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Tungsten 2025年第1期7卷 80-87页

作者： Fang-qian Wang Yin Zhang Wei-Wei Wang Mei-qian Fu Hong-Bing Mo Wei-Dong Yu chao Liu Jun Yan College of chemistry and chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[n（ch3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mech.nism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Worldvolume fermions as baryons in holographic quantum chromodynamics with instantons

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Communications in Theoretical Physics 2025年第1期77卷 106-121页

作者： Si-wen Li Hao-qian Li Yi-peng Zhang Department of Physics School of ScienceDalian Maritime UniversityDalian 116026China

In this study,we investigated worldvolume fermions on the flavor brane in the D0-D4/D8 model,which is holographically equivalent to four-dimensional quantum chromodynamics with instantons or equivalently with a theta *** action involving the worldvolume fermions was obtained by the T-duality rules in string theory,and we accordingly derived their effective five-dimensional and canonical four-dimensional forms by using the systematic dimensional reduction and decomposition of the ***,we used the AdS/CFT dictionary to evaluate the two-point correlation function as the spectral function for the worldvolume fermions and interpreted the fermions as baryons by analyzing their quantum number with the baryon vertex in *** this sense,the interacted action involving the worldvolume fermions and gauge field on the flavor brane was finally derived in holography,which describes the various interactions of mesons and baryons with instantons in the large-n ***,this study provides a holographic picture to describe baryons and their interactions based on string theory,particularly in the presence of instantons or a theta angle.

关键词： gauge-gravity duality AdS/CFT holographic QCD

2D copper-iron bimetallic metal-organic frameworks for reduction of nitrate with boosted efficiency and ammonia selectivity

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Journal of Environmental Sciences 2025年第3期149卷 374-385页

作者： qian Ma Yinghao Xue ch.ning Zhang Yanyan ch.n Wei Teng Hua Zhang Jianwei Fan State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China

Electrocatalytic reduction of nitrate to ammonia has been considered a promising and sustainable pathway for pollutant treatment and ammonia has significant potential as a clean ***,the method has received much *** this work,Cu/Fe 2D bimetallic metal-organic frameworks were synthesized by a facile method applied as cathode materials without high-temperature *** centers(Cu,Fe)with enhanced intrinsic activity demonstrated higher removal ***,the 2D nanosheet reduced themass transfer barrier between the catalyst and nitrate and increased the reaction ***,the catalysts with a 2D structure showed much better removal efficiency than other structures(3D MOFs and BulkMOFs).Under optimal conditions,Cu/Fe-2D MOF exhibited high nitrate removal efficiency(87.8%)and ammonium selectivity(89.3%)*** ammonium yielded up to significantly 907.2μg/(hr·mg_(cat))(7793.8μg/(hr·mg_(metal)))with Faradaic efficiency of 62.8%at an initial 100 mg n/*** catalyst was proved to have good stability and was recycled 15 times with excellent *** simulations confirm the reduced Gibbs free energy of Cu/Fe-2D *** study demonstrates the promising application of Cu/Fe-2D MOF in nitrate reduction to ammonia and provides new insights for the design of efficient electrode materials.

关键词： Metal-organic frameworks Electrochemical denitrification Ammonium selectivity 2D bimetal materials

Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 6-11页

作者： Haoyu Zhou Pang-chi Hsu Lin ch.n Yitian qian Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°n,150°E-150°W)and the subtropical northwestern Pacific(10°-20°n,130°E-175°W).The former is well-documented and considered to be influenced by the EnSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis *** elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget *** findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern *** increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective *** a process is pivotal in amplifying intraseasonal convection *** observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.

关键词： Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis

Copper-catalyzed C–C bond cleavage coupling with C≡n bond formation toward mild synthesis of lignin-based benzonitriles

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Journal of Environmental Sciences 2025年第5期151卷 505-515页

作者： Qi Luo Shenglong Tian qian qiang Fei song Wentao Su Haiyan He Qingda An ch.ngzhi Li Liaoning Key Lab of Lignocellulose chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of ch.nese Academy of Science Beijing 100049China

n-participated lignin depolymerization is of great importance for the transformation of waste lignin into value-added *** vast majority of developed strategies employ organic amines as nitrogen source,and considerablemethods rely on excessive use of strong base,which suffers severe environmental ***,benzonitrile derivatives are synthesized from oxidized ligninβ-O-4 model compounds in the presence of solid nitrogen source(nH_(4))_(2)CO_(3)under mild,base-free conditions over commercially available copper *** studies suggest the transformation undergoes a one-pot,highly coupled cascade reaction path involving oxidative C-C bond cleavage and in-situ formation of C≡n *** which,Cu(OAc)2 catalyzes the transfer of hydrogen from C_(β)(C_(β)-H)to C_(α),leading to the cleavage of C_(α)-C_(β)bonds to offer benzaldehyde derivative,this intermediate then reacts in-situ with(nH_(4))_(2)CO_(3)to afford the targeted aromatic nitrile *** iodide(TBAI),acting as a promoter,plays a key role in breaking the C_(α)-C_(β)bonds to form the intermediate benzaldehyde *** this protocol,the feasibility of the production of value-added syringonitrile from birchwood lignin has been *** transformation provides a sustainable approach to benzonitrile chemicals from renewable source of lignin.

关键词： Lignin β-O-4 model compounds Benzonitrile derivatives Copper catalyst Mild conditions

Effect of pouring time on microstructure and mech.nical properties of centrifugal cast Ti-46Al alloy tubes

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ch.na Foundry 2025年第1期22卷 65-74页

作者： Gang Huang qian Dang Cong-cong Su Jing Zhao chi Zhang Guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mech.nical *** this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was *** research comprehensively examined the influence of pouring time on the microstructure and mech.nical performance of the castings,employing both experimental approaches and ProCast simulation *** findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed *** the condition of pouring temperature of 1,600℃,rotation speed of 800 r·min^(-1) and pouring time of 6 s,the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa,and the tensile strength at 800℃ reaches 705 MPa,which is significantly higher than that of traditional as-cast Ti-Al alloy.

关键词： vacuum induction melting centrifugal casting Ti-46Al alloy pouring time Ti-Al alloy tubes

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Introducing strong metal–oxygen bonds to suppress the Jahn-Teller effect and enhance the structural stability of ni/Co-free Mn-based layered oxide cathodes for potassium-ion batteries

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Journal of Energy chemistry 2025年第2期101卷 713-722页

作者： Yich.ng Lin Shaohua Luo Pengyu Li Jun Cong Wei Zhao Lixiong qian Qi Sun Shengxue Yan School of Materials Science and Engineering Northeastern University School of Resources and Materials Northeastern University at Qinhuangdao Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province

Mn-based layered oxides（KMO） have emerged as one of the promising low-cost cathodes for potassiumion batteries（PIBs）.However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the Jahn-Teller（JT） effect associated with Mn-ion,the cathode exhibits poor structural ***,we propose a strategy to enhance structural stability by introducing robust metal-oxygen（M-O） bonds,which can realize the pinning effect to constrain the distortion in the transition metal（TM） ***,all the elements employed have exceptionally high crustal *** a proof of concept,the designed K0.5Mn0.9Mg0.025Ti0.025Al0.05O2cathode exhibited a discharge capacity of approximately 100 mA h g-1at 20 mA g-1with 79% capacity retention over 50 cycles,and 73% capacity retention over 200 cycles at 200 mA g-1,showcased much better battery performance than the designed cathode with less robust M-O *** properties of the formed M-O bonds were investigated using theoretical *** enhanced dynamics,mitigated JT effect,and improved structural stability were elucidated through the in-situ X-ray diffractometer（XRD）,in-situ electrochemical impedance spectroscopy（EIS）(and distribution of relaxation times（DRT） method),and ex-situ X-ray absorption fine structure（XAFS） *** study holds substantial reference value for the future design of costeffective Mn-based layered cathodes for PIBs.

关键词： Jahn-Teller effect Layered oxide cathodes Low-cost Potassium-ion batteries Robust M–O bonds

Synergistically enhanced ORR and HER performance on Co-n-C coupled in-situ generated PtCo intermetallic

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Journal of Energy chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An Xiao Huang qian Zhang ch.nhao Zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material chemistry for Energy Conversion and Storage(Huazhong University of Science and Technology)Ministry of Education School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds (IMCs)(o-PtCo@ConC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a ch.nce for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@ConC exhibits excellent electrocatalytic performance for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) with mass activity of 1.21 A mgPt-1(at 0.9 V) and5.70 A mgPt-1(at an overpotential of 100 mV),***,o-PtCo@ConC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Synergistic effect Intermetallics Single atomic sites Oxygen reduction reaction Hydrogen evolution reaction

Prediction of specific spoilage organisms in smoked chicken legs with modified atmosphere packaging at 4℃ using multivariate statistical analysis

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Food Science and Human Wellness 2025年第1期14卷 271-281页

作者： qiang Wang Yubo Zhao Yumeng Sui qian ch.n Zhiming Dong qian Liu Baohua Kong Ligang Qin College of Food Science Northeast Agricultural UniversityHarbin 150030China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030China

The present study monitored bacterial succession,physicochemical properties,and volatile organic compounds(VOCs)ch.nges in smoked chicken legs with modified atmosphere packaging(MAP,60% CO_(2) and 40%n_(2))during a 25-day storage period at 4℃.After 15 days of storage,S erratia proteamaculans and Pseudomonas fragi became the predominant ***,physicochemical properties ch.nged significantly,as evidenced by an increase in thiobarbituric acid reactive substances and b*(yellowness)value,and a decrease in hardness.A total of 65 VOCs were identified during *** between bacterial succession and quality indicators(including VOCs and physicochemical properties)allowed the identification of 26 core dominant bacteria,including ***,Psychrobacter alimentarius,Pseudomonas putida,and Pseudomonas poae,which were positively related to spoilage VOCs(e.g.,1-octen-3-ol,1-pentanol,and 3-methyl-1-butanol)and could be defined as specific spoilage organisms(SSOs).The results of this study provide a systematic approach to predict SSOs in smoked chicken legs during storage,which can also provide a basis for product safety.

关键词： Smoked chicken legs Modified atmosphere packaging Bacterial community Volatile organic compounds Specific spoilage organisms

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Efficient continuous synthesis of 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermediate of Triflumezopyrim,coupling with esterification-condensation-hydrolysis

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ch.nese chemical Letters 2025年第1期36卷 234-238页

作者： Yuexiang Liu Xiangqiao Yang Tong Lin Guantian Yang Xiaoyong Xu Bubing Zeng Zhong Li Weiping Zhu Xuhong qian Shanghai Key Laboratory of chemical Biology School of PharmacyEast China University of Science and TechnologyShanghai 200237China Shanghai Frontiers Science Center of Optogenetic Techniques for Cexll Metabolism School of PharmacyEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Engineering Research Center of Pharmaceutical Process chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Green chemistry and chemical Processes Department of ChemistrySchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200241China

Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n Ach Rs)and has no cross-resistance with other ***,we firstly developed a new continuous flow approach to synthesis 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermate of TFM,coupling with esterification,condensation,and *** three-step reactions were optimized and transformed into a continuous synthesis mode by three micro reaction *** with the batch mode,the total reaction time and overall separation yield were improved from more than 12 h and 60%to 18 min and 73.38%,*** solvent consumption and waste emission were significantly reduced,which also provides an eco-friendly and efficient potential tool for the development and production of mesoionic pyrido[1,2-α]pyrimidinones insecticide.

关键词： Triflumezopyrim(TFM) 2-[3-(Trifluoromethyl)phenyl]malonic acid Continuous flow synthesis Micro-reactor