• 전자통신동향분석
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• 제38권5호
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• pp.90-99
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• 2023

Recently, with the trend of information technology convergence and electrification, batteries are being widely used in fields such as industry, transportation, and specific applications. By 2030, the secondary battery market is expected to grow explosively by more than eight times compared with 2020 to $351.7 billion owing to the expanding adoption of electric vehicles. Depending on the electrochemical reactions in the electrode, a primary battery can only discharge through an irreversible reaction, while a secondary battery can be repeatedly charged and discharged using reversible reactions. According to the type of charge carrier ions, secondary batteries may be classified into those made of lithium, sodium, potassium, magnesium, and aluminum ions. We analyze the current status and technological issues of lithium-ion batteries, lithium-sulfur batteries, and solid-state batteries, which are representative examples of lithium secondary batteries. In addition, research trends in lithium secondary batteries are discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.221-223
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• 2002

We have measured the secondary electron emission yield ${\gamma}_i$ from MgO films deposited on $SiO_2/Si$ for low energy noble ions. A pulsed ion beam technique was employed in order to suppress the surface charging effect during the measurement. From the measurement of the ion - induced secondary electron emission coefficients ${\gamma}_i$ for 5 noble ions with energies ranging from 50 eV to 225 eV, it was shown that, with increasing the kinetic energies of the incident ions, the ${\gamma}_i$ increased

• 천문학회보
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• 제43권1호
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• pp.51.3-52
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• 2018

Since Voyager 1 passed the Heliopause in 2012, it has provided the observations of the charged particles in the local interstellar medium. However, Voyager 1 only provides the information along with its trajectory. In order to understand the global view of the interstellar plasma flow surrounding the Heliopause, we need another tool. When the interstellar plasmas approach the Heliopause, the ions are deflected around the Heliopause due to the draping of the interstellar magnetic field. The draping of the interstellar magnetic field is strongly connected with the shape of the Heliopause. A fraction of the diverted ions exchanges their charges with the undisturbed primary interstellar neutral atoms, and then the ions become neutral atoms called the secondary interstellar neutral atoms. The newly created neutral atoms carry information on the diverted flow of the interstellar ions, and a fraction of them can travel to the Sun. Therefore, the secondary component of the interstellar neutrals is an excellent diagnostic tool to provide important information to constrain the shape of the Heliopause. The secondary interstellar neutrals are observed by Interstellar Boundary Explorer (IBEX) at Earth's orbit. Since 2009, two energetic neutral atom cameras on IBEX have measured neutral atoms and it has provided sky maps of neutral atoms. In this presentation, we will discuss the directional distribution of the secondary interstellar neutrals at Earth's orbit. In the sky maps, the primary interstellar neutral gas is seen between $200^{\circ}$ and $260^{\circ}$ in ecliptic longitude and the secondary components are seen in the longitude range of $160^{\circ}-200^{\circ}$. We also present a simplified model of the outer heliosheath to help interpret the observations of interstellar neutrals by the IBEX-Lo instruments. We extract information on the large-scale shape of the Heliopause by comparing the neutral flux measured at IBEX along four different look directions with simple models of deflected plasma flow around hypothetical obstacles of different aspect ratios to the flow. Our comparisons between the model results and the observations indicate that the Heliopause is very blunt in the vicinity of the Heliospheric nose, especially compared to a Rankine half-body or cometary shape.

• 대한화학회지
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• 제38권7호
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• pp.509-515
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• 1994

고리(12C4, 15C5, 18C6, DT18C6, DA18C6) 및 비고리$(Q_2O_5)$ 폴리에테르와 11가지의 1차 및 2차 알킬암모늄 이온과의 상호작용을 NMR 적정과 전기전도도법으로 조사하였다. 모든 알킬암모늄 이온은 크라운 에테르 및 비고리 폴리에테르와 수소결합에 의해 비교적 안정한 1:1 착물을 형성하였다. 알킬암모늄 이온과 동공의 크기가 다른 동일계열 호스트와의 상호작용의 세기는 18C6 > 15C5 > 12C4 순이었으며, 알킬암모늄 이온에 대한 호스트 주개원자의 세기는 N > O > S 순이었다. 18C6는 2차 알킬암모늄 이온에 비해 1차 알킬 암모늄 이온과 더 강한 상호작용을 하는 반면, DA18C6는 2차 알킬암모늄 이온과 더 강한 상호작용을 하였다. 또한 25$^{\circ}C$ 메탄올에서 18C6와 알킬암모늄 이온과의 착물형성에 대한 안정도 상수를 전기전도도법에 의해 구하였다. 착물의 안정도는 주로 알킬암모늄의 차수(또는 수소결합 수), 알킬기의 길이, 알킬기의 구조에 의한 입체장애 등에 의해 크게 영향을 받았다.

• 상하수도학회지
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• 제30권6호
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• pp.683-690
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• 2016

Modified coagulants were investigated for the removal of phosphorus from secondary effluent of wastewater treatment. The modified coagulants were prepared by mixing alkali earth metal ions such as calcium and magnesium. The basicity of a coagulant influenced on the removal of phosphorus, and coagulants with basicity of 5.9% showed a better removal of total phosphorus than that of 38.5%. Also, coagulants with alkali earth metals enhanced the performance of coagulation by 10% and resulted in 67.1% for total phosphorus removal. Moreover, the removal of suspended solids and chemical oxygen demand was improved using coagulants with low basicity and earth metal ions. Results of this study demonstrated that the use of coagulants with low basicity, and calcium and magnesium ions is recommended to improve wastewater effluent quality.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.105.1-105.1
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• 2016

Many of the complex materials developed today derive their unique properties from the presence of multiple phases or from local variations in elemental concentration. Simply performing analysis of the bulk materials is not sufficient to achieve a true understanding of their physical and chemical natures. Secondary ion mass spectrometer (SIMS) has met with a great deal of success in material characterization. The basis of SIMS is the use of a focused ion beam to erode sample atoms from the selected region. The atoms undergo a charge exchange with their local environment, resulting in their conversion to positive and negative secondary ions. The mass spectrometric analysis of these secondary ions is a robust method capable of identifying elemental distribution from hydrogen to uranium with detectability of the parts per million (ppm) or parts per billion (ppb) in atomic range. Nano secondary ion mass spectrometer (Nano SIMS, Cameca Nano-SIMS 50) equipped with the reactive ion such as a cesium gun and duoplasmatron gun has a spatial resolution of 50 nm which is much smaller than other SIMS. Therefore, Nano SIMS is a very valuable tool to map the spatial distribution of elements on the surface of various materials In this talk, the surface imaging applications of Nano SIMS in KBSI will be presented.

• 한국진공학회지
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• 제1권1호
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• pp.121-125
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• 1992

Secondary Ion Mass Spectrometry (SIMS) is widely known as highly sensitive a surface analysis technique. Efforts for quantification have been hindered, however, by the presence of matrix effects. Here we describe a new technique for the quantitative analysis of AlxGa1-xAs. Instead of Al+, Ga+, As+ ions, CsX+ ions (X=Al, Ga, As) have been detected. Intensity of these molecular ions appears to be much less affected by matrix effects. We have successfully accomplished the compositional analysis with standard deviation better than 2 percent.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.953-956
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• 2008

Using the theoretical model of Auger electron emission, effects of MgO properties which include band gap energy, escape probability, gas ion, and doping elements on the yield of secondary electron emission were examined. The results indicated that the band gap of MgO must be decreased and escape probability must be enhanced in order to increase the yield of secondary electrons from Xe ions and that may proved to be a critical for achieving high luminance efficacy in ac-PDPs.

• 세라미스트
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• 제22권4호
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• pp.357-367
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• 2019

Secondary Ion Mass Spectrometry(SIMS) is an analytical method that measures the distribution and concentration of elements or compounds by analyzing the mass of secondary ions released by irradiating ion beams with energy of hundreds eV to 20 keV on the sample surface. Unlike other similar analytical instruments, SIMS directly detect the elemental ions that constitute a sample, allowing you to accurately identify components and obtain concentration information in the depth direction. It is also a great feature for measuring isotopes and analyzing light elements, especially hydrogen. In particular, with the development of materials science, there is an increasing demand for trace concentration analysis and isotope measurements in the micro-regions of various materials. SIMS has a short history compared to other similar methods; nevertheless, SIMS is still advancing in hardware and is expected to contribute to the development of materials science through research and development of advanced analytical techniques.

• Bulletin of the Korean Chemical Society
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• 제21권11호
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• pp.1119-1124
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• 2000

$\beta-Cyclodextrin$ derivatives connected with diaza-18-crown-6 through flexible bridges (R) at the secondary face 1a-c (1a: R = $-(CH_2)4-;$ 1b: R = $-CH_2CH_2OCH_2CH2-;$ 1c: R = $-(CH_2)8-)$ have been prepared. The associa tion constants of 1 with (2-naphthoxy)alkylammonium ions (2a: alkyl = butyl; 2b: alkyl = octyl) were determined by induced circular dichroism (ICD) spectroscopy and it was found that the derivatization of $\beta-CD$ with the diazacrown resulted in enhanced binding with 2, compared to the native $\beta-CD.$ ICD Characteristics of the host-guest complexes indicate that a part of the alkylammonium moiety of 2 is protruded from the secondary side of the $\beta-CD$ cavity, and the guest molecules 2a and 2b move to the secondary and primary side, respectively, to make the binding of the ammonium group with the diaza-18-crown-6 moiety more feasible. The energy accompanied by the relocation of the guest molecules inside $\beta-CD$ moiety is compensated by the interaction energy between the ammonium ion and diazacrown ether.