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Environmental Conditions Conducive to the Formation of Multiple Tropical Cyclones over the Western North Pacific

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Advances in Atmospheric Sciences 2024年第10期41卷 2027-2042页

作者： Yining GU Ruifen zhan Xiaomeng li Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan University CMA-FDU Joint Laboratory of Marine Meteorology Institute of Desert and Meteorology China Meteorological Administration

There is limited understanding regarding the formation of multiple tropical cyclones(MTCs). This study explores the environmental conditions conducive to MTC formation by objectively determining the atmospheric circulation patterns favorable for MTC formation over the western North Pacific. Based on 199 MTC events occurring from June to October 1980–2020, four distinct circulation patterns are identified: the monsoon trough(MT) pattern, accounting for 40.3% of occurrences, the confluence zone(CON) pattern at 26.2%, the easterly wave(EW) pattern at 17.8%, and the monsoon gyre(MG) pattern at 15.7%. The MT pattern mainly arises from the interaction between the subtropical high and the monsoon trough, with MTCs forming along the monsoon trough and its flanks. The CON pattern is affected by the subtropical high,the South Asian high, and the monsoon trough, with MTCs emerging at the confluence zone where the prevailing southwesterly and southeasterly flows converge. The EW pattern is dominated by easterly flows, with MTCs developing along the easterly wave train. MTCs in the MG pattern arise within a monsoon vortex characterized by strong southwesterly flows. A quantitative analysis further indicates that MTC formation in the MT pattern is primarily governed by mid-level vertical velocity and low-level vorticity, while mid-level humidity and vertical velocity are significantly important in the other patterns. The meridional shear and convergence of zonal winds are essential in converting barotropic energy from the basic flows to disturbance kinetic energy, acting as the primary source for eddy kinetic energy growth.

关键词： barotropic energy conversion circulation pattern monsoon trough multiple tropical cyclones western North Pacific

Context‑dependent antioxidant defense system(ADS)‑based stress memory in response to recurrent environmental challenges in congeneric invasive species

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Marine life Science & Technology 2024年第2期6卷 315-330页

作者： Hanxi li Xuena Huang Aibin zhan Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine *** withstand recurring environmental challenges,marine organisms,especially benthic species lacking behavioral choices to select optimal habitats,have to utilize well-established strategies such as the antioxidant defense system(ADS)to ensure their ***,understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental *** we conducted a com-parative analysis of the physiological and transcriptional responses based on the ADS during two rounds of'hypersalinity-recovery'challenges in two model congeneric invasive ascidians,Ciona robusta and *** results demonstrated that *** exhibited higher tolerance and resistance to salinity stresses at the physiological level,while *** demonstrated heightened responses at the transcriptional *** observed distinct transcriptional responses,particularly in the utilization of two superoxide dismutase(SOD)*** Ciona species developed physiological stress memory with elevated total SOD(T-SOD)and glutathione(GSH)responses,while only *** demonstrated transcriptional stress *** regulatory distinctions within the Nrf2-Keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona *** findings support the'context-dependent stress memory hypothesis',emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental *** results enhance our understanding of the mechanisms of environmental challenge manage-ment in marine species,particularly those related to the ADS.

关键词： Antioxidant defense Ascidian Biological invasion Environmental stress Stress memory

Surface Elastic Effects on Electromechanical Responses of a Piezoelectric Semiconducting Nanobeam

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Acta Mechanica Solida Sinica 2024年第4期37卷 598-612页

作者： Aowen Bao Xiaobao li Yuxue Pu Chunxiao zhan School of Civil Engineering Hefei University of TechnologyHefei230009China

Piezoelectric semiconductors(PSCs)find extensive applications in modern smart electronic devices because of their dual properties of being piezoelectric and *** the increasing demand for miniaturization of these devices,the performance of their components needs to be carefully designed and optimized,especially when reduced to *** has been shown that surface elastic properties play a substantial role in the mechanical performance of nanoscale materials and *** on this understanding,the surface elastic effects,encompassing surface residual stress,surface membrane stiffness,and surface bending stiffness,are comprehensively taken into account to explore the electromechanical responses of a PSC ***,the flexoelectric effect on their responses is also systematically *** results of this work reveal that surface elastic properties predominantly influence mechanical performance,while the flexoelectric effect plays a more dominant role in electric-related quantities at the ***,the significance of surface bending rigidity,which was often underestimated in the earlier literature,is ***,owing to the flexoelectric effect,the linear distribution of electric potential and charge carriers along the length transforms into a nonlinear *** distributions of electric potential and charge carriers across the cross section are also evidently ***,the size-dependent responses are *** findings may provide valuable insights for optimizing electronic devices based on nanoscale PSCs.

关键词： Surface elastic effect Flexoelectricity Size effect Piezoelectric semiconductor

Facile formation of hierarchical magnesium silicate hydrate microspheres as an adsorbent for the textile dyes

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Particuology 2024年第10期93卷 99-110页

作者： tin Kyawoo Naveed Karim Chao Jiang Saeed Ahmed Weiliang Tian Huiyu li Yongjun Feng State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsBeijing University of Chemical TechnologyBeijing100029China Department of Chemistry The University of ChakwalChakwal48800Pakistan College of Chemistry and Chemical Engineering Tarim UniversityAlar843300China

Hierarchical porous magnesium silicate hydrate (MSH) microspheres composed of sheets are successfully developed under facile conditions using a hard template. The role of hexadecyltrimethylammonium bromide (CTAB) on the formation and adsorption behavior was also observed for the methyl orange and methylene blue. The formed MSH possesses a surface area of 453.24 m^(2)/g, an average pore size of 6.38 nm, and a pore volume of 0.75 cm^(3)/g without CTAB. Based on the role of CTAB and the change in the ratio of Mg/Si, the MSH retained its sphere-like structure with a variation in pore parameters. The formed MSH was used as an adsorbent to remove methylene blue and methyl orange. The pseudo-second-order kinetic and Langmuir Isotherm models are well-fitted, with a 256.4 mg/g removal capacity and 84.2 mg/g for methylene blue and methyl orange, respectively. The modified MSH with CTAB played a positive role for the methyl orange and a negative role for the methylene blue regarding removal performance.

关键词： Adsorption Hierarchical microspheres Magnesium silicate Methyl orange Methylene blue Surfacemodification

Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence Technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan liu Chunyuan liu Yifei Hao Yi zhang li Chen zhan li Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China Institute of Defense Engineering AMSPLABeijing 100850China Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab

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Bond behavior of the interface between concrete and basalt fiber reinforced polymer bar after freeze–thaw cycles

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 630-641页

作者： li HONG Mingming li Congming DU Shenjiang HUANG Binggen zhan Qijun YU Department of Structural Engineering Hefei University of TechnologyHefei 230009China Key Laboratory of Performance Evolution and Control for Engineering Structures Tongji UniversityShanghai 200092China Engineering Research Center of Low-carbon Technology and Equipment for Cement-based Materials(Ministry of Education) Hefei University of TechnologyHefei 230009China Hefei Cement Research&Design Institute Corporation Ltd. Hefei 230051China

The shear bond of interface between concrete and basalt fiber reinforced polymer(BFRP)bars during freeze–thaw(F–T)cycles is crucial for the application of BFRP bar-reinforced concrete structures in cold *** this study,48 groups of pull-out specimens were designed to test the shear bond of the BFRP-concrete interface subjected to F–T *** effects of concrete strength,diameter,and embedment length of BFRP rebar were investigated under numerous F–T *** results showed that a larger diameter or longer embedment length of BFRP rebar resulted in lower interfacial shear bond behavior,such as interfacial bond strength,initial stiffness,and energy absorption,after the interface goes through F–T ***,higher concrete strength and fewer F–T cycles were beneficial for enhancing the interfacial bond ***,a three-dimensional(3D)interfacial model based on the finite element method was developed,and the interfacial bond behavior of the specimens was analyzed ***,a degradation bond strength subjected to F–T cycles was predicted by a proposed mechanical *** predictions were fully consistent with the tested *** model demonstrated accuracy in describing the shear bond behavior of the interface under numerous F–T cycles.

关键词： F-T cycle interface shear bond strength bond stress−slip curves bond degradation

Pre-reduction of WO_(3)-Co_(3)O_(4)by H_(2)-C_(2)H_4 in a fluidized bed

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Chinese Journal of Chemical Engineering 2024年第2期66卷 273-284页

作者： Huijun Shang Hengli li Weijun li Feng Pan zhan Du State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences(CAS)Beijing 100190China College of Chemical Engineering Nanjing Technology UniversityNanjing 211816China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832003China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Chinalco Environmental Protection and Energy Conservation Group Co. Ltd.Xiong’an 071700China

In order to avoid the formation ofηphase(W_(6)Co_(6)C or W_(3)Co_(3)C)that adversely affects the sintering process and its products in the preparation process of ultra-fine WC-Co powder,a technical route of prereduction of WO_(3)-Co_(3)O_(4)to WO_(2)-Co and then deep reduction carbonization to WC-Co powder has been *** study mainly investigates the influence of gas partial pressure on the pre-reduction process of WO_(3)-Co_(3)O_(4)under a mixed atmosphere of H_(2)-C_(2)H_(4)-Ar at 600℃and establishes the kinetic equations of pre-reduction and carbon *** results indicate that increasing the partial pressure of hydrogen is conducive to the rapid and complete conversion of WO_(3) to WO_(2).High carbon content can be generated by the deposition of C_(2)H_(4),and it hinders the diffusion of the reducing gas;WO_(3)still cannot be completely reduced to WO_(2)as the partial pressure of C_(2)H_(4) increases to 60%.For the carbon evolution of C_(2)H_(4),the carbon amount is positively related to the H_(2)partial pressure,but it shows the highest amount and evolution rate when the ethylene partial pressure is 20%.Based on the reduction rate curves of WO_(3) and carbon evolution rate curves of C_(2)H_(4),the rate equations of pre-reduction and carbon evolution of WO_(3)-Co_(3)O_(4)system at 600℃are *** pre-reduction reaction belongs to the first-order reaction,and its equation is expressed as follows:r=-(dw_(WO_(3)))/dt=(9±0.15)×10^(-2)×P_(H_(2))^(0.44)P_(C_(2)H_(4))&(0.57)The carbon deposition rate equation of C_(2)H_(4) can be expressed as follows:r=-(dc_C)/dt=r_f-r_b≌7.35×10^(-2)×P_(C_(2)H_(4))^(0.31)

关键词： Fluidization WO_(3)-Co_(3)O_(4) Reduction Carbon deposition Rate equation

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Dimensional reduction enhances photocatalytic carbon dioxide reduction performance of metal-organic frameworks

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Nano Research 2024年第5期17卷 3653-3659页

作者： Kaiyue Ma Jixin li Jinlu liu Chunguang li zhan Shi Shouhua Feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)have shown significant potential as *** has been widely assumed that all catalytic active sites within MOFs are functional in photocatalytic reactions but for a three-dimensional MOF,whether the internal catalytic active sites can effectively absorb light and actively contribute to photocatalytic reactions remains to be *** this context,we synthesized a two-dimensional nanosheet MOF(2D-MOF)and a three-dimensional bulk MOF(3D-MOF)composed of Zr^(6) clusters and tetracarboxylic porphyrin(TCPP)by the approach described in the ***(bpy)(CO)^(3)Cl(bpy=2,2’-bipyridine),which has remarkable CO_(2) photoreduction ability,was introduced to the two MOFs to create two new photocatalysts 2D-MOF-Re and 3D-MOF-Re,*** CO_(2) reduction experiments show that based on the equal number of catalytic active sites,the CO turnover number(TON)of 2D-MOF-Re reaches 27.8 in 6 h,which is 50 times that of *** result shows that certain catalytic active sites inside the bulk MOF are inactive due to the inability to absorb *** study illuminates the potential of the dimensional reduction approach in the design of photocatalysts to exploit the capabilities fully.

关键词： photocatalysis CO_(2)reduction metal-organic frameworks(MOFs) nanosheets light absorption

Single-atom Zn confined in hierarchical hollow microstructure as an acid/base-resistant microwave absorption materials

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Nano Research 2024年第8期17卷 6785-6794页

作者： Yue Lou Jiao li Xiaokun li Zhenyu Zhu zhan Shi Biao Xu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China

Developing acid/base-resistant and low-price microwave-absorbing materials with lighter weight is highly desired for practical applications in extreme ***,we demonstrate the successful synthesis of the N-doped porous carbon(NC)material with hierarchical pore structure by the spray pyrolysis *** large specific surface area(SBET=707.53 m^(2)·g^(−1))of materials enables multiple scattering of incident electromagnetic waves,and N doping greatly enhances the electrical conductivity of the ***,single-atom Zn can adjust the local electronic structure of adjacent sites such as carbon and nitrogen atoms,induce the center of polarization,and thus change the dielectric and electronic properties of the host *** porous carbon coating of single-atom Zn avoids the deterioration of electromagnetic parameters caused by the accumulation of magnetic particles under high-temperature *** the same time,they can also be used in various complex environments,such as acidic and basic ***,NC-1000,with high surface area,low density,and good chemical stability,obtained a minimum reflection loss(RLmin)of−50.5 dB and an effective absorption bandwidth(EAB)exceeding 5.1 GHz at the thickness of 1.9 *** soaking in the strong acid and base solution,the electromagnetic wave absorption performance of the material decreased by<15%.Widely available raw materials and a simple preparation scheme are expected to expedite industrial mass production for this novel type of materials.

关键词： hierarchical hollow microstructure microwave absorption metal-organic framework(MOF) impedance matching singleatom Zn acid/base-resistant