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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang he Lingzi Shi Ran Sun Lianfei Ding Mukun he Jiaming Li Hua Guo Tiande Gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption

无铵助镀剂热浸Zn-0.05% Al合金浴的镀层性能研究

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热加工工艺 2015年第4期44卷 181-183,190页

作者：谭杰何明奕赵晓军王胜民昆明理工大学材料保护研究所云南昆明650093

用SEM、EDS、电化学和全浸试验检等方法对比分析了传统氯化锌铵助镀剂和无铵助镀剂两种助镀工艺对镀层性能的影响,以探讨无铵助镀工艺对镀层性能的影响及其作用机理。结果表明;在无铵助镀条件下,镀层厚度与传统助镀条件的相差不大,但得... 详细信息

用SEM、EDS、电化学和全浸试验检等方法对比分析了传统氯化锌铵助镀剂和无铵助镀剂两种助镀工艺对镀层性能的影响,以探讨无铵助镀工艺对镀层性能的影响及其作用机理。结果表明;在无铵助镀条件下,镀层厚度与传统助镀条件的相差不大,但得到的合金层组织更为致密,各相层间无明显分界线和裂纹,在一定程度上抑制了脆性相ζ层的生长,有利于塑性相δ层的生长;在提高镀层的黏附性的同时也提高了镀层的耐腐蚀性,其耐腐蚀性能较传统氯化锌铵助镀提高1倍左右。

关键词：热浸镀锌无铵助镀耐腐蚀性能电化学

Multifunctional Nacre‑Like Nanocomposite Papers for Electromagnetic Interference Shielding via heterocyclic Aramid/MXene Template‑Assisted In‑Situ Polypyrrole Assembly

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Nano-Micro Letters 2025年第3期17卷 37-54页

作者： Jinhua Xiong Xu Zhao Zonglin Liu he Chen Qian Yan Huanxin Lian Yunxiang Chen Qingyu Peng Xiaodong he National Key Laboratory of Science and Technology On Advanced Composites in Special Environments Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150080People’s Republic of China

Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication, and portable/wearable electronic *** this work, a nacre-inspired multifunctional heterocyclic aramid(HA)/MXene@polypyrrole (PPy) (HMP) nanocomposite paper withlarge-scale, high strength, super toughness, and excellent tolerance tocomplex conditions is fabricated through the strategy of HA/MXenehydrogel template-assisted in-situ assembly of PPy. Benefiting from the"brick-and-mortar" layered structure and the strong hydrogen-bondinginteractions among MXene, HA, and PPy, the paper exhibits remarkable mechanical performances, including high tensile strength (309.7 MPa),outstanding toughness (57.6 MJ m−3), exceptional foldability, and structural stability against ultrasonication. By using the template effect ofHA/MXene to guide the assembly of conductive polymers, the synthesized paper obtains excellent electronic conductivity. More importantly,the highly continuous conductive path enables the nanocomposite paper to achieve a splendid EMI shielding effectiveness (EMI SE) of 54.1 dBat an ultra-thin thickness (25.4 μm) and a high specific EMI SE of 17,204.7 dB cm2g−1. In addition, the papers also have excellent applicationsin electromagnetic protection, electro-/photothermal de-icing, thermal therapy, and fire safety. These findings broaden the ideas for developinghigh-performance and multifunctional MXene-based films with enormous application potential in EMI shielding and thermal management.

关键词： MXene Remarkable mechanical properties heterocyclic aramid Electromagnetic interference shielding Polypyrrole Multifunctionality

Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan Hou Xiaofei Qi Kan he College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin LI Yibo ZHOU Tao ZHAO Xingjian he Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

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热镀锌层钛盐钝化膜耐蚀性能的研究

热加工工艺 2011年第18期40卷 138-140页

作者：刘洪锋何明奕王胜民赵晓军昆明理工大学材料保护研究所云南昆明650093

以钛盐为主盐,加入双氧水、硝酸(磷酸)、络合剂等配制无铬钝化液,经钝化后在镀锌层表面获得一层均匀的无铬钝化膜。通过电化学试验、盐雾腐蚀试验、大气暴露试验等测试手段对比研究了铬酸盐钝化膜、钛盐钝化膜、镀锌层的耐蚀性能以及影... 详细信息

以钛盐为主盐,加入双氧水、硝酸(磷酸)、络合剂等配制无铬钝化液,经钝化后在镀锌层表面获得一层均匀的无铬钝化膜。通过电化学试验、盐雾腐蚀试验、大气暴露试验等测试手段对比研究了铬酸盐钝化膜、钛盐钝化膜、镀锌层的耐蚀性能以及影响钝化膜耐蚀性的因素。结果表明:镀锌层经钛盐钝化后耐蚀性能明显改善,在中性盐雾箱内可以通过48 h连续喷雾而不产生白锈。

关键词：钛盐钝化耐蚀性

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基于小波能量加权的医学图像融合新算法

科学技术与工程 2006年第13期6卷 1949-1954页

作者：何凯何明一吴晓荣高涛陕西省信息获取与处理重点实验室西北工业大学电子信息学院西安710072

目前的大多数基于小波变换的医学图像融合算法,由于没有细致考虑低频分量融合规则以及高频分量邻域特征对于融合效果的重要性,因而得到的融合效果有时并不理想。现提出一种小波域按邻域加窗能量加权的融合准则,该准则根据人体颅部18FFDG... 详细信息

目前的大多数基于小波变换的医学图像融合算法,由于没有细致考虑低频分量融合规则以及高频分量邻域特征对于融合效果的重要性,因而得到的融合效果有时并不理想。现提出一种小波域按邻域加窗能量加权的融合准则,该准则根据人体颅部18FFDG和MRIT1图像的特点,充分考虑到了低频分量和高频分量邻域特征,对原图像高、低频小波系数分别选用具有不同物理意义的窗矩阵进行邻域加窗能量计算,以归一化加窗能量为权值对各小波系数进行加权,得到融合小波系数,经过小波反变换重构出融合图像。实验证明,采用提出的融合算法得到的融合图像很好地包含了源图像的信息,该算法在医学图像融合应用中比传统的小波系数取大算法、加权平均算法及按邻域方差加权算法效果更好。

关键词：医学图像融合 18F-FDG MRI-T1 小波变换高、低频窗函数 LHLE算法

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高光谱遥感数据特征挖掘技术研究进展

航天返回与遥感 2013年第1期34卷 1-12页

作者：何明一畅文娟梅少辉西北工业大学电子信息学院及对地观测研究中心陕西省信息获取与处理重点实验室西安710129

从目标空间尺度和传感器空间分辨率的相对大小,把高光谱遥感图像目标检测、识别与分类中的特征挖掘问题划分为多像元、单像元和亚像元3个层次,因而更具自然特性也更适合特征挖掘和目标分类与识别技术的分析。把高光谱遥感图像特征挖掘... 详细信息

从目标空间尺度和传感器空间分辨率的相对大小,把高光谱遥感图像目标检测、识别与分类中的特征挖掘问题划分为多像元、单像元和亚像元3个层次,因而更具自然特性也更适合特征挖掘和目标分类与识别技术的分析。把高光谱遥感图像特征挖掘方法归纳为以保留波段物理意义为主要目的的特征选择、以综合利用所有观测数据信息为主要特色的特征提取,和考虑亚像元多目标混合信息的特征混合3大类。重点且简明地从高光谱遥感数据光谱曲线与光谱特征、特征提取、特征选择以及特征混合分析几个方面综述高光谱遥感数据/图像的特征挖掘技术的研究进展并通过热点问题展望其未来的发展趋势。

关键词：高光谱图像处理特征挖掘特征选择特征提取特征混合遥感技术

Joint Estimation of SOH and RUL for Lithium-Ion Batteries Based on Improved Twin Support Vector Machineh

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Energy Engineering 2025年第1期122卷 243-264页

作者： Liyao Yang HongyanMa Yingda Zhang Wei he School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China Institute of Distributed Energy Storage Safety Big Data Beijing100044China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing100044China

Accurately estimating the State of health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management ***,due to the complex internal chemical systems of LIBs and the nonlinear degradation of their performance,direct measurement of SOH and RUL is *** address these issues,the Twin Support Vector Machine(TWSVM)method is proposed to predict SOH and ***,the constant current charging time of the lithium battery is extracted as a health indicator(HI),decomposed using Variational Modal Decomposition(VMD),and feature correlations are computed using Importance of Random Forest Features(RF)to maximize the extraction of critical factors influencing battery performance ***,to enhance the global search capability of the Convolution Optimization Algorithm(COA),improvements are made using Good Point Set theory and the Differential Evolution *** Improved Convolution Optimization Algorithm(ICOA)is employed to optimize TWSVM parameters for constructing SOH and RUL prediction ***,the proposed models are validated using NASA and CALCE lithium-ion battery *** results demonstrate that the proposed models achieve an RMSE not exceeding 0.007 and an MAPE not exceeding 0.0082 for SOH and RUL prediction,with a relative error in RUL prediction within the range of[-1.8%,2%].Compared to other models,the proposed model not only exhibits superior fitting capability but also demonstrates robust performance.

关键词： State of health remaining useful life variational modal decomposition random forest twin support vector machine convolutional optimization algorithm

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镍铁锰三元前驱体材料的制备及性能研究

安徽理工大学学报（自然科学版） 2023年第5期43卷 68-75页

作者：刘少敏何明益汪子涵安徽理工大学地球与环境学院安徽淮南232001

镍铁锰三元材料是钠离子电池正极材料研究的热点之一,常采用固相法合成。然而,原料的混合均匀性差,难以控制形貌和晶粒大小,使得材料的电化学性能较差。为获得粒径小,形貌均一可控的正极材料,采用两步水热法先以硫酸镍、硫酸铁、硫酸锰... 详细信息

镍铁锰三元材料是钠离子电池正极材料研究的热点之一,常采用固相法合成。然而,原料的混合均匀性差,难以控制形貌和晶粒大小,使得材料的电化学性能较差。为获得粒径小,形貌均一可控的正极材料,采用两步水热法先以硫酸镍、硫酸铁、硫酸锰和氢氧化钠为原料合成镍铁锰三元前驱体材料Ni_(0.7)Fe_(0.2)Mn_(0.1)(OH)_(2),再将制备的前驱体混钠烧结制备三元材料。利用X衍射分析仪、扫描电子显微镜、X射线能谱仪和新威电池测试系统对其晶体结构、形貌、化学组成和电化学性能进行表征。重点研究了不同反应温度和时间对前驱体晶粒生长的影响,以及不同表面活性剂对前驱体形貌和结晶度的影响。结果表明,在170℃下保温12h,表面活性剂为10%添加量的聚乙二醇条件下合成的前驱体材料形貌光滑、组分均匀且一致性较好。首次充放电容量分别为128.79mAh/g和109.09mAh/g,具有84.7%的库伦效率。

关键词：镍铁锰三元前驱体水热法正极材料电化学性能