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Chinese Journal of Chemical Engineering 2024年第2期66卷 136-144页

作者： Chenggong Song Zhenzhou Ma Xu Hou hao Zhou Huimin Qiao Changchang Tian Li Yin Baitang Jin Enxian yuan School of Chemical Engineering Changchun University of TechnologyChangchun130012China Department of Chemical and Biomolecular Engineering North Carolina State UniversityRaleighNC 27606USA School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225009China

High-temperature treatment is key to the preparation of zeolite ***,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid ***,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke *** on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.

关键词： HZSM-5 n-heptane Catalytic cracking High-temperature treatment Extra-framework Al

Highly coupled off-resonance lattice design in diffraction-limited light sources

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Nuclear Science and Techniques 2024年第9期35卷 92-102页

作者： Yi-hao Gong Shun-Qiang Tian Xin-Zhong Liu Shou-Zhi Xuan Li-yuan Tan Ling-Long Mao Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 ShanghaiChina Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 ShanghaiChina University of Chinese Academy of Sciences 100049 BeijingChina

The round-beam operation presents many benefits for scientific experiments regarding synchrotron radiation and the weak-ening influences of intra-beam scattering in diffraction-limited synchrotron light sources.A round-beam generation method based on the global setting of skew quadrupoles and the application of a non-dominated sorting genetic algorithm was pro-posed in this *** schemes,including large-emittance coupling introduced via betatron coupling and vertical disper-sion,were explored in a candidate lattice for an upgrade-proposal of the Shanghai synchrotron radiation *** variations with lattice imperfections and their influence on the beam dynamics of beam optic distortions were *** results demonstrated that a precise coupling control ranging from 10 to 100%was achieved under low optical distortion,whereas full-coupling generation and its robustness were achieved by our proposed method by adjusting the skew quadrupole components located in the dispersion-free *** Touschek lifetime increased by a factor of 2–2.5.

关键词： Diffraction-limited storage ring(DLSR) Shanghai synchrotron radiation facility upgrade(SSRF-U) Round beam Off-resonance coupling

Attenuation of blast-induced vibration on tunnel structures

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Geohazard Mechanics 2024年第3期2卷 153-163页

作者： Xiao Wang Xiaofeng Hou Wei yuan Changdi he Vahab Sarfarazi hao Fan College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine Anhui University of Science and TechnologyHuainanAnhui 232001China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China School of Civil Engineering Southeast UniversityNanjing211189China Department of Mining Engineering University of UtahSalt Lake CityUT84112USA Department of Mining Engineering Hamedan University of TechnologyHamedanIran

The blast-induced vibration during excavation by drilling and blasting method has an important impact on thesurrounding structures. In particular, with the development of tunnel engineering, the impact of blasting vibrationon tunnel construction has attracted extensive attention. In this paper, the propagation attenuation characteristicsof blast-induced vibration (PPV, peak particle velocity) on different tunnel structures were systematically studiedbased on the ﬁeld monitoring data. Initially, the attenuation characteristics of blasting vibration PPV on the lowerbench surface, the side wall of the excavated tunnel and the closely spaced adjacent tunnel were ***, the capacity of several widely utilized empirical prediction equations to estimate the PPV on tunnelstructures was examined, along with a comparative analysis of their prediction accuracy. The research ﬁndingsindicate that it is feasible to predict the PPV on the tunnel structures using empirical equations. The attenuationcharacteristics of blasting vibration PPV are different in different structures and directions. The prediction accuracy of the empirical equations varies, while the discrepancies are minimal. The principal variation amongthese equations lies in the site-speciﬁc coefﬁcients k, β, λ, highlighting the differential impact of structural anddirectional considerations on the predictive efﬁcacy. Based on the empirical equation and safe PPV provided bythe blasting vibration safe standards on tunnels of China (GB6722-2014), and considering the inﬂuence of allstructures and directions, it is determined that the safe distance of blasting vibration in the tested tunnel projectshould be larger than 20.28–18.31 m, 18.31–16.16 m, and 16.16–13.75 m for blasting vibration frequency locatedin 10 Hz, 10–50 Hz, and >50 Hz.

关键词： Blast-induced vibration Tunnel structures PPV Empirical equations Prediction accuracy Safe distance

Theoretical study of superradiant masing with solid-state spins at room temperature

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 38-47页

作者： Qilong Wu yuan Zhang hao Wu Shi-Lei Su Kai-Kai Liu Mark Oxborrow Chong-Xin Shan Klaus Mølmer henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China Center for Quantum Technology Research and Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements School of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing Academy of Quantum Information Sciences Beijing 100193China Department of Materials Imperial College LondonLondon SW72AZUK Niels Bohr Institute University of CopenhagenCopenhagen 2100Denmark

Steady-state superradiance and superradiant lasing attract significant attentions in the field of optical lattice clocks,but have not been achieved yet due to the technical challenges and atom loss *** this article,we propose that their counter-part may be observed in the microwave domain with solid-state spins,i.e.,nitrogen-vacancy center spins and pentacene molecular spins,coupled to microwave resonator at room temperature with realistic technical *** validate our proposal,we investigate systematically the system dynamics and steady-state by solving quantum master equations for the multi-level and multi-process dynamics of trillions of *** calculations show that the superradiant Rabi oscillations occur firstly due to transitions among different Dicke states,and the subsequent continuous-wave superradiant masing can achieve a linewidth well below *** work may guide further exploration of transient and steady-state superradiant masing with the mentioned and other solid-state spins *** ultra-narrow linewidth may find applications in deep-space communications,radio astronomy and high-precision metrology.

关键词： solid-state spins superradiance maser

Experimental observation of the significant difference between surface and bulk Kondo processes in Kondo lattice YbCu_(2)Si_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 154-160页

作者： Yin-Zou Zhao Jiao-Jiao Song Qi-Yi Wu hao Liu Chen Zhang Bo Chen Hong-Yi Zhang Zhen-Hua Chen Yao-Bo Huang Xue-Qing Ye Ya-Hua yuan Yu-Xia Duan Jun he Jian-Qiao Meng School of Physics Central South UniversityChangsha 410083China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China

Synchrotron-based angle-resolved photoemission spectroscopy was employed to investigate the temperature evolution of the Yb 4 f spectral for surface and bulk in the Kondo lattice YbCu_(2)Si_(2).Our study quantitatively distinguishes between the surface and bulk hybridization processes,revealing that the onset temperatures for both surface and bulk hybridization processes are significantly higher than the Kondo ***,we found that the effective surface Kondo temperature is much lower than that of the *** findings offer valuable insights into the understanding of heavy fermion physics.

关键词： Kondo lattice angle-resolved photoemission spectroscopy electronic structure hybridization surface state

PDCD2 as a prognostic biomarker in glioma correlates with malignant phenotype

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Genes & Diseases 2024年第5期11卷 390-406页

作者： Fengsheng Dai Yixiao yuan Jiaqi hao Xing Cheng Xiangyi Zhou Li Zhou Rui Tian Yi Zhao Tingxiu Xiang Department of Oncology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China Department of Neurosurgery Xiangya HospitalCentral South UniversityChangshaHunan 410008China Hunan International Scientific and Technological Cooperation Base of Brain Tumor Research Xiangya HospitalCentral South UniversityChangshaHunan 410008China Department of Neuro-Oncology Chongqing University Cancer HospitalChongqing 400030China

Programmed cell death 2(PDCD2)is related to cancer progression and chemotherapy *** role of PDCD2 in solid cancers(excluding hematopoietic malignancies)and their diagnosis and prognosis remains *** TCGA,CGGA,GEPIA,cBioPortal,and GTEx databases were analyzed for expression,prognostic value,and genetic modifications of PDCD2 in cancer *** enrichment analysis,CCK8,colony formation assay,transwell assay,and xenograft tumor model were undertaken to study the PDCD2’s biological function in glioma(GBMLGG).The PDCD2 gene was associated with solid cancer *** the functional enrichment analysis results,PDCD2 was shown to participate in several important GBMLGG biological *** cells may be inhibited in their proliferation,migration,invasion,and xenograft tumor growth by knocking down *** research can provide new insights into solid cancer prognostic biomarkers of PDCD2.

关键词： Biomarker Glioma Programmed cell death 2 Progression Solid cancer

Typhoon-Induced Ocean Waves and Stokes Drift:A Case Study of Typhoon Mangkhut(2018)

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China Ocean Engineering 2024年第4期38卷 711-724页

作者： WU Zhi-yuan GAO Kai CheN Jie ZHANG hao-jian DENG Bin JIANG Chang-bo LIU Yi-zhuang LYU Zhao YAN Ren School of Hydraulic and Environmental Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China School of Civil Engineering Hunan University of TechnologyZhuzhou 412007China

Ocean waves and Stokes drift are generated by *** study investigated the characteristics of ocean waves and wave-induced Stokes drift and their effects during Typhoon Mangkhut using European Centre for MediumRange Weather Forecasts(ECMWF)ERA5 datasets and observational *** results revealed that the typhoon generated intense cyclones and huge typhoon waves with a maximum wind speed of 45 m/s,a minimum pressure of955 h Pa,and a maximum significant wave height of 12 *** Stokes drift caused by typhoon waves exceeded 0.6m/s,the Stokes depth scale exceeded 18 m,and the maximum Stokes transport reached 6 m^(2)/*** spatial distribution of 10-m wind speed,typhoon wave height,Stokes drift,Stokes depth,and Stokes transport during the typhoon was highly correlated with the typhoon *** distribution along the typhoon track showed significant zonal asymmetry,with greater intensity on the right side of the typhoon track than on the left *** findings provide important insights into the impact of typhoons on ocean waves and Stokes drift,thus improving our understanding of the interactions between typhoons and the ocean *** study also investigated the contribution of Stokes transport to the total net transport during typhoons using Ekman-Stokes Numbers as a comparative *** results indicated that the ratio of Stokes transport to the total net transport reached up to 50%within the typhoon radius,while it was approximately 30%outside the *** Stokes transport induced by typhoon waves led to divergence in the transport direction,which resulted in upwelling of the lower ocean as a compensation ***,Stokes transport played a crucial role in the vertical mixing of the ocean during *** findings suggested that Stokes transport should be paid more attention to,particularly in high latitude ocean regions,where strong winds can amplify its effects.

关键词： Stokes drift typhoon waves Ekman-Stokes transport vertical mixing Typhoon Mangkhut

Interphase migration and enrichment of lead and zinc during copper slag depletion

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Transactions of Nonferrous Metals Society of China 2024年第9期34卷 3029-3041页

作者： Jun hao Zhi-he DOU Xing-yuan WAN Ting-an ZHANG Kun WANG Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Education Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

An interphase migration and enrichment model of lead and zinc during molten copper slag depletion was *** occurrence of various components in copper slag was predicted using sulfur-oxygen potential calculations and confirmed through high-temperature *** recovery rate of copper can reach 90.13%under the optimal conditions of 1200°C,an iron to silicon mass ratio of 1.0,3 wt.%ferrous sulfide,and a duration of 45 ***(54.07 wt.%)and zinc(17.42 wt.%)are found in the flue dust as lead sulfate,lead sulfide,and zinc oxide,while copper matte contains lead(14.44 wt.%)and zinc sulfide(1.29 wt.%).The remaining lead and zinc are encapsulated as oxides within the fayalite phase.

关键词： depletion lead copper slag stirring zinc

Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

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Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao hao Zhao Shuo-Fei Dong Qi Guo Jiao-Jiao Xie Mei-Ling Lv Chun-Gang yuan hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric *** this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample *** compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also *** results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest *** actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward *** was the main exposure pathway for REEs in PM_(2.5)for both children and *** contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and *** exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great *** was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

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