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Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields

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Chinese Journal of Polymer Science 2024年第7期42卷 958-967,I0008页

作者： Yun-Zhi huang xiao-xiao Liu Lan-Wei Li Guang-Ming huang Zhao-Xia huang Jin-Ping Qu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China School of Advanced Manufacturing Technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface

Overview of computation strategies on the dispersion analysis for explicit finite difference solution of acoustic wave equation

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Petroleum Science 2024年第4期21卷 2311-2328页

作者： Jian-Ping huang Wei-Ting Peng Ji-Dong Yang Lu-Feng lou School of Geosciences China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266000ShandongChin

Finite-difference(FD)method is the most extensively employed numerical modeling ***,when using the FD method to simulate the seismic wave propagation,the large spatial or temporal sampling interval can lead to dispersion errors and numerical *** the FD scheme,the key factor in determining both dispersion errors and stability is the selection of the FD ***,How to obtain appropriate FD weights to guarantee a stable numerical modeling process with minimum dispersion error is *** FD weights computation strategies can be classified into three types based on different computational ideologies,window function strategy,optimization strategy,and Taylor expansion *** this paper,we provide a comprehensive overview of these three strategies by presenting their fundamental *** conduct a set of comparative analyses of their strengths and weaknesses through various analysis tests and numerical *** to these comparisons,we provide two potential research directions of this field:Firstly,the development of a computational strategy for FD weights that enhances stability;Secondly,obtaining FD weights that exhibit a wide bandwidth while minimizing dispersion errors.

关键词： Finite-difference scheme FD coefficients Dispersion error Forward modeling Numerical simulation

Machine learning and numerical investigation on drag reduction of underwater serial multi-projectiles

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Defence Technology（防务技术） 2022年第2期18卷 229-237页

作者： Xi huang Cheng Cheng xiao-bing Zhang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China

To increase launching frequency and decrease drag force of underwater projectiles,a serial multiprojectiles structure based on the principle of supercavitation is proposed in this *** drag reduction and supercavitation characteristics of the underwater serial multi-projectiles are studied with computational fluid dynamics(CFD)and machine ***,the numerical simulation model for the underwater supercavitating projectile is established and verified by experimental *** the evolution of the supercavitation for the serial multi-projectiles is *** addition,the effects of different cavitation numbers and different distances between projectiles are investigated to demonstrate the supercavitation and drag reduction ***,the artificial neural network(ANN)model is established to predict the evolution of drag coefficient based on the data obtained by CFD,and the results predicted by ANN are in good agreement with the data obtained by *** finding provides a useful guidance for the research of drag reduction characteristics of underwater serial projectiles.

关键词： Drag reduction Serial multi-projectiles Machine learning Artificial neural network(ANN) Numerical simulation

Fabrication of rigid and flexible SrGe409 nanotube-based sensors for room-temperature ammonia detection

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Nano Research 2018年第1期11卷 431-439页

作者： Tingting huang Zheng lou Shuai Chen Rui Li Kai Jiang Guozhen Shen [1College of Physics and Mathematics and Beiing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science University of Science and Technology Beiing Beiing 100083 China [2State Key Laboratory for Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China [3Institute & Hospital of Hepatobiliary Surgery Key Laboratory of Digital Hepatobiliary Surgery of Chinese PLA Chinese PLA Medical School Chinese PLA General Hospital Beijing 100853 China [4College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100049 China

Ammonia （NH3） detection at room temperature has attracted considerable attention because of the increasing demand for health monitoring, personal safety protection, and industrial manufacturing. Herein, we report the synthesis of polycrystalline SrGe409 nanotubes （NTs） via an electrospinning process. These NTs are a new sensing material for the detection of ammonia at room temperature. The SrGe409 NTs exhibited a maximum sensing response of 2.49 for 100 ppm NH3, which was increased to 7.08 by decorating the NTs with Pt nanoparticles. Flexible gas sensors were fabricated, which exhibited comparable performance to the rigid device. Additionally, the flexible devices showed excellent flexibility, mechanical stability, and sensing stability under different bending states, manifesting their potential applications in flexible and wearable electronics.

关键词： gas sensors ammonia nanotubes flexible electronics

Effect of Rare Earth Sc Addition on Microstructure and Mechanical Properties of an Al-Cu-Mg-Ag Alloy

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稀有金属材料与工程 2009年第A3期38卷 78-82页

作者： xiao Daihong huang Boyun State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

Al-5.3Cu-0.8Mg-0.6Ag alloys containing 0, 0.1, 0.3 and 0.5 (mass. %) Sc were prepared by ingot metallurgy and thermomechanical treatment. The effect of Sc addition on the precipitation and microstructure of the alloys has been investigated using mechanical testing, optical microscope, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It has been shown that trace Sc element refines the grains of the casting alloys and the average grain size decreases from 85 μm to 30 μm. Increasing Sc content from 0.1 to 0.3% accelerates the aging hardening process, increases the maximum hardness and the tensile strength of the extruded alloys from room temperature to 300 ℃. The high strength of the alloys with Sc is attributed to the high density and high thermal stability of fine Ω precipitates, and nanosized Al3(Sc,Zr) and AlCu(Zr, Sc) particles.

关键词：合金微观结构电子显微镜拉伸强度

Two-dimensional synthetic templates

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National Science Review 2015年第1期2卷 19-21页

作者： xiao huang Hua Zhang Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM) Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM)Nanjing Tech University(Nanjing Tech) School of Materials Science and Engineering Nanyang Technological University

The isolation of atomic-thin graphene sheets from bulk graphite has led to the discovery of a number of novel properties of graphene that have enormously beneited the development of nanotechnology[1],which has inspired the exploration of other 2D materials,such as transition metal dichalcogenides(TMDs),hexagonal boron nitride(hBN),etc.[2].To exfoliate a layered bulk

关键词： Two-dimensional synthetic templates

Theoretical Studies on the Fe-M Interactions and 31p NMR in Fe（CO）3（EtPhPpy）2MX2 （X=NCS, SCN, CI; M=Zn, Cd, Hg）

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Chinese Journal of Chemical Physics 2008年第5期21卷 438-444页

作者： xiao-xuan huang Xuan Xu Mei-xiang Xie School of Chemistry and Environment Key Lab of Technology on Electrochemical Energy Storage and Power Generation in Guangdong Universities South China Normal University Guangzhou 510006 China

To study the Fe-M interactions and their effects on 31p NMR, the structures of Fe（CO）3（EtPhPpy）2 1, Fe（CO）3（EtPhPpy）2M（NCS）2 （2： M=Zn, 3： M=Cd, 4： M=Hg） and Fe（CO）3（EtPhPpy）2CdX2 （5： X=C1, 6： X=SCN） were investigated by density functional theory （DFT） PBE0 method. The stabilities S of complexes follow S（2）〉S（3）〉S（4） and S（3）,.~S（6）〉S（5）, indicating that 6 is stable and may be synthesized. The complexes with thiocyanate are more stable than that with chloride in Fe（CO）3（EtPhPpy）2CdX2. The strength I of Fe-M interactions follows I（2）≈I（3）〈I（4）. The Fe-Cd interactions of 3 and 6, which contain thiocyanate, are stronger than that of 5 with chloride. The charge-transfer, which enhances with the increasing of Fe-M interaction strength, comes from Et, Ph, py, CO groups towards P, Fe, and M atoms. Because the delocalization of thiocyanate disperses the charge of M2＋, the charge-transfer of the complexes with thiocyanate is stronger than that with chloride. There is a a-bond between Fe and Hg atoms in 4. However, in binuclear complexes except 4, the Fe-M interactions act as nFe→nM, σP-Fe→nM and σC-Fe→nM delocalization, and the N-M interactions mainly act as nN→nM delocalization. In binuclear complexes, due to the Fe→M interactions, the strong σFe--C→σ＊Fe--p or σFe-Hg→σ＊Fe--I2 delocalization and the charge-transfer, the electron density on P nucleus is increased, and thus upfield 31p chemical shifts are caused （compared with mononuclear complex 1）.

关键词： DFT 31p NMR Metal-metal interaction Nature bond orbital

Effects of lanthanum(Ⅲ) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation

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Journal of Environmental Sciences 2007年第11期19卷 1361-1366页

作者： CAO Rui huang xiao-hua ZHOU Qing CHENG xiao-ying The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi 214036 China College of Chemistry and Environment Science Nanjing Normal University Nanjing 210097 China

The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum （La） on nitrogen metabolism under two different levels of elevated UV-B radiation （UV-B, 280-320 nm）. The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m^2 and high level 0.45 W/m^2 significantly affected the whole nitrogen metabolism in soybean seedlings （p 〈 0.05）. It restricted uptake and transport of NO3^-, inhibited activity of some key nitrogen-metabolism-related enzymes, such as： nitrate reductase （NR） to the nitrate reduction, glutamine systhetase （GS） and glutamine synthase （GOGAT） to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase （GDH）, which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La （20 mg/L）, La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.

关键词： lanthanum(Ⅲ) UV-B radiation soybean seedlings nitrogen metabolism alleviating effect

Field-assisted machining of difficult-to-machine materials

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International Journal of Extreme Manufacturing 2024年第3期6卷 39-89页

作者： Jianguo Zhang Zhengding Zheng Kai huang Chuangting Lin Weiqi huang xiao Chen Junfeng xiao Jianfeng Xu State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China School of Mechanical Engineering Hubei University of TechnologyWuhan 430068People’s Republic of China

Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material ***,traditional machining technologies often struggle to achieve ultra-precision with DMMs resulting from poor surface quality and low processing *** recent years,field-assisted machining (FAM) technology has emerged as a new generation of machining technology based on innovative principles such as laser heating,tool vibration,magnetic magnetization,and plasma modification,providing a new solution for improving the machinability of *** technology not only addresses these limitations of traditional machining methods,but also has become a hot topic of research in the domain of ultra-precision machining of *** new methods and principles have been introduced and investigated one after another,yet few studies have presented a comprehensive analysis and *** fill this gap and understand the development trend of FAM,this study provides an important overview of FAM,covering different assisted machining methods,application effects,mechanism analysis,and equipment *** current deficiencies and future challenges of FAM are summarized to lay the foundation for the further development of multi-field hybrid assisted and intelligent FAM technologies.

关键词： field-assisted machining difficult-to-machine materials materials removal mechanism surface integrity