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Li4-xSbxSn1-xS4 solid solutions for air-stable solid electrolytes

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Journal of Energy Chemistry 2020年第2期29卷 171-176页

作者： Zhuoran zhang jianxing zhang Yulong Sun Huanhuan Jia Linfeng Peng Yunyang zhang Jia Xie State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringWuhan 430074HubeiChina State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

The sulfide solid electrolytes have the characteristics of high ionic conductivity and low grain boundary resistance, which make them suitable for bulk-type all-solid-state batteries. However, most of them suffer from poor stability in air. Here, we explore the air stable sulfide solid electrolytes in Li4-xSbxSn1-xS4 system. The solid solutions of Li4-xSbxSn1-xS4(0 ≤ x ≤ 0.5) can be formed in Li4-xSbxSn1-xS4 system. Li3.8 Sb0.2 Sn0.8 S4 achieves the highest ionic conductivity of 3.5 × 10-4 S cm-1 in this system,which is 5 times as that of Li4 Sn S4 and 3 orders of magnitude higher than that of Li3 Sb S4, respectively. Li3.8 Sb0.2 Sn0.8 S4 crystallizes into the same structure with high ionic conductivity phase of β-Li3 PS4. Moreover, Li3.8 Sb0.2 Sn0.8 S4 owns good stability in humid air. Matching with LiCoO2 and Li4 Ti5 O12,Li3.8 Sb0.2 Sn0.8 S4 exhibits the potential to be applied in all-solid-state batteries.

关键词： Solid electrolyte Air stable sulfide Li4SnS4,β-Li3PS4 All-solid-state battery

STGNN-LMR:A Spatial–Temporal Graph Neural Network Approach Based on sEMG Lower Limb Motion Recognition

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Journal of Bionic Engineering 2024年第1期21卷 256-269页

作者： Weifan Mao Bin Ma Zhao Li jianxing zhang Yizhou Lu Zhuting Yu Feng zhang Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 101408China University of Science and Technology of China Hefei 230026China Shanghai Zhongyan Jiuyi Technology Co. Ltd.Shanghai 201821China Academy of Military Science Bejing 100091China

Lower limb motion recognition techniques commonly employ Surface Electromyographic Signal(sEMG)as input and apply a machine learning classifier or Back Propagation Neural Network(BPNN)for ***,this artificial feature engineering technique is not generalizable to similar tasks and is heavily reliant on the researcher’s subject *** contrast,neural networks such as Convolutional Neural Network(CNN)and Long Short-term Memory Neural Network(LSTM)can automatically extract features,providing a more generalized and adaptable approach to lower limb motion *** this approach overcomes the limitations of human feature engineering,it may ignore the potential correlation among the sEMG *** paper proposes a spatial–temporal graph neural network model,STGNN-LMR,designed to address the problem of recognizing lower limb motion from multi-channel ***-LMR transforms multi-channel sEMG into a graph structure and uses graph learning to model spatial–temporal *** 8-channel sEMG dataset is constructed for the experimental stage,and the results show that the STGNN-LMR model achieves a recognition accuracy of 99.71%.Moreover,this paper simulates two unexpected scenarios,including sEMG sensors affected by sweat noise and sudden failure,and evaluates the testing results using hypothesis *** to the experimental results,the STGNN-LMR model exhibits a significant advantage over the control models in noise scenarios and failure *** experimental results confirm the effectiveness of the STGNN-LMR model for addressing the challenges associated with sEMG-based lower limb motion recognition in practical scenarios.

关键词： Lower limb motion recognition Exoskeleton sEMG.Graph neural network Noise Sensor failure

Excitonic complexes and optical gain in two-dimensional molybdenum ditelluride well below the Mott transition

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Light(Science & Applications) 2020年第1期9卷 1647-1656页

作者： Zhen Wang Hao Sun Qiyao zhang Jiabin Feng jianxing zhang Yongzhuo Li Cun-Zheng Ning Department of Electronic Engineering Tsinghua University100084 BeijingChina Frontier Science Center for Quantum Information 100084 BeijingChina Beijing National Research Center for Information Science and Technology 100084 BeijingChina School of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85287USA

Semiconductors that can provide optical gain at extremely low carrier density levels are critically important for applications such as energy efficient ***,all current semiconductor lasers are based on traditional semiconductor materials that require extremely high density levels above the so-called Mott transition to realize optical *** new emerging 2D materials provide unprecedented opportunities for studying new excitonic physics and exploring new optical gain mechanisms at much lower density levels due to the strong Coulomb interaction and co-existence and mutual conversion of excitonic ***,we report a new gain mechanism involving charged excitons or trions in electrically gated 2D molybdenum ditelluride well below the Mott *** combined experimental and modelling study not only reveals the complex interplay of excitonic complexes well below the Mott transition but also establishes 2D materials as a new class of gain materials at densities 4-5 orders of magnitude lower than those of conventional semiconductors and provides a foundation for lasing at ultralow injection levels for future energy efficient photonic ***,our study could help reconcile recent conflicting results on 2D materials:While 2D material-based lasers have been demonstrated at extremely low densities with spectral features dominated by various excitonic complexes,optical gain was only observed in experiments at densities several orders of magnitude higher,beyond the Mott *** believe that our results could lead to more systematic studies on the relationship between the mutual conversion of excitonic species and the existence of optical gain well below the Mott transition.

关键词： optical complexes transition

Automatic segmentation of gas plumes from multibeam water column images using a U-shape network

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Journal of Oceanology and Limnology 2023年第5期41卷 1753-1764页

作者： Fanlin YANG Feng WANG Zhendong LUAN Xianhai BU Sai MEI jianxing zhang Hongxia LIU College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Ocean Geomatics Ministry of Natural ResourcesQingdao 266590China Key Laboratory of Marine Geology and Environment Center of Deep Sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266237China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

Cold seeps are widely developed on the seabed of continental margins and can form gas plumes due to the upward migration of methane-rich *** detection and automatic segmentation of gas plumes are of great significance in locating and studying the cold seep system that is usually accompanied by hydrate layers in the subsurface.A multibeam echo-sounder system(MBES)can record the complete backscatter intensity of the water column,and it is one of the most effective means for detecting cold ***,the gas plumes recorded in multibeam water column images(WCI)are usually blurred due to the interference of the complicated water environment and the sidelobes of the MBES,making it difficult to obtain the effective ***,based on the existing UNet semantic segmentation network,this paper proposes an AP-UNet network combining the convolutional block attention module and the pyramid pooling module for the automatic segmentation and extraction of gas *** experiments are conducted among three traditional segmentation methods and two deep learning *** results show that the AP-UNet segmentation model can effectively suppress complicated water column noise *** segmentation precision,the Dice coefficient,and the recall rate of this model are 92.09%,92.00%,and 92.49%,respectively,which are 1.17%,2.10%,and 2.07%higher than the results of the UNet.

关键词： multibeam water column image(WCI) gas plumes UNet automatic segmentation

Single crystal erbium compound nanowires as high gain material for on-chip light source applications

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Frontiers of Optoelectronics 2016年第2期9卷 312-317页

作者： Zhicheng LIU Hao SUN Leijun YIN Yongzhuo LI jianxing zhang Cun-Zheng NING School of Electrical Computer and Energy Engineering Arizona State University Tempe Arizona 85287 USA Department of Electronic Engineering Tsinghua University Beijing 100084 China

Integrated photonics requires high gain optical materials in the telecom wavelength range for optical amplifiers and coherent light sources. Erbium （Er） containing materials are ideal candidates due to the 1.5 μm emission from Era＋ ions. However, the Er density in typical Er-doped materials is less than 10^20 cm-3, thus limiting the maximum optical gain to a few dB/cm, too small to be useful for integrated photonic applications. Er compounds could potentially solve this problem since they contain much higher Era＋ density. So far the existing Er compounds suffer from short lifetime and strong upconversion effects, mainly due to poor crystal qualities. Recently, we explore a new Er compound： erbium chloride silicate （ECS, Er3（SiO4）2C1） in the form of nanowire, which facilitates the growth of high quality single crystal with relatively large Era＋ density 0.62 ×10^22 cm^-3）. Previous optical results show that the high crystal quality of ECS material leads to a long lifetime up to 1 ms. The Er lifetime-density product was found to be the largest among all the Er containing materials. Pump-probe experiments demonstrated a 644 dB/cm signal enhancement and 30 dB/cm net gain per unit length from a single ECS wire. As a result, such high-gain ECS nanowires can be potentially fabricated into ultra-compact lasers. Even though a single ECS nanowire naturally serves as good wavegnide, additional feedback mechanism is needed to form an ultra-compact laser. In this work, we demonstrate the direct fabrication of 1D photonic crystal （PhC） air hole array structure on a single ECS nanowire using focused ion beam （FIB）. Transmission measurement shows polarization-dependent stop-band behavior. For transverse electric （TE） polarization, we observed stop-band suppression as much as 12 dB with a 9 μm long airholed structure. Through numerical simulation, we showed that Ω-factor as high as 11000 can be achieved at 1.53 μm for a 1D PhC micro-cavity on an ECS nanowire. Such a high Q cavity co

关键词： nanomaterials rare-earth-doped materials,lasers optical amplifiers nanostructure fabrication micro-cavity devices

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秸秆醋酸纤维素的制备

化工学报 2007年第10期58卷 2548-2553页

作者：张建兴陈洪章中国科学院过程工程研究所生化工程国家重点实验室

农作物秸秆是自然界中数量极大的可再生资源,本研究以农作物秸秆为反应原料,采用无污染蒸汽爆破技术活化预处理,然后进行乙酰化反应,通过溶剂萃取分离并制备出高附加值的醋酸纤维素。实验结果表明:秸秆汽爆后明显增加了反应活性,制备醋... 详细信息

农作物秸秆是自然界中数量极大的可再生资源,本研究以农作物秸秆为反应原料,采用无污染蒸汽爆破技术活化预处理,然后进行乙酰化反应,通过溶剂萃取分离并制备出高附加值的醋酸纤维素。实验结果表明:秸秆汽爆后明显增加了反应活性,制备醋酸纤维素的适宜条件是123℃,2h,催化剂用量为7%;汽爆秸秆中性洗涤剂处理后的乙酰化结果效果最好;不同汽爆秸秆中小麦秸秆乙酰化效果最佳;优化实验条件下,秸秆醋酸纤维素聚合度均在120以上,取代度2.80以上;并且用红外图谱、1HNMR进行了表征。与目前工业上采用α-纤维素含量较高的高级浆为反应原料相比,不仅原料和预处理成本大大降低,而且工艺流程简单。

关键词：秸秆醋酸纤维素蒸汽爆破乙酰化

高流量鼻导管吸氧在妊娠合并心脏病患者剖宫产中的随机对照研究

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南方医科大学学报 2024年第6期44卷 1040-1047页

作者：胡家祺张建杏南方医科大学附属广东省人民医院//广东省医学科学院麻醉一科广东广州510080

目的探讨高流量鼻导管(HFNC)吸氧在妊娠合并心脏病患者剖宫产中的应用。方法本研究为单中心、单盲、随机临床试验。拟行剖宫产的妊娠合并心脏病患者被随机分为2组:HFNC组接受HFNC疗法(n=27,吸气流量30 L/min,氧浓度40%),传统吸氧(COT... 详细信息

目的探讨高流量鼻导管(HFNC)吸氧在妊娠合并心脏病患者剖宫产中的应用。方法本研究为单中心、单盲、随机临床试验。拟行剖宫产的妊娠合并心脏病患者被随机分为2组:HFNC组接受HFNC疗法(n=27,吸气流量30 L/min,氧浓度40%),传统吸氧(COT)组接受传统氧疗(n=31,通过鼻导管输送,氧流量5L/min)。主要观察指标为母体血氧饱和度下降(SpO20.05)。结论 HFNC疗法显著降低了妊娠合并心脏病患者围手术期母体血氧饱和度下降的发生率,并且对母体或胎儿的短期临床结果没有不良影响。

关键词：传统氧疗高流量鼻导管吸氧母体血氧饱和度下降术后白细胞增高妊娠合并心脏病

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Ultrafast pulse wave velocity technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis patients with euthyroidism

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中国医学影像技术 2024年第8期40卷 1179-1182页

作者： JIANG Yanhui LIU Meiling XIE Jingwen zhang jianxing Department of Ultrasound the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120China

Objective To explore the value of ultrafast pulse wave velocity(UFPWV)technique for evaluating changes of carotid artery elasticity in Hashimoto thyroiditis(HT)patients with *** Conventional ultrasound and UFPWV for carotid artery were prospectively performed in 91 HT patients with euthyroidism(HT group)and 81 healthy subjects(control group).Clinical data and ultrasonic parameters were compared between *** correlation analysis was performed to observe the correlations of carotid pulse wave velocity in end of systole(PWV-ES)with clinical indexes and other ultrasonic parameters in HT *** stepwise linear regression analysis was used to screen the independent impact factors of increased carotid PWV-ES in HT *** Significant differences of thyroid peroxidase antibody(TPOAb),thyroglobulin antibody(TgAb),total cholesterol(TC),low density lipoprotein and neutrophil-lymphocyte ratio(NLR)were found between groups(all P0.05).Carotid PWV-ES in HT group was positively correlated with patients'age,body mass index,TPOAb,TC,triglyceride,NLR and CIMT(r=0.217—0.707,all P<0.05).Patients'age,TPOAb and NLR were all independent impact factors of increased carotid PWV-ES in HT patients with euthyroidism(all P<0.05).Conclusion UFPWV technique could be used to evaluate changes of carotid artery elasticity in HT patients with euthyroidism,among which PWV-ES was relatively sensitive.

关键词： Hashimoto disease carotid arteries ultrasonography prospective studies

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基于影像重叠程度的初始接缝线网络生成方法

武汉大学学报（信息科学版） 2019年第10期44卷 1518-1523页

作者：张建兴杨柳忠于静张宁住房和城乡建设部遥感应用中心北京100835 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101

初始接缝线网络是影像镶嵌中的重要一环,特别是在遥感影像处理中,它的生成质量对后续接缝线的优化具有重要影响。设计了一种新颖的初始接缝网络线生成方法,它将影像有效区域的重叠拓扑以比特数组的形式进行了封装,并分别赋给了点、线、... 详细信息

初始接缝线网络是影像镶嵌中的重要一环,特别是在遥感影像处理中,它的生成质量对后续接缝线的优化具有重要影响。设计了一种新颖的初始接缝网络线生成方法,它将影像有效区域的重叠拓扑以比特数组的形式进行了封装,并分别赋给了点、线、面这些平面几何要素。一方面,这有助于挖掘影像重叠区之间的空间联系,便于计算接缝线连接的优先关系,使得接缝线的生成不再受制于重叠区域的具体形状,而仅考虑影像的重叠程度,从而大大提高了接缝生成的鲁棒性。另一方面,基于比特运算的高效性也使该方法在接缝线生产效率上体现出优势。与顾及重叠的面Voronoi图的方法进行了对比,该方法在接缝线生成的鲁棒性和效率上都具有一定优势。

关键词：接缝线镶嵌重叠程度位运算遥感