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Nano Research 2022年第10期15卷 8962-8971页

作者： Fangya Guo Yongfan Xie youxiang zhang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Ni/Li exchange is a detrimental effect on electrochemical performances for high-Ni cathode materials(LiNi_(x)Co_(y)Mn_(z)O_(2),x≥0.6).Adjusting Li-excess degree has been proved to be an effective way to optimize Ni/Li exchange in the ***,until now,how the Ni/Li exchange and thus the structural properties is affected by the Li-excess has not been understood and clearly elucidated in the ***,a feasible strategy is utilized to optimize Ni/Li exchange and the amount of anti-Li^(+)in LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) by mixing Ni_(0.8)Co_(0.1)Mn_(0.1)(OH)_(2) precursor with different amounts of lithium sources during *** was found that morphology and phase stability of the material can be tuned with moderate excessive *** 10%Li-excess,LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) exhibits an initial discharge capacity of 211.5 mAh·g^(–1) at 0.1 C and maintains 93.3%of its initial capacity after 100 cycles at 1 *** technologies were used to characterize the materials and it shows that the formation of broader Li slab space,decreased anti-Ni^(2+)in Li layer,and gradient distribution of Ni3+in the surface is contributed to moderate Li-excess in the *** Li slab space facilitates diffusion of Li^(+),decreased antisite-Ni^(2+)and gradient distribution of Ni3+in materials surfaces optimizes the Ni/Li *** on these results,we thus believe that it is the moderate Li-excess in material that optimized the electrochemical performance of high-Ni cathode materials.

关键词： Ni-rich cathodes Ni/Li exchange Li-excess structural stability cycling stability

Low-temperature strategy to synthesize single-crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) with enhanced cycling performances as cathode material for lithium-ion batteries

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Nano Research 2022年第3期15卷 2052-2059页

作者： Fangya Guo Yongfan Xie youxiang zhang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

With high reversible capacities of more than 200 mAh/g,Ni-rich layered oxides Li[Ni_(x)Co_(y)Mn_(1–x–y)]O_(2)(x≥0.6)serve as the most promising cathode materials for lithium-ion batteries(LIBs).However,the anisotropic lattice volume changes linked to theirα-NaFeO_(2)structured crystal grains bring about poor cycle performances for conventionally produced NCM *** deal with these issue,single-crystalµm-sized LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods was synthesized by a hydrothermal *** with conventional synthesis methods,these LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods were calcined at a low temperature with excessive lithium sources,which not only reduces the sintering temperature but also ensures the mono-dispersed micrometer-scaled particle *** used as the cathode material for LIBs,the as-prepared LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),with ordered layered-structure and low degree of cation mixing,shows excellent electrochemical *** sintered at 750°C with 50%Li-excess,the cathode material delivered an initial discharge capacity of 226.9 mAh/g with Coulombic efficiency of 91.2%at 0.1 C(1 C=200 mA/g)in the voltage range of 2.8‒4.3 *** charge-discharged at 1 C for 100 cycles,discharge capacity of 178.1 mAh/g with the capacity retention of 95.1%are still *** cycling stability at high cut-off voltage is also *** superior electrochemical properties should be related to the monodispersed micron scaled morphology which not only decreases the contact area between electrode and electrolyte but also mitigates the formation of *** low-temperature strategy of synthesizing single-crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods should be able to provide a feasible method for synthesizing other single-crystal Ni-rich cathode materials with excellent electrochemical performances for LIB.

关键词： lithium ions batteries cathode excessive lithium single crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)

Mitigation of voltage decay in Li-rich layered oxides as cathode materials for lithium-ion batteries

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Nano Research 2020年第1期13卷 151-159页

作者： Wenhui Hu youxiang zhang Ling Zan Hengjiang Cong College of Chemistry and Molecular Sciences Wuhan UniversityWuhan430072China Shenzhen Research Institute of Wuhan University Shenzhen518000China

Lithium-rich layered oxides(LLOs)have been extensively studied as cathode materials for lithium-ion batteries(LIBs)by researchers all over the world in the past decades due to their high specific capacities and high charge-discharge ***,as cathode materials LLOs have disadvantages of significant voltage and capacity decays during the charge-discharge *** was shown in the past that fine-tuning of structures and compositions was critical to the performances of this kind of *** this report,LLOs with target composition of Li1.17Mn0.50Ni0.24Co0.09O2 were prepared by carbonate co-precipitation method with different pH values.X-ray powder diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscope(TEM),and electrochemical impedance spectroscopies(EIS)were used to investigate the structures and morphologies of the materials and to understand the improvements of their electrochemical *** the pH values increased from 7.5 to 8.5,the Li/Ni ratios in the compositions decreased from 5.17 to 4.64,and the initial Coulombic efficiency,cycling stability and average discharge voltages were gained ***,the material synthesized at pH=8.5 delivered a reversible discharge capacity of 263 mAhg−1 during the first cycle,with 79.0%initial Coulombic efficiency,at the rate of 0.1 C and a superior capacity retention of 94%after 100 cycles at the rate of 1 ***,this material exhibited an initial average discharge voltage of 3.65 V,with a voltage decay of only 0.09 V after 50 charge-discharge *** improved electrochemical performances by varying the pH values in the synthesis process can be explained by the mitigation of layered-to-spinel phase transformation and the reduction of solid-electrolyte interface(SEI)*** hope this work can shed some light on the alleviation of voltage and capacity decay issues of the LLOs cathode materials.

关键词： lithium ion batteries cathode lithium-rich layered oxides voltage decay Li1.17Mn0.50Ni0.24Co0.09O2

Spinel-layered integrate structured nanorods with both high capacity and superior high-rate capability as cathode material for lithium-ion batteries

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Nano Research 2017年第2期10卷 556-569页

作者： Huibing He Hengjiang Cong Ya Sun Ling Zan youxiang zhang College of Chemistry and Molecular Sciences Wuhan University Wuhan 430072 China

Spinel phase LiMn2O4 was successfully embedded into monoclinic phase layered- structured Li2MnO3 nanorods, and these spineMayered integrate structured nanorods showed both high capacities and superior high-rate capabilities as cathode material for lithium-ion batteries （LIBs）. Pristine Li2MnO3 nanorods were synthesized by a simple rheological phase method using α-MnO2 nanowires as precursors. The spinel-layered integrate structured nanorods were fabricated by a facile partial reduction reaction using stearic acid as the reductant. Both structural characterizations and electrochemical properties of the integrate structured nanorods verified that LiMn2O4 nanodomains were embedded inside the pristine Li2MnO3 nanorods. When used as cathode materials for LIBs, the spineMayered integrate structured Li2MnO3 nanorods （SL-Li2MnO3） showed much better performances than the pristine layered-structured Li2MnO3 nanorods （L-Li2MnO3）. When charge-discharged at 20 mA.g-1 in a voltage window of 2.0-4.8 V, the SL-Li2MnO3 showed discharge capacities of 272.3 and 228.4 mAh.g-1 in the first and the 60th cycles, respectively, with capacity retention of 83.8%. The SL-Li2MnO3 also showed superior high-rate performances. When cycled at rates of 1 C, 2 C, 5 C, and 10 C （1 C = 200 mA-g-1） for hundreds of cycles, the discharge capacities of the SL-Li2MnO3 reached 218.9, 200.5, 147.1, and 123.9 mAh-g-1, respectively. The superior performances of the SL-Li2MnO3 are ascribed to the spineMayered integrated structures. With large capacities and superior high-rate performances, these spinel-layered integrate structured materials are good candidates for cathodes of next-generation high-power LIBs.

关键词： lithium-ion batteries cathode layered-spinel integrated structure Li2MnO3 nanorods

变模量弹塑性强度折减法及其在边坡稳定分析中的应用

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岩石力学与工程学报 2009年第7期28卷 1506-1512页

作者：杨光华张玉成张有祥广东省水利水电科学研究院广东广州510610 武汉大学土木建筑工程学院湖北武汉430072 中国建筑第三工程局有限公司湖北武汉430070

目前用于边坡稳定性分析的数值方法中的强度折减法通常是仅对强度参数进行折减,且采用的是理想弹塑性模型。该方法主要用于求解边坡的安全系数,由于其在弹性阶段是按线弹性且对弹性模量不折减,故未能充分考虑屈服前岩土体的非线性,采用... 详细信息

目前用于边坡稳定性分析的数值方法中的强度折减法通常是仅对强度参数进行折减,且采用的是理想弹塑性模型。该方法主要用于求解边坡的安全系数,由于其在弹性阶段是按线弹性且对弹性模量不折减,故未能充分考虑屈服前岩土体的非线性,采用这种理想弹塑性模型的强度折减法计算所的变形偏小。基于Duncan-Chang非线性本构模型,提出在弹性阶段对弹性模量也进行折减的变模量弹塑性模型强度折减法,可以获得更符合实际的变形场,模量的变化是依据简化的非线性本构模型来实现的。通过与条形基础沉降的理论解和原位压板试验结果对比,证实了新方法在获得合理位移场方面的合理性。将其初步应用于边坡工程的变形计算,并希望由此进一步建立变形与安全系数的关系,以便于更合理地进行现场变形监控。如果采用变形突变来确定安全系数,理想弹塑性模型的强度折减法更明显一些。因此,建议采用理想弹塑性模型的强度折减法确定安全系数,采用变模量弹塑性模型强度折减法确定变形场。

关键词：边坡工程强度折减法边坡稳定分析变形计算本构模型

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相邻线路盾构施工对既有隧道的影响

岩石力学与工程学报 2009年第A02期28卷 3945-3951页

作者：姚捷杨光华张玉成张有祥武汉大学土木建筑工程学院湖北武汉430072 广东省水利水电科学研究院广东广州510610

在刚度迁移原理的基础上,提出求解各施工步影响的沉降差值法,由单步增量求得相邻线路盾构施工对既有隧道影响全量。对某市地铁隧道的后施工线路盾构推进过程进行仿真计算,发现后施工隧道所产生之塌落拱拱脚作用在临近既有隧道斜上方这... 详细信息

在刚度迁移原理的基础上,提出求解各施工步影响的沉降差值法,由单步增量求得相邻线路盾构施工对既有隧道影响全量。对某市地铁隧道的后施工线路盾构推进过程进行仿真计算,发现后施工隧道所产生之塌落拱拱脚作用在临近既有隧道斜上方这一受力机制,得到单施工步引起的既有线路管片最大环向拉应力值为0.13MPa,最大累积附加拉应力为0.857MPa;结合对考虑拼接缝的既有隧道管片受力状态的分析,找到裂缝隔片产生在连接块上的重要内在原因。研究成果丰富了模拟相邻巷道施工影响的仿真计算方法,并对城市地铁隧道等类似工程在设计和施工中预防裂缝出现具有一定的指导意义。

关键词：隧道工程双线盾构隧道开裂三维有限元沉降差值法累积影响

零售企业信息技术应用成熟度对可持续供应链绩效的作用机制

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商业经济研究 2022年第17期 126-129页

作者：王帅张友祥东北师范大学经济与管理学院吉林长春130117 吉林省科技金融研究中心吉林长春130028

零售企业的发展依赖于零售产业链的整体经营状态,只有零售产业链上所有企业均达到最佳状态,零售企业才能居于市场领先地位。因此,零售企业间的竞争早已不只是企业间的竞争,更是供应链间的竞争。零售企业要真正实现可持续发展,不仅要保... 详细信息

零售企业的发展依赖于零售产业链的整体经营状态,只有零售产业链上所有企业均达到最佳状态,零售企业才能居于市场领先地位。因此,零售企业间的竞争早已不只是企业间的竞争,更是供应链间的竞争。零售企业要真正实现可持续发展,不仅要保持企业自身可持续,更要保证供应链可持续,所以可持续供应链管理与绩效应运而生。基于此,本文探究了零售企业信息技术应用成熟度对可持续供应链绩效的作用机制,旨在引导零售企业重视信息技术应用,从而实现对供应链的高效管理。得到如下结论:信息技术应用成熟度对于信息技术能力匹配以及可持续供应链绩效均起到显著促进作用;信息技术能力匹配对于可持续供应链绩效起到显著促进作用;信息技术能力匹配在信息技术应用成熟度与可持续供应链绩效之间起到部分中介作用。

关键词：信息技术应用成熟度零售企业可持续供应链能力匹配

Long-term Modulation of the Immune System by Perinatal Nutrition

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Long-term Modulation of the Immune System by Perinatal Nutri...

中国动物学会兽类学分会第六届会员代表大会暨学术讨论会

作者： DENG Kaidong zhang youxiang (College of Biological Resources and Environmental Science, Jishou University, Jishou, Hunan 416000)

＜正＞Nutrition during perinatal period is particularly critical for the development and function of the immune system than adulthood nutrition, and the relationship between early nutrition and diseases in later life has been established. In humans and laboratory animals, the plasticity of metabolic function in foetuses or neonates enables them to adapt to malnutrition for survival;however, such an adaptation, as usually evidenced by retarded

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论房价调控及政府的责任

当代经济研究 2008年第12期 54-55页

作者：曲世军张友祥东北师范大学马克思主义研究院吉林长春130024

近年来我国房地产市场存在泡沫,"房价——收入比"远远超出国际公认的合理水平。高商品房空置率表明我国房地产市场泡沫严重。我国房地产市场的融资结构单一,过度依赖银行;地方政府存在推动房价上涨的内在冲动,商品房开发建设成本增加;... 详细信息

近年来我国房地产市场存在泡沫,"房价——收入比"远远超出国际公认的合理水平。高商品房空置率表明我国房地产市场泡沫严重。我国房地产市场的融资结构单一,过度依赖银行;地方政府存在推动房价上涨的内在冲动,商品房开发建设成本增加;房地产的炒作与投机普遍。中央政府应履行宏观调控的责任,加大住房供应结构的调整力度,规范地方政府行为,财政、货币政策双管齐下,严厉打击房地产市场的过度投机行为。

关键词：房价房地产泡沫房地产市场房价调控政府责任

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关于基坑规程中围护结构变形计算的探讨

湖南科技大学学报（自然科学版） 2018年第3期33卷 39-46页

作者：张有祥周宏磊北京市勘察设计研究院有限公司

《建筑基坑支护技术规程》（JGJ120）中弹性支点法首先计算围护结构的变形,然后再根据围护结构的变形计算锚杆轴力和围护结构的内力.然而在计算围护结构变形时存在3个方面的不足：首先,如何合理的考虑预应力锚杆刚度及其随开挖深度的变... 详细信息

《建筑基坑支护技术规程》（JGJ120）中弹性支点法首先计算围护结构的变形,然后再根据围护结构的变形计算锚杆轴力和围护结构的内力.然而在计算围护结构变形时存在3个方面的不足：首先,如何合理的考虑预应力锚杆刚度及其随开挖深度的变化规律;其次,施加预应力工况下的变形计算模型合理性;最后,土方开挖前后的变形均为独立受力体系的总变形而非变形增量之和等.通过分析这些不足之处及其相应的解决方案,可使基坑围护结构变形计算更合理、更符合实际变形,使变形计算过程和原理更清晰,有助于基坑支护设计人员对围护结构变形计算结果的理解和合理应用.

关键词：围护结构变形主动土压力预应力刚度