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Quantitative Inversion of REEs in Ion-Adsorbed Rare Earth Ores from the Liutang Area(South China),Based on Measured Hyperspectral Data

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Journal of Earth Science 2023年第4期34卷 1068-1082页

作者： gong Cheng hongrui Zhang Huan Li Xiaoqing Deng Safiyanu Muhammad Elatikpo Jiaxuan Li Zhenguang Hu Guangqiang Li Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China School of Mathematics and Statistics Hunan University of Technology and BusinessChangsha 410205China Chinalco Guangxi Nonferrous Rare Earth Development Co. Ltd.Nanning 532299China

Rare earth minerals are important strategic resources to economic development all over the *** this study,multiple linear regression and back propagation(BP) neural network methods are used to invert the contents of ion adsorbed rare earth elements(REEs) and exploring the feasibility of quantitative inversion of REEs through measured hyperspectral data in Liutang rare earth mines,South *** result shows that the spectral curve of the rare earth ore samples has obvious absorption characteristics around 390,930,1 400,1 900 and 2 200 nm,and continuum removal and the 1st derivative treatment can highlight the absorption *** modeling accuracies of BP neural network are higher than that of multiple linear regression *** BP neural network model of the 1st derivative data in 400–1 000 nm bands has the best inversion result of the total content of REEs,R2 reaches 0.98,the ratio of the performance to deviation(RPD) is larger than *** quantitative inversion model of each REE(except for Ce) has high precision,R2 is greater than 0.90 and RPD is greater than *** results indicate that quantitative inversion of REEs using measured spectra not only has great potential and feasibility in the exploration of rare earth minerals,but also provides a rapid test method for the content of ion-adsorbed rare earth elements.

关键词： hyperspectral ion-adsorbed ore neural network quantitative inversion rare earth ele-ments(REEs).

体外冲击波联合不同牵伸训练对脑卒中后小腿三头肌痉挛的疗效观察

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济宁医学院学报 2024年第2期47卷 117-122页

作者：朱保亮王强张洪蕊周人龙张强巩小雪青岛大学附属医院康复医学科青岛266000 济宁医学院附属医院康复科济宁272029

目的探讨体外冲击波(extracorporeal shock wave therapy,ESWT)联合不同牵伸训练治疗卒中后小腿三头肌痉挛的效果。方法选取2020年3月到2021年8月符合标准的患者60例作为研究对象,采用随机数字表法分为ESWT治疗组(对照组)、ESWT联合... 详细信息

目的探讨体外冲击波(extracorporeal shock wave therapy,ESWT)联合不同牵伸训练治疗卒中后小腿三头肌痉挛的效果。方法选取2020年3月到2021年8月符合标准的患者60例作为研究对象,采用随机数字表法分为ESWT治疗组(对照组)、ESWT联合斜板牵伸组(联合组A)及ESWT联合静态牵伸组(联合组B),每组各20例。所有患者均在治疗前、治疗2周后、治疗4周后分别采用改良Ashworth(MAS)、改良Tardieu(MTS)、简化Fugl-Meyer运动功能下肢部分(FMA-LE)、踝关节PROM评估患者肌张力和下肢运动功能改善情况。结果训练前,3组患者MAS、MTS、FMA-LE和踝关节PROM比较无差异性(P>0.05)。给予2周训练后,3组患者以上4个指标和训练前相比均有一定的改善,联合组A、B MAS、MTS、PROM优于对照组(P0.05);联合组B踝关节PROM比联合组A效果明显,余3个指标无明显差异性(P>0.05)。给予4周训练后,3组患者MAS、MTS、FMA-LE和踝关节PROM改善程度明显,且联合组A较对照组显著(P<0.05),联合组B较其他两组改善显著(P<0.05)。结论 ESWT联合静态牵伸训练对降低脑卒中后小腿三头肌痉挛,改善患者下肢运动功能有积极治疗作用,且效果优于联合斜板牵伸或单纯冲击波治疗,可作为治疗脑卒中后小腿三头肌痉挛的有效手段在临床推广、应用。

关键词：脑卒中小腿三头肌痉挛体外冲击波静态进展牵伸

R & D STRATEGIC INVESTMENT IN AN ASYMMETRICAL CASE

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Journal of Systems Science & Complexity 2006年第4期19卷 547-557页

作者： Minggao XUE Pu gong Department of Finance College of Management Huazhong University of Science and Technology Wuhan 430074 China.

This article analyzes R ＆ D investment decisions in an asymmetrical case. The investment decisions share three important characteristics. First, the investment is completely irreversible. Second, there are two kinds of uncertainties over the future returns from the investment and over technology in R ＆ D process, respectively. Third, there is strategic competition in the asymmetrical case. This article presents the optimal investment threshold values and the optimal investment rule of high-efficient firm （leader）, and shows that the investment threshold values are reduced by competition of two firms. Finally, the mixed investment strategies for two firms, the probability that each firm separately exercises the option to invest, and the probability that two firms simultaneously exercise the option are given in the paper.

关键词： Asymmetric information optimal investment threshold value option game preemption the mixed investment strategy.

In situ growth of 3D walnut-like nano-architecture Mo-Ni2P@NiFeLDH/NF arrays for synergistically enhanced overall water splitting

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Journal of Energy Chemistry 2020年第10期29卷 189-197页

作者： Zhi Yang Yu Lin Feixiang Jiao Jinhui Li Jinlei Wang Yaqiong gong Chemical Engineering and Technology North University of ChinaTaiyuan 030051ShanxiChina State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005FujianChina

The in situ growth of nano-array on material structure is a novel and high-efficient strategy to design catalysts,however,it still remains a challenge to fabricate unique nano-architecture electrocatalyst with prominent activity and superior durability for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).Herein,a unique nano-architecture catalyst is successfully synthesized by using NiFe LDH nanosheets as framework to the in situ growth Mo-doped Ni2 P ultrafine nanosheets(marked as Mo-Ni2 P@NiFe LDH/NF).The unique 3 D core-shell nano-architecture is favorable for enhancing electron transfer/mass diffusion,providing abundant active sites,prompting O2/H2 gas release,and creating the synergistic effect between Mo-Ni2 P and NiFe ***,comparing with pure NiFe LDH/NF and MoNi2 P/NF electrodes,walnut-like Mo-Ni2 P@Ni Fe LDH/NF catalyst exhibits significantly improved electrocatalytic activities and durability towards OER(269 m V@40 m A cm^-2),HER(82 mV@10 mA cm^-2),and overall water splitting(1.46 V@10 m A cm^-2),*** electrocatalytic activity of Mo-Ni2 P@NiFe LDH/NF is comparable with that of majority reported non-precious metal catalysts and even precious catalysts(IrO2 and Pt/C).This work presents a new perspective strategy to fabricate ingeniously bifunctional electrocatalysts with well-designed structure and superior performance for clean energy conversion technologies or storage devices.

关键词： Nano-architecture 3D walnut-like Synergistic effect In situ growth Bifunctional catalyst

Rational construction of Ag@MIL-88B(V)-derived hierarchical porous Ag-V_(2)O_(5) heterostructures with enhanced diffusion kinetics and cycling stability for aqueous zinc-ion batteries

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Journal of Energy Chemistry 2023年第2期77卷 561-571,I0015页

作者： Yibo Zhang Zhihua Li Liangjun gong Xuyu Wang Peng Hu Jun Liu School of Materials Science and Engineering Central South UniversityChangsha 410083HunanChina Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education Central South UniversityChangsha 410083HunanChina School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina Fine Chemical Industry Research Institute School of ChemistrySun Yat-Sen UniversityGuangzhou 510275GuangdongChina

With the advantages of the multiple oxidation states and highly open crystal structures,vanadium-based composites have been considered as the promising cathode materials for aqueous zinc-ion batteries(ZIBs).However,the inherent inferior electrical conductivity,low specific surface area,and sluggish Zn^(2+)diffusion kinetics of the traditional vanadium-based oxides have greatly impeded their ***,a novel hierarchical porous spindle-shaped Ag-V_(2)O_(5) with unique heterostructures was rationally designed via a simple MOF-assisted synthetic method and applied as stable cathode for aqueous *** high specific surface area and hierarchically porous superstructures endowed Ag-V_(2)O_(5) with sufficient electrochemical active sites and shortened the diffusion pathways of Zn^(2+),which was beneficial to accelerate the reversible transport of Zn^(2+)and deliver a high specific capacity(426 mA h g^(-1) at 0.1 A g^(-1) and 96.5%capacity retention after 100 cycles).Meanwhile,the self-built-in electric fields at the heterointerface of Ag-V_(2)O_(5) electrode could strengthen the synergistic coupling interaction between Ag and V_(2)O_(5),which can effectively enhance the electric conductivity and maintain the structural integrity,resulting in superb rate capability(326.1 mA h g^(-1) at 5.0 A g^(-1))and remarkable cycling stability(89.7%capacity retention after 2000 cycles at 5.0 A g^(-1)).Moreover,the reversible Zn^(2+)storage mechanism was further investigated and elucidated by kinetics analysis and DFT calculations.

关键词： Aqueous zinc-ion batteries Metal-organic frameworks V_(2)O_(5) Heterostructures Nano silver

基于BERT-SELFATT-CNN模型的垃圾邮件分类方法

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湖南文理学院学报（自然科学版） 2024年第2期36卷 14-18,70页

作者：龚红仿赵富荣罗容容长沙理工大学数学与统计学院湖南长沙410114

针对传统垃圾邮件分类方法中使用静态词向量不能解决一词多义、长序列信息特征提取不足等问题,提出了一种基于BERT-SELFATT-CNN模型的垃圾邮件分类方法。使用动态文本表示方法BERT对邮件内容进行预训练,并生成带有上下语义信息的词向量... 详细信息

针对传统垃圾邮件分类方法中使用静态词向量不能解决一词多义、长序列信息特征提取不足等问题,提出了一种基于BERT-SELFATT-CNN模型的垃圾邮件分类方法。使用动态文本表示方法BERT对邮件内容进行预训练,并生成带有上下语义信息的词向量,经过能够并行计算的自注意力机制层计算词与词之间的相似度去挖掘句子长距离信息,将生成的隐藏层向量输入到CNN网络提取向量局部特征。在中文垃圾邮件数据集上与已有模型进行对比实验,结果表明该模型在精确度、召回率和F1值上均有提高,模型训练速度也得到提升。

关键词：垃圾邮件 BERT 自注意力层 CNN 文本分类

Theory on the molecular characteristic contour (II)——Molecular intrinsic characteristic contours of several typical organic molecules

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Science China Chemistry 2005年第2期48卷 89-100页

作者： gong Lidong, ZHAO Dongxia & YANG Zhongzhi Department of Chemistry, Liaoning Normal University, Dalian 116029, China Correspondence should be addressed to Yang Zhongzhi (email: zzyang@***) Dept. of Chem. Liaoning Normal Univ. Dalian 116029 China

The molecular intrinsic characteristic contour (MICC) is defined based on the clas-sical turning point of electron movement in a molecule. Three typical organic molecules, i.e. methane, methanol and formic acid, were employed as examples for detailed introduction of our method. Investigations on the cross-sections of MICC provide important information about atomic size changing in the process of forming molecules. The electron density distributions on the MICCs of these molecules were calculated and shown for the first time. Results showed that the electron density distribution on the MICC correlates closely with molecular chemical properties, and it provides a new insight into molecular boundary.

关键词： molecular intrinsic characteristic contour (MICC) potential acting on an electron in a molecule electron density organic molecules ab initio method.

Microstructure optimization of core@shell structured MSe_(2)/FeSe_(2)@MoSe_(2)(M=Co,Ni)flower-like multicomponent nanocomposites towards high-efficiency microwave absorption

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Journal of Materials Science & Technology 2022年第33期128卷 59-70页

作者： Jingjing Zhang Xiaosi Qi Xiu gong Qiong Peng Yanli Chen Ren Xie Wei Zhong College of Physics Guizhou Province Key Laboratory for Photoelectrics Technology and ApplicationGuizhou UniversityGuiyang 550025China National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology Nanjing UniversityNanjing 210093China

In this work,we put forward a scheme to exquisitely design and selectively synthesize the core@shell structured MSe_(2)/FeSe_(2)@MoSe_(2)(M=Co,Ni)flower-like multicomponent nanocomposites(MCNCs)through a simple two-step hydrothermal reaction on the surfaces of MFe_(2)O_4 nanospheres with the certain amounts of Mo and Se *** increasing the amounts of Mo and Se sources,the obtained core@shell structured MSe_(2)/FeSe_(2)@MoSe_(2)(M=Co,Ni)MCNCs with the enhanced content of MoSe_(2)and improved flower-like geometry morphology could be produced on a large *** obtained results revealed that the as-prepared samples displayed improved comprehensive microwave absorption properties(CMAPs)with the increased amounts of Mo and Se *** as-prepared CoSe_(2)/FeSe_(2)@MoSe_(2)and NiSe_(2)/FeSe_(2)@MoSe_(2)MCNCs with the well-defined flower-like morphology could simultaneously present the outstanding CMAPs in terms of strong absorption capability,wide absorption bandwidth,and thin matching thicknesses,which mainly originated from the conduction loss and flower-like geometry ***,the findings not only develop the very desirable candidates for high-performance microwave absorption materials but also pave a new way for optimizing the CMAPs through tailoring morphology engineering.

关键词： Core@shell structure MSe_(2)/FeSe_(2)@MoSe_(2)(M=Co.Ni) multicomponent nanocomposites Flower-like geometry morphology Broad frequency bandwidth Microwave absorption

Tunable and improved microwave absorption of flower-like core@shell MFe_(2)O_(4)@MoS_(2)(M=Mn,Ni and Zn)nanocomposites by defect and interface engineering

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Journal of Materials Science & Technology 2023年第8期139卷 137-146页

作者： Junxiong Xiao Xiaosi Qi Xiu gong Qiong Peng Yanli Chen Ren Xie Wei Zhong College of Physics Guizhou Province Key Laboratory for Photoelectrics Technology and ApplicationGuizhou UniversityGuiyang 550025China National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology Nanjing UniversityNanjing 210093China

Previous results revealed that the defect and/or interface had a great impact on the electromagnetic pa-rameters of *** order to understand the main physical mechanisms and effectively utilize these strategies,in this study,M Fe_(2)O_(4)and flower-like core@shell M Fe_(2)O_(4)@MoS_(2)(M=Mn,Ni,and Zn)sam-ples with different categories were elaborately designed and selectively produced in large scale through a simple two-step hydrothermal *** conducted the systematical investigation on their microstruc-tures,electromagnetic parameters and microwave absorption performances(MAPs).The obtained results revealed that the large radius of M^(2+)cation could effectively boost the concentration of oxygen vacancy in the M Fe_(2)O_(4)and M Fe_(2)O_(4)@MoS_(2)samples,which resulted in the improvement of dielectric loss capabil-ities and ***,the introduction of MoS_(2)nanosheets greatly improved the interfacial effect and enhanced the polarization loss capabilities,which also boosted the *** taking full advantage of the defect and interface,the designed M Fe_(2)O_(4)@MoS_(2)samples displayed tunable and excellent com-prehensive MAPs including strong absorption capability,wide absorption bandwidth and thin matching ***,the clear understanding of defect and interface engineering made these strategies well elaborately designed and applicable to improving MAPs.

关键词： Core@shell structure M Fe_(2)O_(4)@MoS_(2)(M=Mn,Ni and Zn) Defect and interface engineering Improved microwave absorption properties