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直升机核生化防护体系集成设计与仿真

空军工程大学学报 2024年第1期25卷 17-24页

作者：毛晓东张策王鹤翔李洋王伟华沈阳航空航天大学航空发动机学院沈阳110136

直升机作为国家战略层次的飞行器,其快速进出战场的能力必将在核生化威胁中起到关键作用。为了保障舱内人员的安全,必须对直升机的核生化防护系统进行研究。从系统顶层架构设计出发,基于系统集成手段,设计了一种直升机核生化防护体系。... 详细信息

直升机作为国家战略层次的飞行器,其快速进出战场的能力必将在核生化威胁中起到关键作用。为了保障舱内人员的安全,必须对直升机的核生化防护系统进行研究。从系统顶层架构设计出发,基于系统集成手段,设计了一种直升机核生化防护体系。针对各子系统开展了详细构型设计,包括:基于小型高转速电动压气机的气源增压子系统;基于变压吸附原理,可实现机载实时再生的滤毒通风子系统;基于热泵型蒸发制冷循环,利用滑油废热及双蒸发器并联驱动的温度控制子系统;综合座舱超压防护及增压需求的压力调节子系统。基于系统构型,建立了仿真模型,对系统动态性能开展了仿真验证研究。仿真结果表明:在各种极端条件下,舱内压力、温度均满足设计要求。当进入核生化威胁区域时,滤毒通风子系统能够有效吸附有毒物质,吸附床通过机载实时再生,延长了在核生化威胁区域的作业时间,为直升机核生化防护系统设计提供了新的思路。

关键词：核生化防护直升机座舱变压吸附蒸发制冷循环飞行动态特性

不等厚6016-T4P三层板电阻点焊工艺窗口调控技术

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焊接 2024年第5期 63-68页

作者：刘庆永毛晓东宋小雨徐志强李英东王国军中铝材料应用研究院有限公司北京100029

通过电阻点焊工艺性试验,分析2.5 mm,3.2 mm,2.0 mm 3种厚度6016-T4P板材搭接焊点熔核形成过程,并采用主机厂常用的2种不同形状电极帽(ϕ16R20,ϕ20R100)分别进行工艺性测试,建立对应电阻点焊焊接工艺窗口,同时分析了电极压力和电极帽形... 详细信息

通过电阻点焊工艺性试验,分析2.5 mm,3.2 mm,2.0 mm 3种厚度6016-T4P板材搭接焊点熔核形成过程,并采用主机厂常用的2种不同形状电极帽(ϕ16R20,ϕ20R100)分别进行工艺性测试,建立对应电阻点焊焊接工艺窗口,同时分析了电极压力和电极帽形状对于焊接工艺窗口偏移的影响。结果表明,采用ϕ16R20电极帽时,电极压力的变化(3.5~5.5 kN)可使焊点可用最小焊接电流变化3 kA的幅度,采用ϕ20R100电极帽时,电极压力的变化(3.5~5.5 kN)可使焊点可用最小焊接电流变化1 kA的幅度,在相同焊接工艺参数(电极压力4.5 kN、焊接时间200 ms、保持时间150 ms)条件下,电极帽形状(ϕ16R20,ϕ20R100)的变化可使焊点可用最小焊接电流变化5 kA的幅度。通过该文的研究成果,可显著改善铝合金生产厂在材料推广应用中遇到的电阻点焊工艺窗口不吻合的情况,方便材料切换,利于铝合金在主机厂的推广应用。

关键词： 6016-T4P 电阻点焊电极帽工艺窗口调控

Comparative study of β-Si_3N_4 powders prepared by SHS sintered by spark plasma sintering and hot pressing

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Journal of University of Science and Technology Beijing 2007年第3期14卷 271-275页

作者： Ling Bai xiaodong mao Weiping Shen Changchun Ge Laboratory of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

β-Si3N4 powders prepared by self-propagating high-temperature synthesis （SHS） with additions of Y2O3 and Al2O3 were sintered by spark plasma sintering （SPS）. The densification, microstructure, and mechanical properties of Si3N4 ceramics prepared using this method were compared with those obtained by hot pressing process. Well densified Si3N4 ceramics with finer and homogeneous microstructure and better mechanical properties were obtained in the case of the SPS technique at 200°C lower than that of hot pressing. The microhardness is 15.72 GPa, the bending strength is 716.46 MPa, and the fracture toughness is 7.03 MPa·m1/2.

关键词： self-propagating high-temperature synthesis (SHS) hot pressing spark plasma sintering (SPS) silicon nitride mechanicalproperties

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,China:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping mao Guangzhou LI Min LIU Pengrui MA xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,China,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

Direct observation of oxygen vacancy formation and migration over ceria surface by in situ environmental transmission electron microscopy

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Journal of Rare Earths 2024年第4期42卷 676-682页

作者： Dawei Pang Wei Li Ningqiang Zhang Hong He Shengcheng mao Yanhui Chen Liwei Cao Chong Li Ang Li xiaodong Han Beijing Key Laboratory of Solid Microstructure and Properties Department of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation The Faculty of Environment and LifeBeijing University of TechnologyBeijing10124China International Joint Research Laboratory for Quantum Functional Materials of Henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China

The extremely high structural tolerance of ceria to oxygen vacancies(Ov)has made it a desirable catalytic material for the hydrocarbon oxidation to chemicals and pharmaceuticals and the reduction of gaseous *** is proposed that the formation and diffusion of Ov originate from its outstanding reduction ***,the formation and diffusion process of Ov over the surface of ceria at the atomic level is still ***,the structural and valence evolution of CeO_(2)(111)surfaces in reductive,oxidative and vacuum environments from room temperature up to 700℃was studied with in situ aberration-corrected environmental transmission electron microscopy(ETEM)*** is found to form under a high vacuum at elevated temperatures;however,the surface can recover to the initial state through the adsorption of oxygen atoms in an oxygen-contained ***,in hydrogen environment,the step-CeO_(2)(111)surface is not stable at elevated temperatures;thus,the steps tend to be eliminated with increasing *** with first-principles density function calculations(DFT),it is proposed that O-terminated surfaces would develop in a hypoxic environment due to the dynamic diffusion of Ov from the outer surface to the ***,in a reductive environment,H2 facilitates the formation and diffusion of Ov while Ce-terminated surfaces *** results reveal dynamic atomic-scale interplay between the nanoceria surface and gas,thereby providing fundamental insights into the Ov-dependent reaction of nano-CeO_(2) during catalytic processes.

关键词： Ceria Direct observation In situ ETEM Oxygen vacancy Density function calculations Rareearths

Densification,microstructure,and fracture behavior of TiC/Si_3N_4 composites by spark plasma sintering

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Rare Metals 2008年第3期27卷 315-319页

作者： BAI Ling GE Changchun SHEN Weiping mao xiaodong ZHANG Ke Laboratory of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

TiC/Si3N4 composites were prepared using the β-Si3N4 powder synthesized by self-propagating high-temperature synthesis （SHS） and 35 wt.% TiC by spark plasma sintering. Y2O3 and Al2O3 were added as sintering additives. The almost full sintered density and the highest fracture toughness （8.48 MPa·m1/2） values of Si3N4-based ceramics could be achieved at 1550℃. No interfacial interactions were noticeable between TiC and Si3N4. The toughening mechanisms in TiC/Si3N4 composites were attributed to crack deflection, microcrack toughening, and crack impedance by the periodic compressive stress in the Si3N4 matrix. However, increasing microcracks easily led to excessive connection of microcracks, which would not be beneficial to the strength.

关键词： silicon nitride titanium carbide spark plasma sintering (SPS) microstructure fracture behavior

Carbon isotope composition and comparison of Lower Triassic marine carbonate rocks from Southern Longmenxia section in Guang＇an, Sichuan Basin

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Science China Earth Sciences 2017年第1期60卷 80-94页

作者： HUANG SiJing HUANG KeKe ZHONG YiJiang LI XiaoNing mao xiaodong HU ZuoWei LIU SiBing ZHANG Meng WU WenHui State Key Laboratory of OilGas Reservoir Geology and Exploitation Institute of Sedimentary Geology Chengdu University of Technology Chengdu 610059 China

The Early Triassic was a period of ecological restoration for the earth's system after the end-Permian mass *** records linked to the variations in marine ecosystems during this period have attracted the interest of geologists for many *** on petrographic analysis of samples and evaluations of their reliability as proxies for original seawater,this study investigated the carbon and oxygen isotopic compositions of 350 carbonate rock samples from the Lower Triassic(and adjacent strata)in the southern Longmenxia section of Guang'an,eastern Sichuan *** results indicate that the Triassic carbonate rocks from the southern Longmenxia section favorably preserved the original seawater'sδ^(13)C ***,carbon and oxygen isotopic compositions are found to be poorly correlated,with a determination coefficient as low as 0.0205 and only 44 rock samples show results of Mn/Sr>2 and/orδ^(18)0-6.5‰.This curve presents favorable comparability on a global scale,specifically in theδ^(13)C minima near the Permian-Triassic boundary,at the top of the Jia1 and within the the Jia3,as well as in theδ^(13)C maxima at the tops of the Ye1 and Ye4,at the base of the Jia2 and at the top of the *** peaks and troughs corresponding to these maxima and minima all reflect global *** comparing these results to previous research on coeval carbon isotopic curves established within the chronostratigraphic framework,the ages of these critical evolution points are *** results show that the Ye1 roughly corresponds to the Griesbachian substage;the Ye2 through Ye4 correspond to the Dienerian substage;Jial corresponds to the Smithian substage;from the Jia2 to the lower part of the Jia4 correspond to the Spathian substage;and the middle and upper parts of the Jia4 belongs to the Aegean Substage of

关键词： Southern Longmenxia section Early Triassic Carbon isotopic composition Global events Smithian-Spathian boundary event

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基于云平台的远程煤炭设备故障诊断系统研究

煤炭技术 2022年第9期41卷 167-169页

作者：毛晓东白刚永城职业学院河南永城476600 辽宁工程技术大学安全科学与工程学院辽宁阜新123000

智慧矿山是未来煤矿企业发展的必然方向,煤矿开采环境恶劣,煤炭设备故障时有发生,远程故障诊断技术可更快地响应,保障开采的高效开展,因此研究煤炭设备远程故障诊断系统。归纳总结采煤机、矿用提升机和带式输送机的常见故障部位以及为... 详细信息

智慧矿山是未来煤矿企业发展的必然方向,煤矿开采环境恶劣,煤炭设备故障时有发生,远程故障诊断技术可更快地响应,保障开采的高效开展,因此研究煤炭设备远程故障诊断系统。归纳总结采煤机、矿用提升机和带式输送机的常见故障部位以及为诊断其故障需监测的参数,采用云平台构建煤炭设备远程故障诊断系统架构,分析架构层与层之间的关系,研究远程故障诊断的核心技术并详细设计专家诊断中心远程故障诊断的具体流程。

关键词：云平台远程故障诊断专家系统煤炭设备

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology Department of Materials Science and Engineering City University of Hong Kong Key Laboratory of Partial Acceleration Physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences Department of Materials Science &Engineering Southern University of Science and Technology Department of Physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation