• Title/Summary/Keyword: secondary ions

Search Result 224, Processing Time 0.028 seconds

Technology Trends for Lithium Secondary Batteries (리튬 이차전지 기술 동향)

  • Y.H. Choi;H.S. Chung
    • Electronics and Telecommunications Trends
    • /
    • v.38 no.5
    • /
    • pp.90-99
    • /
    • 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.

Slow Noble Ion - Induced Secondary Electron Emission Characteristics of MgO Layer.

  • Lee, Sang-Kook;Kim, Jae-Hong;Lee, Ji-Hwa;Whang, Ki-Woong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.221-223
    • /
    • 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

  • PDF

The Flow of the Interstellar Plasmas surrounding the Heliopause estimated via IBEX-Lo Observations

  • Park, Jeewoo;Kucharek, Harald;Isenberg, Philip A.;Paschalidis, Nikolaos
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.43 no.1
    • /
    • pp.51.3-52
    • /
    • 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.

  • PDF

Host-Guest Interactions of Cyclic and Acyclic Polyethers with Alkylammonium Ions (고리 및 비고리 폴리에테르와 알킬암모늄 이온과의 호스트-게스트 상호작용)

  • Jeong, Jong Hwa;Kim, Dae Yeon;Lee, Sim Seong
    • Journal of the Korean Chemical Society
    • /
    • v.38 no.7
    • /
    • pp.509-515
    • /
    • 1994
  • The interactions of 11 kinds of primary and secondary alkylammonium ions with cyclic (12C4, 15C5, 18C6, DT18C6 and DA18C6) and acyclic$(Q_2O_5)$ polyethers were investigated by NMR titration and conductometry. All of the alkylammonium ions under investigation form the relatively stable 1 : 1 complexes with crown ethers and acyclic polyether by H-bond. The interactions of alkylammonium ions with analogeous hosts having different size were in the order of 18C6 > 15C5 > 12C4, and the strengthes of donor atoms toward the alkylammonium ions were in the order of N > O > S. 18C6 forms more favorable interactions with primary alkylammonium ions than secondary alkylammonium ions, otherwise DA18C6 shows the opposite behaviors. The stability constants for complexations of 18C6 with the alkylammonium ions were determined conductometrically in methanol at 25$^{\circ}C$. The major factors affecting the stability of complexes were the type of alkylammonium ions, the length of alkyl-chain and the steric hindrance due to the structure of alkyl groups on complexation.

  • PDF

Improved Coagulant for High Efficiency Phosphorus Removal in Secondary Effluent of Waste Water Treatment Plant (하수처리장 2차 처리수의 고효율 인 제거를 위한 응집제 개선)

  • Choi, Jeung-seung;Lee, Byung-ha;Kim, Ki-pal;Baek, Dae-jin
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.30 no.6
    • /
    • pp.683-690
    • /
    • 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.

A New Approach to Surface Imaging by Nano Secondary Ion Mass Spectrometry

  • Hong, Tae-Eun;Byeon, Mi-Rang;Jang, Yu-Jin;Kim, Jong-Pil;Jeong, Ui-Deok
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2016.02a
    • /
    • pp.105.1-105.1
    • /
    • 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.

  • PDF

The Detection of Molecular Ion $CsX^+$(X=Al, Ga, As) for Quantitative SIMS Analysis ($CsX^+$(X=Al, Ga, As) 분자이온을 이용한 SIMS의 정량분석)

  • 김차연;김선미;김성태;지종열
    • Journal of the Korean Vacuum Society
    • /
    • v.1 no.1
    • /
    • pp.121-125
    • /
    • 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.

  • PDF

A Parametric Study on Secondary Electron Emission from MgO

  • Yoon, Sang-Hoon;Kim, Yong-Seog
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.953-956
    • /
    • 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.

  • PDF

Secondary Ion Mass Spectrometry : Theory and Recent trends (이차이온질량분석기의 원리와 분석법 동향)

  • Byeon, Mirang;Kim, Da Young;Hong, Tae Eun
    • Ceramist
    • /
    • v.22 no.4
    • /
    • pp.357-367
    • /
    • 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.

Synthesis of Diaza-18-Crown-6-Functionalized b-Cyclodextrin Derivatives at the Secondary Side and Induced Circular Dichroism Studies of Their Complexes with (2-Naphthoxy)alkylammonium Ions

  • Park, Gwang Hui Go;Kim, Yeong Sim;Song, Hui Eun;Park, Jun U
    • Bulletin of the Korean Chemical Society
    • /
    • v.21 no.11
    • /
    • pp.1119-1124
    • /
    • 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.