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环境科学 2025年第1期46卷 603-612页

作者：张春杰陈速敏王敏燕姚震聂磊北京市生态环境保护科学研究院城市大气挥发性有机物污染防治技术与应用北京市重点实验室北京100037

为分析北京市农药使用源VOCs排放特征,通过现场调研获取了北京市常用农药使用种类及剂型分布,采用实验室检测的方法对不同剂型农药VOCs含量进行了检测,建立北京市本地化分剂型的农药VOCs排放因子,编制了农药使用源VOCs排放清单,分析了... 详细信息

为分析北京市农药使用源VOCs排放特征,通过现场调研获取了北京市常用农药使用种类及剂型分布,采用实验室检测的方法对不同剂型农药VOCs含量进行了检测,建立北京市本地化分剂型的农药VOCs排放因子,编制了农药使用源VOCs排放清单,分析了农药使用源VOCs的时空分布特征.结果表明:①农药剂型是影响农药VOCs排放的主要因素,核算农药使用源VOCs排放量时,不仅要了解目标区域农药种类和有效成分,也要同步获取农药剂型信息.②北京市不同剂型农药本地化排放因子由高到低依次为乳油剂(839 g·kg^(−1))、可溶液剂(715 g·kg^(−1))、水乳剂(659 g·kg^(−1))、微乳剂(371 g·kg^(−1))、悬浮剂(121 g·kg^(−1))、可湿性粉剂(34 g·kg^(−1))、水分散粒剂(30 g·kg^(−1))和水剂(17 g·kg^(−1)).③2020年北京市农药使用量及农药使用源VOCs排放量分别为2990 t和757 t.其中,杀菌剂的农药使用量最大,占总量的54.3%,但其VOCs排放量仅占6.5%;杀虫剂农药使用量占比34.8%,其VOCs排放量为84.1%.不同作物类型中,果树类VOCs排放量较高,其中杂果最高,占比为48.1%.④在空间分布上,VOCs排放较高的区域为生态涵养发展区(70.5%)和城市发展新区(24.4%),平谷区VOCs排放量最大,密云区和房山区次之,分别占总量的30.7%、11.8%和8.9%.生态涵养发展区贡献较高的作物为果树类、玉米、薯类和豆类等;城市发展新区贡献较高的作物为蔬菜、小麦和瓜类等作物.在时间分布上,夏季和春季是农药使用源VOCs排放的高峰期,分别占总量的45.2%和33.8%.

关键词：农药使用源挥发性有机物(VOCs) 本地化排放因子排放清单时空分布

Crystal plasticity model to predict fatigue crack nucleation based on the phase transformation theory

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Acta Mechanica Sinica 2019年第5期35卷 1033-1043页

作者： Lu Liu Jundong Wang Tao Zeng yao yao School of Mechanics Civil Engineering and ArchitectureNorthwestern PolytechnicalUniversityXi'an 710072China Max-Planck-Institut für Eisenforschung GmbH Max Planck Str.140237 DüsseldorfGermany

A crystal plasticity model is developed to predict the fatigue crack nucleation of polycrystalline materials,in which the accumulated dislocation dipoles are considered to be the origin of *** describe the overall softening behavior under cyclic loading,a slip system-level dislocation density-related damage model is proposed and implemented in the finite element analysis with Voronoi *** numerical model is applied to calibrate the stress-strain relationship at different cycles before fatigue crack *** parameters determined from the numerical analysis are substituted into a modified phase transformation model to predict the critical fatigue crack nucleation *** with the experimental results of Sn-3.0Ag-0.5Cu(SAC305)alloy and P91 steel,the proposed method can describe the constitutive behavior and predict the fatigue crack nucleation accurately.

关键词： Fatigue crack nucleation Damage Crystal plasticity Finite element Dislocation density

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新时代乡村教师“教得好”的专业发展探究

安阳师范学院学报 2025年第1期27卷 130-134页

作者：姚远峰安阳师范学院

当前，乡村教师“教不好”是制约乡村教师专业发展的瓶颈之一。乡村教师“教不好”主要原因在于针对乡村教师“教得好”的培训不够精准到位，因此需要重新审视和构建新时代乡村教师“教得好”培训的理论依据、方案设计和支持服务。在理... 详细信息

当前，乡村教师“教不好”是制约乡村教师专业发展的瓶颈之一。乡村教师“教不好”主要原因在于针对乡村教师“教得好”的培训不够精准到位，因此需要重新审视和构建新时代乡村教师“教得好”培训的理论依据、方案设计和支持服务。在理论依据上，要引入区域治理理论和学习共同体理论，促进乡村教师专业发展由个体向群体发展的有机融合、由单一学校向区域联动推进的有机结合转变；在方案设计上，要充分考虑乡村教师的需求和特点，构建以胜任力为核心的“一个信仰、六项技能”培训框架；在支持服务上，要实施区域联动的研训赛一体化模式、聚焦“说读写讲管”五位一体技能训练、加强专业导航和行政护航的两翼支持。

关键词：新时代乡村教师 “教得好”

Characteristics and applications of interplanetary coronal mass ejection composition

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Science China(Technological Sciences) 2020年第11期63卷 2171-2187页

作者： SONG HongQiang yao Shuo Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China School of Geophysics and Information Technology China University of Geosciences(Beijing)Beijing 100083China

In situ measurements of interplanetary coronal mass ejection(ICME)composition,including elemental abundances and charge states of heavy ions,open a new avenue to study coronal mass ejections(CMEs)besides remote-sensing *** ratios between different elemental abundances can diagnose the plasma origin of CMEs(e.g.,from the corona or chromosphere/photosphere)due to the first ionization potential(FIP)effect,which means elements with different FIPs get fractionated between the photosphere and *** ratios between different charge states of a specific element can provide the electron temperature of CMEs in the corona due to the freeze-in effect,which can be used to investigate their eruption *** this review,we first give an overview of the ICME composition and then demonstrate their applications in investigating some important subjects related to CMEs,such as the origin of filament plasma and the eruption process of magnetic flux ***,we point out several important questions that should be addressed further for better utilizing the ICME composition to study CMEs.

关键词： coronal mass ejection interplanetary coronal mass ejection elemental abundance ionic charge state magnetic flux rope magnetic cloud filament flare

The effect of oxygen concentration on the coupled neurons:Rich spiking patterns and synchronization

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Science China(Technological Sciences) 2020年第11期63卷 2339-2348页

作者： HE ZhiWei yao ChengGui Department of Mathematics Shaoxing UniversityShaoxing 312000China College of Mathematics Physics and Information EngineeringJiaxing UniversityJiaxing 314000China

The dynamical microenvironments play a crucial role in neuronal spiking *** this paper,we investigated the effect of oxygen concentration on different synchronous spiking patterns of two coupled neuron models by including dynamical ion *** coupling modes of electrical diffusive coupling and potassium diffusive coupling were *** these two cases,oxygen concentration exhibited an important role in the synchronous spiking patterns between two coupled neurons,and extremely rich electrical activities were *** the potassium diffusive coupling,differential synchronous patterns of oscillation state(OS),synchronous epileptic seizure state(SSZ)and synchronous spreading depression state(SSD)as well as SZ and SD bursting states were *** the electrical diffusive coupling,differential synchronous patterns of resting state(RS),SSZ and SSD were observed.

关键词： neuron model phase synchronization electrical diffusive coupling potassium diffusive coupling

Blockade of Arf1-mediated lipid metabolism in cancers promotes tumor infiltration of cytotoxic T cells via the LPE-PPARγ-NF-κB-CCL5 pathway

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Life Metabolism 2023年第5期2卷 25-37页

作者： Na Wang Tiange yao Chenfei Luo Ling Sun yuetong Wang Steven x.Hou Department of Cell and Developmental Biology at School of Life Sciences State Key Laboratory of Genetic EngineeringInstitute of Metabolism and Integrative BiologyHuman Phenome InstituteFudan UniversityShanghai 200438China

Tumor immunotherapy has achieved breakthroughs in a variety of tumors. However, the systemic absence of T cells in tumors and immunosuppressive tumor microenvironment so far limits the efficacy of immunotherapy to a small population of patients. Therefore, novel agents to increase T-cell tumor infiltration are urgently needed in the clinic. We recently found that inhibition of the ADP-ribosylation factor 1 (Arf1)-mediated lipid metabolism not only kills cancer stem cells (CSCs) but also elicits an anti-tumor immune response. In this study, we revealed a mechanism that targeting Arf1 promotes the infiltration of cytotoxic T lymphocytes (CTLs) into tumors through the C-C chemokine ligand 5 (CCL5)- C-C chemokine receptor type 5 (CCR5) pathway. We found that blockage of Arf1 induces the production of the unsaturated fatty acid (PE 18:1) that binds and sequestrates peroxisome proliferator- activated receptor-γ (PPARγ) from the PPARγ-nuclear factor-κB (NF-κB) cytoplasmic complex. The released NF-κB was then phospho-rylated and translocated into the nucleus to regulate the transcription of chemokine CCL5. CCL5 promoted infiltration of CTLs for tumor regression. Furthermore, the combination of the Arf1 inhibitor and programmed cell death protein 1 (PD-1) blockade induced an even stronger anti-tumor immunity. Therefore, targeting Arf1 represents a novel anti-tumor immune approach by provoking T-cell tumor infiltration and may provide a new strategy for tumor immunotherapy.

关键词： immune checkpoint blockade cancer stem cells cytotoxic T cells PPARγ CCL5-CCR5 pathway Arf1

Preparation and thermal stability of Pd_(40.5)Ni_(40.5)Si_xP_(19-x) bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 204-207页

作者： yang Li yao-cen Wang Ke-fu yao Department of Mechanical Engineering Tsinghua University Beijing 100084 China

With the addition of Si to replace some P,Pd40.5Ni40.5SixP19-x（x=0,2.5,5,9.5,14,and 19 in atomic number fraction） bulk glassy samples with the diameter of about 5 mm were successfully prepared by use of flux treatment and water quenching *** the increase of Si content,the glass forming ability of Pd40.5Ni40.5Si-xP19-x increases first for low Si content and then decreases for high Si content （Si≥9.5at%）.The Pd40.50Ni40.5Si5P14 glassy alloy possesses the largest supercooled liquid region△T of 119 K,the largest reduced glass transition temperature of 0.621,and the largestγparameter of 0.460,indicating that this glassy alloy possesses very large glass forming ability and very high thermal stability.

关键词： bulk metallic glass flux method glass forming ability water quenching thermal stability

Non-Steady Equilibrium during Pro-Eutectoid Ferrite Formation in Fe-0.2C Alloy

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Journal of Iron and Steel Research International 2002年第2期9卷 28-32页

作者： ZHANG Hong-bing WU Rui-heng HSU T y(xU Zu-yao) RUAN xue-yu Shanghai Institute of Technology Shanghai Jiaotong University

As rolled microstructure and mechanical properties of a new kind of grain boundary allotriomorphic ferrite/granular bainite duplex steel plate and its crack propagation behavior were investigated in comparison with simple granular bainitic steel plate. These new duplex plate steels possess better combination of strength and toughness than granular bainite plate steels under the conditions of conventional rolling and air cooling. The observation of fatigue crack propagation behaviors showed that the existence of proper grain boundary allotriomorphic ferrite increases the compatible deformation ability of duplex microstructure and leads to the formation of crack branching and curving route, and it has an evidently blunting effect on microcrack tip and results in higher impact toughness. In addition, the new duplex steel plate also has good weldability as hot rolled high strength low alloy structural steel.

关键词： duplex microstructure grain boundary allotriomorphic ferrite granular bainite high strength steel weldability

Electronic structure of correlated topological insulator candidate ybB6 studied by photoemission and quantum oscillation

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Chinese Physics B 2020年第1期29卷 70-75页

作者： T Zhang G Li S C Sun N Qin L Kang S H yao H M Weng S K Mo L Li Z K Liu L x yang y L Chen State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Department of Physics University of MichiganAnn ArborMI 48109USA Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China National Laboratory of Solid State Microstructures&Department of Materials Science and Engineering Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Quantum Matter BeijingChina Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Topological Quantum Computation Beijing 100190China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA School of Physical Science and Technology ShanghaiTech University and CAS-Shanghai Science Research CenterShanghai 201210China ShanghaiTech Laboratory for Topological Physics Shanghai 200031China Frontier Science Center for Quantum Information Beijing 100084China Department of Physics Clarendon LaboratoryUniversity of Oxford Parks RoadOxford OX13PUUK

Angle-resolved photoemission spectroscopy(ARPES)and torque magnetometry(TM)measurements have been carried out to study the electronic structures of a correlated topological insulator(TI)candidate yb *** observed clear surface states on the[001]surface centered at theГ^- and М^- points of the surface Brillouin ***,the fermiology revealed by the quantum oscillation of TM measurements agrees excellently with ARPES ***,the band structures we observed suggest that the band inversion in yb B6 happens between the yb5 dand B2bands,instead of the yb5dand yb4fbands as suggested by previous theoretical investigation,which will help settle the heavy debate regarding the topological nature of samarium/ytterbium hexaborides.

关键词： topological insulator electronic structure surface states