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Journal of Mountain Science 2025年第2期22卷 652-665页

作者： fu Juan song Yuxin SUN Yehong Tourism College Beijing Union UniversityBeijing 100101China

Agricultural heritage systems have the characteristics of ecological fragility and cultural *** a long time,the conservation and sustainable development of agricultural heritage systems have received attention from all ***,there are few measurements of tourism disturbance(TD)and community resilience(CR)in agricultural heritage sites,and research on the relationship between the two is even more *** study selects six villages in the Honghe Hani Rice Terraced System(HHRTS)as examples and constructs an evaluation system for TD and *** questionnaires and in-depth interviews,it explores the response relationship between TD and CR of heritage site,and compares the response relationship of villages in different stages of tourism *** results indicate that the heritage site's current response relationship between TD and CR shows a positive response type,and the development of tourism has brought positive responses and *** are differences in the interactive relationship between TD and CR among communities with different levels of tourism *** communities with poor tourism development,CR is more susceptible to the impact of TD than other *** stability of the relationship between TD and CR response gradually tends to stabilize from poor,good,and moderate tourism development.

关键词： Tourism disturbance Community resilience Agricultural heritage system Response relationship Honghe Hani Rice Terraced System

Gradient age-precipitation behavior induced by gradient nano-grain in Mg-Gd-Ag-Zr alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 19-24页

作者： Bang-jun Li Jia-peng Sun Jing Han Guo-song Wu College of Materials Science and Engineering Hohai UniversityNanjing 210024JiangsuChina School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116JiangsuChina

Gradient nano-grained structure is frequently engineered into metallic materials,including Mg alloys,to achieve superior combination of strength and ***,the influence of this microstructural feature on aging precipitation behavior remains inadequately *** this study,the age-precipitation behavior of a gradient nano-grained Mg-Gd-Ag-Zr alloy prepared via ultrasonic severe surface rolling was *** result indicates that the aging precipitation behavior exhibits a depth-dependent variation within this *** the nano-grained surface layer,hierarchicalβnano-precipitates are predominant,while at greater depths,the precipitates consist ofβnanoparticles located at grain boundaries,along with intragranularβ′andγ″*** formation ofβnano-precipitates deviates from the conventional precipitation behavior observed in Mg-Gd-Ag alloys,and is attributed to the high density of defects induced by the surface nano-grained *** finding advances our understanding of the precipitation behavior in the alloys with heterogeneous microstructure.

关键词： Mg alloy Gradient Precipitation Aging behavior Microstructure

Crevice corrosion of reinforcing steel in carbonated simulated concrete pore solutions contaminated by chloride

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Journal of Iron and Steel Research International 2025年第1期32卷 293-311页

作者： peng-peng Wu Yuan-pei Gong Shao-hua Zhang Yue-zhong Zhang Bao-sheng Liu Guang-ling song College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen518055GuangdongChina School of Mechanical and Mining Engineering Centre for Advanced Materials Processing and Manufacturing(AMPAM)The University of QueenslandSt LuciaQLD4072Australia State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen361005FujianChina

The crevice corrosion of the reinforcing steel in the carbonated simulated concrete pore solutions(SCPSs)containing 0.04 mol/L chloride was *** comparison,the steel without crevice covered on its surface was also *** showed that the crevice corrosion in the uncarbonated SCPS was not triggered and the steel remained passivity by suppressing the anodic dissolution in the crevice *** SCPS was carbonated to have pH values of 10.5 and 11.5,the crevice corrosion was easier to be activated than the widely reported pitting corrosion owing to the rapid oxygen depletion within the crevice,but the crevice corrosion damage might be alleviated to a certain extent due to the relative compact surface film formed inside the *** further carbonation led to the activation dissolution of both the crevice interior and exterior,causing the more serious corrosion *** process of the crevice corrosion was systematically analyzed by combining the electrochemical measurement results and Evens polarization diagram.

关键词： Crevice corrosion Reinforcing steel Carbonation Electrochemical test Rust Evens polarization diagram

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu song Gu fulong Chen Zhe Zhao peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences(RAD-X)Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China

The efficient separation of fission products,such as TcO_(4)^(-)and I^(-),holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis(bromomethyl)benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups(Cl@QPN),exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/(mg min)for ReO_(4)^(-)(a nonradioactive surrogate of TcO_(4)^(-))and 0.677 g/(mg min)for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO_(4)^(-)and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for^(99)TcO_(4)^(-).Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO_(4)^(-),respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： peng Wang Jianjun Wang Ni song Xin Zhou Ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao peng Yuefeng song Ihar Razanau Juanxiu Xiao Wei Xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of BelarusMinsk 220072Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and TechnologySchool of Marine Science and EngineeringHainan UniversityHaikou 570228HainanChina Department of Chemical and Environmental Engineering University of Nottingham Ningbo ChinaNingbo 315100ZhejiangChina

Methane, an abundant one-carbon(C_(1)) resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO_(2)emissions and coke deposition. Electrochemical conversion of methane(ECM) using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO_(2)emission.

关键词： Methane Electrochemical conversion Reaction mechanism Catalyst design Electrode Electrocatalysis

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志贺菌基因组进化研究进展

生物化学与生物物理进展 2016年第11期43卷 1029-1037页

作者：杨朗邱少富李鹏宋宏彬军事医学科学院疾病预防控制所北京100071

志贺菌属(Shigella)是引起全球范围内细菌性痢疾的重要病原菌.近年来,多重耐药型和新血清型志贺菌的不断出现给志贺菌的监测和防控带来了新的挑战.基因组学的快速发展为深入了解志贺菌的进化来源、变异机制及传播规律等提供了极大的帮助... 详细信息

志贺菌属(Shigella)是引起全球范围内细菌性痢疾的重要病原菌.近年来,多重耐药型和新血清型志贺菌的不断出现给志贺菌的监测和防控带来了新的挑战.基因组学的快速发展为深入了解志贺菌的进化来源、变异机制及传播规律等提供了极大的帮助,对控制细菌性痢疾的蔓延具有重要的科学意义.本文首先从遗传来源角度探讨志贺菌与大肠杆菌的进化关系及其可能的分子机制,随后对福氏、宋内和1型痢疾志贺菌的基因组进化进展进行了总结,详细描述了它们的时空分布特点以及耐药基因变异在进化中所发挥的作用,以期为志贺菌的研究和防控提供参考.

关键词：志贺菌基因组进化关系大肠杆菌

Carbon emissions in China’s steel industry from a life cycle perspective:Carbon footprint insights

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Journal of Environmental Sciences 2025年第2期148卷 650-664页

作者： Xiaocong song Shuai Du Chenning Deng peng Shen Minghui Xie Ci Zhao Chen Chen Xiaoyu Liu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Water Resources&Environmental Engineering China University of Geosciences(Beijing)Beijing 100083China Chinese Research Academy of Environmental Sciences Environmental Technology&Engineering Co.Ltd. Beijing 100012China

China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in ***,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development *** constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life *** emission reduction factors were identified using sensitivity *** results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle ***,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than *** the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system.

关键词： Iron and steel industry Life cycle Carbon dioxide(CO_(2))emissions Carbon footprint China

Efficient conversion of chitin to HMF under the cocatalytic system of formic acid and silicotungstic acid

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Journal of Oceanology and Limnology 2025年第1期43卷 261-273页

作者： Luxiao ZHOU Kun GAO peng HE Huahua YU Ronge XING song LIU Yukun QIN College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042China CAS and Shandong Province Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Drugs and Bioproducts Qingdao Marine Science and Technology CenterQingdao 266237China

The conversion process of chitin,one of the abundant biomass resources on the earth,not only follows the principles of green chemistry,but also has significant value in industrial ***,it is a great challenge to directly convert insoluble and rigid structured chitin to 5-hydroxymethylfurfural(HMF).To address this issue,we developed a green conversion process combining pretreatment and catalytic *** was first pretreated by hexafluoro isopropanol(HFIP),which somewhat disrupted the hydrogen bonding network within the chitin ***,formic acid(FA)and silicotungstic acid(STA)synergistically catalyzed the conversion to HMF in a biphasic system of 2-methyltetrahydrofuran(2-Me-THF)/H2O,and high yields(40.2%)HMF was obtained under the optimism *** product distribution was analyzed by HPLC-MS and the co-catalysis of FA with STA was evidenced.A dual-function catalytic system with both Lewis and Br?nsted acids was created,the catalytic system that significantly improved the efficiency of complex tandem catalytic reactions with *** on the experimental results,a possible pathway for chitin conversion was deduced,providing a new catalytic idea for the efficient conversion of chitin to HMF.

关键词： chitin 5-hydroxymethylfurfural 2-Me-THF/H2O biphasic system Lewis and Br?nsted acid

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扑翼的推力特性与功率特性的实验研究

西北工业大学学报 2016年第6期34卷 976-981页

作者：付鹏宋笔锋梁少然杨文青西北工业大学航空学院陕西西安710072

针对扑翼实验动态特性强、测控变量多的特点,设计了一种实验专用的扑动机构,在实现对扑动频率和扑动幅度精确调控的同时,集成了对瞬时扑动角度和输入功率的测量功能,建立了一套适用于扑翼风洞实验的测控系统,能够实现对动态气动力、扑... 详细信息

针对扑翼实验动态特性强、测控变量多的特点,设计了一种实验专用的扑动机构,在实现对扑动频率和扑动幅度精确调控的同时,集成了对瞬时扑动角度和输入功率的测量功能,建立了一套适用于扑翼风洞实验的测控系统,能够实现对动态气动力、扑动角度、扑动翼输入功率等量的实时同步测量;在此基础上针对扑翼的推力特性和功率特性进行了风洞实验研究,着重分析了在不同扑动频率和不同扑动幅度情况下扑翼的推力与功率特性;实验结果表明,在研究的范畴内,扑动频率和扑动幅度的增大都有利于推力的产生,但都会增大对应的功耗;推力和功耗都随St的增大呈"J"型曲线增长,当St小于0.25时,推力和功耗的增长趋势较缓,随着St的增大,尤其当St大于0.3时,推力和功耗将大幅增大。

关键词：微型扑翼飞行器推力特性功率特性风洞实验测控系统