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nano research 2024年第7期17卷 5856-5862页

作者： xingyu Liu xue Yang han sun Zekai Yang Haijun chen Tianjin Key Laboratory of Optoelectronic Thin Film Devices and Technology College of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and *** address the challenges associated with the direct usage of ammonia,the development of nH_(3)-to-H_(2)conversion technologies has emerged as a promising and effective ***,we present for the first time that crystallized Sm_(2)O_(3−x)electrodes demonstrate high and stable electrocatalytic activities,including n_(2)evolution rate and Faradaic efficiency,for ammonia electrolysis in a non-aqueous *** was observed that Sm^(2+)ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the ***,the mechanism of ammonia electrooxidation has also been elucidated,laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H_(2).

关键词： nH_(3)-to-n_(2)conversion ammonia electrooxidation reaction ammonia electrolysis non-aqueous electrolyte samarium oxide

role of adaptation measures in addressing heatwave exposure in China

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Advances in Climate Change research 2024年第1期15卷 148-157页

作者： Qin-Mei han Qing-chen CHAO Shao sun Pei-Jun SHI national Climate Centre China Meteorological AdministrationBeijing 100081China State Key Laboratoryof Severe Weather Chinese Academy of Meteorological Sciences Beijing 0o08lChina Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

Heatwave exposure has increased dramatically because of climate warming and population growth,along with their interactive ***,effective adaptation measures can reduce these ***,the dynamic changes,regional inequality in adaptive capacity and their potential contributions to reducing exposure in the future remain *** study quantifies the impact of adaptive capacity and underscores regional variations in heatwave magnitudes,population exposure and adaptation levels in *** projected the future adaptive capacity using air-conditioner penetration,factoring in climate cooling requirements and individuals'purchasing *** population and gross domestic product(GDP)data from four Shared Socioeconomic Pathways(SSP1,SSP2,SSP3 and SSP5)and daily temperature data from four SSP-based emission scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0 and SSP5-8.5),we estimated heatwave duration,population exposure and avoided impacts through adaptation across China and its *** show a substantial increase in heatwave duration in Southwest and Southern China,especially under the SSP5-8.5 scenario,with a projection of 163.2±36.7 d during *** the SSP3|SSP3-7.0 scenario,total exposure reaches 156.4±76.8 billion person d per year,which is the highest among all scenarios and 23 times greater than that in 1986-2005 without *** considering adaptation measures,a noteworthy reduction in population exposure is observed,especially in the SSP3|SSP3-7.0 and SSP5JSSP5-8.5 scenarios,with reductions of(62.6±3.9)%and(65.8±5.1)%,respectively,compared with the scenario without adaptation during *** regional disparities in avoided impacts are also evident,with variations of up to 50%across different *** implementation of effective and environmentally friendly adaptation measures can notably address climate change,thereby alleviating the profound threats posed to human well-being.

关键词： Heatwaves Population exposure Adaptation Future projection China

Palladium-Catalyzed[4+2]and[6+2]Dipolar Cycloadditions for the Construction of Benzo[d]isothiazole 1,1-Dioxide Fused 1,3-Oxazinanes and 1,3-Oxazocanes

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Chinese Journal of Chemistry 2024年第8期42卷 829-834页

作者： Lei chen Hongling xie Yu xue Zhengyu han Jianwei sun Hai Huang Jiangsu Key Laboratory of Advanced Catalytic Materials&Technology School of Petrochemical EngineeringChangzhou UniversityChangzhouJiangsu213164 China Department of Chemistry The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina

Comprehensive Summary,The Pd-catalyzed dipolar cycloaddition represents a significant synthetic strategy for the construction of useful heterocyclic *** study developed the dipolar[4+2]and[6+2]cycloaddition reactions of benzo[d]isothiazole 1,1-dioxides(BDs)leading to the synthesis of BD-fused 1,3-oxazinane and 1,3-oxazocane derivatives,*** particular,the synthesis of BD-fused 1,3-oxazinanes demonstrated regio-and enantioselective characteristics,resulting in products with good yields,enantioselectivity and regioselectivity(if applicable).Furthermore,the[6+2]cycloaddition reaction developed in this work represented the first strategy for the synthesis of medium-sized ring compounds based on BDs.

关键词： Cycloaddition 1,3-Oxazinanes 1,3-Oxazocanes Medium-ring compounds Stereochemistry n-Heterocycles Sulfonamides Enantioselectivity Asymmetricsynthesis

Yolk-shell FeCu/nC electrocatalyst boosting high-performance zinc-air battery

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nano research 2024年第9期17卷 7918-7925页

作者： chen Liang Tianyu Zhang Shilun sun Aijuan han Zenghui Qiu Haijun xu Junfeng Liu State Key Laboratory of Chemical resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Mathematics&Physics Beijing University of Chemical TechnologyBeijing 100029China Beijing Bioprocess Key Laboratory Beijing University of Chemical TechnologyBeijing 100029China

Iron-nitrogen-carbon single-atom catalysts(Fe-n-C SACs)are widely acknowledged for their effective oxygen reduction activity,however,their activity requires further ***,additional structural optimization is necessary to enhance mass transport and achieve higher power density in practical ***,using ZIF-8 as a template,we synthesized yolk-shell catalysts featuring complex sites of Fe single atoms and Cu nanoclusters(y-FeCu/nC)via partial etching and liquid-phase *** synthesized y-FeCu/nC catalyst exhibits high specific surface area and mesoporous *** with the advantages of highly active sites and yolk-shell structure,the y-FeCu/nC catalyst demonstrated outstanding catalytic performance in the oxygen reduction reaction,achieving a half-wave potential(E_(1/2))of 0.97 V in 0.1 M *** a practical energy device,Zn-air battery(ZAB)assembled with y-FeCu/nC catalyst achieved a remarkable power density of 356.3 mW·cm^(-2),representing an improvement of approximately 28.5%compared to its solid FeCu/nC ***,it showcased impressive stability,surpassing all control samples.

关键词： atomic Fe-n4 sites Cu nanoclusters yolk-shell structure oxygen reduction reaction zinc-air battery

Effect of Fe_(2)O_(3)on the Structure,Physical Properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 954-961页

作者：张峰 xIOnG Dehua 谢俊张继红 han Jianjun chen Dequan WEn Zhongquan FAn Zhenhua chen Lina sun Tengfei State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Hepu research Center for Silicate Materials Industry Technology Beihai 536100China Hainan Institute of Wuhan University of Technology Sanya 430079China Shenzhen research Institute of Wuhan University of Technology Shenzhen 518000China Chongqing Polycomp Inter-national Corporation Chongqing 400400China

The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching *** glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,x-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope *** change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass *** glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content *** is almost no thermal expansion coefficient change from different Fe_(2)O_(3)*** glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)*** calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional *** of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals.

关键词： calcium aluminosilicate glass network structure physical properties crystallization

Feasibility Study on recovering Human-Occupied Vehicle with An Offshore Crane

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China Ocean Engineering 2024年第4期38卷 648-662页

作者： han Ming-yue xIE Peng xIAn Hao-yi ZHOnG xin-xin chen Sheng-lin sun Tie-rui sun Feng-lei School of Ocean Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(sun Yat-sen University) Ministry of EducationZhuhai 519082China Guangzhou Marine Engineering Corporation Guangzhou 510250China

Launching and recovering human-occupied vehicles(HOVs)has always been a challenging *** current recovery process requires staff to manually complete the tethering task,which is inefficient and endangers the lives of *** paper suggests moving the recovery position from the surface to underwater at approximately half the wavelength of the water depth(30−50 m underwater),where the HOV experiences less environmental *** rOV equipped with a ultra-short baseline beacon(USBL)and a manipulator was used to complete the tethering ***,a shackle customized to the shape of the manipulator’s gripper is fitted to the end of the cable to simplify the tethering *** investigate the dynamic response of recovering the HOV using this suggested method,a comprehensive numerical model is developed in this *** effects of wind,surface waves,ocean currents,and nonlinear interaction between the installation vessel and the HOV are quantitatively *** results show that the proposed recovery method can reduce the motion amplitude of the HOV and that the wave has the greatest influence on the dynamic response of the HOV during the recovery *** model provides better insight into the proposed HOV recovery method and confirms the effectiveness of the heave compensation *** proposed approach aims to enhance safety and operational efficiency by reducing direct human involvement in the recovery process and mitigating potential *** finding holds particular significance,especially in environmentally sensitive areas,where reducing the impact on the surrounding ecosystem is crucial.

关键词： human-occupied vehicle recovery dynamic response active heave compensation

Preparation of high-purity fluorite and nanoscale calcium carbonate from low-grade fluorite

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1198-1207页

作者： Qianqian Lu Haisheng han Wenjuan sun xingfei Zhang Weiwei Wang Bilan Zhang Wensheng chen Qin Zou School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Hunan nonferrous chenzhou Fluoride Chemical Co. Ltd.Chenzhou 423000China State Key Laboratory of Baiyunobo rare Earth resource researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China Hunan Shizhuyuan nonferrous Metal Co. Ltd.Chenzhou 423000China

Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed in this *** innovative process raised the fluor-ite’s grade to 97.26wt%while producing nanoscale calcium carbonate from its leachate,which contained plenty of calcium *** the production of nanoscale calcium carbonate,the impacts of concentration,temperature,and titration rate were *** modifying the process conditions and utilizing crystal conditioning agents,calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511μm were *** influence of the impurity ions Mn^(2+),Mg^(2+),and Fe^(3+)was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride *** combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources,thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles.

关键词： fluorite calcite nanoscale calcium carbonate waste recovery

Cellular Cd^(2+)fluxes in roots confirm increased Cd availability to rice(Oryza sativa L.)induced by soil acidifications

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Journal of Environmental Sciences 2024年第5期139卷 516-526页

作者： xiaoyi sun Meng Wang Luyao Qin Lei Yu Jing Wang han Zheng Wenneng Zhou Shibao chen State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in northern China/Institute of Agricultural resources and regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological restoration for Watersheds School of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China

Soil acidifications become one of the main causes restricting the sustainable development of agriculture and causing issues of agricultural product *** order to explore the effect of different acidification on soil cadmium(Cd)availability,soil pot culture and hydroponic(soil potting solution extraction)were applied,and non-invasive micro-test technique(nMT)was *** three different soil acidification processes were simulated,including direct acidification by adding sulfuric acid(AP1),acid rain acidification(AP2)by adding artificial simulated acid rain and excessive fertilization acidification by adding(nH_(4))_(2)SO_(4)(AP3).The results showed that for direct acidification(AP1),DTPA-Cd concentration in field soils in Liaoning(S1)and Zhejiang(S2)increased by 0.167-0.217 mg/kg and 0.181-0.346 mg/kg,respectively,compared with control *** soil pH decreased by 0.45 units in S1,the Cd content of rice stems,leaves and roots increased by 0.48 to 6.04 mg/kg and 2.58 to 12.84mg/kg,respectively,When the pH value of soil S1 and S2 decreased by 0.20 units,the average velocity of Cd^(2+)at 200μm increased by 10.03-33.11 pmol/cm~2/sec and 21.33-52.86pmol/cm^(2)/sec,respectively,and followed the order of AP3>AP2>*** summary,different acidification measures would improve the effectiveness of Cd,under the same pH reduction condition,fertilization acidification increased Cd availability most significantly.

关键词： Soil acidification Cadmium non-invasive micro-test technique Bioavailability

Highly efficient CO_(2) capture using 2-methylimidazole aqueous solution on laboratory and pilot-scale

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Chinese Journal of Chemical Engineering 2024年第3期67卷 148-156页

作者： Kun Li han Tang Shuangshuang Li Zixuan Huang Bei Liu Chun Deng Changyu sun Guangjin chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Zhejiang Tiandi Environmental Protection Technology Co. Ltd.Hangzhou 310012China

To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of ***,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous *** properties and sorption behaviors of this approach have been experimentally *** results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 *** selectivity for CO_(2)/n_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,***,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.

关键词： CO_(2) capture Absorption 2-Methylimidazole Separation Pilot-scale tests

Additive manufacturing of niTi lightweight porous structures bio-mimicking coral skeleton with enhanced mechanical properties and shape memory functions

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Science China(Technological Sciences) 2024年第8期67卷 2461-2474页

作者： LIU xin GU DongDong YUAn LuHao ZhanG han sun JianFeng chen Wenxin WAnG Jie SHI KeYu Jiangsu Provincial research Center for Laser Additive Manufacturing of High-Performance Components College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

Concerning the high demand for lightweight and multifunctional properties of engineering structures, the coral skeleton-inspired sheet-based(CSS) structure, which was a novel bio-mimicking coral skeleton wall-septa architecture with a unique ability to resist wave shocks was fabricated using niTi alloy by laser powder bed fusion(LPBF) technology. The effects of laser energy density(LED) on surface morphologies, microstructures, phase transformation behavior, and mechanical properties of LPBFfabricated CSS structures were systematically investigated. The results indicated that the size deviation was predominantly governed by powder adhesion and step effect. niTi CSS structures with LED of 71 J·mm~(-3)possessed superior compressive modulus(~400 MPa), ultimate strength(~13 MPa), and energy absorption efficiency(~69%). The compression fracture mechanism of the LPBF-fabricated niTi CSS structures was revealed to be predominantly brittle fracture accompanied by ductile fracture. Furthermore, the ni_4Ti_3 nanoprecipitates induced the precipitation strengthening effect, enabling better shape memory response at LED of 71 J·mm~(-3), with a recoverable strain of 3.63% and recovery ratio of 90.8%, after heating under a pre-strain of 4%. This study highlights the importance of a bionic design strategy for enhancing the mechanical properties of niTi components and offers the possibility to tailor its functional properties.

关键词： bioinspired structures laser powder bed fusion niTi shape memory alloy mechanical performance

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