• 제목/요약/키워드: LI14

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Cathodic Properties of $LiCoO_2$ Synthesized by a Sol-Gel Method for Lithium Ion Battery

  • 조봉준;정의덕;심윤보
    • Bulletin of the Korean Chemical Society
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    • 제19권1호
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    • pp.39-44
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    • 1998
  • $LiCoO_2$ powder was synthesized in an aqueous solution by a sol-gel method and used as a cathode active material for a lithium ion rechargeable battery. The layered $LiCoO_2$ powders were prepared by igniting in air for 12 hrs at 600 ℃ $(600-LiCoO_2)$ and 850 ℃ $(850-LiCoO_2)$. The structure of the $LiCoO_2$ powder was assigned to the space group R bar 3 m (lattice parameters a=2.814 Å and c=14.04Å). The SEM pictures of $600-LiCoO_2$ revealed homogeneous and fine particles of about 1 μm in diameter. Cyclic voltammograms (CVs) of $600-LiCoO_2$ electrode displayed a set of redox peaks at 3.80/4.05 V due to the intercalation/deintercalation of the lithium ions into/out of the $LiCoO_2$ structure. CVs for the $850-LiCoO_2$ electrode had a major set of redox peaks at 3.88/4.13 V, and two small set of redox peaks at 4.18/4.42 V and 4.05/4.25 V due to phase transitions. The initial charge-discharge capacity was 156-132 mAh/g for the $600-LiCoO_2$ electrode and 158-131 mAh/g for the $850-LiCoO_2$ electrode at the current density of 0.2 mA/cm2. The cycleability of the cell consisting of the $600-LiCoO_2$ electrode was better than that of the $850-LiCoO_2$. The diffusion coefficient of the $Li^+$ ion in the $600-LiCoO_2$ electrode was calculated as $4.6{\times}10^{-8}\; cm^2/sec$.

LiDAR 자료를 이용한 홍수 시뮬레이션에 관한 연구 (The Study of Flood Simulations using LiDAR Data)

  • 심정민;이석배
    • 대한공간정보학회지
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    • 제14권4호통권38호
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    • pp.53-60
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    • 2006
  • 본 연구는 LiDAR 측량 데이터를 이용하여 홍수피해 지역을 예측하고자 한 것으로, 이를 위해 고정밀 DEM 데이터를 이용하여 홍수범람도를 제작하였다. 울산시 태화강유역을 연구대상 지역으로 선정하여 LiDAR 데이터와 수치지도를 이용하여 각각 DEM을 작성하였고, 홍수량과 홍수위 결정에 있어서는 HEC 모델 프로그램과 MIKE 프로그램을 이용하여 홍수 시뮬레이션을 실시하였다. 축척1/5000 수치지도를 이용하여 제작한 DEM과 LiDAR 데이터를 이용한 DEM을 이용하여 동일조건에서 홍수 시뮬레이션을 적용한 결과 상당한 차이가 발생함에 따라 홍수 시뮬레이션은 고정밀 DEM 데이터로 작성된 데이터를 적용하는 것이 바람직하다는 것을 확인할 수 있었다. 홍수지도를 작성하기 위해서는 표고정밀도가 매우 중요한 요소이나, LiDAR 데이터를 이용하기 위하여 모든 지역의 하천지역에 대하여 LiDAR측량을 하는 것은 비경제적이므로 홍수 시뮬레이션이 필요한 중요한 시가화 지역에 대하여 우선적으로 LiDAR 데이터를 적용하여 제작하는 것이 필요하다. 홍수시뮬레이션의 기대효과로는 강우량에 따른 홍수피해지역을 사전에 예측하여 대책을 수립함으로써 재해예방 및 복구예산 절감 등의 효과가 있을 것으로 판단된다.

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$LiMn_{2-y}M_{y}O_4$ 정극 활물질의 전기화학적 특성 - I. $LiMn_{2-y}Mg_{y}O_4$의 결정 구조 및 AC Impedance 특성 (The Electrochemical Characterization of $LiMn_{2-y}M_{y}O_4$ Cathode Material - I. Crystal Structure and AC Impedance Properties of $LiMn_{2-y}Mg_{y}O_4$)

  • 정인성;김종욱;구할본;김형곤;손명모
    • 한국전기전자재료학회논문지
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    • 제14권4호
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    • pp.309-315
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    • 2001
  • Crystallized $LiMn_{2-y}Mg_{y}O_4$ powder was prepared by calcing the mixture of LiOH.$H_2O$, $MnO_2$ and MgO at $800^{\circ}C$ for 36h in an air atmosphere. The structure of $LiMn_{2-y}Mg_{y}O_4$ crystallites was analyzed from powder X-ray diffraction data as a cubic spinel, space group Fd3m. Though all cathode material showed spinel phase based on cubic phase in X-ray diffraction, other peaks gradually exhibited and became intense with increasing y value in $LiMn_{2-y}Mg_{y}O_4$. However, ununiform which calculated by (111) face and (222) face was constant in spite of the increase of y value, except pure $LiMn_2O_4$. AC impedance of Li/$LiMn_{2-y}Mg_{y}O_4$ cells revealed the similar resistance of about $70\Omega$ before cycling. In addition, The impedance of Li/$LiMn_{1.9}Mg_{0.1}O_4$ cell changed during charge and discharge or after cycling.

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UV-cured Polymer Solid Electrolyte Reinforced using a Ceramic-Polymer Composite Layer for Stable Solid-State Li Metal Batteries

  • Hye Min Choi;Su Jin Jun;Jinhong Lee;Myung-Hyun Ryu;Hyeyoung Shin;Kyu-Nam Jung
    • Journal of Electrochemical Science and Technology
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    • 제14권1호
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    • pp.85-95
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    • 2023
  • In recent years, solid-state Li metal batteries (SSLBs) have attracted significant attention as the next-generation batteries with high energy and power densities. However, uncontrolled dendrite growth and the resulting pulverization of Li during repeated plating/stripping processes must be addressed for practical applications. Herein, we report a plastic-crystal-based polymer/ceramic composite solid electrolyte (PCCE) to resolve these issues. To fabricate the one-side ceramic-incorporated PCCE (CI-PCCE) film, a mixed precursor solution comprising plastic-crystal-based polymer (succinonitrile, SN) with garnet-structured ceramic (Li7La3Zr2O12, LLZO) particles was infused into a thin cellulose membrane, which was used as a mechanical framework, and subsequently solidified by using UV-irradiation. The CI-PCCE exhibited good flexibility and a high room-temperature ionic conductivity of over 10-3 S cm-1. The Li symmetric cell assembled with CI-PCCE provided enhanced durability against Li dendrite penetration through the solid electrolyte (SE) layer than those with LLZO-free PCCEs and exhibited long-term cycling stability (over 200 h) for Li plating/stripping. The enhanced Li+ transference number and lower interfacial resistance of CI-PCCE indicate that the ceramic-polymer composite layer in contact with the Li anode enabled the uniform distribution of Li+ flux at the interface between the Li metal and CI-PCCE, thereby promoting uniform Li plating/stripping. Consequently, the Li//LiFePO4 (LFP) full cell constructed with CI-PCCE demonstrated superior rate capability (~120 mAh g-1 at 2 C) and stable cycle performance (80% after 100 cycles) than those with ceramic-free PCCE.

Thalidomide Combined with Chemotherapy in Treating Patients with Advanced lung Cancer

  • Li, Li;Huang, Xin-En
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권5호
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    • pp.2583-2585
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    • 2016
  • Objectives: To evaluate efficacy and toxicity in patients with advanced lung cancer, including non-small cell and small cell variants (NSCLC and SCLC), treated with thalidomide plus chemotherapy. Methods: Fourteen patients with advanced lung cancer were scheduled to receive chemotherapy combined with thalidomide. All patients in this study received thalidomide (100 mg orally per night before sleeping, produced by Changzhou Pharmaceutical Factory Co.Ltd) after the start of chemotherapy for at least 14 days. Chemotherapy was administered according to the condition of patients. After at least 14 days of treatment, efficacy and toxicity were evaluated. Results: There were 6 female and 8 male patients with advanced lung cancer recruited into this study, including 2 with SCLC and 12 with NSCLC. The median age was 56.7 (44-65) years. Progressive disease was observed in 12 patients (12/14), and stable disease in 2 (2/14). Grade 1 to 2 myelosuppression was observed in 4/14 patients, and Grade 1 to 2 elevation of hepatic enzymes was recorded in 5/14 patients. Adverse effects on the gastrointestinal tract were documented in 2/14 patients, all beingGrade 1. No Grade 3-4 toxicity was recorded. No treatment related deaths occurred. Conclusions: Our results demonstrate that thalidomide combined with chemotherapy is mildly effective and safe for treating patients with advanced lung cancer. However, further evaluation of this combination is warranted.

Strain Analysis for Quality Factor oft he Layered Mg0.93Ca0.07TiO3-(Ca0.3Li0.14Sm0.42)TiO3 Ceramics at Microwave Frequencies

  • Cho, Joon-Yeob;Yoon, Ki-Hyun;Kim, Eung-Soo
    • 한국세라믹학회지
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    • 제39권3호
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    • pp.222-225
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    • 2002
  • Microwave dielectric properties of the layered and functionally graded materials (FGMs) of $Mg_{0.93}Ca_{0.07}TiO_3$ (MCT) and $(Ca_{0.3}Li_{0.14}Sm_{0.42})TiO_3$(CLST) were investigated as a function of the volume ratio of two components. Dielectric constant was decreased with an increase of the volume ratio of MCT which had a lower dielectric constant thant CLST. For the layered FGMs specimens, the difference of thermal expansion coefficients between two components induced thermal strain to dielectric layers, which was confirmed by the plot of ${\Delta}$k (X-ray diffraction peak width0 versus k (scattering vector) using the double-peak Lorentzian function, f(x). Quality factor of the specimens was affected by the thermal strain of dielectric layer, especially MCT layer. For the specimen with the volume ratio of MCT/CLST = 2, the qulaity factor of the specimen showed a minimum value due to the maximum thermal strain fo MCT layer.

항공 라이다 자료를 이용한 토석류 발생지역의 지형복원기법 개발 (Development of the Topography Restoration Method for Debris Flow Area Using Airborne LiDAR Data)

  • 우충식;윤호중;이창우;이규성
    • 한국지리정보학회지
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    • 제14권3호
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    • pp.174-187
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    • 2011
  • 항공 LiDAR 측량으로 토석류 발생 전 후의 지형자료를 취득하는 경우 토석류로 인하여 유출된 토사량을 알 수 있다. 그러나 토석류 발생지를 미리 예측하여 촬영하기가 힘들고, 토석류 발생 지역의 과거 항공 LiDAR 자료는 존재가능성이 낮아 토석류 발생이전 지형자료를 이용하는 것은 어렵다. 따라서 본 연구에서는 토석류 발생지역의 토사량 추정을 위해 발생전 지형을 복원하고, 토사유출의 공간적 범위를 파악할 수 있는 지형복원기법을 개발하였다. 지형복원기법은 토석류 발생지역에서 추출한 선형 및 비선형 횡단면을 가우시안혼합모델로 수식화하고 중심점 추정방법과 근사정확도로 근사결과를 평가하여 토석류 발생이전의 지형을 복원한다. 지형복원기법은 토석류 발생 전 후의 항공 LiDAR 자료를 이용하여 두 가지 방법으로 검증하였다. 먼저 토석류 발생구간에서 추출한 각 횡단면을 지형복원하여 발생전 항공 LiDAR 자료와 비교하였다. 또한 토석류 발생지역에 지형복원기법을 적용한 뒤 지형자료를 제작하여 토석류 발생전 항공 LiDAR DEM과 비교하여 검증하였다. 지형복원기법의 검증한 결과 전반적으로 근사정확도가 0.5m에 가까운 높은 정확도를 나타냈다.

견우(LI15), 견료(TE14), 거골(LI16), 노수(SI10)에 시행한 인대 약침으로 치료된 견통 환자 4례 (Four Cases of Shoulder Pain Treated by Ligamentum Pharmacopuncture on Kyonu(LI15), Gyeollyo(TE14), Geogol(LI16) and Nosu(SI10))

  • 정상준;장여진;곽민경;김신애;위통순
    • Korean Journal of Acupuncture
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    • 제34권4호
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    • pp.271-276
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    • 2017
  • Objectives : The purpose of this study is to report 4 cases of shoulder pain treated by Ligamentum Pharmacopuncture. Methods : This study on shoulder pain was carried out on 4 patients who were treated at Department of Acupuncture & Moxibusition, Dongshin University, Korean Medicine Hospital from May 2016 to July 2016. All patients were treated 2~3 times based on the patient's condition. To evaluate change of pain and function, we used Shoulder Pain and Disability Index(SPADI), Numeric Rating Scale(NRS) and Range Of Motion(ROM). Evaluations were made at baseline and one week and two weeks after treatment. Results : There was remarkable improvement in SPADI, NRS and ROM. Conclusions : This study suggested the possibility that the ligamentum pharmacopuncture therapy may be useful for the treatment of shoulder pain. Follow-up study is needed.