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      • KCI등재

        White-Matter Hyperintensities and Lacunar Infarcts Are Associated with an Increased Risk of Alzheimer’s Disease in the Elderly in China

        Shuai Ye,Shuyang Dong,Jun Tan,Le Chen,Hai Yang,Yang Chen,Zeyan Peng,Yingchao Huo,Juan Liu,Mingshan Tang,Yafei Li,Huadong Zhou,Yong Tao 대한신경과학회 2019 Journal of Clinical Neurology Vol.15 No.1

        Background and Purpose This study investigated the contribution of white-matter hyperintensities (WMH) and lacunar infarcts (LI) to the risk of Alzheimer’s disease (AD) in an elderly cohort in China. Methods Older adults who were initially cognitively normal were examined with MRI at baseline, and followed for 5 years. WMH were classified as mild, moderate, or severe, and LI were classified into a few LI (1 to 3) or many LI (≥4). Cognitive function was assessed using the Mini Mental State Examination and the Activities of Daily Living scale. Results Among the 2,626 subjects, 357 developed AD by the end of the 5-year follow-up period. After adjusting for age and other potential confounders, having only WMH, having only LI, and having both WMH and LI were associated with an increased risk of developing AD compared with having neither WMH nor LI. Moderate and severe WMH were associated with an increased risk of developing AD compared with no WMH. Furthermore, patients with many LI had an increased risk of developing AD compared with no LI. Conclusions Having moderate or severe WMH and many LI were associated with an increased risk of developing AD, with this being particularly striking when both WMH and LI were present.

      • KCI등재

        Aqueous Processing and Effects of V2O5 on Microwave Dielectric Properties of Multilayer Li1.075Nb0.625Ti0.45O3 Ceramics

        Shaochun Li,Yongjuan Geng,Tiejun Zhao,Zuquan Jin,Peng Zhang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.1

        In the present work, we report the development of an aqueous tape casting method and a low temperature co-firing process for fabrication of multilayer Li1.075Nb0.625Ti0.45O3 microwave dielectric ceramics. A co-binder, consisting of polyvinyl acetate latex (PVAc) and polyvinyl alcohol (PVA), was used to prepare aqueous Li1.075Nb0.625Ti0.45O3 tapes. PVA addition increased the tape flexibility and adhesiveness but resulted in decreased tensile strength. Rheological tests indicated that the aqueous ceramic slurry exhibited a typical shear thinning behavior without thixotropy, suitable for tape casting. Scanning electron microscopy (SEM) studies revealed that the green tapes have a defect-free surface and that the multilayer ceramics sintered at 900°C have a fine plate like, grainy microstructure of uniform size. At lower temperatures, increased densification rates were achieved by addition of V2O5 to Li1.075Nb0.625Ti0.45O3 ceramics. The saturated bulk densities and dielectric constants (εr) of Li1.075Nb0.625Ti0.45O3 multilayer ceramics affected by lower sintering temperatures with an increase in V2O5 doping, and then an improvement in the quality factor (Q × f value) of the samples was achieved at the lower sintering temperatures. As a result, the εr of 64.9 and the Q × f value of 8800 GHz were obtained in the sample with an addition of 3 wt. % V2O5, sintered at a temperature of 900°C. No reaction was observed between the ceramic and silver layers when sliver inner-electrode, was sintered with ceramic tapes at 900°C.

      • KCI등재

        Mechanism and process for the extraction of lithium from the high magnesium brine with N,N-bis(2-ethylhexyl)-2-methoxyacetamide in kerosene and FeCl3

        Lianmin Ji,Licheng Zhang,Dong Shi,Xiaowu Peng,Jinfeng Li,Yuze zhang,Taoshan Xu,Lijuan Liao 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.113 No.-

        The degradation of TBP has become a stumbling block to the industrial continuous production of lithiumchloride extraction from brines with high Mg/Li ratio by solvent extraction. To develop a more stable andmore efficient extraction system, a novel amide system, containing newly synthesized extractant N,N-bis(2-ethylhexyl)-2-methoxyacetamide (NBEHMOA), FeCl3 6H2O and sulfonated kerosene, was proposed inthis work. Compared with TBP and N523, NBEHMOA extracted Li+ and H+ in the sequence of TBP ˃NBEHMOA ˃ N523 and N523 ˃ TBP ˃ NBEHMOA respectively. The solution containing 5.5 mol/L LiCland 0.5 mol/L HCl was used as the eluent in the scrubbing process. A Li+ extraction efficiency of 96.7%and 22.31 g/L Li+ in the stripping solution were achieved by the whole process with counter-currenttwelve stages. The extraction mechanism investigated via FT-IR spectroscopy illustrated that the metalions Fe3+ and Li+ were mainly coordinated by the carbonyl C = O in NBEHMOA. This novel amide systemcan successfully achieve the cascade extraction effect for lithium, Li/Mg separation and avoid the generationof phase interface objects through counter-current extraction of lithium from brine at a lower acidity. This work provided a novel extraction system to recover lithium from the higher magnesium/lithiumratio brines.

      • A Novel Molecular Grading Model: Combination of Ki67 and VEGF in Predicting Tumor Recurrence and Progression in Non-invasive Urothelial Bladder Cancer

        Chen, Jun-Xing,Deng, Nan,Chen, Xu,Chen, Ling-Wu,Qiu, Shao-Peng,Li, Xiao-Fei,Li, Jia-Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

        Purpose: To assess efficacy of Ki67 combined with VEGF as a molecular grading model to predict outcomes with non-muscle invasive bladder cancer (NMIBC). Materials: 72 NMIBC patients who underwent transurethral resection (TUR) followed by routine intravesical instillations were retrospectively analyzed in this study. Univariate and multivariate analyses were performed to confirm the prognostic values of the Ki67 labeling index (LI) and VEGF scoring for tumor recurrence and progression. Results: The novel molecular grading model for NMIBC contained three molecular grades including mG1 (Ki67 $LI{\leq}25%$, VEGF $scoring{\leq}8$), mG2 (Ki67 LI>25%, VEGF $scoring{\leq}8$; or Ki67 $LI{\leq}25%$, VEGF scoring > 8), and mG3 (Ki67 LI > 25%, VEGF scoring > 8), which can indicate favorable, intermediate and poor prognosis, respectively. Conclusions: The described novel molecular grading model utilizing Ki67 LI and VEGF scoring is helpful to effectively and accurately predict outcomes and optimize personal therapy.

      • KCI등재

        In-pile tritium release behavior and the post-irradiation experiments of Li4SiO4 fabricated by melting process

        Zhao Linjie,Yang Mao,Xiao Chengjian,Gong Yu,Ran Guangming,Chen Xiaojun,Li Jiamao,Yue Lei,Chen Chao,Hou Jingwei,Wang Heyi,Long Xinggui,Peng Shuming 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.1

        Understanding the tritium release and retention behavior of candidate tritium breeder materials is crucial for breeder blanket design. Recently, a melt spraying process was developed to prepare Li4SiO4 pebbles, which were subsequently subjected to the in-pile tritium production and extraction platform in China Mianyang Research Reactor (CMRR) to investigate their in-situ tritium release behavior and irradiation performance. The results demonstrate that HT is the main tritium release form, and adding hydrogen to the purge gas reduces tritium retention while increasing the HT percent in the purge gas. Post-irradiation experiments reveal that the irradiated pebbles darken in color and their grains swell, but the mechanical properties remain largely unchanged. It is concluded that the tritium residence time of Li4SiO4 made by melt spraying method at 467 ◦C is approximately 23.34 h. High-density Li4SiO4 pebbles exhibit tritium release at relatively low temperatures (<600 ◦C) that is mainly controlled by bulk diffusion. The diffusion coefficient at 525 ◦C and 550 ◦C is 1.19 × 10 11 cm2/s and 5.34 × 10 11 cm2/s, respectively, with corresponding tritium residence times of 21.3 hours and 4.7 hours.

      • KCI등재후보

        Preparation and Dieletrical Properties of Li1.075Nb0.625Ti0.45O3 Powders by Hydrothermal Method

        Shaochun Li,Yongjuan Geng,Tiejun Zhao,Peng Zhang 대한금속·재료학회 2012 ELECTRONIC MATERIALS LETTERS Vol.8 No.4

        A hydrothermal method has been developed and shown to be effective for the preparation of Li1.075Nb0.625Ti0.45O3(LNT) nano-particles. Hydrothermal reaction temperature was in the range from 120°C - 200°C. The crystalline structure and morphology of the prepared particles have been characterized by x-ray diffraction and scanning electron microscopy. Results indicate that hydrothermal temperature had a great effect on the phase formation and morphology of the particles. The prepared powders crystallized at 140°C, and the pure LNT phase was formed at 180°C. The size of LNT particles increased with increasing reaction temperature, and plate-like LNT particles with thickness of 15 - 30 mm and a diameter of 80 - 200 mm were obtained at 200°C. It was found that LNT powders synthesized at 180°C gave the LNT ceramics the highest microwave dielectric properties (εr = 66, Q×f = 8946 GHz) due to good crystallization and low particle size.

      • Nano/Microstructured Silicon-Graphite Composite Anode for High-Energy-Density Li-Ion Battery

        Li, Peng,Hwang, Jang-Yeon,Sun, Yang-Kook American Chemical Society 2019 ACS NANO Vol.13 No.2

        <P>With the ever-increasing demand for lithium-ion batteries (LIBs) with higher energy density, tremendous attention has been paid to design various silicon-active materials as alternative electrodes due to their high theoretical capacity (ca. 3579 mAh g<SUP>-1</SUP>). However, totally replacing the commercially utilized graphite with silicon is still insurmountable owing to bottlenecks such as low electrode loading and insufficient areal capacity. Thus, in this study, we turn back to enhanced graphite electrode through the cooperation of modified silicon via a facile and scalable blending process. The modified nano/microstructured silicon with boron doping and carbon nanotube wedging (B-Si/CNT) can provide improved stability (88.2% retention after 200 cycles at 2000 mA g<SUP>-1</SUP>) and high reversible capacity (∼2426 mAh g<SUP>-1</SUP>), whereas the graphite can act as a tough framework for high loading. Owing to the synergistic effect, the resultant B-Si/CNT-graphite composite (B-Si/CNT@G) shows a high areal capacity of 5.2 mAh cm<SUP>-2</SUP> and excellent cycle retention of 83.4% over 100 cycles, even with ultrahigh active mass loading of 11.2 mg cm<SUP>-2</SUP>,which could significantly surpass the commercially used graphite electrode. Notably, the composite also exhibits impressive application in Li-ion full battery using 2 mol % Al-doped full-concentration-gradient Li[Ni<SUB>0.76</SUB>Co<SUB>0.09</SUB>Mn<SUB>0.15</SUB>]O<SUB>2</SUB> (Al2-FCG76) as the cathode with excellent capacity retention of 82.5% even after 300 cycles and an outstanding energy density (8.0 mWh cm<SUP>-2</SUP>) based on the large mass loading of the cathode (12.0 mg cm<SUP>-2</SUP>).</P> [FIG OMISSION]</BR>

      • Superior lithium/potassium storage capability of nitrogen-rich porous carbon nanosheets derived from petroleum coke

        Li, Peng,Hwang, Jang-Yeon,Park, Sang-Min,Sun, Yang-Kook The Royal Society of Chemistry 2018 Journal of Materials Chemistry A Vol.6 No.26

        <P>Tremendous attention has been paid to carbon-based anodes for lithium-ion and potassium-ion batteries. Nevertheless, conferring high energy storage properties using carbon-based anodes is still challenging. In this work, petroleum coke-based nitrogen-doped porous carbon nanosheets (N-PCSs) were prepared using carbon nitride (g-C3N4) as both a template and nitrogen source and tested as advanced anode materials. The as-obtained N-PCSs constructed through an <I>in situ</I> solid-state approach possess both high capacity and excellent cycling stability. High capacities were obtained for Li-ion and K-ion batteries (407 mA h g<SUP>−1</SUP> after 500 cycles at 3720 mA g<SUP>−1</SUP> and 206 mA h g<SUP>−1</SUP> after 300 cycles at 1000 mA g<SUP>−1</SUP>, respectively); these are some of the best capacities for carbon-based electrode materials and could be ascribed to the unique microstructure of the anodes, <I>i.e.</I>, nanosheet morphology, developed porosity, ultrahigh nitrogen doping, and a high level of disorder. Meanwhile, this study represents a milestone for high-value utilization of petroleum coke and other kinds of heavy oil.</P>

      • KCI등재

        Effect of CeO2 addition on crystallization and thermophysical properties of Li2O-ZnO-SiO2 glass-ceramics

        Ruixue Li,Qian Zhang,Xingliang Peng,Weizhen Liu 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.1

        The effect of CeO2 addition on crystallization and thermo-physical properties of lithium zinc silicate (LZS) glasses containingLi2O-ZnO-SiO2-Al2O3-Na2O-P2O5 was investigated. The changes of CeO2 contents (2-8 wt.%) had an obvious influence on thetransition temperatures (Tg) and crystallization temperatures (Tc) of LZS glass-ceramics, and they increased with CeO2 contentincreasing. According to XRD analysis, CeO2 promoted the formation of cristobalite and β-spodumene crystals, and β-spodumene increased obviously. As the CeO2 content increasing, the microstructure and microhardness (being 6.88 Gpa at 880oC) of glass-ceramics had great changes. The average thermal expansion coefficient (20 - 450 oC) showed first increasing thendecreasing, having a wide range. The maximum of thermal expansion coefficient was obtained when the glass-ceramicscontained 4 wt.% CeO2, being 175×10−7 K−1 (at 700 oC) and 178×10−7 K−1 (at 880 oC) respectively. Excellent thermo-physicalproperties indicate the glass has greater potential application, such as being used as sealing glass.

      • SCISCIESCOPUS

        Low-Temperature Carbon Coating of Nanosized Li<sub>1.015</sub>Al<sub>0.06</sub>Mn<sub>1.925</sub>O<sub>4</sub> and High-Density Electrode for High-Power Li-Ion Batteries

        Lee, Min-Joon,Lho, Eunsol,Bai, Peng,Chae, Sujong,Li, Ju,Cho, Jaephil American Chemical Society 2017 NANO LETTERS Vol.17 No.6

        <P>Despite their good intrinsic rate capability, nanosized spinel cathode materials cannot fulfill the requirement of high electrode density and volumetric energy density. Standard carbon coating cannot be applied on spinel materials due to the formation of oxygen defects during the high-temperature annealing process. To overcome these problems, here we present a composite material consisting of agglomerated nanosized primary particles and well-dispersed acid treated Super P carbon black powders, processed below 300 degrees C. In this structure, primary particles provide fast lithium ion diffusion in solid state due to nanosized diffusion distance. Furthermore, uniformly dispersed acid-treated Super P (ASP) in secondary particle facilitates lower charge transfer resistance and better percolation of electron. The ASPLMO material shows superior rate capability, delivering 101 mAh g 1 at 300 degrees C-rate at 24 degrees C, and 75 mAh g(-1) at 100 degrees C-rate at 10 degrees C. Even after 5000 cycles, 86 mAh ClIcan be achieved at 30 degrees C=rate at 24 degrees C, demonstrating very competitive full-cell performance.</P>

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