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61.
The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb10.8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscopy and UV-Vis absorption spectrum. Metronidazole is very stable and is difficult to degrade under UV irradiation. K6Nb10.8O30 photocatalyst cannot degrade metronidazole without UV irradiation and shows very high photo-catalytic activity for the degradation of metronidazole under UV irradiation. The photocatalytic degradation rate of metronidazole increased with increasing the dosage of K6Nb10.8O30 photocatalyst. The photocatalytic degradation reaction of metronidazole by nio-bate K6Nb10.8O30 follows the first-order kinetic equation.  相似文献   
62.
TiO_2 has been widely studied as an important electrode material for electrochemical energy storage.Understanding its relationship between textural properties and electrochemical characteristics is essential to boosting its practical performances. Herein, Aeroxide P25 TiO_2 nanoparticles annealing at different temperatures(400–600 °C) were investigated as an anode material of lithium ion battery. Their evolution in crystal phase and microstructural characteristics were characterized by XRD and BET surface analysis, and their lithium storage properties in half-cells were evaluated by various electrochemical analyses, including cyclic voltammetry, cycling testing, and electrochemical impedance spectroscopy. It was found that the lithium storage properties were critically dependent on the size of TiO_2 anode materials. Pristine P25 initially exhibited the highest initial discharge specific capacity due to its smallest particle size; however, rapid capacity loss occurred during extended cycling. The annealing process was found to effectively enhance the cycling stability of TiO_2 although possessing a large particle size and smaller surface area. Typically, P400 showed the best performances in cycling stability, capacity retention ratio, and rate capability, which is mainly attributed to the synergistic effect of high crystallinity, reasonable particle size, and less internal resistance. This study provides an instance of optimizing the textural properties of metal oxides for advanced LIB anode material applications.  相似文献   
63.
在100K~450K范围内,研究了铌酸钡铅(PBN)系统中三种不同组份晶体的介电和热释电性.它们都在较宽的温度范围内具有中等大小的热释电系数、较小的介电常数和较高的热释电探测优值,是适合于热释电探测器的材籽.  相似文献   
64.
通过固相反应法预合成0.94(K0.5Na0.5)NbO3-0.06LiNbO3(KNLN6)无铅压电陶瓷粉体。采用X线衍射仪(XRD)、扫描电子显微镜/能谱仪(SEM/EDS)和高分辨透射电子显微镜(HRTEM)对KNLN6试样进行性能表征。结果表明:按化学计量配比合成的KNLN6粉体中含有K3Li2Nb5O15(KLN)第二相;Na2CO3摩尔分数过量5%时,可有效地消除第二相KLN,从而获得单一钙钛矿结构的KNLN6粉体,同时,粉体的预烧温度降低了50℃;在1070℃下烧结2 h制备的Na2CO3过量5%的无铅压电陶瓷中,KNLN6晶体具有A位无序的单一正交钙钛矿结构,晶粒呈立方体状,平均尺寸约为10μm。  相似文献   
65.
介绍了系统管理总线SMBus(Smart Manegement Bus),SMBus是智能电池系统SBS(Smart Baterry System)中升压单元、电池充电单元、控制单元、锂动力电池及外设之间的互连接口,它能对电池的充放电电流、电压、温度、容量等重要参数进行监测和控制。  相似文献   
66.
采用固相法合成LiFePO4和LiFePO4/C复合材料,研究了蔗糖分解的碳包覆对LiFePO4材料性能的影响.XRD检测纯LiFePO4为单一的橄榄石相,而LiFePO4/C复合材料中出现高导电物质Fe2P相;SEM显示样品的粒径均在1μm以下,包覆碳样品的晶粒更小,但出现团聚现象.此方法合成的纯LiFePO4初始容量高达136.6 mAh/g.Fe2P的存在使LiFePO4材料的大电流放电能力得到提高.  相似文献   
67.
SiO_x/graphite anodes have attracted considerable attention in recent years due to their high specific capacity.Unfortunately,a thick solid-electrolyte-interface,which is produced by the decomposition of carbonate-based electrolytes,impedes the diffusion of lithium ions and significantly limits the rate performance of this interesting anode for practical applications.In this work,a LiNO_3additive was introduced during the preparation of an anode electrode paste.The results of SEM,ex and in situ XRD and XPS showed that LiNO_3decomposed into LiN_xO_yand Li_3N,which deposited on the anode surface during the first discharge process.Due to the high ionic conductivity of LiN_xO_yand Li_3N,the rate performance of the SiO_x/graphite anode was significantly improved,showing a specific capacity nearly three times higher than that without the additive.In addition,the decomposition of the electrolyte during cycling was also suppressed by the LiN_xO_yand Li_3N inorganic salts because of their low electronic conductivity and superior robustness.Our approach is facile and easy to scale up,which will be of great significance for the commercialization of SiO_x/graphite anodes.  相似文献   
68.
A core-shell structural composite was synthesized with lithium terephthalate(Li2C8H4O4) coated on spinel Li4Ti5O12(LTO). The composite displays a capacity of about 200 mA h g-1 and a good rate capability with two charge/discharge platforms at 1.55 and 0.8 V. The excellent cycling performance of the composite is attributed to the successful combination of high cycling stability of LTO and high specific capacity of Li2C8H4O4. In addition, an interesting phenomena is observed for the first time for this composite which is that lithium ions transfer between LTO and Li2C8H4O4 at a fast speed. This is investigated in details via the asymmetric charge/discharge measurement and cyclic voltammogram(CV).The LTO/Li2C8H4O4 composite may have potential applications to be used as an anode material for the electric vehicle batteries, which is shallowly charged/discharged at ordinary times using the charge/discharge platform of LTO and fully charged/discharged at emergency to release the extra high capacity from Li2C8H4O4.  相似文献   
69.
Summary A single i.p. injection of lithium chloride (5–7.5 moles/g b.wt) in mice caused a 70–80% decrease in renal, cardiac and splenic ornithine decarboxylase (ODC) activity within 1 h, whereas pulmonary ODC activity was unaffected. Lithium chloride did not have any effect on ODC activity in vitro when added to homogenates of the tissues studied. We suggest that the effect of lithium on ODC activity is not direct, but mediated via e.g. hormonal or nervous influence.This study was supported by grants from the Swedish Medical Research Council (04X-02212, 14X-00028), and the Faculty of Medicine, University of Lund (Sweden).  相似文献   
70.
以分析纯的BaCO3,SrCO3,Nb2O5,H38O3和SiO2粉末为原料,采用传统的固相合成法制备添加50BaO-4082O3-10SiO2玻璃(物质的量比)的Sro.3Ba0.7Nb2O6(即SBN70)陶瓷.采用X线衍射仪(XRD)、扫描电子显微镜(SEM)和阻抗分析仪研究添加玻璃对SBN70陶瓷的烧结和介电性能的影响.研究结果表明;随着玻璃含量的增加,陶瓷样品的相对密度先增大后减小;当玻璃含量为5%(质量分数,下同)时,样品的密度达到最大值;添加玻璃降低了陶瓷的烧结温度,于1 250℃时添加5%玻璃的SBN70陶瓷已烧结致密,陶瓷的平均晶粒尺寸约2 μm,晶粒呈短柱状结构;当玻璃含量增大时,晶粒尺寸呈增大趋势;当玻璃添加量≤5%时,样品仍为单相四方钨青铜结构;当含量为10%时,出现了第二相SrB4O7;随着玻璃含量的增加,SBN70衍射峰的位置先移向低角度后移向高角度,而居里温度T0逐渐降低,从195℃下降到25℃左右;随玻璃含量的增加,最大介电常数εmax呈先减小后增大的变化趋势,而介电损耗tan δ则随玻璃含量的增大而减小;添加玻璃的SBN70陶瓷具有弥散相变特性,其弥散系数γ随添加玻璃含量的增加而增大.  相似文献   
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