}$C). Transmission electron microscopic (TEM) images of the particles showed a 2-dimensional assembly of the particles with a diameter of $9.5{\pm}0.7nm$, demonstrating the uniformity of these nanocrystallites. An energy-dispersive X-ray (EDX) spectrum and X-ray diffraction (XRD) peaks of the nanocrystallites showed the highly crystalline nature of the silver structure. We analyzed the decomposition of the $Ag^{+1}$-oleate complex using a Thermo Gravimetric Analyzer (TGA) and observed the crystallization process using XRD.