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Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao Wu xingying Lan yi xiao College of Carbon Neutrality future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （f-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when f-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： Condensation reactions

Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-f18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： yi Liu JiuHou Lei fuQing Huang Su Zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program f18(DMSP-f18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

Spin-modulated near-infrared-Ⅰ emission in a xanthene-decorated fe(Ⅱ) spin-crossover complex

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Science China Chemistry 2025年

作者： Cheng yi Duyong Chen Shihui Zhang Rui Cai Chunying Duan yinshan Meng Tao Liu State Key Laboratory of fine Chemicals Frontier Science Center for Smart Materials and Chemical Engineering School of Chemical Engineering Dalian University of Technology Instrumental Analysis Center Dalian University of Technology School of Chemistry Dalian University of Technology Liaoning Binhai Laboratory

Molecular materials showing synergetic coupling of near-infrared （NIR） fluorescence and spin-crossover （SCO） are promisingly applicable in in-vivo bioimaging,temperature sensing,and spintronic *** the related study faces formidable *** this work we graft the NIR fluorophore xanthene onto the dipyridyl substituted triazole ligand and construct a new febased SCO material,{feⅡ（ddxc-abpt）2[N（CN）2]2}(1,ddxc-abpt:（E）-4-(((3,5-di（pyridin-2-yl）-4H-1,2,4-triazol-4-yl)imino)methyl)-N,N-diethyl-2,3-dihydro-1H-xanthen-6-amine).Magnetic studies indicate that compound 1 exhibits thermally induced SCO property in both the solid and solution ***-temperature fluorescence emission spectra reveal a remarkable 7-fold increase in photoluminescence intensity upon the transition from the low-spin state at 110 K to the high-spin state at 280 K,which is the record of all reported coupled fluorescence-SCO ***-temperature ultraviolet-visible （UV-Vis）absorption spectra show a significant change in absorption intensity within the fluorescence emission window,consistent with the f?rster resonance energy transfer （fRET） ***-dependent density functional theory （TD-DfT） calculations demonstrate that the strong coupling is attributed to disrupted energy transfer between the xanthene fluorophore and high-spin *** work provides a feasible approach for expanding the synergetic SCO-fluorescence materials to the NIR-Iwavelength region,and hopefully contributes to the applications of tunable NIR-SCO molecule-based sensors and devices.

关键词：

The Simultaneous fractional Dimension of Graph families

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1425-1441页

作者： Cong x.KANG Iztok PETERIN Eunjeong yi Texas A&M University at Galveston GalvestonTX 77553USA University of Maribor FEECS Smetanova 172000 MariborSlovenia

for a connected graph G with vertex set V,let RG{x,y}={z∈V:dG(x,z)≠dG(y,z)}for any distinct x,y∈V,where dG(u,w)denotes the length of a shortest uw-path in *** a real-valued function g defined on V,let g(V)=∑s∈V g(s).Let C={G_(1),G_(2),...,G_(k)}be a family of connected graphs having a common vertex set V,where k≥2 and|V|≥3.A real-valued function h:V→[0,1]is a simultaneous resolving function of C if h(RG{x,y})≥1 for any distinct vertices x,y∈V and for every graph G∈*** simultaneous fractional dimension,Sdf(C),of C is min{h(V):h is a simultaneous resolving function of C}.In this paper,we initiate the study of the simultaneous fractional dimension of a graph *** obtain max1≤i≤k{dimf(Gi)}≤Sd_(f)(C)≤min{∑k i=1 dimf(Gi),|V|/2},where both bounds are *** characterize C satisfying Sdf(C)=1,examine C satisfying Sdf(C)=|V|/2,and determine Sdf(C)when C is a family of vertex-transitive *** also obtain some results on the simultaneous fractional dimension of a graph and its complement.

关键词： Metric dimension fractional metric dimension resolving function simultaneous(metric)dimension simultaneous fractional(metric)dimension

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Ion motion effects on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration

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High Power Laser Science and Engineering 2014年第2期2卷 1-7页

作者： W.P.Wang x.M.Zhang x.f.Wang x.Y.Zhao J.C.xu Y.H.Yu L.Q.yi Y.Shi L.G.Zhang T.J.xu C.Liu Z.K.Pei B.f.Shen State Key Laboratory of High field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

The effects of ion motion on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration are investigated by analytical modeling and particle-in-cell simulations. Studies show that the rear part of the transmitted pulse modulated by ion motion is sharper compared with the case of the electron shutter only. In this study, the ions further modulate the short-cycle pulses transmitted. A 3.9 fs laser pulse with an intensity of 1.33×1021W cm-2is generated by properly controlling the motions of the electron and ion in the simulations. The short-cycle laser pulse source proposed can be applied in the generation of single attosecond pulses and electron acceleration in a small bubble regime.

关键词： radiation pressure acceleration short-cycle pulses particle-in-cell simulations.

Quantification of ventilation enhancement using the Eye CAN roof support

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International Journal of Mining Science and Technology 2017年第1期27卷 153-158页

作者： Shook Michael T Sindelar Mark f, Jiang Hua Luo yi Burrell Mining Products Inc.New KensingtonPA 15068USA Department of Mining Engineering West Virginia UniversityMorgantownWV 26506USA

Convergence of roof and floor in underground mine openings is a common occurrence. This convergence not only adversely affects the ability of workers, equipment and supplies to travel through the mine, it also reduces the effectiveness of the mine ventilation system, which is essential for the dilution of methane gas and airborne respirable dust. While installing secondary standing supports to control floor and roof convergence, such supports, by nature, partially obstruct a portion of the airway. These added obstructions inhibit the ability of the ventilation system to operate as efficiently as it could by increasing the resistance in and reducing the cross-sectional area of the airway. This study introduces and demonstrates the benefits of The Eye CAN^(TM) standing roof support, which controls floor and roof convergence and is less obstructive to air flow than conventional wooden cribs. Laboratory findings show that the normal resistance of a supported lined airway is reduced by using this new product from Burrell Mining Products, Inc., while providing the same roof support characteristics of an established product—The CANò. Load vs. displacement curves generated from laboratory tests demonstrated that this new product behaves with the same roof support characteristics as others in The CAN product family. Ventilation data gathered from a simulated mine entry was then used for computational fluid dynamics(CfD) *** CfD analysis showed an improvement with The Eye CAN vs. other accepted forms of standing roof support. This proof-of-concept study suggests that, when using this new product made by Burrell Mining Products, Inc., not only will the convergence from the roof and floor be controlled, but airway resistance will also be reduced.

关键词： Standing roof support CAN Ventilation Load-displacement Eye CAN

Langmuir-Schaefer film Investigation and Density functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong yi f L Supian A Radzwan M Musa N f N Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DfT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),fourier-transform infrared spectroscopy(fTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DfT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor

Satellite Measurements of the Madden–Julian Oscillation in Wintertime Stratospheric Ozone over the Tibetan Plateau and East Asia

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Advances in Atmospheric Sciences 2015年第11期32卷 1481-1492页

作者： ZHANG Yuli LIU yi LIU Chuanxi V.f.SOfIEVA Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Joint Center for Global Change Studies finnish Meteorological Institute

We investigate the Madden-Julian Oscillation （MJO） signal in wintertime stratospheric ozone over the Tibetan Plateau and East Asia using the harmonized dataset of satellite ozone profiles. Two different MJO indices -- the all-season Real-Time multivariate MJO index （RMM） and outgoing longwave radiation-based MJO index （OMI） -- are used to compare the MJO- related ozone anomalies. The results show that there are pronounced eastward-propagating MJO-related stratospheric ozone anomalies （mainly within 20-200 hPa） over the subtropics, The negative stratospheric ozone anomalies are over the Tibetan Plateau and East Asia in MJO phases 4-7, when MJO-related tropical deep convective anomalies move from the equatorial Indian Ocean towards the western Pacific Ocean. Compared with the results based on RMM, the MJO-related stratospheric column ozone anomalies based on OM1 are stronger and one phase ahead. further analysis suggests that different sampling errors, observation principles and retrieval algorithms may be responsible for the discrepancies among different satellite measurements. The MJO-related stratospheric ozone anomalies can be attributed to the MJO-related circulation anomalies, i.e., the uplifted tropopanse and the northward shifted westerly jet in the upper troposphere. Compared to the result based on RMM, the upper tropospheric westerly jet may play a less important role in generating the stratospheric column ozone anomalies based on OMI. Our study indicates that the circulation-based MJO index （RMM） can better characterize the MJO- related anomalies in tropopause pressure and thus the MJO influence on atmospheric trace gases in the upper troposphere and lower stratosphere, especially over subtropical East Asia.

关键词： Madden-Julian Oscillation stratospheric ozone tropopause subtropical jet stream

Structural and tectonothermal evolution of the ultrahigh-temperature Bakhuis Granulite Belt,Guiana Shield,Surinam:Palaeoproterozoic to recent

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Geoscience frontiers 2021年第2期12卷 677-692页

作者： frank f.Beunk Emond W.f.de Roever Keewook yi fraukje M.Brouwer faculty of Science Geology and Geochemistry ClusterVrije Universiteit Amsterdam(VUA)De Boelelaan 10851081HVAmsterdamthe Netherlands Division of Earth and Environmental Sciences Korean Basic Science InstituteOchang363-833South Korea

We constrain the multistage tectonic evolution of the Palaeoproterozoic UHT metamorphic(P=0.9–1.0 GPa,T>1000℃,t=2088–2031 Ma)Bakhuis Granulite Belt(BGB)in Surinam on the Guiana Shield,using large-to small-scale structures,Al-in-hornblende thermobarometry and published fluid inclusion and zircon geochronological *** BGB forms a narrow,NE–SW striking belt between two formerly connected,~E–W oriented granite-greenstone belts,formed between converging Amazonian and West African continental masses prior to collision and Transamazonian *** detrital zircon in BGB metasediments conforms agewise to Birimian zircon of West Africa and suggests derivation from the subsequently subducted African passive ***-temperature metamorphism may have followed slab break-off and asthenospheric heat *** metamorphic structures result from layer-parallel shearing and folding,reflecting initial transtensional exhumation of the subducted African margin after slab break-off.A second HT event involves intrusion,at ca.0.49 GPa,of charnockites and metagabbros at 1993–1984 Ma and a layered anorthosite at 1980 Ma,after the BGB had already cooled toxial bend in the new margin points northward towards the BGB and is likely the result of indentation by an anticlinorial flexural bulge of the subducting *** of the subducting oceanic plate along this bulge explains why the charnockites are restricted to the *** BGB subsequently experienced doming under an extensional detachment exposed in its southwestern border *** was focused in the BGB as a result of the flexural bulge in the subducting plate and localised heating of the overriding plate by charnockite *** present,straight NE–SW long-side boundaries of the BGB are superimposed mylonite zones,overprinted by pseudotachylites,previously dated

关键词： Bakhuis granulite belt Guiana shield Transamazonian orogeny UHT metamorphism Tectonics P-T-t evolution