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Journal of Environmental Sciences 2024年第7期141卷 314-329页

作者： Komal Daya Soni Khem Singh Shankar G.Aggarwal csir-national physical laboratory Dr.K.S.Krishnan MargNew Delhi 110012India Academy of Scientific&Innovative Research(Acsir) Ghaziabad 201002India

Vehicular emissions are considered one of the major anthropogenic sources of greenhouse gases and poor air quality in metropolitan *** study aims to see the correlation of CO_(2),CH_(4),and CO through monitoring over a period from December 2020 to October 2021 covering three seasons’winter,summer,and monsoon at two different traffic locations of Delhi having different traffic volumes,road patterns,and traffic *** annual average morning concentration of CO_(2),CH_(4)and CO was found(533±105),(7.3±3.1),(10.7±3.0)ppm at Najafgarh and(480±70),(5.2±1.8),(7.8±2.8)ppm at Rajendra Place,respectively.A relationship between concentration of all three gases and meteorological parameters such as temperature,humidity,wind speed and wind direction has also been investigated using Pearson correlation coefficient and pollution rose diagram.A comparable pattern in concentration was observed for all three gases in spatial(location)and temporal(diurnal)*** concentration trend of CO_(2)in different seasons is winter>summer>monsoon,while in the case of CH_(4)winter=summer>monsoon but not any seasonal trend was noted in CO *** is observed that CO_(2)has a good relation with CO(a tracer for vehicular emission)in terms of diurnal variation,whereas,CH_(4)does not represent a relation with CO and CO_(2)diurnally,suggesting that vehicles are the source of CO_(2)but not much contributing to other greenhouse gases like CH_(4).

关键词： Vehicular emission Greenhouse gases Harmful pollutants Meteorological parameters

Holevo bound independent of weight matrices for estimating two parameters of a qubit

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Chinese Physics B 2024年第2期33卷 137-143页

作者：牛畅郁司夏 Department of Modern Physics&Hefei national Research Center for physical Sciences at the Microscale and School of physical Sciences University of Science and Technology of ChinaHefei 230026China Hefei national laboratory University of Science and Technology of ChinaHefei 230088China

Holevo bound plays an important role in quantum metrology as it sets the ultimate limit for multi-parameter estimations,which can be asymptotically *** for some trivial cases,the Holevo bound is implicitly defined and formulated with the help of weight *** we report the first instance of an intrinsic Holevo bound,namely,without any reference to weight matrices,in a nontrivial ***,we prove that the Holevo bound for estimating two parameters of a qubit is equivalent to the joint constraint imposed by two quantum Cramér–Rao bounds corresponding to symmetric and right logarithmic *** weightless form of Holevo bound enables us to determine the precise range of independent entries of the mean-square error matrix,i.e.,two variances and one covariance that quantify the precisions of the estimation,as illustrated by different estimation *** result sheds some new light on the relations between the Holevo bound and quantum Cramer–Rao *** generalizations are discussed.

关键词： quantum metrology quantum Fisher information Holevo bound quantum multi-parameter estimation

“Buckets effect”in the kinetics of electrocatalytic reactions

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Journal of Energy Chemistry 2024年第2期89卷 388-396,I0010页

作者： Haowen Cui Yan-Xia Chen Hefei national laboratory for physical Sciences at Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

In this study,we systematically investigated the effect of proton concentration on the kinetics of the oxygen reduction reaction(ORR)on Pt(111)in acidic *** results demonstrate a rectangular hyperbolic relationship,i.e.,the ORR current excluding the effect of other variables increases with proton concentration and then tends to a constant *** consider that this is caused by the limitation of ORR kinetics by the trace oxygen concentration in the solution,which determines the upper limit of ORR kinetics.A model of effective concentration is further proposed for rectangular hyperbolic relationships:when the reactant concentration is high enough to reach a critical saturation concentration,the effective reactant concentration will become a constant *** could be due to the limited concentration of a certain reactant for reactions involving more than one reactant or the limited number of active sites available on the *** study provides new insights into the kinetics of electrocatalytic reactions,and it is important for the proper evaluation of catalyst activity and the study of structureperformance relationships.

关键词： Oxygen reduction reaction Kinetics Zero order Rectangular hyperbolic relationship pH effect

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

Experimental Proposal on Non-Hermitian Skin Effect by Two-dimensional Quantum Walk with a Single Trapped Ion

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Chinese Physics Letters 2024年第4期41卷 19-24页

作者：侯琬儿唐皓许勤林毅恒 CAS Key laboratory of Microscale Magnetic Resonance and School of physical Sciences University of Science and Technology of ChinaHefei 230026China Hefei national laboratory University of Science and Technology of ChinaHefei 230088China

Non-Hermitian Hamiltonians are widely used in describing open systems with gain and loss,among which a key phenomenon is the non-Hermitian skin *** we report an experimental scheme to realize a twodimensional(2D)discrete-time quantum walk with non-Hermitian skin effect in a single trapped *** is shown that the coin and 2D walker states can be labeled in the spin of the ion and the coherent-state lattice of the ion motion,*** numerically observe a directional bulk flow,whose orientations are controlled by dissipative parameters,showing the emergence of the non-Hermitian skin *** then discuss an experimental implementation of our scheme in a laser-controlled trapped Ca^(+)*** experimental proposal may be applicable to research of dissipative quantum walk systems and may be able to generalize to other platforms,such as superconducting circuits and atoms in cavity.

关键词： effect dissipative quantum

Regulating atomic Fe-Rh site distance for efficient oxygen reduction reaction

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Science China Chemistry 2024年第4期67卷 1352-1359页

作者： Tong Liu Yudan Chen Airong Xu Xiaokang Liu Dong Liu Sicheng Li Hui Huang Li Xu Shuaiwei Jiang Qiquan Luo Tao Ding Tao Yao national Synchrotron Radiation laboratory University of Science and Technology of ChinaHefei 230029China Key laboratory of Precision and Intelligent Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institutes of physical Science and Information Technology Anhui UniversityHefei 230601China

Exploring the atomic interaction mechanisms of dense single-atom catalysts(SACs)is of great significance for their application in oxygen reduction reaction(ORR).However,the intrinsic mechanism of the site-distance effect on the catalytic performance has been largely ***,we demonstrate the site-distance effect of Fe-Rh_(x)@NC catalysts in ORR theoretically and *** charge analysis reveals that the strong interaction between Fe and Rh atoms at a certain atomic distance(dFe-Rh)alters the catalytic electronic structure,facilitating the optimization of catalyst adsorption *** by the theoretical calculations,we designed and synthesized the Fe-Rhx@NC catalysts through a spatial confinement *** characterization results prove that the Fe-Rh_(2)@NC has the optimal d_(Fe-Rh),which improves its intrinsic ORR activity,providing a half wave potential of 0.91 V,higher than that of the commercial Pt/C(0.86 V).This study emphasizes the importance of determining the basic mechanism of the site-distance effect in dissimilar metal atoms catalysts,which is conducive to the design of efficient catalyst systems for practical applications.

关键词： Density functional theory single-atom catalyst in-situ encapsulating site-distance effect oxygen reduction reaction

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Overcoming the Na-ion conductivity bottleneck for the cost-competitive chloride solid electrolytes

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Journal of Energy Chemistry 2024年第8期95卷 1-8,I0001页

作者： Lv Hu Hui Li Fang Chen Yating Liu Jinzhu Wang Cheng Ma Hefei national Research Center for physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026AnhuiChina national Synchrotron Radiation laboratory Hefei 230026AnhuiChina

Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or ***,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)*** addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid *** combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.

关键词： All-solid-state sodium batteries Ionic conductivities Solid electrolytes Chlorides High voltage stability

Double stimulus-responsive palladium catalysts for ethylene polymerization and copolymerization

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Chinese Chemical Letters 2024年第7期35卷 407-411页

作者： Hailong He Wenbing Wang Wenmin Pang Chen Zou Dan Peng CAS Key laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei National Laboratory for Physical Sciences at the MicroscaleHefei 230026China

The external stimulus response strategy has been evolved rapidly in the field of olefin *** this work,we modularly synthesized three types of double stimulus responsiveα-diimine palladium catalysts,combining redox regulation and other regulation together,such as light,Lewis acid and alkali *** catalytic activities and the molecular weight of polyethylene products can be regulated for 4 times in ethylene *** palladium complexes were also used for the copolymerization reaction of ethylene and polar monomers,such as methyl 10-undecylenate and methyl acrylate,effectively regulating the catalytic activities,the molecular weight and polar monomer incorporation of the prepared *** research on these dual-regulated palladium complexes makes full use of prepared catalysts and provides new inspirations for regulating olefin polymerization.

关键词： Dual-regulated Stimulus-responsive Palladium Ethylene polymerization Polar monomer

High-rate CH_(4)-to-C_(2)H_(6) photoconversion enabled by Au/ZnO porous nanosheets under oxygen-free system

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Science China Chemistry 2024年第3期67卷 869-875页

作者： Kai Zheng Xiaojing Zhang Jun Hu Chengbin Xu Juncheng Zhu Jing Li Mingyu Wu Shan Zhu Li Li Shumin Wang Yumei Lv Xin He Ming Zuo Chengyuan Liu Yang Pan Junfa Zhu Yongfu Sun Yi Xie Hefei national laboratory for physical Sciences at Microscale National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Key laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China State Grid Anhui Electric Power Research Institute Hefei 230601China

Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still ***,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling *** an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported *** virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.

关键词： dual surface-active sites selective methane coupling ethane room temperature

Comparative study on phase transition behaviors of fractional molecular field theory and random-site Ising model

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Chinese Physics B 2024年第3期33卷 536-541页

作者：刘婷玉赵薇王涛安小冬卫来黄以能 Xinjiang laboratory of Phase Transitions and Microstructures in Condensed Matters College of Physical Science and TechnologyYili Normal UniversityYili 835000China national laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210008China

Fractional molecular field theory(FMFT)is a phenomenological theory that describes phase transitions in crystals with randomly distributed components,such as the relaxor-ferroelectrics and spin *** order to verify the feasibility of this theory,this paper fits it to the Monte Carlo simulations of specific heat and susceptibility versus temperature of two-dimensional(2D)random-site Ising model(2D-RSIM).The results indicate that the FMFT deviates from the 2D-RSIM *** main reason for the deviation is that the 2D-RSIM is a typical system of component random distribution,where the real order parameter is spatially heterogeneous and has no symmetry of space translation,but the basic assumption of FMFT means that the parameter is spatially uniform and has symmetry of space translation.

关键词： phase transition molecular field theory Ising model Monte Carlo