Structure and Performances of xLiFePO4/C·(1 − x)Li3V2(PO4)3/C Cathode for Lithium-Ion Batteries by Using Poly(vinyl alcohol) as Carbon Source

Chang-ling Fan,Wei-hua Zhang,Tao-tao Zeng,Ling-fang Li,Xiang Zhang,Shao-chang Han 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.11

Poly(vinyl alcohol), whose pyrolysis carbon possesses high conductivity of 8.88 × 10−1 S/cm, was used to synthesize xLiFePO4/C·(1 − x)Li3V2(PO4)3/C cathode. It was characterized by X-ray diffraction, scanning electron microscopy, conductivity, cyclic voltammetry, and galvanostatic charge and discharge experiments. Results show that LiFePO4/C and Li3V2(PO4)3/C coexists in the cathode. The particles sizes of 0.75LiFePO4/C·0.25Li3V2(PO4)3/C (x = 0.75) are much smaller than 100 nm due to the role of poly(vinyl alcohol). Its conductivity is 8.79 × 10−2 S/cm. The oxidative and reductive peaks in cyclic voltammetry are sharp and symmetrical. Their low potential gaps indicate that the extractions and insertions of lithium ion possess excellent reversibility. Its discharge capacities at 1 and 5 C are 141.1 and 100.1 mAh/g. The more Li3V2(PO4)3/C in cathode results in the deterioration of electrochemical performances due to its low theoretical capacity. It is concluded that poly(vinyl alcohol) is an effective carbon source in the preparation of xLiFePO4/C·(1 − x)Li3V2(PO4)3/C composite cathode with excellent performances.

Controllable Synthesis of Co-Doped Spinel LiMn2O4 Nanotubes as Cathodes for Li-Ion Batteries

Li-Xin Zhang,Yuan-Zhong Wang,Hong-Fang Jiu,Ya-Lei Wang,Yi-Xin Sun,Zhenzhong Li 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.2

Spinel Co-LiMn2O4 nanotubes have been synthesized via solid state reaction using α-MnO2 nanotubes as selftemplates. The as-prepared powders were investigated by XRD, TEM, and galvanostatic discharge/charge analysis. The optimal doping amount was confirmed by galvanostatic charge/discharge measurements. The results indicate that about 67% of initial capacity (115 mAh/g) of LiMn2O4 nanotubes can be retained after 50 cycles. For Co-LiMn2O4 nanotubes, the initial reversible capacity is 126.6 mAh/g and 100 mAh/g can be maintained after 50 cycles. The capacitance retention rate of Co-LiMn2O4 nanotubes is as high as 79%. These results indicate that the doping Co can effectively improve circle stability and electrochemical performance of LiMn2O4 nanotubes.

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Li, Qingwei,Chen, Fang,Zhao, Weili,Xu, Mingxiu,Fang, Benjie,Zhang, Yuelong,Duo, Liping,Jin, Yuqi,Sang, Fengting Korean Chemical Society 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near- IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gasliquid- solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

A Spectroscopic Study on Singlet Oxygen Production from Different Reaction Paths Using Solid Inorganic Peroxides as Starting Materials

Qingwei Li*,Fang Chen,Weili Zhao,Mingxiu Xu,Benjie Fang,Yuelong Zhang,Liping Duo,Yuqi Jin,Fengting Sang 대한화학회 2007 Bulletin of the Korean Chemical Society Vol.28 No.10

Using solid inorganic peroxides (including Li2O2, Na2O2, SrO2 and BaO2) as starting materials, three reaction paths for singlet oxygen (1O2) production were developed and studied. Their 1O2 emission spectra in the near-IR region and visible region from these reaction paths were simultaneously recorded by a near-IR sensitive Optical Multichannel Analyzer and a visible sensitive Optical Spectrum Analyzer, respectively. The comparison of their 1O2 emission spectra indicated that: (1) in term of the efficiency for 1O2 production, the gas-liquid-solid reaction path (in which Cl2 or HCl and H2O reacted with the solid inorganic peroxides suspension in CCl4) was prior to the gas-solid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides suspension in CCl4), but was inferior to the gas-liquid reaction path (in which Cl2 or HCl reacted with the solid inorganic peroxides solution in H2O or D2O); (2) the alkali metal peroxides (such as Li2O2 and Na2O2) was prior to the alkaline earth metal peroxides (such as SrO2 and BaO2) as the solid reactants, and Cl2 was favorable than HCl as the gas reactant in efficiency for 1O2 production in these reaction paths.

Purification and Characterization of Extracellular Inulinase from a Marine Yeast Pichia guilliermondii and Inulin Hydrolysis by the Purified Inulinase

Fang Gong,Tong Zhang,Jun Sheng,Jing Li,Xianghong Wang,Zhenming Chi 한국생물공학회 2008 Biotechnology and Bioprocess Engineering Vol.13 No.5

The extracellular inulinase of the marine yeast Pichia guilliermondii strain 1 was purified to homogeneity resulting in a 7.2-fold increase in specific inulinase activity. The molecular mass of the purified enzyme was estimated to be 50.0 kDa. The op-timal pH and temperature for the purified enzyme were 6.0 and 60C, respectively. The enzyme was activated by Mn²+, Ca²+, K+, Li+, Na+, Fe³+, Fe²+, Cu²+, and Co²+, but Mg²+, Hg²+, and Ag+ inhibited activity. The enzyme was strongly inhibited by phenylmethanesulphonyl fluoride (PMSF), iodoacetic acid, EDTA, and 1, 10-phenanthroline. The Km and Vmax values of the purified inulinase for inulin were 21.1 mg/mL and 0.08 mg/min, respectively. A large number of monosaccharides were de-tected after the hydrolysis of inulin. The deduced protein sequence from the cloned P. guilliermondii strain 1 inulinase gene contained the consensus motifs R-D-P-K-V-F-W-H and W-M-N-D-P-N-G, which are conserved among the inulinases from other microorganisms.

The preparation, performance and lithiation mechanism of cobalt-doped zinc oxide as a high performance anode material for LIB

Yue Li,WanWan Li,Minhua Fang,XiaoLin Yao,Chao Chen,Miao Shui,Jie Shu,Yuanlong Ren 한국물리학회 2017 Current Applied Physics Vol.17 No.8

Zn1-xCoxO (0 x 0.15) anode material was prepared by an easy polyacrylamide assisted sol-gel route. The successful replacement of Zinc by Cobalt within Cobalt content x 0.09 was confirmed by structural characterization. The introduction of Cobalt element greatly improved the electro-chemical performances of the matrix Zinc oxide. Without carbon coating, at the 20th cycle, Zn0.91Co0.09O anode still preserved a capacity a little bit more than 1000 mA h g1 and a capacity more than 600 mA h g1 was retained at the end of the 50th cycle. Better rate capability was also witnessed. The SEM, EIS at OCV, CV and in situ XRD were further carried out to elucidate the lithiation mechanism. The role Cobalt doping played can be summarized as follows: the stabilization of the Li2Zn phase, the minimization of charge transfer resistance and the enhanced reversibility of the reduction from metal oxide to metal.

중국어 상고음

李方桂 경희대학교 부설 비교문화연구소 1993 외대어문논총 Vol.- No.5

Systemic Family Therapy of Comorbidity of Anxiety and Depression with Epilepsy in Adolescents

Jing Li1,Xuefeng Wang,Huaqing Meng,Kebin Zeng,Fengying Quan,Fang Liu 대한신경정신의학회 2016 PSYCHIATRY INVESTIGATION Vol.13 No.3

ObjectiveaaThe aim of this study was to find if systemic family therapy (SFT) does work in anxiety and depression with epilepsy in adolescents (ADAE). Methodsaa104 adolescents with epilepsy, aged 13–20 years old, were included from December 2009 to December 2010, the enrolled patients were with anxiety [Hamilton Anxiety Scale (HAMA) score ≥14 points] or depression [Hamilton Depression Scale (HAMD) score ≥20 points]. The patients were randomly divided into the control group (n=52) treated with antiepileptic drugs (AED) and the intervention group (n=52) undergone Systemic Family Therapy (SFT) as well as AED. The AED improvements, anxiety and depression scores, Social Support Rating Scale (SSRS), Family Assessment Device (FAD) and scale of systemic family dynamics (SSFD) were observed after 3-month treatment. ResultsaaThe frequencies of epileptic seizures in intervention group was decreased much more significantly than the control group (4.22±3.54 times/month vs. 6.20±5.86 times/month, p=0.04); and the scores of anxiety (9.52±6.28 points vs. 13.48±8.47 points, p=0.01) and depression (13.86±9.17 points vs. 18.89±8.73 points, p=0.02) were significantly decreased than the control group; meanwhile, the family dynamics and family functions were significantly improved, and the social support was also increased (p<0.05). ConclusionaaSFT combined with AEDs had better efficacies than AEDs alone, not only the frequency of epileptic seizures was decreased, but also the patients’ anxiety and depression were improved, and the family dynamics, family functions and social support were improved.

沈德潛之詩論淺析

鄭莉芳 韓國外國語大學校 外國學綜合硏究센터 中國硏究所 2004 中國硏究 Vol.34 No.-

Ye Hsieh poetry theory evaluates me ancient poetry to Shen Dech'ien to have the important influence, therefore our minute from one, the poetry develops the source and course, varies directly the idea; Second, the gentle honest poem teaches the principle; Third, the poet creates the subjective condition and four, the poem law outlines these four parts to perform to elaborate, on the one hand explains Ye Hsiehshih theory, on the other hand also pointed out Shen inheriting with the development, understood the Shen poem discusses the basic connotation.

Preparation of lithium-doped NaV6O15 thin film cathodes with high cycling performance in SIBs

Xu Hai-Yan,Ruan Jun Hai,Liu Fang Lin,Li Dong-Cai,Zhang Feng-Jun,Wang Ai-Guo,Sun Dao-Sheng,오원춘 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.3

Lithium ions-doped NaV6O15 thin films have been prepared using a simple low temperature liquid phase deposition method and subsequent annealing process. X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), scanning elec- tron microscopy (SEM), and photoelectron spectroscopy (XPS) have been used to study the structural and physicochemical characteristics of the NaV6O15 film. The films were grown on the FTO conductive glass and used directly as an electrode of sodium ion batteries. The prepared lithium ions-doped NaV6O15 thin film electrodes showed an excellent cycling stability and discharge capacity, which may be attributed to the stability of the Li+ embedded into the gap between the V–O layers to maintain the structure and its stable β-phase structure transformed after the first cycle. The cycling stability greatly improved with increasing annealing temperature, while the discharge capacity decreased. The capacities of the film electrodes annealed at 400 °C and 450 °C maintained above 97% after 100 cycles. The lithium-doped NaV6O15 underwent a phase transition dur- ing the first charge/discharge cycle. The new transformed phase has perfect crystal structure stability undergoing insertion and deinsertion of Na+. Therefore, the lithium-doped NaV6O15 thin film possesses good cycling stability and is expected to be a promising thin film cathode for sodium-ion batteries.