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The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 114-124页

作者： Yifan xie Jian-Li shao Rui Liu Pengwan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing100039China

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics *** the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main *** reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following *** reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our ***,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al *** can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed *** shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal *** addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

关键词： Shock-induced reaction Molecular dynamics simulations Interfacial crystallization Reaction mechanism

双碳目标背景下电力集团储能电站与传统能源碳减排投资决策

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管理工程学报 2025年第1期39卷 214-226页

作者：宋明珍谢吉青孔令丞谢家平上海财经大学商学院新疆财经大学工商管理学院华东理工大学商学院

为有效调整电力集团能源结构以支撑我国双碳目标的实现,电力集团储能电站与传统能源碳减排(CCUS机组)投资决策研究已成为当下亟待研究的热点问题。为此,本文同时考虑风电间歇性与高峰期电力需求存在随机波动情景,将分时定价研究框架运... 详细信息

为有效调整电力集团能源结构以支撑我国双碳目标的实现,电力集团储能电站与传统能源碳减排(CCUS机组)投资决策研究已成为当下亟待研究的热点问题。为此,本文同时考虑风电间歇性与高峰期电力需求存在随机波动情景,将分时定价研究框架运用至储能电站与CCUS机组联合投资决策模型构建中,以研究不同策略下电力集团储能电站或CCUS机组最优投资决策与最优策略选择。研究发现:(1)各投资策略均存在最优容量水平,但需要储能电站与CCUS机组单位投资成本、CCUS机组单位运营成本满足一定上限条件,且最优容量受化石能源消费占比约束影响明显;除碳价较低且CCUS机组单位运营成本偏高情形外,联合投资(ST)策略始终是利润视角下的最优投资策略。(2)提高碳价、降低峰谷电价差值会提升最优投资容量,较高的发电与运营成本将降低最优CCUS机组容量;投资储能电站能够降低减排强度阈值,对CCUS机组产生一定的减排挤出效应。(3)当电力需求价格敏感度偏高且峰谷电价差值较大、碳价与CCUS机组单位运营成本同步增加、单位投资成本差异较大时,单一投资(NT或SN)策略碳排放水平最低,否则,ST策略始终为最优投资策略。

关键词：容量决策储能 CCUS机组双碳目标电力集团

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Spatiotemporal variations of PM_(2.5) and PM_(10) concentrations between31 Chinese cities and their relationships with SO_2,NO_2,CO and O_3

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Particuology 2015年第3期13卷 141-149页

作者： Yangyang xie Bin Zhao Lin Zhang rong Luo Department of Building Science School of ArchitectureTsinghua University Department of Electronic Engineering Tsinghua University

The variations of mass concentrations of PM2.5, PMl0, SO2, NO2, CO, and 03 in 31 Chinese provincial capital cities were analyzed based on data from 286 monitoring sites obtained between March 22, 2013 and March 31,2014. By comparing the pollutant concentrations over this length of time, the characteristics of the monthly variations of mass concentrations of air pollutants were determined. We used the Pearson correlation coefficient to establish the relationship between PM2.5, PM10, and the gas pollutants. The results revealed significant differences in the concentration levels of air pollutants and in the variations between the different cities. The Pearson correlation coefficients between PMs and NO2 and SO2 were either high or moderate （PM2.s with NO2： r = 0.256-0.688, mean r = 0,498：PM10 with NO2： r = 0.169-0.713, mean r=0.493; PM2.5 with SO2： r=0.232-0.693, mean r=0.449; PM10 with SO2： r=0.131-0.669, mean r = 0.403）. The correlation between PMs and CO was diverse （PM2.5： r = 0.156-0.721, mean r = 0.437; PMl0： r= 0.06-0.67, mean r= 0.380）. The correlation between PMs and 03 was either weak or uncorrelated （PM2.s： r= -0,35 to 0.089, mean r= -0.164; PM10： r= -0.279 to 0.078, mean r= -0.127）, except in Haikou （PM2.5： r=0.500; PM10： r=0,509）.

关键词： PM2.5PM40 Atmospheric air pollutantIndoor environmentOutdoor environment

System Identification Method for Small Unmanned Helicopter Based on Improved Particle Swarm Optimization

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Journal of Bionic Engineering 2016年第3期13卷 504-514页

作者： Oi Bian Kairui Zhao Xinmin Wang rong xie School of Automation Northwestern Polytechnical University Xi 'an 710129 China

This paper proposes a novel method for Small Unmanned Helicopter （SUH） system identification based on Improved Particle Swarm Optimization （IPSO）. In the proposed IPSO, every particle will do a local search as a ＂self-check＂ before up- dating the global velocity and position. Then, the global best particle is created by a certain number of elitist particles in order to get a rapid rate of convergence during calculation. Thus both the diversity and convergence speed can be taken into considera- tion during a search. Formulated by the first principles derivation, a state-space model is built for the analysis of dynamic modes of an experimental SUH. The helicopter is equipped with an Attitude Heading Reference System （AHRS） and the corresponding data storage modules, which are used for flight test data measurement and recording. After data collection and reconstruction, the input and output data are utilized to determine the corresponding aerodynamic parameters of the state-space model. The predictive accuracy and fidelity of the identified model are verified by making a time-domain comparison between the responses from the simulation model and the responses from actual flight experiments. The results show that the characteristics of the experimental SUH can be determined accurately using the identified model and the new method can be used for SUH system identification with high efficiency and reliability.

关键词： small unmanned helicopter state-space model system identification improved particle swarm optimization

交联型聚乙烯醇纸张表面施胶剂的制备及其应用

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陕西科技大学学报 2025年第1期43卷 1-7页

作者：费贵强李实肖文娟杨晨榕解攀陕西科技大学化学与化工学院陕西省轻化工助剂重点实验室陕西西安710021 西安北方惠安化学工业有限公司陕西西安710302

为了改善聚乙烯醇、淀粉作为纸张表面施胶剂的应用性能,选用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和硼砂(STB)为交联剂,交联改性淀粉(PS)和聚乙烯醇(PVA1799),制备出不同交联程度的纸张表面施胶剂(CPSn-PVA).通过傅里叶红外光谱(FT-I... 详细信息

为了改善聚乙烯醇、淀粉作为纸张表面施胶剂的应用性能,选用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和硼砂(STB)为交联剂,交联改性淀粉(PS)和聚乙烯醇(PVA1799),制备出不同交联程度的纸张表面施胶剂(CPSn-PVA).通过傅里叶红外光谱(FT-IR),扫描电镜(SEM)及稳定性测试对纸张表面施胶剂的性能进行了表征,探讨了KH560和STB的添加比例对纸张施胶剂的性能以及施胶后纸张物理性能的影响.实验结果表明,当STB添加量为0.1 g、KH560添加量为3 g时,纸张施胶剂膜拉伸强度可达25.6 MPa、断裂伸长率为326%.同时,与原纸相比,多重交联型纸张表面施胶剂表现出良好的应用性能,施胶后的纸张耐折次数、撕裂指数、接触角分别提升了6700%、65.04%、89.7%.

关键词：表面施胶剂改性淀粉聚乙烯醇硅烷偶联剂稳定性耐折度

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： Xian-rong Wu Xiao-Hong He Yong-Fang xie School of Life Health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy

Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： shao-Qi Huang Jun-Qi Zhang Yong Zhu Ling-Min Kong Lu-Sheng Liao Fu-Quan Zhang Zheng-Tian xie Jin-rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property

Cu_2ZnSnS_4 thin films prepared by sulfurization of ion beam sputtered precursor and their electrical and optical properties

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Rare Metals 2006年第z1期25卷 315-319页

作者： ZHANG Jun shao Lexi FU Yujun xie Erqing School of Physics Science and Technology Zhanjiang Normal University Zhanjiang 524048 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China School of Physics Science and Technology Zhanjiang Normal University Zhanjiang 524048 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China

Cu2ZnSnS4 (CZTS) thin films were successfully prepared by sulfurization of ion bean sputtered precursors on soda-lime glass substrate. The single phase of stannite-type structure CZTS films were obtained as revealed in EDS and XRD analysis when the ratios of the constituents of CZTS thin films are close to stoichiometric by optimizing the conditions of precursor preparation and sulfurization. A low sheet resistivity as about 0.156 Ω·cm and a high absorption coefficient as 1×104 cm-1 were achieved in this method by Hall effect measurements and UV-VIS spectrophotometer. The optical band-gap energy of the CZTS sample is about 1.51 eV, which is very close to the optimum value for a solar-cell absorber.

关键词： Cu2ZnSnS4 thin film solar-cell ion beam sputtering

Modularity-like objective function in annotated networks

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Frontiers of physics 2017年第6期12卷 109-113页

作者： Jia-rong xie Bing-Hong Wang Department of Modern Physics University of Science and Technology of China Hefei 230026 China

We ascertain the modularity-like objective function whose optimization is equivalent to the maximum likelihood in annotated networks. We demonstrate that the modularity-like objective function is a lin- ear combination of modularity and conditional entropy. In contrast with statistical inference methods, in our method, the influence of the metadata is adjustable; when its influence is strong enough, the metadata can be recovered. Conversely, when it is weak, the detection may correspond to another partition. Between the two, there is a transition. This paper provides a concept for expanding the scope of modularity methods.

关键词： community structure annotated networks modularity objective function