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Rare Metals 2015年第6期34卷 395-399页

作者： Sheng-Chu Li shui-jiang hu Ning Du Jia-Neng Fan Li-Jun Xu Jun Xu Shaoxing Test Institute of Quality and Technical Supervision State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering Zhejiang University

A novel and simple chemical reaction method was developed to synthesize dendrite-like La（OH）3 nanostructures which was composed of centripetal arranged La（OH）3 nanorods with diameters of 50-100 nm and lengths of several micrometers. The effect of different alkaline sources on the morphology of La（OH）3 nanostructures was investigated. It is indicated that diethyl- enetriamine acts not only as an alkaline source, but also as a surfactant which induces the centripetal growth of La（OH）3 nanostructures. Moreover, dendrite-like La203 nanostructures were prepared by the calcination of La（OH）3 nanostructures at 750 ℃. The morphology, structure, and composition of the as-synthesized products were characterized by transmission electron microscopy （SEM）, high-resolution transmission electron microscopy, field emission scanning electron microscopy （FESEM）, and X-ray powder diffraction （XRD）.

关键词： Crystal growth Nanomaterials Kinetics

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu jiang Ma Lina hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

High Strength and Stable Proton Exchange Membrane Based on Perfluorosulfonic Acid/Polybenzimidazole

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Chinese Journal of Polymer Science 2022年第7期40卷 764-771页

作者： Tang-Cheng Xu Chang-shui Wang Zhao-Yu hu Jiao-Jiao Zheng Shao-hua jiang shui-Jian He Hao-Qing Hou College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang330022China Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing210037China

In this work,a series of high strength,thermal stable and antioxidant proton exchange membranes were designed with solution processible polybenzimidazole(PBI)as the matrix and perfluorosulfonic acid(PFSA)as the fortifier for proton *** processible PBI was successfully synthesized by introducing 4,4’-dicarboxydiphenyl ether into the molecular chains of ***/PBI composite membranes were obtained by solution blending and film *** and PFSA/PBI composite membranes exhibited greatly enhanced tensile strength and Young’s modulus compared to ***/PBI composite membranes are stable below 300℃ which are suitable for practical application in proton exchange membrane fuel *** PFSA/PBI composite membranes show good dimensional stability with low water uptake and swelling *** PFSA/PBI composite membranes also exhibit excellent antioxidation stability with less than 5%initial mass loss over 120 h in Fenton *** proton conductivity of PBI is greatly enhanced by blending with PFSA and the proton conductivities of the composite membranes are increased with the raise of PFSA content and *** work offers valuable insights into the exploration of PBI based high-performance proton exchange membranes.

关键词： Solution processible polybenzimidazole Perfluorosulfonic acid Proton exchange membrane Film casting High strength

Probabilistic back-analysis of rainfall-induced landslides for slope reliability prediction with multi-source information

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3575-3594页

作者： shui-hua jiang Hong-hu Jie Jiawei Xie Jinsong huang Chuang-Bing Zhou School of Infrastructure Engineering Nanchang UniversityXuefu Road 999Nanchang330031China Discipline of Civil Surveying and Environmental EngineeringFaculty of Engineering and Built EnvironmentThe University of NewcastleCallaghanNSW2308Australia

Probabilistic back-analysis is an important means to infer the statistics of uncertain soil parameters,making the slope reliability assessment closer to the engineering ***,multi-source information(including test data,monitored data,field observation and slope survival records)is rarely used in current probabilistic *** the probabilistic back-analysis of spatially varying soil parameters and slope reliability prediction under rainfalls by integrating multi-source information is a challenging task since thousands of random variables and high-dimensional likelihood function are usually *** this paper,a framework by integrating a modified Bayesian Updating with Subset simulation(mBUS)method with adaptive Conditional Sampling(aCS)algorithm is established for the probabilistic back-analysis of spatially varying soil parameters and slope reliability *** this framework,the high-dimensional probabilistic back-analysis problem can be easily tackled,and the multi-source information(*** pressure heads and slope survival records)can be fully used in the back-analysis.A real Taoyuan landslide case in Taiwan,China is investigated to illustrate the effectiveness and performance of the established *** findings show that the posterior knowledge of soil parameters obtained from the established framework is in good agreement with the field ***,the updated knowledge of soil parameters can be utilized to reliably predict the occurrence probability of a landslide caused by the heavy rainfall event on September 12,2004 or forecast the potential landslides under future rainfalls in the Fuhsing District of Taoyuan City,Taiwan,China.

关键词： Rainfall-induced landslide Spatial variability Probabilistic back-analysis Slope reliability analysis Bayesian updating

Precision spectroscopy of atomic helium

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National Science Review 2020年第12期7卷 1818-1827页

作者： Yu R.Sun shui-Ming hu Hefei National Laboratory for Physical Sciences at Microscale iChem CenterUniversity of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China

Helium is a prototype three-body system and has long been a model system for developing quantum mechanics theory and computational *** fine-structure splitting in the 2;P state of helium is considered to be the most suitable for determining the fine-structure constant α in *** more than 50 years of efforts by many theorists and experimentalists,we are now working toward a determination ofα with an accuracy of a few parts per billion,which can be compared to the results obtained by entirely different methods to verify the self-consistency of quantum ***,the precision spectroscopy of helium allows determination of the nuclear charge radius,and it is expected to help resolve the ’proton radius puzzle’.In this review,we introduce the latest developments in the precision spectroscopy of the helium atom,especially the discrepancies among theoretical and experimental results,and give an outlook on future progress.

关键词： precision spectroscopy helium quantum electrodynamics fine-structure constant nuclear charge radius

Precise Asymptotics for Lévy Processes

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1265-1270页

作者： Zhi shui hu Chun SU Department of Statistics and Finance University of Science and Technology of China

Let {X（t）, t ≥ 0} be a Lévy process with EX（1） = 0 and EX^2（1）〈 ∞. In this paper, we shall give two precise asymptotic theorems for {X（t）, t 〉 0}. By the way, we prove the corresponding conclusions for s... 详细信息

关键词： precise asymptotic Lévy process stable process Fuk-Nagaev type inequality

Influence of rolling temperature on the interfaces and mechanical performance of graphene-reinforced aluminum-matrix composites

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 752-759页

作者： Chen-yang huang shui-ping hu Kai Chen Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

To study the influence of rolling on the interfaces and mechanical performance of graphene-reinforced Al-matrix composites,a rolling method was used to process *** scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy,and tensile testing,this study analyzed the micromorphology,interfaces,and mechanical performance of the composites before and after *** experimental results demonstrates that the composites after hot rolling has uniform structures with strong interfacial *** an increase in rolling temperature,the tensile strength and elastic modulus of the composites gradually ***,when the rolling temperature is higher than 500°C,granular and rod-like Al4C3 phases are observed at the interfaces and the mechanical performance of the composites is *** the rolling temperature is 480°C,the composites show the optimal comprehensive mechanical performance,with a tensile strength and elastic modulus of 403.3 MPa and 77.6 GPa,respectively,which represent increases of 31.6%and 36.9%,respectively,compared with the corresponding values prior to rolling.

关键词： rolling graphene composite interface mechanical performance

Strong invariance principle for a counterbalanced random walk

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 370-380页

作者： TAN hui-qun hu Zhi-shui DONG Liang International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China Center for Basic Teaching and Experiment Nanjing University of Science and TechnologyJiangyin 214443China

We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as *** n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n).

关键词： random walk martingale invariance principle

Novel estradiol sensors based on carbon nanotube multilayer modified gold hair microelectrodes

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Chinese Chemical Letters 2009年第10期20卷 1248-1250页

作者： Jun hui Xu Cheng Guo hu Sheng shui hu Department of Chemistry Wuhan University Wuhan 430072 China State Key Laboratory of Transducer Technology Chinese Academy of Sciences Beijing 100080 China

Multi-walled carbon nanotube multilayers were modified onto a newly proposed gold hair microelectrode via a simple layer-bylayer assembling method. The resulting electrode showed a sensitive oxidation response to estradiol with detection limit as low as 1.0 × 10^-8 mol/L, foreseeing a promising approach to the fabrication of high-sensitive microsensors.

关键词： Layer-by-layer assembly Carbon nanotubes Hair microsensors Estradiol

Predominating stable adsorption and direct electrochemistry of glucose oxidase on carbon nanotubes by oxygen-containing groups

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Chinese Chemical Letters 2007年第3期18卷 313-315页

作者： Chun Hai Yang Cheng Guo hu Sheng shui hu Departraent of Chemistry Wuhan University Wuhan 430072 China Key Laboratory of Biological Resources Protection and Utilization of hubei Province Enshi 445000 China

Stable adsorption and direct electrochemistry of glucose oxidase （COx） occurred on nitric acid （HNO3）-treated multi-walled carbon nanotubcs （MWNTs） instead of as-received MWNTs, demonstrating the critical roles ... 详细信息

关键词： Glucose oxidase Adsorption Direct electrochemistry Carbon nanotubes Oxygen-containing groups