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In situ electrochemical reconstruction of Sr2Fe1.45Ir0.05Mo0.5O6-δ perovskite cathode for CO2 electrolysis in solid oxide electrolysis cells

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National Science Review 2023年第9期10卷 37-45页

作者： Yuxiang Shen Tianfu Liu Rongta. Li Houfu Lv Na ta.Xiaomin Zhang Yuefeng song Qingxue Liu Weicheng Feng Guoxiong Wang Xinhe Bao Sta.e Key Laboratory of Cata.ysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Solid oxide electrolysis cells provide a practical solution for the direct conversion of CO2to other chemicals(***),however,an in-depth mechanistic understa.ding of the dynamic reconstruction of active sites for perovskite cathodes during CO2 electrolysis remains a great ***,we identify that iridium-doped Sr2Fe1.45Ir0.05Mo0.5O6-δ(SFIrM) perovskite displays a dynamic electrochemical reconstruction feature during CO 2 electrolysis with abundant exsolution of highly dispersed IrFe alloy nanoparticles on the SFIrM *** in situ reconstructed IrFe@SFIrM interfaces deliver a current density of 1.46 A cm-2while mainta.ning over 99% CO Faradaic efficiency,representing a 25.8%improvement compared with the Sr2Fe1.5Mo0.5O6-δ*** situ electrochemical spectroscopy measurements and density functional theory calculations suggest that the improved CO2electrolysis activity originates from the facilita.ed formation of carbonate intermediates at the IrFe@SFIrM *** work may open the possibility of using an in situ electrochemical poling method for CO2electrolysis in practice.

关键词： solid oxide electrolysis cell CO2 electrolysis, in situ electrochemical reconstruction meta./perovskite interface carbonate intermediates

High-resolution bone microstructure imaging based on ultrasonic frequency-domain full-waveform inversion

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Chinese Physics B 2021年第1期30卷 295-310页

作者： Yifang Li Qinzhen Shi Ying Li Xiaojun song Chengcheng Liu Dean ta.Weiqi Wang Department of Electronic Engineering Fudan UniversityShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina Academy for Engineering and Technology Fudan UniversityShanghaiChina

The main challenge in bone ultrasound imaging is the large acoustic impedance contrast and sound velocity differences between the bone and surrounding soft tissue. It is difficult for conventional pulse-echo modalities to give accurate ultrasound images for irregular bone boundaries and microstructures using uniform sound velocity assumption rather than getting a prior knowledge of sound speed. To overcome these limita.ions, this paper proposed a frequency-domain fullwaveform inversion(FDFWI) algorithm for bone quantita.ive imaging utilizing ultrasonic computed tomography(USCT).The forward model was calculated in the frequency domain by solving the full-wave equation. The inverse problem was solved iteratively from low to high discrete frequency components via minimizing a cost function between the modeled and measured data. A quasi-Newton method called the limited-memory Broyden–Fletcher–Goldfarb–Shanno algorithm(L-BFGS) was utilized in the optimization process. Then, bone images were obta.ned based on the estimation of the velocity and density. The performance of the proposed method was verified by numerical examples, from tubular bone phantom to single dista. fibula model, and finally with a dista. tibia-fibula pair model. Compared with the high-resolution peripheral quantita.ive computed tomography(HR-p QCT), the proposed FDFWI can also clearly and accurately presented the wavelength scaled pores and trabeculae in bone images. The results proved that the FDFWI is capable of reconstructing high-resolution ultrasound bone images with sub-millimeter resolution. The parametric bone images may have the potential for the diagnosis of bone disease.

关键词： quantita.ive imaging full-waveform inversion bone microstructure ultrasonic computed tomography high resolution

Trace elements in tree rings and their environmenta. effects: A case study in Xi’an City

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Science China Earth Sciences 2009年第4期52卷 504-510页

作者： LIU Yu ta.WeiYuan BAO TingYi YANG ZengYue song HuiMing LIU Na WANG WeiPing ZHANG HongYi ZHANG Wei AN ZhiSheng School of Human Settlement and Civil Engineering Xi’an JiaoTong UniversityXi’an 710049China The Institute of Environment and Reproduction Department of UrologyThe Fourth Military Medical UniversityXi’an 710038China Institute of Earth Environment Chinese Academy of SciencesXi’an 710075China

Using wet digested method and ICP mass spectrometer, we analyzed the concentration of five trace elements (Cd, Mn, P, Zn and Pb) for the tree rings from both urban and suburbs of Xi'an. At the urban sampling site, one Chinese mahogany (Toona sinensis) disc and one phoenix tree (Firmiana simplex) disc were sampled from a steelworks in Xi'an City. At the suburb site, a Chinese mahogany disc was collected from a village in the south of the City. In addition, some soils near the roots of the sampled trees were collected. The analysis results indicate that the concentration of each of the five elements in annual rings has a positive correlation with the production of the steelworks. Sta.istical calculations show that Pb and Mn elements were sta.le without lag effects. That means these two elements do not move between rings. Cd displayed one year moving, P two years and Zn three years. These results are quite similar to those found by other methods.

关键词： Xi’an tree rings element concentration environmenta. conta.inants

Detection of long bones based on Barker code excited ultrasonic guided waves

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Chinese Journal of Acoustics 2014年第2期33卷 136-146页

作者： ZHANG Huilin song Xiaojun ta.De'an Department of Electronic Engineering Fudan University

Single pulse excited ultrasonic guided wave surfers high attenuation during the propagation in long *** results in small amplitude and low signal-to-noise ratio（SNR）of measured ***,the Barker code excita.ion is introduced into long bone detection to improve the quality of received signals,due to its efficiency in increasing amplitude and *** simulation and in vitro experiment were performed,and the results were decoded by the weighted match filter（WMF） and the finite impulse response- least squares inverse filter（FIRLSIF）,*** comparison between the results of Barker code excita.ion and sine pulse excita.ion was *** 13-bit Barker code excita.ion,WMF produced 13 times larger amplitude than sine pulse excita.ion,while FIR-LSIF achieved higher peak-sidelobe-level（PSL） of -63.59 dB and better performance in noise *** results show that the Barker code excited guided waves have the potential to be applied to the long bone detection.

关键词： code Detection of long bones based on Barker code excited ultrasonic guided waves FIR

Nonlinear inversion of ultrasonic guided waves for in vivo evaluation of cortical bone properties

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Chinese Physics B 2022年第7期31卷 371-378页

作者： Xiaojun song Tii Fan Jundong Zeng Qin-Zhen Shi Qiong Huang Meilin Gu Petro Moilanen Yi-Fang Li Dean ta Center for Biomedical Engineering Fudan UniversityShanghai 200433China College of Electronics and Information engineering Shanghai University of Electric PowerShanghai 200090China Department of Physics University of HelsinkiHelsinkiFinland Academy for Engineering and Technology Fudan UniversityShanghai 200433China

Ultrasonic guided waves(UGWs),which propagate throughout the entire thickness of cortical bone,are attractive for the early diagnosis of ***,this is challenging due to the impact of soft tissue and the inherent difficulties related to multiparametric inversion of cortical bone quality factors,such as cortical thickness and bulk wave ***,in this research,a UGW-based multi-parameter inversion algorithm is developed to predict strength-related *** simulation,a free plate(cortical bone)and a bilayer plate(soft tissue and cortical bone)are used to validate the proposed *** inversed cortical thickness(CTh),longitudinal velocity(V_(L))and transverse velocity(V_(T))are in accordance with the true *** four bovine cortical bone plates were used in in vitro *** with the reference values,the relative errors for cortical thickness were 3.96%,0.83%,2.87%,and 4.25%,*** the in vivo measurements,UGWs are collected from the tibias of 10 *** theoretical dispersion curves depicted by the estimated parameters(V_(T),V_(L),CTh)match well with the extracted experimenta. *** comparison with dual-energy x-ray absorptiometry,our results show that the estimated transverse velocity and cortical thickness are highly sensitive to ***,these two parameters(CTh and V_(T))of long bones have potential to be used for diagnosis of bone sta.us in clinical applications.

关键词： ultrasonic guided waves inversion algorithm transverse velocity bone evaluation

ta.Doped Sb2Te Allows Ultrafast Phase-Change Memory with Excellent High-Temperature Operation Characteristics

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Nano-Micro Letters 2021年第2期13卷 221-231页

作者： Yuan Xue Shuai Yan Shilong Lv Sannian song Zhita.g song Sta.e Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

Phase-change memory(PCM)has considerable promise for new applications based on von Neumann and emerging neuromorphic computing ***,a key challenge in harnessing the advanta.es of PCM devices is achieving high-speed operation of these devices at elevated temperatures,which is critical for the efficient processing and reliable storage of data.at full ***,we report a novel PCM device based on ta.doped antimony telluride(Sb2Te),which exhibits both high-speed characteristics and excellent high-temperature characteristics,with an operation speed of 2 ns,endurance of >106 cycles,and reversible switching at 140℃.The high coordination number of ta.and the strong bonds between ta.and Sb/Te atoms contribute to the robustness of the amorphous structure,which improves the thermal ***,the small grains in the three-dimensional limit lead to an increased energy efficiency and a reduced risk of layer segregation,reducing the power consumption and improving the long-term *** findings for this new ta.Sb2Te material system can facilita.e the development of PCMs with improved performance and novel applications.

关键词： Phase-change memory High speed ta High-temperature operation

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广西武宣县盘龙铅锌矿矿床成矿地球化学特征

中国有色金属学报 2012年第2期22卷 533-545页

作者：薛静戴塔根付松武中南大学有色金属成矿预测教育部重点实验室长沙410083 中南大学地球科学与信息物理学院长沙410083

盘龙铅锌矿是桂中地区典型的大型铅锌矿床,它位于广西大瑶山西侧铅锌多金属成矿带南段。为了确定该矿床成矿流体性质和成矿金属来源,作者系统研究了矿床的稀土元素、硫铅同位素和流体包裹体特征。研究结果表明：矿石和围岩的ΣREE较低,L... 详细信息

盘龙铅锌矿是桂中地区典型的大型铅锌矿床,它位于广西大瑶山西侧铅锌多金属成矿带南段。为了确定该矿床成矿流体性质和成矿金属来源,作者系统研究了矿床的稀土元素、硫铅同位素和流体包裹体特征。研究结果表明：矿石和围岩的ΣREE较低,LREE富集、具有显著的Eu正异常和弱Ce负异常;矿石的硫同位素除了3件黄铁矿样品δ34SV-CDT为-17.90×10-3、-21.00×10-3和-20.60×10-3,其它硫化物的δ34SV-CDT均落在-7.10×10-3~7.70×10-3之间,而重晶石样品的δ34SV-CDT较高,达17.3×10-3~29.2×10-3,硫同位素分析结果暗示成矿物质来源于深源岩浆和泥盆纪海水的共同作用;矿石的铅同位素206Pb/204Pb、207Pb/204Pb和208Pb/204Pb的变化范围分别为18.376~18.438、15.763~15.852和38.763~39.060,相似的铅同位素特征表明矿石的来源和成因是均一的、相同的,并且具有壳源的特征。喷流成矿期成矿流体均一温度属中-低温（166~289℃）、低盐度（4.01%~14.07%）、低密度（0.804~0.955 g/cm3）,成矿流体属于H2O-NaCl体系。综合矿床地质和地球化学特征可知,盘龙铅锌矿床显著区别于MVT型铅锌矿,应属于海底喷流-沉积型铅锌矿。

关键词：喷流-沉积稀土元素硫铅同位素铅同位素成矿流体大瑶山铅锌多金属成矿带

阿拉善-华北北缘晚古生代-早中生代岩浆作用:对古亚洲洋俯冲-闭合过程的制约

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岩石学报 2025年第1期41卷 66-90页

作者：曾浩宋东方肖文交李普庆中国科学院地质与地球物理研究所岩石圈演化与环境演变全国重点实验室北京100029 中国科学院地球科学研究院北京100029 中国科学院新疆生态与地理研究所干旱区生态安全与可持续发展全国重点实验室乌鲁木齐830011 中国科学院大学地球与行星科学学院北京100049

位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学... 详细信息

位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学和Lu-Hf同位素分析。锆石U-Pb定年表明这些岩体分别形成于早二叠世(283±3Ma、273±5Ma、272±5Ma)和中三叠世(238±3Ma)。早二叠世岩体以石英闪长岩和闪长玢岩为主,富集轻稀土与大离子亲石元素,亏损高场强元素Nb、ta.,Hf同位素显著亏损(-4.0~+15.6)。它们可能是由俯冲板片流体交代地幔楔部分熔融形成的基性岩浆经分离结晶演化而成。中三叠世侵入体为花岗闪长岩,轻重稀土元素强烈分异,锆石ε_(Hf)(t)值均为正值(+5.0~+8.5),可能代表了碰撞造山阶段新生下地壳物质部分熔融的产物。在此基础之上,本文系统收集并分析了阿拉善-华北北缘地区晚古生代-早中生代岩浆岩的时空分布规律与地球化学特征,以限定其构造背景与深部动力学过程。结合前人研究成果提出:石炭纪时期,古亚洲洋向南俯冲至阿拉善-华北克拉通之下并不断向北后撤;至早二叠世,俯冲板片转变为前进式俯冲,整体处于挤压环境,发育大规模岩浆活动与弧背前陆盆地;早-中三叠世,古亚洲洋闭合,阿拉善-华北克拉通沿索伦缝合带与北侧的中亚弧增生体系发生碰撞-拼贴。

关键词：阿拉善华北北缘晚古生代-早中生代古亚洲洋俯冲-闭合

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling Gong Xiang-Li Zhong Hong-Jia song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resista.t tetrahedral amorphous carbon（ta.C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta.C,denoted as（Ti/ta.C）_n,using arc ion plating.A multi-layer structure in conjunction with sta.e cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no sta.e cooling is applied to 0.35 when sta.e cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obta.ned（Ti/ta.C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta.C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and mainta.ns excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta.C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

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