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基于图论的复杂系统潜通路分析方法

兵器装备工程学报 2024年第6期45卷 40-46页

作者：刘向宏李志峰孙仕强中国人民解放军93160部队北京100041 北京航空航天大学可靠性与系统工程学院北京100191

潜通路分析方法是可靠性分析中一种常用的方法,是减少设计问题,提升可靠性的一种重要手段。当前的潜通路分析方法主要是应用于电路系统分析,也有部分包含管路系统的应用,但是还没有适用于复杂系统的潜通路分析方法。针对上述问题,提出... 详细信息

潜通路分析方法是可靠性分析中一种常用的方法,是减少设计问题,提升可靠性的一种重要手段。当前的潜通路分析方法主要是应用于电路系统分析,也有部分包含管路系统的应用,但是还没有适用于复杂系统的潜通路分析方法。针对上述问题,提出了一种基于图论的系统潜通路分析方法,首先构建基于流的系统模型,然后将模型中不影响分析的连接关系及模型节点简化,最后将系统模型转换为抽象的图模型,并利用节点识别和路径追踪的方法进行分析。最后,将所提方法应用于直升机起落架误收问题的分析,证明了所提方法的有效性。

关键词：潜通路分析复杂系统系统建模图论路径搜索

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钛合金铸锭尾部冶金质量影响因素研究

稀有金属材料与工程 2024年第9期53卷 2565-2570页

作者：赵小花王凯旋王锦程楼美琪王阳阳刘鹏刘向宏西北工业大学凝固技术国家重点实验室陕西西安710072 西部超导材料科技股份有限公司陕西西安710018

采用数值模拟方法,通过从熔炼起弧阶段的能量输入(以及散热)的角度分析影响铸锭尾部冶金质量的关键因素,对第3次熔炼的起弧工艺参数进行研究,并通过实验进行了验证。结果表明,电流起弧后随着熔炼的进行,铸锭表面温度逐渐升高,在熔炼至铸... 详细信息

采用数值模拟方法,通过从熔炼起弧阶段的能量输入(以及散热)的角度分析影响铸锭尾部冶金质量的关键因素,对第3次熔炼的起弧工艺参数进行研究,并通过实验进行了验证。结果表明,电流起弧后随着熔炼的进行,铸锭表面温度逐渐升高,在熔炼至铸锭30mm高度处,表面温度达到最高。通过选择合适时机提升起弧电流大小,加快电流上升速度,可以使熔池表面温度明显上升。Φ720 mm规格TC17钛合金第3次熔炼起弧电流增大4 kA,1 min快速升至大电流,大电流保持时间延长6 min,能够实现熔池快速健全,达到稳定熔池时熔炼的金属质量减少约一半,数值模拟和实验结果的一致性吻合良好。

关键词：钛合金铸锭尾部起弧工艺数值模拟

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党史教育在“概论”课教学中的彰显与深化

高等药学教育研究 2024年第2期 7-12页

作者：马寰宇刘向红沈阳药科大学马克思主义学院辽宁沈阳110016

高校思政课是学习宣传阐释党史的重要阵地,本文通过“三个必然要求”归纳党史教育融入“概论”课的必要性,通过“三个需要”分析党史教育在“概论”课教学彰显与深化的重要性,以史实、人物、启示与教训四个方面浅析党史教育在“概论”... 详细信息

高校思政课是学习宣传阐释党史的重要阵地,本文通过“三个必然要求”归纳党史教育融入“概论”课的必要性,通过“三个需要”分析党史教育在“概论”课教学彰显与深化的重要性,以史实、人物、启示与教训四个方面浅析党史教育在“概论”课教学中彰显和深化的实践路径。

关键词：党史教育 “概论”课教育教学

Room-Temperature Gas Sensors Under Photoactivation:From Metal Oxides to 2D Materials

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Nano-Micro Letters 2020年第11期12卷 292-328页

作者： Rahul Kumar xianghong liu Jun Zhang Mahesh Kumar Department of Electrical Engineering Indian Institute of Technology JodhpurJodhpur 342037India College of Physics Center for Marine Observation and CommunicationsQingdao UniversityQingdao 266071People’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071People’s Republic of China

Room-temperature gas sensors have aroused great attention in current gas sensor technology because of deemed demand of cheap,low power consumption and portable sensors for rapidly growing Internet of things *** an important approach,light illumination has been exploited for room-temperature operation with improving gas sensor's attributes including sensitivity,speed and *** review provides an overview of the utilization of photoactivated nanomaterials in gas sensing ***,recent advances in gas sensing of some exciting different nanostructures and hybrids of metal oxide semiconductors under light illumination are ***,excellent gas sensing performance of emerging two-dimensional materialsbased sensors under light illumination is discussed in details with proposed gas sensing *** impressive features from the interaction of photons with sensing materials are elucidated in the context of modulating sensing ***,the review concludes with key and constructive insights into current and future perspectives in the light-activated nanomaterials for optoelectronic gas sensor applications.

关键词： Gas sensor Room temperature Photoactivation Metal oxide 2D materials

基于组合赋权TOPSIS模型的宿州市水资源承载力评价及障碍因子研究

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人民珠江 2024年第6期45卷 100-106页

作者：刘建奎张震刘向红魏路安徽省地质环境监测总站/安徽省地质灾害应急技术指导中心安徽合肥230001 安徽理工大学空间信息与测绘工程学院安徽淮南232001 宿州学院资源与土木工程学院安徽宿州234000

研究区域水资源承载力是发现和解决区域水资源问题的重要途径。针对皖北平原水资源短缺和水环境污染等问题,以宿州市为例,基于主体框架法构建评价指标体系,采用组合赋权的优劣解距离法对宿州市2012—2021年水资源承载力进行了评价,并引... 详细信息

研究区域水资源承载力是发现和解决区域水资源问题的重要途径。针对皖北平原水资源短缺和水环境污染等问题,以宿州市为例,基于主体框架法构建评价指标体系,采用组合赋权的优劣解距离法对宿州市2012—2021年水资源承载力进行了评价,并引入障碍度模型识别全市水资源承载力提升的障碍因素。结果表明:2012—2021年,宿州市水资源承载力状况呈现波动变化的趋势(临界超载—轻度超载—临界超载),全市水资源供需处于紧平衡状态;人均供水量、万元GPD排放COD量、城市污水处理厂日处理能力是阻碍宿州市水资源承载力提升的主要障碍因子。该评价结果及评价方法合理可靠,可为其他城市水资源承载力评价提供有益参考。

关键词：水资源承载力组合赋权 TOPSIS模型障碍因子宿州市

Responses of marine-derived Trichoderma fungi to seawater and their potential antagonistic behaviour

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Journal of Oceanology and Limnology 2019年第2期37卷 525-534页

作者： SONG Yinping MIAO Fengping liu xianghong JI Naiyun Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China University of Chinese Academy of Sciences Beijing 100049 China

To explore the metabolic responses of marine-derived Trichoderma fungi to environmental stresses, the survivability, metabolism, and antagonism of ten marine isolates have been examined. Their survival in both freshwater and seawater indicates them to be facultative marine fungi, but they are more adaptable to marine environment. Most of them feature strain-specific and positive metabolic responses to seawater, which also usually result in the higher proportions of heteroatom-bearing and unsaturated units in mycelial constituents. Seawater factors can promote many strains to produce bioactive metabolites, including plant pathogen- and marine phytoplankton-inhibitory and marine animal-toxic ones, but the eff ects of NaCl are often weak or negative. The inhibition of marine phytoplankton corresponds to the intracellular accumulation of heteroatom-bearing and unsaturated units under seawater condition, and the varied toxicities to marine animals further signify the divergences of lipophilic exudates under diff erent conditions. The results may contribute to further understanding and mining the structural diversity and biological activity of secondary metabolites from marine-derived Trichoderma fungi.

关键词： Trichoderma fungus metabolic response seawater antagonistic potential

Algicidal activities of secondary metabolites of marine macroalgal-derived endophytic fungi

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Journal of Oceanology and Limnology 2019年第1期37卷 112-121页

作者： MIAO Fengping ZUO Jincheng liu xianghong JI Naiyun Yantai Institute of Coastal Zone Research Chinese Academy of Sciences College of Life Science Ludong University

Red tide occurrs frequently and causes signi?cant damage to the environment and human health. As a result, development of new effcient and environment friendly red-tide microalgae inhibitors has gained increasing attention in recent times. Algicolous endophytic fungi with unique habitats are promising sources for active agents owing to their abundant secondary metabolites and distinguished activities. In this study, the algicidal activities of 49 marine macroalgal-derived endophytic fungi against phytoplankton Alexandrium tamarense, Prorocentrum donghaiense, Heterosigma akashiwo, and Chattonella marina were examined using 96-well microplate. Four fungal strains, including Aspergillus wentii(pt-1), A. ustus(cf-42),and A. versicolor(dl-29, pt-20), exhibited potent algicidal activities. A total of 32 pure compounds isolated from these fungi were noted to possess dif ferent degrees of algicidal activities. Of those, 11 compounds comprising ?ve anthraquinones, two terpenoids, and four steroids showed high 24-h inhibition rates for the four red tide algae, with 24 h EC_(50) values ranging from 0.01 to 14.29 μg/mL. Among them, compound1(1,5-dihydroxy-3-methoxy-7-methylanthraquinone) presented the strongest activity against H. akashiwo,and could decrease its chlorophyll a(Chl a) and superoxide dismutase contents and increase the soluble protein, malondialdehyde, and peroxidase contents. These results suggested that the identi?ed anti-algal compound might inhibit the growth of red tide algae by weakening photosynthesis(reducing Chl a content),destroying cell membrane, and damaging the antioxidant system.

关键词： algicidal activity endophytic fungus secondary metabolite marine alga

Pore defects in a nickel-based superalloy with high Ti content

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Progress in Natural Science:Materials International 2022年第4期32卷 456-462页

作者： Puying Shi Wenliang Xu Baoquan Fu Jin liu Jianing Zhang Kaixuan Wang xianghong liu Western Superconducting Technologies Co. Ltd. School of Mechanical Engineering Xi'an Jiaotong University

Pores are uncommon defects in superalloy bars, which deserve to be investigated. In this work, a type of pore defect within GH4710 nickel-based superalloy was investigated by 3D X-ray imaging method combined with metallographic analysis. 3D X-ray imaging was used for locating and visualizing the defects in the alloy. The 3D Xray imaging result of the defects showed a good agreement with the defect anatomical morphologies. It was observed that the pore defect was accompanied by MC carbides, micro-crack, and non-metallic inclusions. The origin of pore defect was attributed to the shrinkage pores, inclusion and the complex precipitates. The analysis showed that the pore defects in GH4710 alloy was associated with strong micro-segregation and complex phase precipitation during solidification, induced by the high weight content of Ti and C in the alloy.

关键词： Ni-based superalloy Defects 3D X-ray imaging High Ti content

Strongly coupled N-doped carbon/Fe3O4/N-doped carbon hierarchical micro/nanostructures for enhanced lithium storage performance

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Journal of Energy Chemistry 2019年第7期28卷 43-51页

作者： Tian tian Ma xianghong liu Li Sun Yongshan Xu Lingli Zheng Jun Zhang College of Physics Qingdao UniversityQingdao 266071ShandongChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

A strong interface coupling is of vital importance to develop metal oxide/carbon nanocomposite anodes for next-generation lithium ion ***,a rational N-doped carb on riveting strategy is designed to boost the lithium storage performance of Fe3O4/N-doped carbon tubular *** pyrrole(PPy)has been used as the precursor for N-doped carbon.N-doped carbon-riveted Fe3O4/N-doped carbon(N-C@Fe3O4@N-C)nanocomposites were obtained by pyrolysis of PPy-coated FeOOH@PPy nanotubes in Ar *** tested as an anode for LIBs,the N-C@Fe3O4@N-C displays a high reversible discharge capacity of 675.8 mA h g-1 after 100 cycles at a current density of 100 mA g-1 and very good rate capability(470 mA h g_1 at 2 A g-1),which significantly surpasses the performance of Fe3O4@*** analysis reveals that after battery cycling the FeOx particles detached from the carbon fibers for Fe3O4@N-C,while for N-C@Fe3O4@N-C the FeOx particles were still trapped in the carbon matrix,thus preserving good electrical ***,the superior performance of N-C@Fe3C)4@N-C is attributed to the synergistic effect between Fe3O4 and N-doped carbon combined with the unique structure properties of the *** strategy reported in this work is expected to be applicable for designing other electrode materials for LIBs.

关键词： Iron oxide Micro/nanostructures Carbon tubes Anode Coupling