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Fine particle trace elements at a mountain site in southern China:Source identification,transport,and health risks

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Journal of Environmental Sciences 2024年第7期141卷 166-181页

作者： Jiaoping xing Runping Ding Feifeng Chen Linyu Peng Wenhua wang Xiaoyan Song Qing Ye Yuanqiu Liu Key Laboratory of State Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed School of ForestryJiangxi Agricultural UniversityNanchang 330045China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China College of Geosciences and Engineering North China University of Water Resources&Electric PowerZhengzhou 450046China

Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical *** this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples collected at the summit of *** were analyzed to quantify their abundance,source,transport,and health *** the whole sampling period,the major trace elements was Ca,Al,and *** the trace metals with the lowest concentrations were Sr,Ni,Rb,and *** trace elements were influenced by air mass transport routes,exhibiting an increasing trend of crustal elements in the northwesterly airmass and anthropogenic elements(Zn,Mn,Cu,and Ni)in the easterly air *** dust,coal+biomass burning,vehicle emission,urban nitrate-rich+urban waste incineration emissions,and soil dust+industry emissions were common sources of PM2.5on *** air mass transport routes had various source contribution *** results indicate that trace elements at *** are influenced by regional anthropogenic emissions and monsoon-dominated trace element *** total resulting cancer risk value that these elements posed were below the acceptable risk value of 1×10^(-6),while the non-carcinogenic risk value(1.72)was higher than the safety level,suggesting that non-carcinogenic effects due to these trace elements inhalation were likely to *** emission and coal+biomass burning were the common dominant sources of non-cancer risks posed by trace elements at ***.

关键词： Trace elements Risk assessment Cluster analysis Source apportionment

Super-resolution diffractive neural network for alloptical direction of arrival estimation beyond diffraction limits

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Light(Science & Applications) 2024年第8期13卷 1602-1614页

作者： Sheng Gao Hang Chen Yichen wang Zhengyang Duan Haiou Zhang Zhi Sun Yuan Shen xing Lin Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication,radar,navigation,***,the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process,which places the fundamental limit on its sensing speed and energy ***,we propose the super-resolution diffractive neural networks(S-DNN)to process electromagnetic(EM)waves directly for the DOA estimation at the speed of *** multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction *** spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of *** S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in *** results achieve the angular resolution over an order of magnitude,experimentally demonstrated with four times,higher than diffraction-limited *** also apply S-DNN’s edge computing capability,assisted by reconfigurable intelligent surfaces,for extremely low-latency integrated sensing and communication with low power *** work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

关键词： beyond optical network

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-Ming An Yi-Ping wang Tang-Song Zhu Chong xing Xu-Dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

Low-firing and temperature stability regulation of tri-rutile MgTa_(2)O_(6)microwave dielectric ceramics

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1935-1943页

作者： Chengzhi Xu Hongyu Yang Hongcheng Yang Linzhuang xing Yuan wang Zhimin Li Enzhu Li Guorui Zhao School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China National Engineering Research center of Electromagnetic Radiation Control Materials and Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of ChinaChengdu 610054China Songshan Lake Materials Laboratory A1 Building University Innovation ParkDongguan 523808China

A glass frit containing Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)component was used to explore the low-temperature sintering behaviors and microwave dielectric characteristics of tri-rutile MgTa_(2)O_(6)ceramics in this *** good low-firing effects are presented due to the high matching relevance between Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass and MgTa_(2)O_(6)*** pure tri-rutile MgTa_(2)O_(6)structure remains unchanged,and high sintering compactness can also be achieved at 1150℃.We found that the Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass not only greatly improves the low-temperature sintering characteristics of MgTa_(2)O_(6)ceramics but also maintains a high(quality factor(Q)×resonance frequency(f))value while still improving the temperature ***,great microwave dielectric characteristics when added with 2wt%Li_(2)O-MgO-ZnO-B_(2)O_(3)-SiO_(2)glass can be achieved at 1150℃:dielectric constant,ε_(r)=26.1;Q×f=34267 GHz;temperature coefficient of resonance frequency,τ_(f)=-8.7×10^(-6)/℃.

关键词： MgTa_(2)O_(6) ceramic microwave dielectric characteristics glass

Enhancing thermoelectric performance of p-type SnTe through manipulating energy band structures and decreasing electronic thermal conductivity

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Rare Metals 2024年第7期43卷 3232-3241页

作者： Xin Qian Hao-Ran Guo Jia-Xin Lyu Bang-Fu Ding xing-Yuan San Xiao Zhang Jiang-Long wang Shu-Fang wang Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China College of Electron and Information Engineering Hebei UniversityBaoding 071002China Research Institute for Frontier Science Beihang UniversityBeijing100191China

SnTe has received considerable attention as an environmentally friendly alternative to the representative thermoelectric material of ***,excessive hole carrier concentration in SnTe results in an extremely low Seebeck coefficient and high thermal conductivity,which makes it exhibit relatively inferior thermoelectric *** this work,the thermoelectric performance of p-type SnTe is enhanced through regulating its energy band structures and reducing its electronic thermal conductivity by combining Bi doping with CdSe ***,the carrier concentration of SnTe is successfully suppressed via Bi doping,which significantly decreases the electronic thermal ***,the convergence and flattening of the valence bands by alloying CdSe effectively improves the effective mass of SnTe while restraining its carrier ***,a maximum figure of merit(ZT) of~ 0.87 at 823 K and an average ZT of~ 0.51 at 300-823 K have been achieved in Sn_(0.96)Bi_(0.04)Te-5%*** results indicate that decreasing the electronic thermal conductivity is an effective means of improving the performance of thermoelectric materials with a high carrier concentration.

关键词： Thermoelectric materials SnTe Energy band structure Electronic thermal conductivity ZT value

Interfacial Oxygen Octahedral Coupling-Driven Robust Ferroelectricity in Epitaxial Na_(0.5)Bi_(0.5)TiO_(3)Thin Films

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Research 2024年第2期2023卷 149-157页

作者： Haojie Han Qinghua Zhang Wei Li Yiqun Liu Jiasheng Guo Yue wang Qian Li Lin Gu ce-Wen Nan Jing Ma State Key Laboratory of New ceramics and Fine Processing Schoolof Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

The oxygen octahedral rotation(OOR)forms fundamental atomic distortions and symmetries in perovskite oxides and definitely determines their properties and ***,epitaxial strain and interfacial structural coupling engineering have been developed to modulate the OOR patterns and explore novel properties,but it is difficult to distinguish the 2 ***,different symmetries are induced in Na_(0.5)Bi_(0.5)TiO_(3)(NBT)epitaxial films by interfacial oxygen octahedral coupling rather than epitaxial *** NBT film grown on the Nb:SrTiO_(3)substrate exhibits a paraelectric tetragonal phase,while with La_(0.5)Sr_(0.5)MnO_(3)as a buffer layer,a monoclinic phase and robust ferroelectricity are obtained,with a remanent polarization of 42μC cm^(-2)and a breakdown strength of 7.89 MV cm^(-1),which are the highest record among NBT-based ***,the interfacial oxygen octahedral coupling effect is demonstrated to propagate to the entire thickness of the film,suggesting an intriguing long-range *** work provides a deep insight into understanding the structure modulation in perovskite heterostructures and an important avenue for achieving unique functionalities.

关键词： effect. interfacial coupling

Stabilizing high-efficiency iridium single atoms via lattice confinement for acidic oxygen evolution

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Nano Research 2024年第4期17卷 2492-2498页

作者： Yibo wang Jiadong Jiang Zhaoping Shi Hongxiang Wu Jiahao Yang Pengbo wang Shuai Hou Meiling Xiao Junjie Ge Changpeng Liu Wei xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026.China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Jilin Province Key Laboratory of Low Carbon Chemical Power Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Physics and Technology for Advanced Batteries Ministry of EducationCollege of PhysicsJilin UniversityChangchun 130012China

Stable and efficient single atom catalysts(SACs)are highly desirable yet challenging in catalyzing acidic oxygen evolution reaction(OER).Herein,we report a novel iridium single atom catalyst structure,with atomic Ir doped in tetragonal PdO matrix(IrSAs-PdO)via a lattice-confined *** optimized IrSAs-PdO-0.10 exhibited remarkable OER activity with an overpotential of 277 mV at 10 mA·cm^(-2) and long-term stability of 1000 h in 0.5 M H_(2)SO_(4).Furthermore,the turnover frequency attains 1.6 s^(-1) at an overpotential of 300 mV with a 24-fold increase in the intrinsic *** high activity originates from isolated iridium sites with low valence states and decreased Ir–O bonding covalency,and the excellent stability is a result of the effective confinement of iridium sites by Ir–O–Pd ***,we demonstrated for the first time that SACs have great potential in realizing ultralow loading of iridium(as low as microgram per square center meter level)in a practical water electrolyzer.

关键词： lattice confinement iridium single atoms ultralow iridium loading acidic oxygen evolution proton exchange membrane water electrolysis

Performance Analysis of an Efficient Integration System of Coal-Fired Power Plant,Solar Thermal Energy and CO_(2)Capture

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Journal of Thermal Science 2024年第4期33卷 1509-1522页

作者： wang Yuhao wang Ruilin LIU Lanhua xing Chenjian GUO Yafei YANG Qingshan YING Jiaheng SUN Jian LI Wenjia LIU Yuanyuan ZHAO Chuanwen School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing210023China China Huadian Group Co.LTD.Shanghai Branch Shanghai200120China Key Laboratory of Efficient Utilization of Low and Medium Grade Energy(Tianjin University) Ministry of Education of ChinaTianjin300350China Huadian Zhengzhou Mechanical Design Institute Company Limited Zhengzhou450046China

Coal-fired power plant is a major contributor to greenhouse gas *** post-combustion capture is a promising method for CO_(2)emission reduction but the high thermal demand is *** address this issue,solar thermal energy and CO_(2)capture are jointly integrated into the coal-fired power plant in this *** solar thermal energy is employed to meet the heat requirement of the CO_(2)capture process,thereby avoiding the electricity loss caused by self-driven CO_(2)***,the heat released from the carbonation reaction of MgO adsorbent is integrated into the steam Rankine *** partially substituting the extracted steam for feedwater heating,the electricity output of the power plant is further *** to the results from the developed model,the system could achieve a CO_(2)capture rate of 86.5%and an electricity output enhancement of 9.8%compared to the reference system,which consists of a self-driven CO_(2)capture coal-fired power plant and PV generation *** operational strategy is also optimized and the amount of CO_(2)emission reduction on a typical day is increased by 11.06%.This work shows a way to combine fossil fuels and renewable energy for low carbon emissions and efficient power generation.

关键词： CO_(2)capture parabolic trough collector solar aided coal-fired electricity generation

Pd Pt VO_(x)/ceO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

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Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： Jia wang Yuxi Liu Jiguang Deng Lin Jing Xiuqing Hao xing Zhang Xiaohui Yu Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/ceO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance