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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 116-126页

作者： Tao Liu Mei Yang jun-song Wang jia-Sheng Dong Li Wang Lang-Hong Lou jiangsu University of Technology Harbin Engineering University Institute of Metal Research Chinese Academy of Sciences

The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni–Mo–Cr–Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope and scanning electron microscope were employed for the microstructure observation, and X-ray diffraction, electron probe micro-analyzer, and transmission electron microscope were used for phase determination. It was found that the grain size increased and the volume fractions of initial M_6C carbides decreased along with the increase in solution treatment temperature. When tested at 650 °C/320 MPa, the stress rupture lives decreased with the increase in solution treatment temperature, but the stress rupture lives increased slightly at first and then decreased for the samples solution heat treated at 1220 °C when tested at 700 °C/240 MPa. The elongations showed the descendent trends under these two conditions. The stress rupture life and elongation for the aged samples all showed a noticeable improvement at 650 °C/320 MPa, but there was no noticeable improvement at 700 °C/240 MPa. The reasons can be attributed to the grain size, test conditions, and the initial and secondary carbides.

关键词： Corrosion-resistant superalloy Heat treatment Stress rupture properties Secondary carbides

Pressure infiltration of molten aluminum for densification of environmental barrier coatings

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Journal of Advanced Ceramics 2022年第1期11卷 145-157页

作者： Lin DONG Mei-jun LIU Xiao-Feng ZHANG Xue-Shi ZHUO jia-Feng FAN Guan-jun YANG Ke-song ZHOU State Key Laboratory for Mechanical Behavior ofMaterials School ofMaterials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for Modern Materials Surface Engineering Technology Institute of New MaterialsGuangdong Academy of ScienceGuangzhou 510650China

Environmental barrier coatings(EBCs)effectively protect the ceramic matrix composites(CMCs)from harsh engine environments,especially steam and molten ***,open pores inevitably formed during the deposition process provide the transport channels for oxidants and corrosives,and lead to premature failure of *** research work proposed a method of pressure infiltration densification which blocked these open pores in the *** results showed that it was difficult for aluminum to infiltrate spontaneously,but with the increase of external gas pressure and internal vacuum simultaneously,the molten aluminum obviously moved forward,and finally stopped infiltrating at a depth of a specific *** on the wrinkled zigzag pore model,a mathematical relationship between the critical pressure with the infiltration depth and the pore intrinsic geometry was *** infiltration results confirmed this relationship,indicating that for a given coating,a dense thick film can be obtained by adjusting the internal and external gas pressures to drive a melt infiltration.

关键词： infiltration process channel pore densification pressure assistant environmental barrier coating(EBC)

Optimal Time Decay of Navier–Stokes Equations with Low Regularity Initial Data

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Acta Mathematica Sinica,English Series 2018年第5期34卷 855-872页

作者： jun Xiong jia Department of Mathematics Xi’an Jiaotong University Beijing Center for Mathematics and Information Interdisciplinary Sciences (BCMIIS)

In this paper, we study the optimal time decay rate of isentropic Navier-Stokes equations under the low regularity assumptions about initial data. In the previous works about optimal time decay rate, the initial data need to be small in H^[N/2]＋2（R^N）. Our work combined negative Besov space estimates and the conventional energy estimates in Besov space framework which is developed by Danchim Through our methods, we can get optimal time decay rate with initial data just small in B^N/2-1,N/2＋1∩^N/2-1,N/2 and belong to some negative Besov space （need not to be small）. Finally, combining the recent results in [25] with our methods, we only need the initial data to be small in homogeneous Besov space B^N/2-2,N/2 ∩B^N/2-1 to get the optimal time decay rate in space L2.

关键词： Compressible fluids besov space framework optimal time decay negative Besov space

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun jia Qi-lin Ma Yu Hou Ba Li He-song Zhang Qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

Microstructure and wear behaviors of TiB/TiC reinforced Ti2Ni/α(Ti) matrix coating produced by laser cladding

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Rare Metals 2020年第3期39卷 304-315页

作者： Jin-Zhong Shao jun Li Rui song Lv-Lin Bai jia-Li Chen Cui-Cui Qu School of Materials Engineering Shanghai University of Engineering ScienceShanghai201620China

A Ti2Ni/a(Ti)matrix composite coating reinforced by TiC and TiB was prepared on a Ti6A14V substrate by laser *** microstructure of the coating was examined and *** wear behavior of the coating at various sliding speeds was investigated from the perspective of energy dissipation,and the relationship between accumulated dissipated energy(ΣE)and accumulated wear volume(ΣV)was *** indicate a good linear relationship betweenΣE andΣV at low sliding speed(0.1 m·s-1);at higher sliding speed(0.2 m·s-1),the relationship between these parameters follows a quadratic *** results may be explained from the perspective of energy transformation,wherein the friction heat and plastic deformation of the coating surface consume a substantial amount ofΣE at high sliding speed(0.2 m·s-1)and the remainder of the energy is used to produce worn coating *** wear mechanism of the coating involves a combination of microcutting and brittle debonding accompanied by oxidization of the worn surface and formation of Al2O3 adherents.

关键词： Wear behaviors Coating Laser cladding Accumulated dissipated energy

Correlation between indoor and outdoor corrosion tests for coal train body steel in a coal medium environment

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Journal of Iron and Steel Research International 2022年第9期29卷 1495-1504页

作者： jia-liang song jun-hang Chen Pan Yi Na-na Chen Zhao-liang Li Kui Xiao Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center University of Science and Technology BeijingBeijing 100083China China Electric Power Research Institute Beijing 100192China

Q345B carbon steel as well as Q450NQR1 and S500AW weathering steels were subjected to outdoor exposure corrosion tests in coal environments and indoor periodic immersion accelerated corrosion tests with a simulated coal leaching *** corrosion kinetics were studied by the weight loss method,and the corrosion morphology and corrosion product composition were observed and analyzed by scanning electron microscopy,energy-dispersive spectroscopy and X-ray ***,correlation analysis of the indoor and outdoor tests was carried out by the gray correlation analysis *** results show that the relationship between the corrosion weight loss and corrosion time of the three steels conforms to follow the exponent power *** particular,Q450NQR1 steel has the best corrosion *** types of corrosion products and the distribution of elements in the rust layer of the three steels are similar in the indoor and outdoor *** gray correlation degrees of the three steels in the indoor and outdoor tests are all greater than 0.6;thus,the two corrosion tests have a good *** on this,the accelerated simulation test method of the coal leaching solution is determined,and life prediction models of three steels in coal leaching solution are established to simulate the corrosion of the bottom board and side board.

关键词： Coal train body steel Coal environment-Corrosion Outdoor exposure test Indoor acceleration test Correlation

Legacy of herbicides in water from Hailun City,Northeast China:Occurrence,source,and ecological risk assessment

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Journal of Environmental Sciences 2024年第11期145卷 50-63页

作者： jun Ma Wenjie Ren Hongzhe Wang jiayin song junfeng jia Hong Chen Changyin Tan Ying Teng School of Geographic Sciences Hunan Normal UniversityChangsha 410081China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China College of Materials and Chemistry Tongren UniversityTongren 554300China

Herbicides(HBCs)are extensively used in modern ***,their potential negative impacts on environmental media have emerged as a significant environmental *** this study,we employed positivematrix factorization(PMF)to identify the potential sources of ***,we utilized amulti-matrix ecological riskmodel to assess the risks associated with HBCs in both surface water and groundwater in the black soil region of Northeast *** findings revealed that the levels of15HBCs in surface water and groundwater ranged from585.84 to 6466.96 ng/L and 4.80 to 11,774.64 ng/L,*** PMF results indicated that surface runoff and erosion accounted for 50%of the total HBCs in water,serving as the primary *** tested HBCs exhibited acute risk values within acceptable *** risk index for the∑15HBCs was categorized as“moderate risk”in 31%of the surface waters and 13%of the ***,4%of the groundwater sampling sites reached the“high risk”*** chronic risk quotient of∑15HBCs in surface water and groundwater was 92%and 62%at the“high risk”level,***,noncarcinogenic HBCs contributed more significantly to the ecotoxicology of the aquatic system than carcinogenic *** study provides comprehensive information on the legacy of HBCs in water bodies and emphasizes the potential risks posed by HBCs to aquatic *** results obtained from this study could help relevant management authorities in developing and implementing effective regulations tomitigate the ecological and environmental risks associated with HBCs.

关键词： Herbicide Surface and groundwater Source apportionment Ecological risk assessment

Review of the Low-Lying Excited Baryons ∑^(*)(1/2^(-))

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Chinese Physics Letters 2024年第10期41卷 31-37页

作者： En Wang Li-Sheng Geng jia-jun Wu Ju-jun Xie Bing-song Zou School of Physics Zhengzhou UniversityZhengzhou 450001China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China School of Physics Beihang UniversityBeijing 102206China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 102206China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China School of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 101408China Department of Physics Tsinghua UniversityBeijing 100084China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

Strong empirical and phenomenological indications exist for large sea-quark admixtures in the low-lying excited *** the low-lying excited baryon ∑^(*)(1/2^(-))is important for determining the nature of the low-lying ... 详细信息

关键词： excited quark determining

Photothermal probiotics delivery of photodynamic agents for enhanced immunogenic cell death within hypoxia center of solid tumors

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Nano Research 2025年第1期18卷 642-652页

作者： Wen Luo Shiyu Du Yateng jiang Bangshun He jun Tang Jingjing Yang Yujun song jiangsu Key Laboratory of Artificial Functional Materials State Key Laboratory of Analytical Chemistry for Life ScienceNational Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210023China Department of Laboratory Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006China Department of Anesthesiology Jinling HospitalMedical School of Nanjing UniversityNanjing 210000China Department of Biochemistry and Molecular Biology School of Medicine&Holistic Integrative MedicineJiangsu Collaborative Innovation Center of Chinese Medicinal Resources IndustrializationNanjing University of Chinese MedicineNanjing 210023China

Resulting from harsh hypoxic environmental conditions,central cells in the core of solid tumors are usually more aggressive and malignant with a less stable ***,therapeutic agents with improved penetration for the activation of immunity in tumor centers exhibit promising potential in ***,polydopamine-coated Escherichia coli Nissle 1917(EcN)bearing chlorin e6(Ce6)-loaded and polyethyleneimine(PEI)-coated hollow manganese dioxide(shorted as EP-ChP)are applied for enhanced immunotherapy in deep *** accumulation in tumor center through hypoxia targeting,manganese dioxide is degradated under the tumor microenvironment with released Ce6 and thus generates reactive oxygen species(ROS)upon 660 nm laser irradiation,which can further lower thermalresistance of cancer cells via HSP90α*** to that,heating induced by polydopamine upon 808 nm laser irradiation can achieve effective tumor *** upon dual laser induces enhanced immunogenic cell death,while bacterial infections in tumor tissues also trigger innate *** bacteria-based approach provides enhanced antitumor immune responses in deep tumors with great potential in the reshaping of immunosuppression tumor microenvironment.

关键词： bacteria phototherapies immunotherapy hypoxia targeting tumor penetration

基于指数滤波模型的青藏高原根系层土壤水分估算研究

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高原气象 2025年第1期44卷 134-149页

作者：宋雨曦苏建宾文军郑东海成都信息工程大学大气科学学院高原大气与环境四川省重点实验室四川成都610225 中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室国家青藏高原科学数据中心北京100101

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河... 详细信息

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河上游、玛曲)数据,本文系统评估了指数滤波模型在青藏高原不同气候与下垫面区域估算根系层(10 cm/20 cm/40 cm)土壤水分的适用性,探讨了不同环境因素(土壤、气候、植被)对模型特征时长参数T值的影响,最后评估了利用三种方法(各观测网络或青藏高原站点最优T值(Topt)中位数、随机森林模型)获取的区域T值估算青藏高原根系层土壤水分的可靠性。研究发现:(1)随着土壤深度的增加,根系层与表层土壤水分的相关性降低,而其空间异质性增大,导致指数滤波模型的应用精度降低,而模型T值及其空间异质性增大;(2)空间上随着降水量和土壤含水量的增加,根系层与表层土壤水分的相关性增大,而其空间异质性降低,使得指数滤波模型的应用精度上升,而其在区域内不同站点应用精度的差异呈现降低趋势;(3)土壤性质尤其是砂土含量是控制青藏高原区域T值空间分布的主要因素;(4)T值的获取对指数滤波模型在青藏高原的应用精度影响较小,当前常用的区域Topt中位数和随机森林模型均能获取相对合理的区域T值和取得一致且相对准确的模拟结果。本研究的发现有望推动利用指数滤波模型基于卫星表层土壤水分资料准确获取青藏高原根系层土壤水分。

关键词：青藏高原指数滤波模型根系层土壤水分不同气候与下垫面区域

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