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Chinese Chemical Letters 2024年第2期35卷 558-563页

作者： Sheng Cai Xiao-yuan wu Weiming wu Sa-Sa Wang Can-Zhong Lu CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Xiamen Institute of Rare Earth Materials Chinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Partial substitution of polyoxometalate(POM)is an efficient route to modulate the catalytic property of maternal *** this work,a new Keggin type POM involving{Ni 6}cluster,{[Ni(H_(2)O)_(2)(Dach)_(2)][Ni(Dach)_(2)]_(2)}{[Ni_(6)Cl(μ-OH)_(3)(H_(2)O)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))][Ni_(6)(μ-OH)_(3)(H_(2)O)_(2)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))]}Cl·27H_(2)O,(1,Dach=1,2-diaminocyclohexane)was *** 1 shows excellent catalytic performance in the selective oxidation of aniline to azoxybenzene(AOB)in *** apparently different results from that with the matrix{PW_(9)O_(34)}({PW9})suggest the successful regulation of the catalytic property of{PW9}by the introduction of the{Ni6}cluster into the *** experimental results indicate that the highlighted performance of 1 is contributed by the synergy of W and Ni sites,which are respectively responsible for the oxidation and condensation steps in the production of *** good selectivity to AOB is essentially attributed to the effective modulation of the reaction rates of oxidation and condensation steps by W and Ni sites,respectively.

关键词： Polyoxometalate {Ni_(6)}cluster Modulated catalytic property Aniline oxidation Azoxybenzene

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-qing Li Wen-Hao Wang yuan-Da Su Jun-Xin Guo Xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Effective approaches for enhancing the stability of ruthenium-based electrocatalysts towards acidic oxygen evolution reaction

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Chinese Chemical Letters 2024年第10期35卷 126-138页

作者： Qiyan wu Ruixin Zhou Zhangyi Yao Tanyuan Wang qing Li State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Water splitting with proton exchange membrane water electrolyzers(PEMWE)is regarded as a promising pathway for sustainable hydrogen ***,oxygen evolution reaction(OER)is considered as the dominant factor during the whole process due to the sluggish *** the catalysts,Rubased catalysts draw special attention because of their excellent activity and relatively low ***,the limited stability impedes their further commercialization and tremendous efforts have been devoted to overcome this *** review firstly introduces the basic mechanisms of *** the evaluation protocols and techniques to investigate the stability of Ru-based catalysts are summarized.A detailed elucidation of the possible degradation mechanisms is also critically ***,effective strategies to design durable Ru-based catalysts for acidic OER are *** as heteroatom doping,phase and facet engineering,heterostructure building and support ***,promises,perspectives and challenges in developing highly durable Ru-based catalysts for acidic OER are outlined.

关键词： Acidic oxygen evolution Ru-based catalysts Stability Degradation mechanisms Optimization strategies

Metal/covalent organic frameworks for aqueous rechargeable zinc-ion batteries

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Science China Chemistry 2024年第1期67卷 247-259页

作者： Hu Hong Xun Guo Jiaxiong Zhu Zhuoxi wu qing Li Chunyi Zhi Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

Lithium-ion batteries(LIBs)have become one of the most successful energy storage systems due to their high operating voltage,high energy density,and long cycle ***,with the widespread use of LIBs in recent decades,lithium resources are at risk of being ***,it is necessary to find a substitute for LIBs to meet the needs of future large-scale energy storage *** of their competitiveness,low cost,and high safety,aqueous rechargeable zinc-ion batteries(ARZIBs)are regarded as promising components in the post-lithium-ion-battery *** the tunable composition,ordered porous channels,and controllable structure of metal-organic frameworks(MOFs)and covalent organic frameworks(COFs),these frameworks are viewed as potential materials for developing high-performance *** this review,we focus on the recent developments in the applications of MOF-/COF-based materials in ARZIBs,including in electrode materials,anode modifications,separators,and solid *** then focus on the critical factors and optimization techniques of MOF-/COF-based materials that affect the performance of ***,we conclude with some projections for the expansion of ARZIBs containing MOF-/COF-based materials.

关键词： metal/covalent organic frameworks aqueous zinc-ion batteries electrode materials anode modifications separators electrolytes

Thermal stability of permafrost under U-shaped crushed rock embankment of the qinghai-Tibet Railway

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Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-Ming XU Guan-Li JIANG Ji CHEN qing-Bai wu State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying ***,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling *** study focuses on nine UCRE monitoring sites along the qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to *** efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the *** short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost ***,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the *** results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate *** findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the qinghai-Tibet Railway.

关键词： qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

Yiwei Xiaoyu granules for treatment of chronic atrophic gastritis with deficiency syndrome of the spleen and stomach

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World Journal of Clinical Cases 2024年第13期12卷 2201-2209页

作者： Wan-Qun Chen qing-Feng Fan yuan-Jun He Fei Li Xin wu Yan-Ping Li Xiao-Jun Yang Department of Gastroenterology Chongqing Hospital of Traditional Chinese MedicineChongqing 400000China

BACKGROUND The Correa sequence,initiated by Helicobacter pylori(***),commonly progresses to gastric cancer through the stage of chronic atrophic gastritis(CAG).Although eradication of *** only reduces the risk of gastric cancer,it does not eliminate the risk for neoplastic *** Xiaoyu granules(YWXY)are a commonly used composite preparation in Chinese ***,the pursuit of excellence in clinical trials and the establishment of standardized animal experiments are still needed to contribute to full understanding and application of traditional Chinese medicine in the treatment of *** To demonstrate the effectiveness of YWXY in patients with CAG and spleenstomach deficiency syndrome(DSSS),by alleviating histological scores,improving response rates for pathological lesions,and achieving clinical efficacy in relieving DSSS *** We designed a double-blind,randomized,controlled *** study enrolled seventy-two ***-negative patients(mean age,52.3 years;38 men)who were randomly allocated to either the treatment group or control group in a 1:1 ratio,and treated with 15 g YWXY or 0.36 g Weifuchun(WFC)tablet combined with the respective dummy for 24 *** pre-randomization phase resulted in the exclusion of 72 patients:50 participants did not meet the inclusion criteria,12 participants declined to participate,and 10 participants were excluded for various other *** visits were conducted during the study,and histopathological examination with target endoscopic biopsy of narrow-band imaging was requested before the first and seventh *** also evaluated endoscopic performance scores,total symptom scores,serum pepsinogen and *** Six patients did not complete the trial *** with YWXY improved the Operative Link on Gastric Intestinal Metaplasia Assessment(OLGIM)stage,compared with WFC(P<0.05).YWXY provided better relief from symptoms of DSSS and better improvement in serum gastric fun

关键词： Chronic atrophic gastritis Yiwei Xiaoyu granules Randomized clinical trial Weifuchun tablet Traditional Chinese medicine Helicobacter pylori

A Hand Features Based Fusion Recognition Network with Enhancing Multi-Modal Correlation

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 537-555页

作者： Wei wu yuan Zhang Yunpeng Li Chuanyang Li YanHao School of Information Engineering Shenyang UniversityShenyang110044China

Fusing hand-based features in multi-modal biometric recognition enhances anti-spoofing ***,it leverages inter-modal correlation to enhance recognition ***,the robustness and recognition performance of the system can be enhanced through judiciously leveraging the correlation among multimodal ***,two issues persist in multi-modal feature fusion recognition:Firstly,the enhancement of recognition performance in fusion recognition has not comprehensively considered the inter-modality correlations among distinct ***,during modal fusion,improper weight selection diminishes the salience of crucial modal features,thereby diminishing the overall recognition *** address these two issues,we introduce an enhanced DenseNet multimodal recognition network founded on feature-level *** information from the three modalities is fused akin to RGB,and the input network augments the correlation between modes through channel *** the enhanced DenseNet network,the Efficient Channel Attention Network(ECA-Net)dynamically adjusts the weight of each channel to amplify the salience of crucial information in each modal *** separable convolution markedly reduces the training parameters and further enhances the feature *** evaluations were conducted on four multimodal databases,comprising six unimodal databases,including multispectral palmprint and palm vein databases from the Chinese Academy of *** Equal Error Rates(EER)values were 0.0149%,0.0150%,0.0099%,and 0.0050%,*** comparison to other network methods for palmprint,palm vein,and finger vein fusion recognition,this approach substantially enhances recognition performance,rendering it suitable for high-security environments with practical *** experiments in this article utilized amodest sample database comprising 200 *** subsequent phase involves preparin

关键词： Biometrics multi-modal correlation deep learning feature-level fusion

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu Hong-wu Tang Sai-yu yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells

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Journal of Energy Chemistry 2024年第5期92卷 142-150页

作者： Fengling Zhao Qiang yuan Siyang Nie Liang wu Xun Wang State-Local Joint Laboratory for Comprehensive Utilization of Biomass Center for R&D of Fine ChemicalsCollege of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025GuizhouChina Key Lab of Organic Optoelectronics&Molecular Engineering Tsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet ***,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel *** modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/*** in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct *** functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic *** synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources.

关键词： Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells

Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： Hong HUANG Dan wu yuan WANG Zhen WANG Yu LIU College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method