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Microstructure and properties of the interlayer heat-affected zone in X80 pipeline girth welds

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Progress in Natural Science:Materials International 2020年第1期30卷 110-117页

作者： fang Bai Hongsheng ding Lige Tong Liqing Pan School of Mathematics and Physics University of Science and Technology Beijing Pipeline Institute China Petroleum Pipeline Engineering Co.Ltd. School of Energy and Environmental Engineering University of Science and Technology Beijing College of Science China Three Gorges University

The heat-affected zone between the layers of a weld metal is a sensitive and important component of girth welds in X80 ***,only a few studies have focused on the interlayer heat-afected zone(IHAZ).In this work,thermal simulation was conducted to investigate the relationship between IHAZ microstructure and *** showed that the toughness of the weld metal improved after a single welding thermal cycle but decreased after double welding thermal cycles,particularly when the weld metal was subjected to unaltered coarse grains of *** relationship between the microstructure and properties of IHAZ was established to present the correlation of toughness with granular bainite content,grain size,and high-angle grain boundary content.

关键词： Girth weld Interlayer heat-affected zone Thermal simulation Granular bainite Toughness

Recent advances in synthesis of organosilicons via radical strategies

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Chinese Chemical Letters 2021年第4期32卷 1280-1292页

作者： Xueping Zhang Jingkun fang Chun cai Guoping Lu School of Chemical Engineering Nanjing University of ScienceTechnologyNanjing 210094China

Organosilicon compounds play an important role in the fields of materials science,pharmacy,and organic *** development of effective approaches for the preparation of these compounds have also become a research focus in organic *** recent years,free radical synthesis of organosilicons has been vigorously developed,which generally has the advantages of milder synthesis conditions,higher yields and selectivity,and free of precious metal catalysts compared with traditional *** article reviews research progresses in the synthesis of organosilico n compounds by free radical pathways since *** most cases,the radical silylation is achieved based on the reaction of silyl radicals,which are triggered by four routes including peroxide,transition-metal-induced peroxide decomposition,alkali,*** alkyl radicals can also initiate the radical silylation for the generation of C(sp^(3))—Si bonds.

关键词： Organosilicon Radical silylation Single electron transfer Hydrogen atom transfer Photoredox Alkyl radical

Spatiotemporal Characteristics and Future Scenario Simulation of the Trade-offs and Synergies of Mountain Ecosystem Services: A Case Study of the Dabie Mountains Area, China

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Chinese Geographical Science 2023年第1期33卷 144-160页

作者： fang Lin LIU Yanxiao LI Canfeng cai Jun School of Economics and Management Anhui Agriculture UniversityHefei 230036China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Kunming Comprehensive Survey Center of Natural Resources China Geological SurveyKunming 650100China

Mountain ecosystems play an essential role in supporting regional sustainable development and improving local ecological environments. However, economic development in mountainous areas has long been lagging, and multiple conflicts related to resource assurance, ecological protection, and economic development have emerged. An accurate grasp of the current status and evolutionary trends of mountain ecosystems is essential to enhance the overall benefits of ecosystem services and maintain regional ecological security. Based on the In VEST(Integrated Valuation of Ecosystem Services and Trade-offs) model, this study analyzed the spatiotemporal evolution patterns and the trade-offs and synergies among ecosystem services(ES) in the Dabie Mountains Area(DMA) of eastern China. The Markov-PLUS(Patch-generating Land Use Simulation) model was used to conduct a multi-scenario simulation of the area's future development. Water yield(WY) and soil conservation(SC) had overall increasing trends during 2000-2020, carbon storage(CS)decreased overall but slowed with time, and habitat quality(HQ) increased and then decreased. The ecological protection scenario is the best scenario for improving ES in the DMA by 2030;compared to 2020, the total WY would decrease by 3.77 × 10^(8) m^(3), SC would increase by 0.65 × 10^(6) t, CS would increase by 1.33 × 10^(6) t, and HQ would increase by 0.06%. The comprehensive development scenario is the second-most effective scenario for ecological improvement, while the natural development scenario did not have a significant effect. However, as the comprehensive development scenario considers both environmental protection and economic development, which are both vital for the sustainable development of the mountainous areas, this scenario is considered the most suitable path for future development. There are trade-offs between WY, CS, and HQ, while there are synergies between SC, CS, and HQ. Spatially, the DMA's central core district is the main strong

关键词： ecosystem services trade-offs InVEST(Integrated Valuation of Ecosystem Services and Trade-offs)model PLUS(Patchgenerating Land Use Simulation)model scenario projection Dabie Mountains China

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Seed-assisted growth for high-performance perovskite solar cells:A review

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Journal of Energy Chemistry 2024年第9期96卷 588-610页

作者： Zhimin fang Ting Nie Jianning ding Shengzhong(Frank)Liu Institute of Technology for Carbon Neutralization Yangzhou UniversityYangzhou 225127JiangsuChina Dalian National Laboratory for Clean Energy iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina

The rapid increase in the power conversion efficiency(PCE)of perovskite solar cells(PSCs)is closely related to the development of deposition techinique for perovskite *** high-quality perovskite film enables efficient charge transportation and less trap states,which are eventually translated into enhanced device ***-assisted growth(SAG)is a potential technique for depositing highly-crystallized perovskite films with preferential crystal orientation among the numerous approaches related to crystallization *** this review,we summarize the recent advances in the SAG technique for both one-step and two-step processed perovskite ***,seeding at the buried interface and on the top surface are also *** present different seeds and their corresponding seeding mechanism in detail,such as inorganic nanomaterials,organic ammoniums,alkali metal halides,and perovskite ***,challenges and perspectives are proposed to investigate the potential expansion of seeding engineering in high-performance PSCs,particularly large-area devices.

关键词： Perovskite solar cell Seed Crystallization Efficiency

Influence of the coupled-dipoles on photosynthetic performance in a photosynthetic quantum heat engine

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Chinese Physics B 2021年第4期30卷 299-304页

作者： Ling-fang Li Shun-cai Zhao Department of Physics Kunming University of Science and TechnologyKunming 650500China

Recent evidence suggests that the multiple charge-separation pathways can contribute to photosynthetic *** this work,the influence of coupled-dipoles on photosynthetic performance was investigated in a two-charge separation pathways quantum heat engine(QHE) *** the population dynamics of the two coupled sites,j-V characteristics,and power involving this photosynthetic QHE model were evaluated for the photosynthetic *** results illustrate that the photosynthetic performance can be greatly enhanced but quantum interference is deactivated by the coupleddipoles between the two-charge separation ***,the photosynthetic performance can also be promoted by the deactivated quantum interference owing to the *** is a novel role of the coupled-dipoles in the energy transport process of biological photosynthetic,and some artificial strategies may be motivated by this photosynthetic QHE model in the future.

关键词： photosynthetic performance coupled-dipole photosynthetic heat engine

A multi-mode multi-skill project scheduling reformulation for reconnaissance mission planning

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Science China(Information Sciences) 2022年第6期65卷 267-268页

作者： Junqi cai Zhihong PENG Sijian LIAO Shuxin ding School of Automation Beijing Institute of Technology Signal and Communication Research Institute China Academy of Railway Sciences Corporation Limited

Dear editor,Planning multi-agents scheduling to conduct reconnaissance missions is the core of reconnaissance decision support system. A reconnaissance mission comprises several tasks and a network representing precedence relationships between them, where each task represents an area in which the agents perform information gathering.

关键词： reconnaissance RCPSP multi-mode multi-skill scheduling multi agent system

The dynamic change of pore structure for low-rank coal under refined upgrading pretreatment temperatures

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Petroleum Science 2021年第2期18卷 430-443页

作者： Teng Li cai-fang Wu Zi-Wei Wang College of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065ShaanxiChina Shandong Key Laboratory of Depositional Mineralization and Sedimentary Mineral Shandong University of Science and TechnologyQingdao266590ShandongChina Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil and Gas Reservoirs Xi’an Shiyou UniversityXi’an710065ShaanxiChina School of Resources and Geosciences China University of Mining and TechnologyXuzhou221008JiangsuChina

Pore structure characteristics are significant factor in the evaluation of the physical characteristics of low-rank *** this study,three low-rank coal samples were collected from the Xishanyao Formation,Santanghu Basin,and low-temperature liquid-nitrogen adsorption(LP-N2A)measurements were taken under various pretreatment *** to the continuous loss of water and volatile matter in low-rank coal,the total pore volume assumes a three-step profile with knee temperatures of 150°C and 240°***,the ash in the coal can protect the coal *** collapse mainly occurs for mesopores with aperture smaller than 20 *** with apertures smaller than 5 nm exhibit a continuous decrease in pore volume,whereas the pore volume of mesopores with apertures ranging from 5 to 10 nm increases at lower pretreatment temperatures(<150°C)followed by a faint *** for mesopores with apertures larger than 10 nm,the pore volume increases significantly when the pretreatment temperature reaches 300°*** pore structure of low-rank coal features a significant heating effect,the pretreatment temperature should not exceed 150°C when the LP-N2A is used to evaluate the pore structure of low-rank coal to effectively evaluate the reservoir characteristics of low-rank coal.

关键词： Low-rank coal Low-temperature liquid-nitrogen adsorption Pore structure Refined upgrading temperatures Heating effect

Why Does Extreme Rainfall Occur in Central China during the Summer of 2020 after a Weak El Niño?

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Advances in Atmospheric Sciences 2021年第12期38卷 2067-2081页

作者： Congxi fang Yu LIU Qiufang cai Huiming SONG The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China CAS Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an710061China Laboratory for Ocean Dynamics and Climate Pilot Qingdao National Laboratory for Marine Science and TechnologyQingdao266000China

In summer 2020,extreme rainfall occurred throughout the Yangtze River basin,Huaihe River basin,and southern Yellow River basin,which are defined here as the central China(CC)***,only a weak central Pacific(CP)El Niño happened during winter 2019/20,so the correlations between the El Niño–Southern Oscillation(ENSO)indices and ENSO-induced circulation anomalies were insufficient to explain this extreme precipitation *** this study,reanalysis data and numerical experiments are employed to identify and verify the primary ENSO-related factors that cause this extreme rainfall *** summer 2020,unusually strong anomalous southwesterlies on the northwest side of an extremely strong Northwest Pacific anticyclone anomaly(NWPAC)contributed excess moisture and convective instability to the CC region,and thus,triggered extreme precipitation in this *** tropical Indian Ocean(TIO)has warmed in recent decades,and consequently,intensified TIO basinwide warming appears after a weak El Niño,which excites an extremely strong NWPAC via the pathway of the Indo-western Pacific Ocean capacitor(IPOC)***,the ENSO event of 2019/20 should be treated as a fast-decaying CP El Niño rather than a general CP El Niño,so that the circulation and precipitation anomalies in summer 2020 can be better ***,the increasing trend of tropospheric temperature and moisture content in the CC region after 2000 is also conducive to producing heavy precipitation.

关键词： extreme rainfall Northwest Pacific anticyclone anomaly(NWPAC) Indo-western Pacific Ocean capacitor(IPOC) Tropical Indian Ocean warming trend fast-decaying El Niño

Studies on reaction mechanisms and distinct chemiluminescence from cyanoimino neonicotinoids triggered by peroxymonosulfate in advanced oxidation processes

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Chinese Chemical Letters 2023年第3期34卷 206-208页

作者： Mengdie cai Weimin Gan Zhiqin ding Hongping cai Lijun Wei Xianglei Cheng Jiangxi Province Key Laboratory of Preventive Medicine School of Public HealthNanchang UniversityNanchang 330006China

In this study, we proposed a novel method to investigate the advanced oxidation process of neonicotinoids(NNIs) from the perspective of concomitant chemiluminescence(CL) reaction. It was found that in the presence of cobalt ions with cyanoimino NNIs, acetamiprid(ACE) and thiacloprid(THI), could promote peroxymonosulfate and Ru(bpy)_(3)^(2+) to produce strong CL, but no CL occurred with nitro-involved NNIs as alternatives. Experimental dada from UV absorption spectra and chemiluminescence spectra suggested that new cyclic compounds might be formed during the reaction. Based on the results of free radical scavenging experiment and mass spectra, a new degradation and reaction mechanism of cyanoiminocontaining NNIs was proposed. ACE or THI were first attacked by SO_(4)^(·-) to form benzyl radicals, which in turn reacted with the carbon atoms of cyano group through electrophilic addition reaction in the formation of intramolecular ring. Then a redox reaction between Ru(bpy)_(3)^(3+) and imino group immediately took place with CL emission(610 nm). The new mechanistic knowledge would be meaningful for other contaminants for their interactions with PMS.

关键词： Advanced oxidation processes Chemiluminescence mechanisms Annulation reaction Peroxymonosulfate Acetamiprid Thiacloprid