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Influence of Solid Particles Deposition on the Initial Atmospheric Corrosion of 7b04 Aluminum Alloy

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SSRN 2022年

作者： Gao, Meng Sun, Zhihua Yan, Wei Tang, Zhihua Zhang, Yunan Aviation Key Laboratory of Science and Technology on Advanced Corrosion and Protection for Aviation Material Beijing Aero Engine Corporation of China Beijing Institute of Aeronautical Materials Beijing100095 China National Center for Materials Service Safety University of Science and Technology Beijing Beijing100083 China

The influence of the deposition of three different particles (NaCl, C and SiO2) on the initial atmospheric corrosion of 7B04 aluminum alloy was investigated via laboratory exposure testing, environmental scanning electron microscope (E-SEM), energy dispersive X-ray spectroscopy (EDS), and scanning Kelvin probe (SKP). The results showed that the deposition of NaCl had a significant acceleration effect on the initial corrosion of 7B04 aluminum alloy and resulted in the occurrence of localized corrosion on sample surface. Because of its capillary condensation effect, SiO2 could absorb the vapor in humid environment to form a local water-rich area around the particles which could promote the corrosion of 7B04 aluminum alloy. C had basically no effect on the corrosion of 7B04 aluminum alloy. © 2022, The Authors. All rights reserved.

关键词： Aluminum alloys

Nucleation and Growth of Graphene at Different Temperatures by Plasma Enhanced Chemical Vapor Deposition

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SSRN 2023年

作者： Li, Na Li, Di Zhen, Zhen Zhang, Rujing Mu, Rende Xu, Zhenhua He, Limin Key Laboratory of Advanced Corrosion and Protection for Aviation Materials Beijing Institute of Aeronautical Materials Aero Engine Corporation of China Beijing10095 China Beijing Institute Of Graphene Technology China Xinjiang Petrochina Construction and Installation Engineering Co. Ltd China

Temperature plays an important role in the synthesis of graphene by chemical vapor deposition. In the low-temperature plasma-enhanced chemical vapor deposition (PECVD) process, although the decomposion of hydrocarbon precursor no longer depends on growth temperature, which can affect the nucleation and growth of graphene through the influence of free radical diffusion and adsorption, metal substrate catalytic ability and other factors, and ultimately lead to the difference in the growth quality of graphene. In this paper, the differences of graphene nucleation and growth at different temperatures were studied. We noted that the nucleation and growth of graphene varied greatly in different temperature zones. Graphene could not be grown at low temperatures ( 950 ℃), the coexistence of large and small grains was finally formed. Ultimately, the models of graphene nucleation and growth in different temperature zones were proposed. © 2023, The Authors. All rights reserved.

关键词： Nucleation

Influence of Assembly Parameters on Tensile Behavior of Hybrid CMC and Superalloy Bolted Joints by Progressive Damage Analysis

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Journal of Harbin Institute of technology(New Series) 2021年第3期28卷 53-60页

作者： Chao Lv Feng Li Shuyuan Zhao Qian Sun Mingrui Li Xinyang Sun China Academy of Aerospace Aerodynamics Beijing 100074China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China Shenyang Aircraft Design and Research Institute Aviation Industry Corporation of ChinaShenyang 110000China School of Aeronautics and Astronautics Harbin Institute of TechnologyHarbin 150001China

With the considerable applications of ceramic matrix composites(CMC) in aircraft engineering, the design of CMC bolted joint gains paramount attention because of its capacity to to improve load-bearing efficiency of aircraft key structure. In this work, a 3 D finite element model was established to predict tensile performance and failure modes of single-lap, single-bolt 2 D C/SiC composite, and superalloy joint, which considers the progressive damage behavior of 2 D woven C/SiC composites. On the basis of the developed progressive damage model, a parametric study was carried out to illustrate the effects of bolt preload and bolt-hole clearance on mechanical behaviors of the hybrid bolted joint. It was found that the increase in the value of bolt preload made the failure load grow first and then drop, and the optimum value of bolt preload 5.00 kN generated 56.47% rise in the initial failure load and 22.83% rise in the final failure load for the bolted joint in comparison with zero preload case. As the clearance increased from 0 to 2.00%, the initial and final failure loads respectively declined by 45.88% and 24.02% for 2.00% bolt-hole clearance relative to the neat-fit case. The loss in failure loads can be reduced to compressive stress concentration around the fastening hole-edge area, leading to the appearance of earlier damages by the introduction of increasing bolt hole clearance.

关键词： ceramic matrix composite progressive damage analysis tensile performance bolt preload bolt-hole clearance

Uncovering the Risk Spillover of Agricultural Water Scarcity by Simultaneously Considering Water Quality and Quantity

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SSRN 2023年

作者： Li, Hui Chen, Qionghong Liu, Gengyuan Lombardi, Ginevra Virginia Su, Meirong Yang, Zhifeng State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing100875 China Advanced Interdisciplinary Institute of Environment and Ecology Beijing Normal University Zhuhai Campus Zhuhai519087 China Department of Economies and Management University of Firenze Via delle Pandette 9 Firenze50127 Italy Research Center for Eco-environmental Engineering Dongguan University of Technology Dongguan523808 China State Key Laboratory of Water Environmental Simulation China

Not only insufficient water quantity, but also inadequate water quality can pose constraints on agricultural production and result in potential economic losses. Such economic losses in agriculture may adversely impact downstream producers through reduced input supplies. In this study, we developed an index assessing potential economic losses in agriculture under both quantity- and quality-induced water scarcity, termed integrated Agricultural Water Scarcity Risk (AWSR). Combining integrated AWSR with a multi-regional input-output model, we estimated the spillovers of integrated AWSR along supply chains. Our results showed that the intersectoral transmission of virtual integrated AWSR (sectoral spillovers in terms of integrated AWSR) were 5 times the virtual quantity-based AWSR. Pollution significantly intensifies the indirect supply-chain repercussions of agricultural water scarcity. Moreover, we identified some primary virtual integrated AWSR exporters (e.g., Jiangsu-vegetables and Shandong-swine, of which the integrated AWSR had considerable spillover effects on downstream sectors) and importers (e.g., Henan-chemical industry and Henan-textiles, which were vulnerable to upstream integrated AWSR), that could not be detected in quantity-based AWSR results. This study underscores the importance of water quality in the assessments of AWSR. Strategies to mitigate the spillovers of AWSR might be inefficient without the consideration of water quality. © 2023, The Authors. All rights reserved.

关键词： Water quality

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碱金属离子诱导亚稳相钌纳米晶合成

Science Bulletin 2023年第23期68卷 2924-2928,M0004页

作者：张俊涛刘效知陈立刚曹茂丰李晓彤苏东胡志伟徐勇黄小青 State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage Devices Collaborative Innovation Center of Advanced Energy MaterialsSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China State Power Investment Corporation Hydrogen Energy Company Limited Beijing 102209China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Max Planck Institute for Chemical Physics of Solids Dresden 01187Germany

亚稳相金属纳米晶因其优异的物理化学性质备受关注,然而如何可控合成亚稳相结构依然面临诸多挑战.本文报道了碱金属离子诱导亚稳相钌纳米晶(面心立方相)的可控合成策略.研究表明钌纳米晶结构和碱金属离子半径密切相关,因此通过改变碱金... 详细信息

亚稳相金属纳米晶因其优异的物理化学性质备受关注,然而如何可控合成亚稳相结构依然面临诸多挑战.本文报道了碱金属离子诱导亚稳相钌纳米晶(面心立方相)的可控合成策略.研究表明钌纳米晶结构和碱金属离子半径密切相关,因此通过改变碱金属离子实现了面心立方相和六方密堆相比例的连续调控.理论计算结果表明,碱金属的存在导致面心立方相的形成能低于六方密堆相,并且这种能量差随着碱金属离子半径的增大而增大.本工作为拓展亚稳态结构的实际应用奠定了基础.

关键词：亚稳相碱金属离子面心立方纳米晶结构金属纳米晶物理化学性质可控合成钌

simulation of chiral motion of excitation within the ground-state manifolds of neutral atoms

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arXiv

arXiv 2024年

作者： Tang, Hao-Yuan Li, Xiao-Xuan You, Jia-Bin Shao, Xiao-Qiang Center for Quantum Sciences School of Physics Northeast Normal University Changchun130024 China Sino-European Institute of Aviation Engineering Civil Aviation University of China Tianjin300300 China 1 Fusionopolis Way Connexis 138632 Singapore Center for Advanced Optoelectronic Functional Materials Research Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education Northeast Normal University Changchun130024 China

Laser-induced gauge fields in neutral atoms serve as a means of mimicking the effects of a magnetic field, providing researchers with a platform to explore behaviors analogous to those observed in condensed matter systems under real magnetic fields. Here, we propose a method to generate chiral motion in atomic excitations within the neutral atomic ground-state manifolds. This is achieved through the application of polychromatic driving fields coupled to the ground-Rydberg transition, along with unconventional Rydberg pumping. The scheme offers the advantage of arbitrary adjustment of the effective magnetic flux by setting the relative phases between different external laser fields. Additionally, the effective interaction strength between the atomic ground states can be maintained at 10 kHz, surpassing the capabilities of the previous approach utilizing Floquet modulation. Notably, the proposed method can be readily extended to implement a hexagonal neutral atom lattice, serving as the fundamental unit in realizing the Haldane model. © 2024, CC BY.

关键词： Atoms

Separated Active Site and Reaction Space for Multi-Pollutant Elimination Significantly Enhancing Low Toxic Product Selectivity

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advanced Functional Materials 2023年第48期33卷

作者： Wei, Lu Liu, Yuxi Cui, Suping Wang, Can Hsi, Hsing-Cheng Duan, Erhong Peng, Yue Dai, Hongxing Guo, Guangsheng Deng, Jiguang Key Laboratory of Beijing on Regional Air Pollution Control Beijing Key Laboratory for Green Catalysis and Separation Center of Excellence for Environmental Safety and Biological Effects Beijing University of Technology Beijing100124 China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional Materials Ministry of Education Beijing University of Technology Beijing100124 China School of Environmental Science and Engineering Tianjin University Tianjin300350 China Graduate Institute of Environmental Engineering National Taiwan University Taipei10617 Taiwan School of Environmental Science and Engineering Hebei University of Science and Technology Hebei050018 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing100084 China

It is possible to remove volatile organic compounds containing chlorine (CVOCs, such as chlorobenzene) in a single device designed for selective catalytic reduction of NOx with NH3 for the industries containing CVOCs and NOx. Breaking the efficiency-selectivity trade-off in chlorobenzene oxidation remains a major challenge due to the conjugation of halogen atoms with the benzene ring and the reducing nature of NH3. A stepwise synthesis strategy is demontrated to disperse dual Ru/Cu Lewis acid sites outside and inside the zeolite channel. Under the confinement of zeolite, the Ru4+ Lewis acid site on the external surface of the zeolite promotes chlorobenzene oxidation by weakening the p-π conjugate structure of Cl and benzene ring, while the Cu2+ Lewis acid site within the internal channel converts NOx and NH3 to N2. The mutual interference between catalytic oxidation and reduction is successfully avoided. Therefore, the low toxic CO2 and HCl selectivity experience a considerable increase from 21% to 86%, and from 51% to 94% with 91% conversion of chlorobenzene, while maintaining excellent elimination performance for NO (with N2 selectivity exceeding 90%). The incorporation of separated active sites and reaction spaces into the design may offer potentials for other energy and environmental applications. © 2023 Wiley-VCH GmbH.

关键词： Zeolites

Application of smog chambers in atmospheric process studies

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National Science Review 2022年第2期9卷 126-141页

作者： Biwu Chu Tianzeng Chen Yongchun Liu Qingxin Ma Yujing Mu Yonghong Wang Jinzhu Ma Peng Zhang Jun Liu Chunshan Liu Huaqiao Gui Renzhi Hu Bo Hu Xinming Wang Yuesi Wang Jianguo Liu Pinhua Xie Jianmin Chen Qian Liu Jingkun Jiang Junhua Li Kebin He Wenqing Liu Guibin Jiang Jiming Hao Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing Convenient Environmental Tech Co.Ltd Key Laboratory of Environmental Optics and Technology Anhui Institutes of Optics and Fine Mechanics Chinese Academy of Sciences State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of Geochemistry Chinese Academy of Sciences Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and Engineering Fudan University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University

Smog chamber experimental systems,which have been widely used in laboratory simulation for studying atmospheric processes,are comprehensively reviewed in this *** components,development history,main research topics and main achievements of smog chambers are *** smog chambers in the world,including their volumes,wall materials,light sources and features,are summarized and *** factors of smog chambers and their influences on the simulation of the atmospheric environment are discussed,including wall loss,wall emission and background *** features of next-generation smog chambers and their application prospect in future studies of the atmospheric environment are also outlined in this paper.

关键词： smog chamber simulation wall effect secondary aerosol ozone

Effects of Wo3 and Moo3 Loadings on Vanadia-Based Catalysts for Nh3-Scr: Revealed by in Situ Infrared and Two-Dimensional Correlation Spectroscopy

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SSRN 2023年

作者： Lv, Zhihui He, Guangzhi Ge, Yanli Liu, Yongchun Yu, Yunbo He, Hong State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China University of Chinese Academy of Sciences Beijing100049 China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing Innovation Center for Engineering Science and Advanced Technology College of Environmental Science and Engineering Peking University Beijing100871 China Aerosol and Haze Laboratory Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing100029 China Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou341000 China Center for Excellence in Regional Atmospheric Environment Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiamen361021 China

Vanadia-based catalysts have been widely applied in NOx reduction, while the promoting effects of WO3 and MoO3 are still under debate. Herein, we prepared V2O5/TiO2, V2O5-WO3/TiO2, and V2O5-MoO3/TiO2 catalysts and revealed that WO3 and MoO3 enhanced the activity of V2O5/TiO2, especially under wet conditions. In situ DRIFTS, two-dimensional correlation spectroscopy (2D COS), and DFT calculations demonstrated that NH3 adsorbed on Lewis acid sites of V2O5/TiO2, resulting in the formation of NH3ads-L1 (1284 cm-1, Ti sites of O=V-O-Ti) and NH3ads-L2 (1604 cm-1, V=O sites). By using 2D COS, we found that the NH3ads-L1 exhibited higher reactivity towards NO to produce NH2NO* via NH2*, which was promoted by WO3. Moreover, WO3 and MoO3 doping inhibited H2O adsorption, and promoted its desorption by increasing temperature, thus protecting the V=O sites on V2O5/TiO2. Also, 2D COS provided a new perspective for in-depth understanding of the active sites and intermediates in the NH3-SCR reaction. © 2023, The Authors. All rights reserved.

关键词： Catalysts