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Numerical Mathematics(Theory,Methods and Applications) 2023年第1期16卷 242-276页

作者： Xiaopeng Zhu Zhizhang Wu Zhongyi huang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Department of Mathematics The University of Hong KongPokfulam RoadHong Kong SARChina

In this paper,we generalize the direct method of lines for linear elasticity problems of composite materials in star-shaped domains and consider its application to inverse elasticity *** assume that the boundary of the star-shaped domain can be described by an explicit C 1 parametric curve in the polar *** introduce the curvilinear coordinate,in which the irregular star-shaped domain is converted to a regular semi-infinite *** equations of linear elasticity are discretized with respect to the angular variable and we solve the resulting semidiscrete approximation analytically using a direct *** eigenvalues of the semi-discrete approximation converge quickly to the true eigenvalues of the elliptic operator,which helps capture the singularities ***,an optimal error estimate of our method is *** the inverse elasticity problems,we determine the Lam´e coefficients from measurement data by minimizing a regularized energy *** apply the direct method of lines as the forward solver in order to cope with the irregularity of the domain and possible singularities in the forward *** numerical examples are presented to show the effectiveness and accuracy of our method for both forward and inverse elasticity problems of composite materials.

关键词： Composite materials linear elasticity problems inverse elasticity problems starshaped domains method of lines

Implication of the South China Sea Throughflow for the Interannual Variability of the Regional Upper-Ocean Heat Content

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Advances in Atmospheric Sciences 2012年第1期29卷 54-62页

作者： LIU Qinyan Ruixin huang WANG Dongxiao State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301 Deptartment of Physical Oceanography Woods Hole Oceanographic InstitutionWoods HoleMassachusetts 02543USA

In this study the interannual variability of the upper-ocean heat content in the South China Sea （SCS） was revisited using simple ocean data assimilation （SODA） combined with objective analyzed data sets that included the horizontal and vertical structures. The results confirmed that the upper-ocean heat content in the SCS is lower than normal during the mature phase of E1 Nifio events, and two super E1 Nifio events, 1982/1983 and 1997/1998 were also included. The variability of the heat content was consistent with the variability of the dynamic height anomalies. The SCS throughflow （SCSTF） plays an important role in regulating the interannual variability of the heat content, especially during the mature phase of E1 Nifio events.

关键词： heat content South China Sea throughflow

Intermolecular Acid-Base-Pairs Containing Poly(p-Terphenyl-co-lsatin Piperidinium)for High Temperature Proton Exchange Membrane Fuel Cells

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Energy & Environmental Materials 2024年第3期7卷 406-414页

作者： Xiaofeng Hao Zhen Li Min Xiao Zhiheng huang Dongmei Han Sheng huang Wei Liu Shuanjin Wang Yuezhong Meng The Key Laboratory of Low-carbon Chemistry&Energy Conservation of Guangdong Province State Key Laboratory of Optoelectronic Materials and TechnologiesSchool of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519000China Institute of Chemistry Henan Provincial Academy of SciencesZhengzhou 450000China Research Center of Green Catalysts College of ChemistryZhengzhou UniversityZhengzhou 450001China

How to optimize and regulate the distribution of phosphoric acid in matrix,and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane(HT-PEMs)fuel cell are significant ***,bifunctional poly(p-terphenyl-co-isatin piperidinium)copolymer with tethered phosphonic acid(t-PA)and intrinsic tertiary amine base groups are firstly prepared and investigated as *** distinctive architecture of the copolymer provides a well-designed platform for rapid proton *** not only transports through the hydrogen bond network formed by the adsorbed free phosphoric acid(f-PA)anchored by the tertiary amine base groups,but also rely upon the proton channel constructed by the ionic cluster formed by the t-PA *** the design of the structure,the bifunctional copolymers with lower PA uptake level(<100%)display prominent proton conductivities and peak power densities(99 mS cm^(-1),812 mW cm^(-2)at 160℃),along with lower PA leaching and higher voltage stability,which is a top leading result in disclosed *** results demonstrate that the design of intermolecular acid-base-pairs can improve the proton conductivity without sacrificing the intrinsic chemical stability or mechanical property of the thin membrane,realizing win-win demands between the mechanical robustness and electrochemical properties of HT-PEMs.

关键词： bifunctional copolymer high temperature proton exchange membrane intermolecular acid-base-pairs phosphonic acid retention phosphonic acid uptake level

Simulation of epitaxial growth on convex substrate using phase field crystal method

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Frontiers of Materials Science 2014年第2期8卷 185-192页

作者： Ying-Jun GAO Li-Lin huang Qian-Qian DENG Kui LIN Chuang-Gao huang College of Physical Science and Engineering Guangxi University Nanning 530004 China Ministry Key Laboratory for Non-Ferrous Metal and Featured Materials Nanning 530004 China

Phase field crystal （PFC） model is employed to simulate the process of growth of epitaxial layer on plane-convex substrate with a lattice mismatch and a small inclination angle. The variation of the systematic free energy, the total atomic number of the epitaxial layer, and the effect of the curvature and the angle of the substrate are analyzed. The results show that when the surface of the substrate is plane, the free energy increases with the increase of the substrate inclination angle, and also the total atomic number of the epitaxial layer increases; while the surface of the substrate is convex, the free energy decreases with the increase of substrate angle and so also the total atomic number of the epitaxial layer decrease. This is the reason that the frontier of surface of epitaxial layer changes from the step bunching to the hill-and-valley facet structure with the increasing of the inclination angle of convex substrate. These results are in good agreement with the other method results.

关键词： heteroepitaxy phase field crystal (PFC) convex substrate atomic number

The oxygen cycle and a habitable Earth

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Science China Earth Sciences 2021年第4期64卷 511-528页

作者： Jianping huang Xiaoyue LIU Yongsheng HE Shuzhong SHEN zengqian HOU Shuguang LI Changyu LI Lijie YAO Jiping huang Collaborative Innovation Center for Western Ecological Safety College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences.Beijing 100101China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China LPS Nanjing Institute of Geology and Paleontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China National Science Foundation of China Beijing 100085China

As an important contributor to the habitability of our planet, the oxygen cycle is interconnected with the emergence and evolution of complex life and is also the basis to establish Earth system science. Investigating the global oxygen cycle provides valuable information on the evolution of the Earth system, the habitability of our planet in the geologic past, and the future of human life. Numerous investigations have expanded our knowledge of the oxygen cycle in the fields of geology,geochemistry, geobiology, and atmospheric science. However, these studies were conducted separately, which has led to onesided understandings of this critical scientific issue and an incomplete synthesis of the interactions between the different spheres of the Earth system. This review presents a five-sphere coupled model of the Earth system and clarifies the core position of the oxygen cycle in Earth system science. Based on previous research, this review comprehensively summarizes the evolution of the oxygen cycle in geological time, with a special focus on the Great Oxidation Event(GOE) and the mass extinctions, as well as the possible connections between the oxygen content and biological evolution. The possible links between the oxygen cycle and biodiversity in geologic history have profound implications for exploring the habitability of Earth in history and guiding the future of humanity. Since the Anthropocene, anthropogenic activities have gradually steered the Earth system away from its established trajectory and had a powerful impact on the oxygen cycle. The human-induced disturbance of the global oxygen cycle, if not controlled, could greatly reduce the habitability of our planet.

关键词： Oxygen cycle Habitable earth Mass extinction Anthropocene

Synthesis,formation mechanism,and intrinsic physical properties of several As/P-containing MAX phases

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Journal of Materials Science & Technology 2023年第2期133卷 23-31页

作者： Hongxiang Chen Sheng Li Jun Deng Zhilong Zhang Jianeng huang Fa Chang Li huang Shixuan Du Pinqiang Dai School of Materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Institute of Physics&University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fuzhou 350118China Center for Advanced Energy and Functional Materials Fujian University of TechnologyFuzhou 350118China Songshan Lake Materials Laboratory Dongguan 523808China CAS Key Laboratory of Vacuum Physics Beijing 100049China

321 phases are an atypical series of MAX phases,in which A=As/P,with superior elastic properties,fea-turing in the MA-triangular-prism bilayers in the crystal *** now,besides Nb 3 As 2 C,the pure phases of the other 321 compounds have not been realized,hampering the study of their intrinsic ***,molten-salt sintering(MSS)and solid-state synthesis(SSS)were applied to synthesize As/P-containing 321 phases and 211 *** the phase composition of the end-product via multiple-phase Rietveld refinement,we found that MSS can effectively improve the purity of P-containing MAX phases,with the phase content up to 99%in Nb_(3)P_(2)C and 75.4(5)%in Nb 2 *** contrast,MSS performed poorly on As-containing MAX phases,only 8.9(4)%for Nb 3 As 2 C and 64(2)%for Nb 2 AsC,as opposed to the pure phases obtained by *** experimental analyses combined with first-principles calculations reveal that the dominant formation route of Nb_(3)P_(2)C is through NbP+Nb+C→Nb_(3)P_(2)***,we found that the benefits of MSS on P-containing MAX phases are on the facilitation of three consid-ered chemical reaction routes,especially on Nb 2 PC+NbP→Nb_(3)P_(2)***,the intrinsic physical properties and Fermi surface topology of two 321 phases consisting of electron,hole,and open orbits are revealed theoretically and experimentally,in which the electron carriers are dominant in electrical *** feasible synthesis methods and the formation mechanism are instructive to obtain high-purity As/P-containing MAX phases and explore new MAX ***,the intrinsic physical properties will give great support for future applications on 321 phases.

关键词： MAX phase Molten-salt synthesis Chemical reaction route Metallic ceramics Formation mechanism Quasi-harmonic approximation

DNA alkylation promoted by an electron-rich quinone methide intermediate

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 213-221页

作者： Chengyun huang Steven E. Rokita Department of Chemistry and Biochemistry University of Maryland College Park MD 20742 USA Sichuan Institute of Geological Engineering Investigation Chengdu 610072 China Department of Chemistry Johns Hopkins University Baltimore MD 21218 USA

Biological application of conjugates derived from oligonucleotides and quinone methides have pre- viously been limited by the slow exchange of their covalent self-adducts and subsequent alkylation of target nucleic acids. To enhance the rates of these processes, a new quinone methide precursor with an electron donating substituent has been prepared. Additionally, this substi- tuent has been placed para to the nascent exo-methylene group of the quinone methide for maximum effect. A conjugate made from this precursor and a 5＇-aminohex- yloligonucleotide accelerates formation of its reversible self-adduct and alkylation of its complementary DNA as predicted from prior model studies.

关键词： quione methide DNA alkylation reversible covalent reaction bioconjugation target-directed modification of nucleic acids

高性能驱动系统在复杂工况下下运带式输送机的实现

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煤矿机械 2025年第1期46卷 161-164页

作者：黄洪华李军闫明道齐(上海)传动机械有限公司上海201613

下运带式输送机在复杂工况下需要具备稳定的运行性能和承载能力,能够适应各种突发情况并确保安全可靠的输送作业。对下运带式输送机上可控启动传输装置(CST)的应用进行了深入研究,通过项目验证高性能驱动系统的稳定性和可靠性,降低了能... 详细信息

下运带式输送机在复杂工况下需要具备稳定的运行性能和承载能力,能够适应各种突发情况并确保安全可靠的输送作业。对下运带式输送机上可控启动传输装置(CST)的应用进行了深入研究,通过项目验证高性能驱动系统的稳定性和可靠性,降低了能耗,为相关领域的研究提供了重要的理论和实践参考。

关键词：带式输送机 CST 异步电动机回馈制动

The singularity in the state-based peridynamic solution of uniaxial tension

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Theoretical & Applied Mechanics Letters 2018年第5期8卷 351-354,363页

作者： Zaixing huang State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

We solve the local uniaxial tension of an infinite rod in the framework of non-ordinary state-based *** singular solutions of stress and displacement are *** the influencing range of the window function approaches zero,these two solutions will return to the solutions of the classical *** analysis shows that the singularities of the solutions stem from such a feature of the window function that must be represented by a rapidly decreasing function in *** to the classical elasticity,the stress solution of peridynamics is smoother than the displacement *** addition,a criterion used to select the window function is proposed in this paper.

关键词： Peridynmics Non-ordinary state-based peridynamics Singularity Local uniaxial tension Analytical solution

Characteristic analysis and design of near moon abort trajectory for manned lunar landing mission

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Science China(Technological Sciences) 2010年第11期53卷 3129-3137页

作者： huang WenDe XI XiaoNing WANG Wei College of Mechatronics Engineering and Automation National University of Defense TechnologyChangsha 410073China College of Aerospace and Material Engineering National University of Defense TechnologyChangsha 410073China School of Surveying and Spatial Information System University of New South WalesSydneyNSW 2052Australia

The safety of astronauts would be severely threatened if the lunar-landing spacecraft were under an emergency during the near moon phase of flight, which was far from the Earth. For the problem of mission abort caused by the main engine (service propulsion system, SPS) failure during lunar orbit insertion, firstly, the family of trajectories resulted from SPS premature shutdown and corresponding abort trajectories were analyzed; then an algorithm that can be applied to the near moon abort trajectories was proposed using patched-conic technique. The characteristics of the abort trajectory, such as energy consumption and return time of flight, were analyzed and presented. Finally, simulation examples were given to demonstrate various cases of near moon SPS failure. The results of the simulation have validated the approach proposed.

关键词： manned lunar landing mission abort trajectory near moon phase characteristic analysis patched-conic technique