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Conversion of Metallurgical Waste:The Impact of Reduction Ferrum Extraction on the Phase Composition and Cementitious Materials Reactivity of Jinchuan Ferronickel Slag
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作者 SONG Yanning FENG Qiong +2 位作者 QIAO Hongxia WEI Chao ZHENG Jianghua 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期546-557,共12页
In order to avoid the waste of iron caused by the direct use of ferronickel slag(FNS)in building materials,the effects of reduction iron extraction on the physical and chemical properties,cementitious reactivity and h... In order to avoid the waste of iron caused by the direct use of ferronickel slag(FNS)in building materials,the effects of reduction iron extraction on the physical and chemical properties,cementitious reactivity and hydration reaction characteristics of FNS and ferrum extraction tailing of nickel slag(FETNS)were studied.The experimental results show that the reduction ferrum extraction method changes the mineral phase composition of the waste slag,breaks the Si-O-Si bond,forms the tetrahedral structure of Si-O-NBO or Si-O-2NBO,and increases the content of active components such as Ca,Si,Mg,and Al.Compared with FNS,the 28 d compressive strength of pastes prepared by FETNS increases by 16.12%,22.57%,33.13%,44.26%,and 57.65%,respectively.The degree of hydration reaction of the composite cementitious systems in the FETNS group is higher than that in the FNS group at different ages,and the content of hydration products such as C-S-H gel and ettringite(AFt)is also higher than that in the FNS group.More hydration products can improve the curing ability to Cr and Mn of the composite cementitious systems in the FETNS group,and reduce the leaching value of Cr and Mn. 展开更多
关键词 ferronickel slag reduction ferrum extraction physical and chemical properties cementitious material
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Manganese extraction by reduction-acid leaching from low-grade manganese oxide ores using CaS as reductant 被引量:4
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作者 李昌新 钟宏 +3 位作者 王帅 薛建荣 武芳芳 张振宇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1677-1684,共8页
The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to ... The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to solid ratio(L/S ratio), stirring speed, leaching temperature, leaching time and H2SO4 concentration on the leaching rates of Mn and Fe during the reduction–acid leaching process were discussed. The leaching rates of 96.47% for Mn and 19.24% for Fe were obtained under the optimized conditions of mass ratio of Ca S to manganese oxide ore 1:6.7, L/S ratio 5:1, stirring speed 300 r/min, reduction temperature of 95 °C for 2.0 h in the reduction process and leaching stirring speed of 200 r/min, H2SO4 concentration of 1.5 mol/L, leaching temperature of 80 °C for 5 min in the leaching process. In addition, this process can be employed in the recovery of manganese from various manganese oxide ores, and Mn leaching rate above 95% is obtained. 展开更多
关键词 MANGANESE manganese oxide ore calcium sulfide reduction LEACHING
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Quantifying Global Black Carbon Aging Responses to Emission Reductions Using a Machine Learning-based Climate Model 被引量:1
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作者 Wenxiang SHEN Minghuai WANG +5 位作者 Junchang WANG Yawen LIU Xinyi DONG Xinyue SHAO Man YUE Yaman LIU 《Advances in Atmospheric Sciences》 2026年第2期361-372,I0004-I0009,共18页
Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model versi... Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model version 6 with a machine-learning-integrated four-mode version of the Modal Aerosol Module, we quantify global BC aging responses to emission reductions for 2011–2018 and for 2050 and 2100 under carbon neutrality. During 2011–18, global trends in BC aging degree(mass ratio of coatings to BC, R_(BC)) exhibited marked regional disparities, with a significant increase in China(5.4% yr^(-1)), which contrasts with minimal changes in the USA, Europe, and India. The divergence is attributed to opposing trends in secondary organic aerosol(SOA) and sulfate coatings, driven by regional changes in the emission ratios of corresponding coating precursors to BC(volatile organic compounds-VOCs/BC and SO_(2)/BC). Projections under carbon neutrality reveal that R_(BC) will increase globally by 47%(118%) in 2050(2100), with strong convergent increases expected across major source regions. The R_(BC) increase, primarily driven by enhanced SOA coatings due to sharper BC reductions relative to VOCs, will enhance the global BC mass absorption cross-section(MAC) by 11%(17%) in 2050(2100).Consequently, although the global BC burden will decline sharply by 60%(76%), the enhanced MAC partially offsets the magnitude of the decline in the BC direct radiative effect, resulting in the moderation of global BC DRE decreases to 88%(92%) of the BC burden reductions in 2050(2100). This study highlights the globally enhanced BC aging and light absorption capacity under carbon neutrality, thereby partly offsetting the impact of BC direct emission reductions on future changes in BC radiative effects globally. 展开更多
关键词 black carbon aging trend emission reduction carbon neutrality machine learning
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Comparison of Electrolytic Reduction and Lithium Reduction of ZnO in Molten LiCl
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作者 XU Jitang REN Guangzhi +7 位作者 YAO Benlin JIA Yanhong XIAO Yiqun YANG Mingshuai WANG Yilin SHEN Zhenfang HE Hui LI Bin 《有色金属(中英文)》 北大核心 2026年第2期269-286,共18页
In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride ... In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride molten salt as the reaction medium at 923 K.The study assessed the effects of lithium thermochemical reduction and electrolytic reduction of ZnO.The volatilization behavior of metal oxides in molten salts,the equivalent of a reducing agent,reduction time,amount of molten salt,stirring time,and the method of reduction feed were investigated for their impacts on the reduction yield and product composition.X-ray powder diffraction(XRD)analysis of the products showed that lithium reduction of ZnO not only produced metallic Zn but also formed a LiZn alloy.Electrolytic reduction can be used to obtain the metallic Zn product by controlling the potential below-2.2 V(vs Ag/Ag^(+)).Moreover,sintered oxides and higher electrode potentials could enhance the efficiency of electrolysis.Under the optimal reaction conditions determined experimentally,the lithium reduction experiment achieved a yield of 77.2%after a 12-h test,and the electrolytic reduction reached a yield of 85.4%after a 6-h test. 展开更多
关键词 pyroprocessing zinc oxide electrolytic reduction molten salt lithium reduction
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Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel 被引量:1
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作者 Lou Zhang Shuo Li +4 位作者 Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期504-514,共11页
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are... Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings. 展开更多
关键词 silver nanoparticles HYDROGEL STRAW extraction ANTIBACTERIAL
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Rapid and Controlled Reduction of Acyl Chlorides to Aldehydes Using Pinacolborane
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作者 Liu Huiyang Chen Du +2 位作者 Su Yijin Zhang Peng Liu Chao 《有机化学》 北大核心 2026年第2期564-569,共6页
A method for the rapid reduction of acyl chlorides to aldehydes was developed using pinacolborane(HBpin)as the reducing agent.The method exhibits excellent generality for both aromatic and aliphatic substrates,affordi... A method for the rapid reduction of acyl chlorides to aldehydes was developed using pinacolborane(HBpin)as the reducing agent.The method exhibits excellent generality for both aromatic and aliphatic substrates,affording aldehydes in isolated yields of up to 88%with broad functional group tolerance,including cyano,halogen,alkenyl,ketone,and ester groups.Moreover,the method enables gram-scale aldehyde synthesis and shows high efficiency in reducing in situ generated acyl chlorides,thereby enhancing its synthetic practicality. 展开更多
关键词 PINACOLBORANE reduction acyl chlorides ALDEHYDES
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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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Efficient Model Reduction of Linear Time-varying Systems via Shifted Legendre Polynomial Approximations
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作者 XIAO Zhihua TANG Man ZHU Zhihui 《应用数学》 北大核心 2026年第2期481-493,共13页
This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramia... This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramians directly from the expansion coefficients of impulse responses.Leveraging these factors,we develop two model reduction algorithms that integrate the low-rank square root method with dominant subspace projection.Our method is computationally efficient and flexible,requiring only a few matrix-vector operations and a singular value decomposition of a low-dimensional matrix,thereby avoiding the need to solve differential Lyapunov equations.Numerical experiments confirm the effectiveness of the proposed approach. 展开更多
关键词 Model reduction Time-varying systems Low-rank Gramians Balanced truncation Shifted Legendre polynomials
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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Smart Global Poverty Reduction Cooperation
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作者 LU JIAJUN 《China Today》 2026年第1期39-41,共3页
Experts and officials shared their insights on poverty reduction cooperation and sustainable development during the 2025 International Seminar on Global Poverty Reduction Partnerships.
关键词 sustainable development international seminar OFFICIALS global poverty reduction cooperation experts poverty reduction
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Far-UVC-driven Cr(Ⅵ)reduction in alkaline solution:Synergistic effects of iodide and sulfite
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作者 Yida Huang Min Zhao +2 位作者 Guoxin Li Yan Lin Lei Wang 《Journal of Environmental Sciences》 2026年第2期405-413,共9页
Hexavalent chromium(Cr(Ⅵ)) is an extremely toxic pollutant in aqueous environment.Chemical reduction is the most employed method in decontamination of Cr(Ⅵ).However,the chemical reduction was usually conducted in ac... Hexavalent chromium(Cr(Ⅵ)) is an extremely toxic pollutant in aqueous environment.Chemical reduction is the most employed method in decontamination of Cr(Ⅵ).However,the chemical reduction was usually conducted in acidic media,resulting in considerable waste of acid reagents and the following neutralizing agents.In this study,kinetics and mechanisms of Cr(Ⅵ) reduction by sulfite in alkaline conditions(pH:7-10) were investigated.It reveals that Cr(Ⅵ) reduction follows pseudo-zero-order kinetics,where the rate constants increased markedly with an in situ irradiation of Far-UVC(UV_(222)).Decreasing pH levels slightly favored the reduction.Iodide ion displayed a notable accelerating effect,which not only save the energy input but also minimize the reductant usage.Chloride,sulfate,and carbonate ions exhibit little effect on the reduction,whereas nitrate and nitrite ions,dissolved oxygen as well as Cu(Ⅱ) suppressed the reduction significantly,implying that hydrated electrons produced by UV222 played the most important role in the reaction.Compared to the UV254/sulfite/iodide process,UV222/sulfite/iodide demonstrates clear advantages in the reduction kinetics and the sulfite utilization efficiency,underscoring its potential for effective Cr(Ⅵ) remediation in various environmental settings. 展开更多
关键词 Far-UVC Advanced reduction processes Alkaline media Water matrices Cr(Ⅵ)reduction
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Comparative Study on the Efficacy of Closed Reduction and Kirschner Wire Fixation versus Open Reduction and Plate Fixation in the Treatment of Hand Surgery Fractures
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作者 Weishun Wang 《Journal of Clinical and Nursing Research》 2026年第2期81-87,共7页
Objective: To investigate the therapeutic advantages of closed reduction and Kirschner wire fixation versus open reduction and plate fixation in patients with hand surgery fractures. Methods: The sample was collected ... Objective: To investigate the therapeutic advantages of closed reduction and Kirschner wire fixation versus open reduction and plate fixation in patients with hand surgery fractures. Methods: The sample was collected from May 2021 to May 2025, consisting of 80 patients with hand surgery fractures. These patients were randomly divided into two groups using the red and blue ball method: the plate fixation group (40 cases, treated with open reduction and plate fixation) and the Kirschner wire fixation group (40 cases, treated with closed reduction and Kirschner wire fixation). The therapeutic effects between the two groups were randomly compared. Results: The Kirschner wire fixation group outperformed the plate fixation group in all indicators except for hand function scores (p < 0.05). There was no statistically significant difference in hand function scores between the two groups (p > 0.05). Conclusion: Compared with open reduction and plate fixation, closed reduction and Kirschner wire fixation for patients with hand surgery fractures achieves a more pronounced therapeutic effect, with advantages such as less trauma, shorter operation time, less bleeding, and a lower incidence of complications. It is suitable for hand surgery fractures with good stability. Open reduction and plate internal fixation have greater advantages in complex fractures and cases requiring high stability, and are worthy of promotion and application. 展开更多
关键词 Closed reduction and Kirschner wire fixation Open reduction and plate fixation Hand surgery fractures
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
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Systematic explorations for the effect of nitric acid on radiolysis of TODGA/kerosene:extraction behavior and DFT investigations for the complexation of lanthanides
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作者 Jia-Wei Zheng Shu-Yi Yang +2 位作者 Hao Wu Yan Wu Yue-Zhou Wei 《Nuclear Science and Techniques》 2026年第5期264-277,共14页
N,N,N',N'-tetraoctyl diglycolamide(TODGA)is a potential extractant for the co-extraction of lanthanides and actinides in high-level liquid waste.In this study,the radiolysis and extraction properties of TODGA ... N,N,N',N'-tetraoctyl diglycolamide(TODGA)is a potential extractant for the co-extraction of lanthanides and actinides in high-level liquid waste.In this study,the radiolysis and extraction properties of TODGA in kerosene solvents contacted with the aqueous phase of varying HNO_(3) concentrations were systematically investigated,and the complexation mechanism was analyzed in conjunction with density functional theory(DFT)calculations.After γ-irradiation,the variation of TODGA concentration was detected,and the variation trends in the relative content of radiolysis products(RPs)with sample type and absorbed dose were demonstrated.Results indicated that the breaking of the amide bond,ether bond,and C_(amide)-C_(ether)bond was the primary radiolysis routes.The aqueous-phase precipitate was studied as a potential new mode of TODGA radiolysis in ultrapure water aqueous phase.Moreover,TODGA/kerosene exhibited excellent extraction capabilities for lanthanides even after absorbing 100 kGy,and HNO_(3) can maintain a portion of TODGA's extraction capacity.The DFT method was applied to calculate and evaluate the complexing ability of TODGA and some of its RPs toward lanthanides.The results revealed that the complexing ability of TODGA for Ce(Ⅲ),Eu(Ⅲ),and Dy(Ⅲ)was enhanced successively,and the complexing ability of the RPs with intact oxygen-containing structures could not be neglected. 展开更多
关键词 TODGA KEROSENE Systematic research Radiolysis product extraction DFT calculation
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Unveiling the role of Ru nanoclusters in Ru-CuO_(x) nanowires for electrochemical nitrate reduction to ammonia
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作者 Jian Li Jinzhi Jia +10 位作者 Zhongwei Wang Huijiao Wang Junfeng Huang Yantao Wang Wenhan Dai Peng-an Chen Jinhua Zhang Mudong Tu Hua Li Haiyan Ma Cailing Xu 《Journal of Energy Chemistry》 2026年第2期198-206,I0006,共10页
Electrochemical nitrate reduction reaction(NO_(3)RR)is a sustainable strategy to treat wastewater and produce ammonia.However,it is still a challenge to prepare electrocatalysts with high activity and selectivity.Here... Electrochemical nitrate reduction reaction(NO_(3)RR)is a sustainable strategy to treat wastewater and produce ammonia.However,it is still a challenge to prepare electrocatalysts with high activity and selectivity.Herein,the CuO_(x) nanowires supported Ru nanoclusters(Ru-CuO_(x))were fabricated via a three-step procedure for efficient nitrate conversion and highly selective ammonia generation.The prepared RuCuO_(x) shows a high ammonia yield rate of 2286.5μg h^(-1) cm^(-2) at-0.7 V vs.RHE and Faradaic efficiency(FE)of 80.1%at-0.4 V vs.RHE.Additionally,the nitrate conversion rate exceeds 90%at the potential range from-0.2 to-0.7 V vs.RHE,and the ammonia selectivity can reach 97.7%at-0.7 V vs.RHE in100 mg L^(-1) NaNO_(3) solution.The systematic characterizations clarify that the introduction of Ru not only regulates the electronic structure of CuO_(x) and accelerates the reconstruction of CuO_(x) to Cu but also promotes H2O dissociation to generate active hydrogen.Moreover.in-situ Raman spectroscopy reveals that the formed Ru-Cu is considered the actual active species during the NO_(3)RR.Density functional theory(DFT)calculations further prove that the obtained Ru-Cu facilitates the adsorption of nitrate and lowers the Gibbs free energy of the rate-determining step,thus improving the NO_(3)RR performance. 展开更多
关键词 Electrochemical nitrate reduction AMMONIA Reconstruction NANOCLUSTERS Active hydrogen
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Flexible resource allocation for power systems to maximize diversified values in resilience,carbon reduction and renewable energy consumption
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作者 Zhaohong Bie Yiheng Bian Chenxing Yang 《iEnergy》 2026年第1期43-54,共12页
The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource a... The energy transition inspired by carbon neutrality targets and the increasing threat of extreme events raise multi-objective development requirements for power systems.This paper proposes a multi-objective resource allocation model to determine the type,number and location of flexible resources to increase the values of resilience,carbon reduction and renewable energy consumption.To evaluate the values of resilience,a restoration model for transmission systems is established that considers the coordination of fossil-fuel generators,energy storage systems(ESSs)and renewable energy generators in building restoration paths.The collaborative power-carbon-tradable green certificate(TGC)market model is then applied to evaluate the resource values in terms of carbon reduction and renewable energy consumption.Finally,the model is formulated as a mixed-integer linear programming(MILP)with a nonconvex feasible domain,and the normalized normal constraint(NNC)method is applied to obtain approximate Pareto frontiers for decision makers.Case studies validate the effectiveness of the proposed model in improving multi-factor values and analyze the impact of resource regulation capacity on values of restoration and carbon reduction. 展开更多
关键词 Multi-objective planning Power system Carbon reduction RESILIENCE Flexible resource
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1D COFs with phthalocyanine functional building blocks and imide linkage for superior electrocatalytic nitrate reduction
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作者 Mingrun Li Bin Han +5 位作者 Lei Gong Yucheng Jin Mingyue Wang Xu Ding Dongdong Qi Jianzhuang Jiang 《Chinese Chemical Letters》 2026年第2期600-605,共6页
In comparison with their 2D and 3D counterparts,1D covalent organic frameworks(COFs)have rarely been investigated due to the synthetic challenge arising from the strict necessary matching in the molecular symmetry bet... In comparison with their 2D and 3D counterparts,1D covalent organic frameworks(COFs)have rarely been investigated due to the synthetic challenge arising from the strict necessary matching in the molecular symmetry between corresponding building blocks and linking units in addition to the unmanageable packing of 1D organic chains once formed.Herein,two novel imide-linked 1D COFs with phthalocyanine building blocks,namely NiPc-CZDM-COF and NiPc-CZDL-COF,were fabricated from the hydrothermal synthesis reaction of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(II)(NiPc(COOH)_(8))with 9H-carbazole-3,6-diamine(CZDM)and 4,4′-(9H-carbazole-3,6-diyl)dianiline(CZDL),respectively.Two COFs have high crystallinity on the basis of powder X-ray diffraction analysis and high-resolution transmission electron microscopy.Due to their high ratio of exposed active centers on the edge sites of porous ribbons,both NiPc-CZDM-COF and NiPc-CZDL-COF electrodes display high utilization efficiency of NiPc electroactive sites of 8.0%and 7.5% according to the electrochemical measurement,resulting in their excellent capacity toward electrocatalytic nitrate reduction with the nitrate-to-NH3 Faradaic efficiency of nearly 100%.In particular,NiPc-CZDM-COF electrode exhibits superior electrocatalytic performance with high NH_(3) partial current density of−246 mA/cm^(2),ammonia yield rate of 19.5 mg cm^(−2) h^(−1),and turnover frequency of 5.8 s^(−1) at−1.2 V in an H-type cell associated with its higher conductivity.This work reveals the good potential of 1D porous crystalline materials in electrocatalysis. 展开更多
关键词 One-dimensional Covalent organic framework PHTHALOCYANINE Nitrate reduction Electrocatalysis
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Kinetically controlled Np(Ⅵ)/Pu(Ⅳ) selective reduction by n-butyraldehyde
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作者 Xiaobo Li Qunyan Wu +3 位作者 Congzhi Wang Jianhui Lan Meng Zhang Weiqun Shi 《Chinese Chemical Letters》 2026年第2期430-436,共7页
The demand for ^(238)Pu (nuclear battery heat source) drives the separation of its precursor,^(237)Np,from spent nuclear fuel (SNF).However,the co-existence of multi-valence states (Ⅳ/Ⅴ/Ⅵ) of Np and similar redox b... The demand for ^(238)Pu (nuclear battery heat source) drives the separation of its precursor,^(237)Np,from spent nuclear fuel (SNF).However,the co-existence of multi-valence states (Ⅳ/Ⅴ/Ⅵ) of Np and similar redox behavior with Pu(Ⅳ) hinder the effective separation of Np.N-Butyraldehyde (n-C_(3)H_(7)CHO) selectively reduces Np(Ⅵ) to Np(Ⅴ) without reducing Pu(Ⅳ).Herein,we examined the reduction mechanisms of Np(Ⅵ) and Pu(Ⅳ) by n-C3H7CHO using relativistic density functional theory.Based on the results of the potential energy profiles,the reductions of both Np(Ⅵ) and Pu(Ⅳ) by n-C_(3)H_(7)CHO are thermodynamically feasible,whereas only the former is kinetically achievable.It uncovers that n-C_(3)H_(7)CHO can only reduce Np(Ⅵ) to Np(Ⅴ) owing to kinetically controlled selective reduction.The analyses of spin density and bond distance indicate that the reduction nature for the first Np(Ⅵ)/Pu(Ⅳ) belongs to hydrogen atom transfer,whereas that for the second one involves outer-sphere electron transfer.Localized molecular orbitals (LMOs) analysis discloses the bonding evolution during the reduction process of Np(Ⅵ)/Pu(Ⅳ).This study elucidates the reason behind the kinetically controlled selective reduction of Np(Ⅵ)/Pu(Ⅳ) by nC3H7CHO at the molecular level and offers in-depth perspectives on the isolation of specific metal ions from the view of kinetic control. 展开更多
关键词 NEPTUNIUM PLUTONIUM reduction Density functional theory Kinetic control
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Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
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作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
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T-Pointer:A Chinese Text Semantic Extraction Model for Semantic Communication
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作者 Qian Liping Qian Jiang +3 位作者 Wu Wanwan Huang Liang Wu Yuan Yang Xiaoniu 《China Communications》 2026年第2期298-311,共14页
Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future... Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future sixth-generation(6G)wireless networks.In this paper,we propose a Chinese text semantic extraction model,namely T-Pointer,to improve the quality of semantic extraction by integrating the Transformer with the pointer-generator network.The proposed T-Pointer model consists of a semantic encoder and a semantic decoder.In the encoding stage,we use the multi-head attention mechanism of the Transformer to extract semantic features from the input Chinese text.In the decoding stage,we first use the Transformer to extract multi-level global text features.Then,we introduce the pointer-generator network model to directly copy the keyword information from the source text.The simulation results demonstrate that the T-Pointer model can improve the bilingual evaluation understudy(BLEU)and recalloriented understudy for gisting evaluation(ROUGE)by 14.69%and 14.87%on average in comparison with the state-of-the-art models,respectively.Also,we implement the T-Pointer model on a semantic communication system based on the universal software radio peripheral(USRP)platform.The result shows that the packet delay of semantic transmission can be reduced by 52.05%on average,compared to traditional information transmission. 展开更多
关键词 attention mechanism pointer-generator network semantic communication semantic extraction TRANSFORMER
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