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Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying Dong yanqing Wu Kun yang Xiao Hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

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Stress-induced phase transformation and phase boundary sliding in Ti: An atomically resolved in-situ analysis

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Journal of Materials Science & Technology 2023年第21期152卷 30-36页

作者： Zongde Kou Xuteng Li Rong Huang Lixia yang yanqing yang Tao Feng Si Lan Gerhard Wilde Qingquan Lai Song Tang Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Institute of Materials Physics University of MuensterWilhelm-Klemm Street 10Muenster 48149Germany Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing 210009China

In-situ tensile experiments on pure Ti were performed in a transmission electron microscope at room *** dynamic process of stress-induced hexagonal closed-packed(hcp)to face-centered cu-bic(fcc)structural transformation ahead of a crack tip was captured at the atomic ***,a sliding behavior of the ensuing(0001)hcp/(1¯11)_(fcc) phase boundary was observed to further accommodate the plastic deformation until crack *** sliding was accomplished via the successive conserva-tive glide of extended dislocations along the(0001)hcp/(1¯11)_(fcc) phase boundary.A molecular dynamics simulation was carried out to corroborate the experiments and the results confirm the new dislocation-mediated sliding mechanism.

关键词： In situ HRTEM Hcp-to-fcc transformation Pure Ti Phase boundary sliding Molecular dynamics simulation

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Twinning Behaviour in the Intermetallic Compound Al_(18)Cr_2Mg_3

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 677-681页

作者： Maohua Li yanqing yang Ming Han Wei Zhang Bin Huang Xian Luo Jigang Ru State Key Laboratory of Solidification Processing Northwestern Polytechnical University Beijing Institute of Aeronautical Materials

The twinning in the intermetallic compound Al18Cr2Mg3 was observed and identified by transmission electron *** geometric description of the twinning in Al18Cr2Mg3 with 184 atoms per unit cell was investigated at atomic *** classical theory of deformation twinning states that the net atomic displacements are divided into shear and shuffles during *** on the theory and the hypothesis of full mirror reflection symmetry,the displacement and angle of shuffle were calculated for each *** geometric calculation results show that all of the atoms in single crystal Al18Cr2Mg3 have to ***,the calculation results can be divided into 22 groups,which do not show obvious regularity.

关键词： Intermetallic compound Al18Cr2Mg3 Twinning Shear Shuffle

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Superb strength and ductility balance of a Co-free medium-entropy alloy with dual heterogeneous structures

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Journal of Materials Science & Technology 2022年第3期98卷 197-204页

作者： Wenjie Lu Kang Yan Xian Luo Yuetang Wang Le Hou Pengtao Li Bin Huang yanqing yang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Langu Institute for Materials Analysis Co.Ltd Weihai 264207China Institute of optics and electronics Chinese Academy of SciencesChengdu 610200China

In present work,we successfully fabricated a novel Co-free non-equiatomic Ni_(46)Cr_(23)Fe_(23)Al_(4)Ti_(4)mediumentropy alloy with dual heterogeneous structures,***-levels grain structures and heterogeneous L1;*** results revealed the dual heterogeneous structures lead to remarkable strength-ductility synergy properties in this Co-free medium-entropy alloy,showing high yield strength and ultimate tensile strength of~1203 MPa and~1633 MPa,respectively,remaining an excellent ductility of~28.7%.Further analyses about strengthening and deformation mechanisms indicated precipitation hardening and hetero-deformation induced hardening contribute the majority strength enhancement,meanwhile deformation-induced hierarchical stacking-faults networks,high density Lomer-Cottrell locks and microstructure features of heterogeneous grains and precipitates substantially facilitate the high work-hardening capacity and excellent tensile *** work not only offers fundamental understanding of the strength and deformation mechanisms of the dual heterogeneous structural material,but also provides useful strength design strategy for low-price high performance high/medium-entropy alloys.

关键词： Dual heterogeneous structures Medium-entropy alloy Co-free Strength-ductility synergy properties

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High temperature tensile properties,fracture behaviors and nanoscale precipitate variation of an Al-Zn-Mg-Cu alloy

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Progress in Natural Science:Materials International 2020年第1期30卷 63-73页

作者： Pan Dai Xian Luo yanqing yang Zongde Kou Bin Huang Jinxin Zang Jigang Ru State Key Laboratory of Solidification Processing Northwestern Polytechnical University Beijing Institute of Aeronautical Materials

In order to assess Al-Zn-Mg-Cu alloys as potential high temperature structural materials,the hardness,tensile properties and fracture behaviors of 7085 Al alloy were investigated at various temperatures from room temperature to 175℃.High-resolution transmission electron microscopy was used to investigate the evolutions of precipitates at different temperatures,particularly on the relationship between microstructural evolution and tensile *** results reveal that both the microstructure and mechanical properties of the alloy are quite sensitive to the environmental *** the temperature increases,the hardness and strength decrease while the elongation and reduction of area *** tensile testing temperature rises,the strain hardening exponent(n) decreases due to the thermal softening *** fracture mode of the alloy transforms from mixture of intergranular and transgranular fracture to completely transgranular dimples when tensile testing temperature reaches 150℃.The precipitate sequence during high temperature tests is coincident with that of *** the increase of tensile testing temperature,the mean precipitate radius grows larger,and the distribution of grain boundary precipitates transforms from continuous to discontinuous.

关键词： 7085 Al alloy Fracture mode Microstructure evolution Tensile strength

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Peripheral Mechanism of Cancer-Induced Bone Pain

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Neuroscience Bulletin 2024年第6期40卷 815-830页

作者： Yachen yang Wei yang Ruofan Zhang yanqing Wang Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesShanghai Medical CollegeInstitute of Acupuncture ResearchInstitutes of Integrative MedicineFudan UniversityShanghai200032China Shanghai Key Laboratory of Acupuncture Mechanism and Acupoint Function Shanghai Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceInstitutes of Brain ScienceFudan UniversityShanghai200032China Zhongshan-Fudan Joint Innovation Center Zhongshan528437China

Cancer-induced bone pain(CIBP)is a type of ongoing or breakthrough pain caused by a primary bone tumor or bone *** constitutes a specific pain state with distinct characteristics;however,it shares similarities with inflammatory and neuropathic *** present,although various therapies have been developed for this condition,complete relief from CIBP in patients with cancer is yet to be ***,it is urgent to study the mechanism underlying CIBP to develop efficient analgesic ***,we focused on the peripheral mechanism associated with the initiation of CIBP,which involves tissue injury in the bone and changes in the tumor microenvironment(TME)and dorsal root *** nerve–cancer and cancer–immunocyte cross-talk in the TME creates circumstances that promote tumor growth and metastasis,ultimately leading to *** peripheral mechanism of CIBP and current treatments as well as potential therapeutic targets are discussed in this review.

关键词： Cancer-induced bone pain Peripheral mechanism Tumor microenvironment Sensory nerve Immunocytes

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2,6-二甲氧基-1,4-苯醌通过抑制NLRP3炎症小体活化缓解小鼠的感染性休克

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南方医科大学学报 2024年第6期44卷 1024-1032页

作者：张玮邓蒙蒙曾尧刘辰菲尚菲菲许文豪蒋昊轶王凤超杨燕青蚌埠医科大学第一附属医院检验科安徽蚌埠233004 蚌埠医科大学慢性疾病免疫学基础与临床安徽省重点实验室安徽蚌埠233030

目的探究发酵小麦胚芽提取物主要活性成分2,6-二甲氧基-1,4-苯醌(DMQ)抑制NLRP3炎症小体活化并缓解小鼠感染性休克的作用机制。方法细胞学水平:在BMDM细胞中,经脂多糖(LPS)预处理、DMQ干预后,利用尼日利亚菌素(Nigericin)、ATP、尿酸... 详细信息

目的探究发酵小麦胚芽提取物主要活性成分2,6-二甲氧基-1,4-苯醌(DMQ)抑制NLRP3炎症小体活化并缓解小鼠感染性休克的作用机制。方法细胞学水平:在BMDM细胞中,经脂多糖(LPS)预处理、DMQ干预后,利用尼日利亚菌素(Nigericin)、ATP、尿酸钠结晶(MSU)分别活化经典NLRP3炎症小体以及胞内转染LPS活化非经典NLRP3炎症小体。利用聚脱氧腺苷酸(Poly A:T)活化AIM2炎症小体。在THP-1细胞中,利用Nigericin活化经典NLRP3炎症小体,通过Western blotting和ELISA方法测定NLRP3炎症小体活化产物的表达水平。蛋白分子水平:利用免疫共沉淀探究DMQ阻断NLRP3炎症小体活化的具体机制。动物水平:将8周龄雄性C57BL/6J小鼠随机分为空白对照组、感染性休克LPS组、DMQ 20 mg/kg治疗组、DMQ 40 mg/kg治疗组,6只/组,待DMQ治疗组小鼠预注射相应浓度DMQ后,对照组小鼠注射无菌PBS,其余3组小鼠腹腔注射相同剂量LPS,利用ELISA检测DMQ干预对LPS诱导的小鼠感染性休克模型中血清和腹腔灌洗液中TNF-α和IL-1β分泌水平的影响。DMQ预处理后注射LPS观察记录小鼠36 h内的生存状态并绘制生存曲线。结果 DMQ可有效抑制小鼠BMDM细胞和人THP-1细胞中经典NLRP3炎症小体活化(P0.05)。进一步实验结果揭示DMQ可阻断ASC和NLRP3之间的相互作用。DMQ治疗组可显著降低小鼠血清和腹腔液中IL-1β的分泌水平(P<0.05)并延长小鼠生存时间(P<0.05)。结论发酵小麦胚芽提取物主要活性成分DMQ通过阻断ASC和NLRP3之间的相互作用有效抑制NLRP3炎症小体活化并缓解LPS诱导的小鼠感染性休克。

关键词： 2 6-二甲氧基-1 4-苯醌 NLRP3炎症小体感染性休克发酵小麦胚芽提取物

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Preparation and Characterization of Ag_2S/PMMA Nanocomposites by Microemulsion

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 175-179页

作者： Yuzhen Li Lizhen Gao Wenjun Chen Weike Zhang Lili Gao yanqing yang Likun Shang Meilu Wang College of Environmental Science and Engineering Taiyuan University of Technology School of Mechanical Engineering University of Western Australia35 Stirling HighwayCrawleyWA 6009Australia Department of Neurology Shanxi Provincial People's Hospital

Ag2S nanoparticles in polymethyl methacrylate （PMMA） are prepared in n-heptane/sodium bis（2-ethyl- hexyl）sulfosuccinate/water microemulsions. The Ag2S nanoparticles dispersed in the polymer are characterized by FT-IR spectrum, UV-Vis absorption spectroscopy, transmission electron microscopy （TEM）, and X-ray powder diffraction （XRD）. The FT-IR spectrum shows that the composite has the characteristic bands of nano-Ag2S and pure PMMA. The TEM photograph of the sample shows that the Ag2S nanoparticles are elliptical. The phase structure of the composite is characterized by XRD, which reveals that Ag2S particles are formed. The UV-Vis absorption recorded at various times indicates an initial rapid formation of the nanoparticles and the quantum confinement effect of Ag2S nanoparticles.

关键词： Nanoparticle Nanocomposite Coating

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血小板源性生长因子BB调控缺氧诱导因子1α表达在缺氧性肺动脉高压新生大鼠肺血管重塑中的机制研究

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中华新生儿科杂志（中英文） 2024年第3期39卷 168-176页

作者：杨延青巴依尔才次克郭鑫王乐新疆医科大学儿科学院乌鲁木齐830054 新疆医科大学第一附属医院新生儿科乌鲁木齐830054 商丘市中医院儿科商丘476000

目的探讨血小板源性生长因子BB(platelet-derived growth factor-BB,PDGF-BB)是否通过调控缺氧诱导因子1α(hypoxia induced factor-1 alpha,HIF-1α)表达促进肺动脉平滑肌细胞增殖以及参与缺氧性肺动脉高压(hypoxic pulmonary hypertension,HPH)的肺血管重塑。方法160只Wistar新生大鼠按随机数字表法分为常氧组、HPH组、常氧+PDGF-BB组、HPH+PDGF-BB组、HPH+PDGF-BB抑制剂(STI571)组,每组各32只,每组再分为第3、7、14、21天4个亚组,每组8只。PDGF-BB组经尾静脉注射载有PDGF-BB的腺病毒、HPH+STI571组给予STI571灌胃;缺氧建立新生大鼠HPH模型,建模后第3、7、14、21天检测平均右心室收缩压(right ventricular systolic pressure,RVSP),苏木素-伊红染色观察肺小动脉形态变化及检测肺血管重塑指标,免疫组化测定各组PDGF-BB、HIF-1α及增殖相关蛋白核蛋白Ki67在肺血管中的表达部位和表达水平,实时荧光定量聚合酶链反应检测肺组织中PDGF-BB、HIF-1α及Ki67的mRNA水平。结果各时间点HPH组RVSP均高于常氧组(P<0.05),HPH+PDGF-BB组RVSP均高于HPH组(P<0.05),HPH+STI571组RVSP均低于HPH+PDGF-BB组与HPH组(P<0.05);建模后第3天HPH+PDGF-BB组发生肺血管重塑,第7天常氧+PDGF-BB组和HPH组发生肺血管重塑,HPH+STI571组肺血管重塑出现较晚且程度较其他缺氧组轻;第3、7、21天HPH+PDGF-BB组PDGF-BB、HIF-1α、Ki67蛋白及mRNA表达水平均高于其他组(P<0.05),各时间点HPH+STI571组PDGF-BB、HIF-1α、Ki67蛋白及mRNA表达水平均低于HPH+PDGF-BB组和HPH组(P<0.05)。结论PDGF-BB通过上调HIF-1α表达水平促进肺动脉平滑肌细胞增殖、加重肺血管重塑,从而提高HPH新生大鼠肺动脉压力。

关键词：血小板源性生长因子BB 缺氧诱导因子1α 肺动脉高压血管重塑新生大鼠

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Evaluating Suitability of Multiple Precipitation Products for the Lancang River Basin

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Chinese Geographical Science 2019年第1期29卷 37-57页

作者： TANG Xiongpeng ZHANG Jianyun WANG Guoqing yang Qinli yang yanqing GUAN Ti-esheng LIU Cuishan JIN Junliang LIU Yanli BAO Zhenxin Nanjing Hydraulic Research Institute State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University University of Electronic Science and Technology of China

Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sources are suitable for all regions or perform the same way in hydrological modeling, so it is essential to test the suitability of precipitation products before applying them. In this study, five widely used global high-resolution precipitation products—Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources(APHRODITE), National Centers for Environmental Prediction Climate Forecast System Reanalysis(NCEP-CFSR), Climate Hazards Group InfraRed Precipitation with Station Data(CHIRPS), China Gauge-based Daily Precipitation Analysis developed by China Meteorological Administration(CMA) and Agricultural Model Intercomparison and Improvement Project based on the NASA Modern-Era Retrospective Analysis for Research and Applications(AgMERRA)—were evaluated using statistical methods and a hydrological approach for their suitability for the Lancang River Basin. The results indicated that APHRODITE, CMA, AgMERRA and CHIRPS were more accurate precipitation indicators than NCEP-CFSR in terms of the multiyear average and seasonal spatial distribution pattern, all of the CHIRPS, Ag MERRA and APHRODITE perform better than CMA and NCEP-CFSR at the small, medium and high precipitation intensities ranges in subbasin11 and sunbabsin46. All five products performed better in subbasin46(a low-altitude region) than in subbasin11(a high-altitude region) on the daily and monthly scales. In addition to NCEP-CFSR, the other four products all presented encouraging potential for streamflow simulation at daily(Yunjinghong) and monthly(Yunjinghong, Jiuzhou and Gajiu) scale. Hydrological simulations forced with APHRODITE were the best of the five for the Yunjinghong station in capturing daily and monthly measured streamflow. Except for NCEP-

关键词： multiple precipitation products suitability evaluation the Lancang River Basin

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