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片层纤维V_(2)O_(5)·1.6H_(2)O干凝胶提升水系锌离子电池循环性能
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作者 刘丹 崔月 +2 位作者 裴彪 高海燕 赵永男 《工程科学学报》 EI CSCD 北大核心 2024年第3期438-446,共9页
水系锌离子电池凭借低成本和环境友好的特点具有极大的发展和应用前景.具有高比表面、分层、或快速离子导体结构的钒基材料是锌离子电池最具有前景的正极材料之一.如何改善钒基材料的长循环性能是亟待解决的问题之一.本文采用溶胶凝胶... 水系锌离子电池凭借低成本和环境友好的特点具有极大的发展和应用前景.具有高比表面、分层、或快速离子导体结构的钒基材料是锌离子电池最具有前景的正极材料之一.如何改善钒基材料的长循环性能是亟待解决的问题之一.本文采用溶胶凝胶法并冷冻干燥成功制备了V_(2)O_(5)·1.6H_(2)O干凝胶,利用X射线衍射仪、扫描电子显微镜对其物相和形貌进行了表征,发现制备的材料为V_(2)O_(5)·1.6H_(2)O,结晶相良好,且成片状纤维大孔结构.电化学测试表明,在0.1 A·g^(–1)电流密度下,首次放电比容量为388.4 mA·h·g^(–1),循环1000次后容量仍保持为129.7 mA·h·g^(–1),具有良好的长循环稳定性.在0.1、0.2、0.5、1、2和3 A·g^(-1)电流密度下,纤维状V2O5干凝胶表现出良好的倍率性能,放电比容量分别为388.4、338.5、282.9、239.1、194.4和165.9 mA·h·g^(–1),远高于商业化V2O5 (279.5、251.0、205.5、174.5、144.6和125.1 mA·h·g^(–1)).良好的电化学性能主要归功于结合水的支撑作用增大了层间距,在循环过程中材料具有良好的结构稳定性,避免了放电容量衰减;同时纤维片状结构缩短了锌离子的迁移路径.对充放电机理研究发现,在锌离子的嵌入脱出过程中伴随有碱式硫酸锌的生成与消失,且该过程可逆. 展开更多
关键词 锌离子电池 v_(2)o_(5)·1.6H_(2)o 正极材料 长循环性能 机理探究
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Building stabilized Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode enables an outstanding room‐/low‐temperature aqueous Zn‐ion batteries
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作者 Ao Wang Dai‐Huo Liu +9 位作者 Lin Yang Fang Xu Dan Luo Haozhen Dou Mengqin Song Chunyan Xu Beinuo Zhang Jialin Zheng Zhongwei Chen Zhengyu Bai 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期25-35,共11页
Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this ... Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials. 展开更多
关键词 aqueous zinc‐ion batteries Cu_(0.17)Mn_(0.03)v_(2)o_(5−□)·2.16H_(2)o oxygen defects room‐/lowtemperature performance stabilized nanostructure
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Polypyride intercalation boosting the kinetics and stability of V_(3)O_(7)·H_(2)O cathodes for aqueous zinc-ion batteries
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作者 Qingqing He Jie Bai +4 位作者 Mengda Xue Yanxin Liao Huayu Wang Mujun Long Lingyun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期361-370,I0007,共11页
V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)i... V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted VO-PPyd.The total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron conductivity.Furthermore,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and composition.More importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),respectively.VO-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs. 展开更多
关键词 v_(3)o_(7)·H_(2)o PoLYPYRIDINE Ion migration Electrical conductivity Aqueous zinc ion batteries DFT calculation
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棒状V_(3)O_(7)•H_(2)O电极材料的制备及印刷超级电容器
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作者 涂倩 王婧璐 +4 位作者 郑茵茵 林宝莹 张强 刘善培 陈良哲 《精细化工》 EI CAS CSCD 北大核心 2024年第5期1084-1091,1160,共9页
以V2O5为原料,利用溶剂热法一步制备了V_(3)O_(7)•H_(2)O纳米棒,采用SEM、XRD、EDS、XPS和FTIR对样品进行了测试。以V_(3)O_(7)•H_(2)O纳米棒为电极材料,探究了丝网印刷工艺对电极电化学性能的影响,将此电极组装超级电容器并评价了其电... 以V2O5为原料,利用溶剂热法一步制备了V_(3)O_(7)•H_(2)O纳米棒,采用SEM、XRD、EDS、XPS和FTIR对样品进行了测试。以V_(3)O_(7)•H_(2)O纳米棒为电极材料,探究了丝网印刷工艺对电极电化学性能的影响,将此电极组装超级电容器并评价了其电化学性能。结果表明,丝网印刷电极比电容可达268.0 F/g(电流密度为0.3 A/g),经过5000次循环后电容保持率为85.9%,优于涂抹电极的比电容(246.0 F/g)和电容保持率(68.0%),这得益于丝网印刷的油墨规则排列的结构。组装的纽扣超级电容器也表现出优异的电化学性能,比电容和电容保持率为134.2 F/g(0.5 A/g电流密度)和91.2%(5000次充放电循环),且当能量密度为22.0 W·h/kg时,功率密度最高可达4125.0 W/kg。 展开更多
关键词 七氧化三钒 纳米棒 丝网印刷 纽扣超级电容器 有机电化学
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核壳结构的V_(10)O_(24)·12H_(2)O@ACFC:一种高性能对称超级电容器电极材料
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作者 黄贤敏 李紫薇 +3 位作者 张晓妍 刘慧 高红艳 汪海 《材料导报》 CSCD 北大核心 2023年第21期17-24,共8页
超级电容器因功率密度高、循环寿命长等优点引起了众多学者的关注。为探索出一种低成本、易获得、高性能的电极材料,本工作以廉价易得的碳布为基材采用电化学刻蚀法使其活化,并以此为载体成功诱导了V_(2)O_(5)溶胶转化为凝胶,再经冷冻... 超级电容器因功率密度高、循环寿命长等优点引起了众多学者的关注。为探索出一种低成本、易获得、高性能的电极材料,本工作以廉价易得的碳布为基材采用电化学刻蚀法使其活化,并以此为载体成功诱导了V_(2)O_(5)溶胶转化为凝胶,再经冷冻干燥处理获得了在活化碳布表面包覆有V_(10)O_(24)·12H_(2)O超薄纳米片的复合材料,实现了在简易、温和的条件下制得具有核壳结构的电极材料。通过UV-Vis光谱揭示了这一吸附转化的过程,电化学活化的本质是在碳布上引入了含氧官能团且在表现出介孔特性的同时碳布的吸附性能也得到了增强。SEM、XRD结果表明该复合材料是以碳纤维为“内核”,以V_(10)O_(24)·12H_(2)O超薄纳米片为“外壳”的核壳结构。电化学测试表明,当电流密度为1 A/g时,该复合材料的比容量为488 F/g;以电流密度为5 A/g对该复合材料进行长循环测试,可获得初始比容量为256 F/g,且在循环初期容量不断增加,在10 000次循环后,容量保持率为100%(相比4 000次以后),其展现出超长的循环稳定性;在功率密度为1 875 W/kg下,该复合材料仍可输出20.1 Wh/kg的能量密度。优异的电化学性能得益于该电极材料核壳结构的协同作用,正是这种核壳结构成功地将发生在ACFC-1.0上的双电层电容行为与发生在V_(10)O_(24)·12H_(2)O超薄纳米片上的赝电容行为有机结合,为设计新的高性能超级电容器提供了可行方案。 展开更多
关键词 活化碳布 吸附 核壳结构 含氧官能团 v_(10)o_(24)·12H_(2)o超薄纳米片 超级电容器
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汉语成语的构式网络研究——以“V_(1)O_(1)+V_(2)O_(2)”类成语构式为例
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作者 田良斌 《现代语文》 2023年第9期58-65,共8页
以“V_(1)O_(1)+V_(2)O_(2)”类成语构式为例,构建该类构式的网络模型。研究发现,网络模型成员之间具有扩展关系和细化关系,但本质上都是一种范畴化关系。这种范畴化关系以原型范畴为基点,可以为扩展构式和细化构式提供允准。在构式网络... 以“V_(1)O_(1)+V_(2)O_(2)”类成语构式为例,构建该类构式的网络模型。研究发现,网络模型成员之间具有扩展关系和细化关系,但本质上都是一种范畴化关系。这种范畴化关系以原型范畴为基点,可以为扩展构式和细化构式提供允准。在构式网络中,扩展构式和细化构式在语义理解上都是转喻机制在起作用,而在具体的运作机制上则存在一定差异。通过“V_(1)O_(1)+V_(2)O_(2)”类成语构式的网络构建,以期为汉语成语教学、汉语成语词典编撰提供有益借鉴。 展开更多
关键词 构式网络 v_(1)o_(1)+v_(2)o_(2)” 成语构式 范畴化 转喻
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调控Cs_(3)Bi_(2)Br_(9)@V_(O)-In_(2)O_(3)S型异质结的费米能级和内建电场促进光生电荷分离和二氧化碳还原
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作者 张志洁 王雪盛 +2 位作者 唐慧玲 李德本 徐家跃 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第12期227-240,共14页
近年来,卤化物钙钛矿材料由于具有合适的能带结构和良好的可见光捕获能力,被广泛应用于光催化还原CO_(2).然而,单一的卤化物钙钛矿的载流子辐射复合严重,导致其电荷分离效率较低,并且对CO_(2)的捕获能力较差,进而限制了其在光催化领域... 近年来,卤化物钙钛矿材料由于具有合适的能带结构和良好的可见光捕获能力,被广泛应用于光催化还原CO_(2).然而,单一的卤化物钙钛矿的载流子辐射复合严重,导致其电荷分离效率较低,并且对CO_(2)的捕获能力较差,进而限制了其在光催化领域的实际应用.构建异质结被认为是解决单一半导体光催化剂光生载流子分离效率低等问题的有效策略.研究表明,S型异质结不仅可以实现光生载流子的有效分离,而且其独特的光生电荷传输路径还可以使异质结体系保留较强的氧化还原能力,利于光催化反应进行.本文以提高Cs_(3)Bi_(2)Br_(9)钙钛矿量子点的载流子分离效率和CO_(2)吸附能力为目标,构建了Cs_(3)Bi_(2)Br_(9)@V_(O)-In_(2)O_(3)(CBB@V_(O)-In_(2)O_(3))S型异质结,并探究了氧空位在该异质结光催化还原CO_(2)中的作用.首先,将Cs_(3)Bi_(2)Br_(9)钙钛矿量子点(PQD)嵌入到介孔In_(2)O_(3)基体中,构建了CBB@In_(2)O_(3)S型异质结.然后,将氧空位(V_(O))引入到异质结的还原型半导体(介孔In_(2)O_(3))中,增大了CBB和V_(O)-In_(2)O_(3)之间的费米能级(EF)差异,进而增强了CBB@V_(O)-In_(2)O_(3)S型异质结的内建电场.电子自旋共振谱、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-visDRS)等结果表明,In_(2)O_(3)中成功引入了氧空位.表面电荷密度和表面光电压测试结果表明,CBB@In_(2)O_(3)异质结的内建电场强度为单一CBB的4.07倍,而CBB@V_(O)-In_(2)O_(3)异质结的内建电场强度比单一的CBB提升了11.69倍,进一步证明在In_(2)O_(3)中引入氧空位可以增大两种材料的费米能级差异及内建电场强度.密度泛函理论(DFT)理论计算结果表明,氧空位的引入能够使In2O3的费米能级向上移动,使In_(2)O_(3)和CBB之间的费米能级差异增大,与实验结果相一致.这种增强的内建电场为光生载流子的定向迁移提供了更强的驱动力,从而有效提高了该S型异质结的电荷分离效率.采用UV-visDRS,Tauc曲线和莫特-肖特基图谱等分析了In_(2)O_(3)和CBB的能级结构,发现两种材料的能级位置交错排列,有利于形成S型异质结.瞬态吸收光谱、光辅助开尔文力显微镜和原位XPS等结果表明,该异质结的电荷转移模式为S型.该S型异质结的内建电场促进了电荷的高效分离,使得CBB@V_(O)-In_(2)O_(3)异质结表现出较好的光催化CO_(2)还原为CO的性能,其生成CO的产率为130.96μmolg-1h-1.此外,该CBB@V_(O)-In_(2)O_(3)S型异质结表现出良好的光催化稳定性,经过10次循环实验后,其催化CO_(2)还原的性能未发生明显的下降.通过原位漫反射红外傅立叶变换光谱研究了反应中间体和CO_(2)光转化途径.结合DFT计算发现,V_(O)-In_(2)O_(3)中的氧空位作为活性位点,能够优化反应中间体的配位模式,从而降低了光催化还原CO_(2)的活化能.综上所述,调控S型异质结的内建电场是提高异质结电荷分离效率、提升材料光催化性能的有效策略.本文构建了Cs_(3)Bi_(2)Br_(9)@V_(O)-In_(2)O_(3)(CBB@V_(O)-In_(2)O_(3))S型异质结,并探究了氧空位在该异质结光催化还原CO_(2)中的作用,为高效S型异质结光催化材料的设计提供了一种新思路,也为探索氧空位在S型异质结中的作用及人工光合成催化剂的制备提供一定参考. 展开更多
关键词 S型异质结 内建电场 氧空位 v_(o)-In_(2)o_(3) Cs_(3)Bi_(2)Br_(9)
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Platinum-Induced Pseudo-Zn-Air Reaction Massively Increases the Electrochemical Capacity of Aqueous Zn/V_(5)O_(12)·6H_(2)O Batteries
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作者 Gongzheng Yang Chengxin Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第4期596-602,共7页
How to effectively improve Zn^(2+)-storage properties is now becoming an urgent issue in the development of high-energy-density aqueous zinc-ion batteries.Here,a new method is proposed to massively increase the electr... How to effectively improve Zn^(2+)-storage properties is now becoming an urgent issue in the development of high-energy-density aqueous zinc-ion batteries.Here,a new method is proposed to massively increase the electrochemical capacity of aqueous Zn/V_(5)O_(12)·6H_(2)Obatteries.By adding a small amount of platinum(Pt,1.5 wt.%)and keeping other factors constant,the V_(5)O_(12)·6H_(2)O-Pt electrodes deliver a much higher specific capacity(440 m Ah g^(-1)at 500 m A g^(-1))than do V_(5)O_(12)·6H_(2)Oelectrodes(270 m Ah g^(-1)at500 m A g^(-1)).The structural and morphological evolution of V_(5)O_(12)·6H_(2)Oduring cycling results in Zn^(2+)ion insertion/extraction and the formation/disappearance of the zinc hydroxyl complex(Zn_(4)SO_(4)(OH)_(6)·5H_(2)O,ZHS),where the latter is closely related to the surface redox reaction,promoting Zn^(2+)ion stripping/plating on the Zn anode and consequently leading to extra electron transfer.Electrochemical tests in the absence of oxygen reveal that the Pt additive has no contribution and is even counterproductive to electric conductivity but favors remarkable enhancement of the pseudocapacitance.Accordingly,it is apparent that a strong causal relationship exists between Pt and the ZHS.In consideration of the catalytic application for oxygen reduction,Pt is expected to play a vital role in enhancing the electrochemical capacity through the pseudo-Zn-air reaction.This finding introduces a new strategy for achieving high-performance aqueous zinc-ion batteries. 展开更多
关键词 cathode PLATINUM pseudo-Zn-air reaction v_(5)o_(12)·6H_(2)o Zinc-ion battery
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钒-砷氧簇合物[Zn_(2)(dien)_(3)]_(1/2){[Zn_(2)(dien)_(3)]As_(6)V_(15)O_(42)}·2H_(2)O的合成与晶体结构表征
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作者 张雨薇 孙天一 《山东化工》 CAS 2021年第20期12-14,18,共4页
本文以氯化锌、五氧化二钒以及三氧化二砷为原料,合成了[Zn_(2)(dien)_(3)]_(1/2){[Zn_(2)(dien)_(3)]As_(6)V_(15)O_(42)}·2H_(2)O,讨论了其晶体结构并进行了结构表征。
关键词 [Zn_(2)(dien)_(3)]_(1/2){[Zn_(2)(dien)_(3)]As_(6)v_(15)o_(42)}·2H_(2)o 氯化锌 五氧化二钒 三氧化二砷
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从“一边VP_(1),一边VP_(2)”到“边V_(1)边V_(2)”四字格——压缩与降级 被引量:1
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作者 王天佑 《汉语学习》 CSSCI 北大核心 2021年第6期69-76,共8页
“边V_(1)边V_(2)”四字格是在“一边VP_(1),一边VP_(2)”等源格式的基础上逐步压缩而成的,机制为“保留主要成分、精减次要成分”。“边V_(1)边V_(2)”四字格的形成并未导致源格式的消亡,而是与其继续并存于现代汉语之中。“语言经济... “边V_(1)边V_(2)”四字格是在“一边VP_(1),一边VP_(2)”等源格式的基础上逐步压缩而成的,机制为“保留主要成分、精减次要成分”。“边V_(1)边V_(2)”四字格的形成并未导致源格式的消亡,而是与其继续并存于现代汉语之中。“语言经济原则”是促发“一边VP_(1),一边VP_(2)”及其相关格式走向压缩的源动力,而格式本身的结构、语义和韵律等因素则为压缩得以顺利实现准备了条件。“边V_(1)边V_(2)”四字格的形成是结构压缩的结果,而结构的压缩也导致了章法向句法(词法)以及小句向句法(词法)成分的降级。 展开更多
关键词 “一边vP_(1) 一边vP_(2)” “边v_(1)边v_(2)” 压缩 降级
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“NP_1+V_1+NP_1+的+N_1,NP_2+V_2+NP_2+的+N_2”格式初探
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作者 王佳慧 《现代语文(下旬.语言研究)》 2016年第6期95-96,共2页
本文对汉语中"NP_1+V_1+NP_1+的+N_1,NP_2+V_2+NP_2+的+N_2"此类格式进行初步探索,从形式到意义进行分析和解释,利于人们更好地认识该类结构,同时对该格式中真伪定语的问题进行讨论。
关键词 “NP_1+v_1+NP_1+的+N_1 NP_2+v_2+NP_2+的+N_2 真定语 伪定语
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Monoclinic Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O nanobelts/reduced graphene oxide:A novel high-capacity and long-life composite for potassium-ion battery anodes
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作者 Liming Ling Xiwen Wang +9 位作者 Yu Li Chenxiao Lin Dong Xie Min Zhang Yan Zhang Jinjia Wei Huajie Xu Faliang Cheng Chuan Wu Shiguo Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期140-151,I0005,共13页
Developing suitable anode materials for potassium-ion batteries(PIBs)remains a great challenge owing to the limited theoretical capacity of active materials and large radius of K+ion(1.38?).To solve these obstacles,by... Developing suitable anode materials for potassium-ion batteries(PIBs)remains a great challenge owing to the limited theoretical capacity of active materials and large radius of K+ion(1.38?).To solve these obstacles,by integrating the principles of multielectron transfer and rational porous crystal framework,we creatively propose the monoclinic Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O(CVO)as a novel anode for PIBs.Furthermore,inspired by the metastable nature of CVO under high temperature/pressure,we skillfully design a facile hydrothermal recrystallization strategy without the phase change and surfactants addition.Thus,for the first time,the porous composite of Cu_(3)(OH)_(2)V_(2)O_(7)·2H_(2)O nanobelts covered in situ by reduced graphene oxide(CVO NBs/r GO)was assembled,greatly improving the deficiencies of CVO.When used as a novel anode for PIBs,CVO NBs/r GO delivers large specific capacity(up to 551.4 m Ah g^(-1)at 50 m A g^(-1)),high-rate capability(215.3 m Ah g^(-1)at 2.5 A g^(-1))and super durability(203.6 m Ah g^(-1)at 500 m A g^(-1)even after 1000 cycles).The outstanding performance can be ascribed to the synergistic merits of desirable structural features of monoclinic CVO nanobelts and the highly conductive graphene 3D network,thus promoting the composite material stability and electrical/ionic conductivity.This work reveals a novel metal vanadate-based anode material for PIBs,would further motivate the subsequent batteries research on M_(3)(OH)_(2)V_(2)O_(7)-n H_(2)O(M;Co,Ni,Cu,Zn),and ultimately expands valuable fundamental understanding on designing other high-performance electrode materials,including the combined strategies of multielectron transfer with rational porous crystal framework,and the composite fabrication of 1D electrode nanostructure with conductive carbon matrix. 展开更多
关键词 Rational framework with multielectron transfer Novel potassium-ion batteries anode Hydrothermal recrystallization Cu_(3)(oH)_(2)v_(2)o_(7)·2H_(2)o nanobelts Conductive graphene 3D network Synergistic effect
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基于形式语义学研究维吾尔语句式NP_(1)+(NP_(2))+V_(2)+V_(1)的分化及形式语义规则
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作者 潘艳兰 《语言与翻译》 CSSCI 2021年第4期35-40,共6页
形式语义学是指将自然语言的语义转换成一个体系严密的形式化系统。本文采用了逻辑语义分析法,运用形式语言来实现对句式形式化的描写和分析,结合语言学、逻辑学、计算机科学,通过分析维吾尔语句式NP_(1)+(NP_(2))+V_(2)+V_(1),总结出... 形式语义学是指将自然语言的语义转换成一个体系严密的形式化系统。本文采用了逻辑语义分析法,运用形式语言来实现对句式形式化的描写和分析,结合语言学、逻辑学、计算机科学,通过分析维吾尔语句式NP_(1)+(NP_(2))+V_(2)+V_(1),总结出逻辑语义的表达式,推导出相应的Prolog语言,有利于维吾尔语学习者系统地掌握该句式的特点和规律。 展开更多
关键词 形式语义学 句式NP_(1)+(NP_(2))+v_(2)+v_(1) 形式语义规则
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类固定短语“V_(1)东V_(2)西”考察
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作者 麻柳赟 《闽西职业技术学院学报》 2022年第1期78-82,共5页
“V_(1)东V_(2)西”格式是介于固定短语和非固定短语之间的类固定短语,在现代汉语中使用频率高,能产性强。“V_(1)东V_(2)西”可以根据语义分为三类:并列类、转折类、顺承类,其中并列类“V_(1)东V_(2)西”数量最多,使用频率最高。作为... “V_(1)东V_(2)西”格式是介于固定短语和非固定短语之间的类固定短语,在现代汉语中使用频率高,能产性强。“V_(1)东V_(2)西”可以根据语义分为三类:并列类、转折类、顺承类,其中并列类“V_(1)东V_(2)西”数量最多,使用频率最高。作为类固定短语,“V_(1)东V_(2)西”的语用价值主要有形象性、主观大量、主观评价三个方面。 展开更多
关键词 类固定短语 v_(1)东v_(2)西” 语义分类 语用价值
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V_(2)O_(5)/Fe_(2)O_(3)@Ti O_(2)核壳微球NH_(3)-SCR过程中N_(2)O形成和抑制机制研究
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作者 刘玉中 《江西科学》 2021年第5期928-932,共5页
以商业P_(_(2))_(5)为硬模板,钒酸铵和硫酸铁铵为原料,采用水热法制备了Fe_(_(2))O_(3)/V_(_(2))O_(5)@Ti O_(_(2))核壳微球。通过改变Fe_(_(2))O_(3)和V_(_(2))O_(5)含量调节Fe_(_(2))O_(3)/V_(_(2))O_(5)@Ti O_(_(2))核壳微球NH_(3)... 以商业P_(_(2))_(5)为硬模板,钒酸铵和硫酸铁铵为原料,采用水热法制备了Fe_(_(2))O_(3)/V_(_(2))O_(5)@Ti O_(_(2))核壳微球。通过改变Fe_(_(2))O_(3)和V_(_(2))O_(5)含量调节Fe_(_(2))O_(3)/V_(_(2))O_(5)@Ti O_(_(2))核壳微球NH_(3)法选择性催化还原(NH_(3)-SCR)性能。研究结果表明:在相同温度下,NO转化率和N_(_(2))O生成率随V_(_(2))O_(5)含量的增加而增加。Fe_(_(2))O_(3)可以显著抑制N_(_(2))O生成,随Fe_(_(2))O_(3)含量的增加,N_(_(2))O生成率先降低后又增加,当V_(_(2))O_(5)和Fe_(_(2))O_(3)含量分别为1%和3%时,NO转化率最高而N_(_(2))O生成率最低,对环境的影响最小。 展开更多
关键词 v_(2)o_(5) Fe_(2)o_(3) 核壳微球 脱硝 No N_(2)o
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铜负载量对V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂脱硝协同汞氧化性能的影响
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作者 杨子文 宁占武 +1 位作者 淡默 梁全明 《山西化工》 2022年第4期1-3,共3页
采用浸渍法制备了系列Cu_(2)O-V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂,通过固定床反应器考察了不同Cu_(2)O负载量对V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂脱硝协同单质汞(Hg0)氧化性能的影响。结果表明,_(2)%Cu_(2)O的引入提高了催化剂的脱硝协... 采用浸渍法制备了系列Cu_(2)O-V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂,通过固定床反应器考察了不同Cu_(2)O负载量对V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂脱硝协同单质汞(Hg0)氧化性能的影响。结果表明,_(2)%Cu_(2)O的引入提高了催化剂的脱硝协同汞氧化性能。采用BET和XRD对催化剂进行分析,证实Cu_(2)O-V_(2)O_(5)-MoO_(3)/TiO_(2)催化剂良好的催化活性与其均匀分散的活性组分有关,与孔道结构没有明显的相关性。 展开更多
关键词 Cu_(2)o v_(2)o_(5)-Moo_(3)/Tio_(2)催化剂 脱硝 Hg0氧化
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La掺杂氧空位的α-Bi_(2)O_(3)电子结构和光学性质的第一性原理研究
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作者 熊智慧 孔博 +2 位作者 李志西 曾体贤 帅春 《人工晶体学报》 CAS 北大核心 2023年第1期98-104,共7页
基于第一性原理的方法研究了本征α-Bi_(2)O_(3)、La掺杂、氧空位掺杂和共掺杂体系的电子结构与光学性质,以期获得性能比较优异的α-Bi_(2)O_(3)光催化材料。研究结果表明:掺杂后,体系结构变形较小,其中氧空位(V_(O))掺杂和La-V_(O)共... 基于第一性原理的方法研究了本征α-Bi_(2)O_(3)、La掺杂、氧空位掺杂和共掺杂体系的电子结构与光学性质,以期获得性能比较优异的α-Bi_(2)O_(3)光催化材料。研究结果表明:掺杂后,体系结构变形较小,其中氧空位(V_(O))掺杂和La-V_(O)共掺杂体系的禁带宽度价带和导带同时下移且在禁带中引入杂质能级,说明掺杂可以减小电子从价带激发到导带所需能量,有利于电子的跃迁。特别是相对于氧空位单掺杂,La-V_(O)共掺杂使杂质能级向导带底靠近,这个倾向可能使该复合缺陷成为光生电子捕获中心的概率大于成为光生电子-空穴对复合中心的概率;同时,La-V_(O)共掺杂导致导带底附近的能带弯曲的曲率增大即色散关系增强,从而降低了电子的有效质量,加速电子的运动,因此,La-V_(O)共掺杂能大幅改善光生电子-空穴对的有效分离。另一方面La-V_(O)共掺杂在显著扩展可见光吸收范围的同时,还极大地增强了可见光吸收强度。因此,La-V_(O)共掺杂有效改善了α-Bi_(2)O_(3)的光催化活性。本研究为利用稀土离子掺杂改善其他光催化材料的性能提供了一个新的思路。 展开更多
关键词 α-Bi_(2)o_(3) 光催化材料 La-v_(o)共掺杂 氧空位 电子结构 光学性质 第一性原理
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Weakly Polarized Organic Cation-Modified Hydrated Vanadium Oxides for High-Energy Efficiency Aqueous Zinc-Ion Batteries
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作者 Xiaoxiao Jia Chaofeng Liu +2 位作者 Zhi Wang Di Huang Guozhong Cao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期169-186,共18页
Vanadium oxides,par-ticularly hydrated forms like V_(2)O_(5)·nH_(2)O(VOH),stand out as promising cathode candidates for aqueous zinc ion batteries due to their adjustable layered structure,unique electronic chara... Vanadium oxides,par-ticularly hydrated forms like V_(2)O_(5)·nH_(2)O(VOH),stand out as promising cathode candidates for aqueous zinc ion batteries due to their adjustable layered structure,unique electronic characteristics,and high theoretical capacities.However,challenges such as vanadium dissolution,sluggish Zn^(2+)diffusion kinetics,and low operating voltage still hinder their direct application.In this study,we present a novel vanadium oxide([C_(6)H_(6)N(CH_(3))_(3)]_(1.08)V_(8)O_(20)·0.06H_(2)O,TMPA-VOH),developed by pre-inserting trimethylphenylammonium(TMPA+)cations into VOH.The incorporation of weakly polarized organic cations capitalizes on both ionic pre-intercalation and molecular pre-intercalation effects,resulting in a phase and morphology transition,an expansion of the interlayer distance,extrusion of weakly bonded interlayer water,and a substantial increase in V^(4+)content.These modifications synergistically reduce the electrostatic interactions between Zn^(2+)and the V-O lattice,enhancing structural stability and reaction kinetics during cycling.As a result,TMPA-VOH achieves an elevated open circuit voltage and operation voltage,exhibits a large specific capacity(451 mAh g^(-1)at 0.1 A g^(-1))coupled with high energy efficiency(89%),the significantly-reduced battery polarization,and outstanding rate capability and cycling stability.The concept introduced in this study holds great promise for the development of high-performance oxide-based energy storage materials. 展开更多
关键词 Zinc-ion battery vanadium oxide v_(2)o_(5)·nH_(2)o Pre-intercalation Interlayer engineering
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Dependence of Structure and Magnetic Properties on Annealing Temperature in Fe(72.5)Cu1Nb2V2Si(13.5)B9 Alloy
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作者 Chunyan BAN, Wenqing GAO, Guiyi ZENG, Qixian BA Hualin ZENGSchool of Materials and Metallurgy, Northeastern University, Shenyang 110004, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第3期285-286,共2页
The magnetic properties of Fe_(72.5)Cu_1Nb_2V_2Si_(13.5)B_9 alloy are investigated from an amorphous to a nanocrystalline and complete crystalline state. The sample annealed at 550℃ for 0.5 h shows a homogeneous nano... The magnetic properties of Fe_(72.5)Cu_1Nb_2V_2Si_(13.5)B_9 alloy are investigated from an amorphous to a nanocrystalline and complete crystalline state. The sample annealed at 550℃ for 0.5 h shows a homogeneous nanocrystalline structure and presents excellent soft magnetic properties. When the specimens were annealed at a temperature above 600℃, the magnetic properties are obviously deteriorated because the grain size grows up, exceeding the exchange length. 展开更多
关键词 Fe_(72.5)Cu_1Nb_2v_2Si_(13.5)B_9 alloy Soft magnetic properties Nanocrystalline structure Grain size
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Weaker Interactions in Zn^(2+)and Organic Ion-pre-intercalated Vanadium Oxide toward Highly Reversible Zinc-ion Batteries 被引量:3
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作者 Feng Zhang Xiucai Sun +7 位作者 Min Du Xiaofei Zhang Wentao Dong Yuanhua Sang Jianjun Wang Yanlu Li Hong Liu Shuhua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第4期620-630,共11页
Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinet... Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability. 展开更多
关键词 [N(CH_(3))_(4) Zn]v_(8)o_(20)·3.8H_(2)o nanosheets aqueous zinc-ion battery highly reversible organic ion pre-intercalation zinc-carbon interactions
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