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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li Jing-Zhi wang Zhi-liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

Optimal Model Average Prediction in Orthogonal Kriging Models

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Journal of Systems Science & Complexity 2024年第3期37卷 1080-1099页

作者： wang Jun HE Jiabei liang Hua LI Xinmin School of Mathematics and Statistics Qingdao UniversityQingdao 266071China Department of Statistics George Washington UniversityWashington DC 20052USA

The main objective of this paper is to consider model averaging methods for kriging *** paper proposes a Mallows model averaging procedure for the orthogonal kriging model and demonstrate the asymptotic optimality of the model averaging estimators in terms of mean square *** studies are conducted to evaluate the performance of the proposed method and compare it with the competitors to demonstrate its *** authors also analyse a real dataset for an illustration.

关键词： Asymptotic optimality Mallows criterion optimal model averaging orthogonal kriging model

Differentially-grown cobalt regulators cooperatively involved in the tandem catalysis for high-yield production of second amines

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Nano Research 2024年第4期17卷 2444-2450页

作者： Jinhui Xu Xiao wang Ying wang fei wang Lingling Zhang Wenjie Cui Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry Tsinghua UniversityBeijing 100084China

One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall *** promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem *** this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance *** comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are ***,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline ***,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring *** from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).

关键词： tandem catalysis CeO_(2) hierarchical structure heterogeneous catalyst dual-site materials

Screening of transition metal oxides for electrocatalytic nitrate reduction to ammonia at large currents

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Nano Research 2024年第5期17卷 3902-3910页

作者： Qiongfei Wu Weijie Zhu Dongxu Ma Chao liang Zhoucheng wang Hanfeng liang State Key Laboratory of Physical Chemistry of Solid Surfaces Tan Kah Kee Innovation LaboratoryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Chemical Engineering Tianjin UniversityTianjin 300072China

Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recently aroused wide concern and ***,the current research of the NO_(3)RR towards ammonia lacks the overall performance comparison of various *** this,we here make a comparison of 12 common transition metal oxide catalysts for the NO_(3)RR under a high cathodic current density of 0.25 A·cm^(-2),wherein Co_(3)O_(4) catalyst displays the highest ammonia Faradaic efficiency(85.15%)and moderate activity(ca.-0.25 V *** hydrogen electrode).Other external factors,such as nitrate concentrations in the electrolyte and applied potential ranges,have also been specifically investigated for the NO_(3)RR.

关键词： nitrate reduction reaction ammonia production transition metal oxides Co_(3)O_(4)

Passive imaging through dense scattering media

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Photonics Research 2024年第1期12卷 134-140页

作者： YAOMING BIAN fei wang YUANZHE wang ZHENFENG FU HAISHAN LIU HAIMING YUAN GUOHAI SITU Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Imaging through non-static and optically thick scattering media such as dense fog,heavy smoke,and turbid water is crucial in various ***,most existing methods rely on either active and coherent light illumination,or image priors,preventing their application in situations where only passive illumination is *** this study we present a universal passive method for imaging through dense scattering media that does not depend on any prior *** the selection of small-angle components out of the incoming information-carrying scattering light and image enhancement algorithm that incorporates timedomain minimum filtering and denoising,we show that the proposed method can dramatically improve the signal-to-interference ratio and contrast of the raw camera image in outfield experiments.

关键词： scattering media illumination

CMAES-WFD:Adversarial Website Fingerprinting Defense Based on Covariance Matrix Adaptation Evolution Strategy

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Computers, Materials & Continua 2024年第5期79卷 2253-2276页

作者： Di wang Yuefei Zhu Jinlong fei Maohua Guo School of Cyberspace Security Information Engineering UniversityZhengzhou450000China

Website fingerprinting,also known asWF,is a traffic analysis attack that enables local eavesdroppers to infer a user’s browsing destination,even when using the Tor anonymity *** advanced attacks based on deep neural network(DNN)can performfeature engineering and attain accuracy rates of over 98%,research has demonstrated thatDNNis vulnerable to adversarial *** a result,many researchers have explored using adversarial samples as a defense mechanism against DNN-based WF attacks and have achieved considerable ***,these methods suffer from high bandwidth overhead or require access to the target model,which is *** paper proposes CMAES-WFD,a black-box WF defense based on adversarial *** process of generating adversarial examples is transformed into a constrained optimization problem solved by utilizing the Covariance Matrix Adaptation Evolution Strategy(CMAES)optimization *** are injected into the local parts of the original traffic to control bandwidth *** to the experiment results,CMAES-WFD was able to significantly decrease the accuracy of Deep Fingerprinting(DF)and VarCnn to below 8.3%and the bandwidth overhead to a maximum of only 14.6%and 20.5%,***,for Automated Website Fingerprinting(AWF)with simple structure,CMAES-WFD reduced the classification accuracy to only 6.7%and the bandwidth overhead to less than 7.4%.Moreover,it was demonstrated that CMAES-WFD was robust against adversarial training to a certain extent.

关键词： Traffic analysis deep neural network adversarial sample Tor website fingerprinting

Bioinspired Additive Manufacturing of Hierarchical Materials: From Biostructures to Functions

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Research 2024年第1期2023卷 533-559页

作者： Jingjiang Wei fei Pan Hang Ping Kun Yang Yanqing wang Qingyuan wang Zhengyi Fu Institute for Advanced Materials Deformation and Damage from Multi-Scale Institute for Advanced StudyChengdu UniversityChengdu 610106P.R.China Department of Chemistry University of BaselBasel 4058Switzerland State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070P.R.China College of Polymer Science and Engineering Sichuan UniversityChengdu 610065P.R.China

Throughout billions of years,biological systems have evolved sophisticated,multiscale hierarchical structures to adapt to changing *** are synthesized under mild conditions through a bottom-up self-assembly process,utilizing substances from the surrounding environment,and meanwhile are regulated by genes and *** manufacturing,which mimics this natural process,provides a promising approach to developing new materials with advantageous properties similar to natural biological *** review presents an overview of natural biomaterials,emphasizing their chemical and structural compositions at various scales,from the nanoscale to the macroscale,and the key mechanisms underlying their ***,this review describes the designs,preparations,and applications of bioinspired multifunctional materials produced through additive manufacturing at different scales,including nano,micro,micro-macro,and macro levels.

关键词： materials structures utilizing

Water Changes and Sources of Siling Co Using Landsat and GRACE Data since 1972

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Journal of Earth Science 2024年第2期35卷 687-699页

作者： Chuya wang Yuande Yang fei Li Junhao wang Leiyu Li Huiting Yu Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan430079China

The inland lakes on the Tibetan Plateau(TP)are undergoing significant changes due to their sensitivity to *** largest lake in Tibet,Siling Co,has expanded most dramatically during recent *** Landsat,GRACE and meteorological data,the expansion of Siling Co was detailed in four stages and the process was further *** results show that the lake area increased from 1647.30 km^(2)in 1972 to 2438.99 km^(2)in *** experienced a slow growth at a rate 6.03 km^(2)/yr from 1972 to 1988,while fluctuating at 1.44 km^(2)/yr during 1989–1997,then accelerated at 60.28 km^(2)/yr between 1998 and 2005,and expanded slowly again at 11.40 km^(2)/yr since *** continued expansion led to its merger with nearby Yagain Co in *** water storage(TWS)increase was also observed from GRACE(0.65 cm/yr),with about 0.75 coefficient of determination between the TWS and lake area during 2002–*** long-term expansion of Siling Co is related to the increasing trends of temperature and precipitation,but their contributions vary with time ***,the accelerated stage between 1998 and 2005 can be explained by the increased temperature and precipitation accompanied by a drop in evaporation,while the slow expansion since 2006 was due to the decrease in precipitation and temperature and the rise in *** is no obvious mass loss of glaciers revealed by GRACE during 2002–2020,which may be related to the negative trend of the ***,the precipitation may still make a major contribution in this phase,as its average is about 93.9 mm higher than that in 1988–1997.

关键词： lake area remote sensing climate change Siling Co Tibetan Plateau environmental geology

Highly active and durable core-shell electrocatalysts for proton exchange membrane fuel cells

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Nano Research 2024年第10期17卷 8772-8784页

作者： Hsiwen Wu fei Xiao Jing wang Meng Gu Minhua Shao Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Fok Ying Tung Research Institute The Hong Kong University of Science and TechnologyGuangzhou 511458China Energy Institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

This work presents simple post-treatment methods to selectively and partially remove the Pd core of Pd-Pt core–shell(Pt@Pd/C)*** proton exchange membrane fuel cell with the post-treated Pt@Pd/C cathode(Pt loading:0.10 mg·cm^(-2))delivers an impressive peak power density of 1.2 W·cm^(-2).The partial removal of Pd core endows an ultrahigh oxygen reduction reaction(ORR)mass activity of 0.32 A·g_(PGM)-1 when normalized to the platinum group metal(PGM)mass,or equivalently 0.55 A·mg_(Pt)^(-1) at 0.9 V measured in a fuel *** post-treatment thickens the Pt shells and mitigates the Pd dissolution during potential *** a result,the post-treated core-shell catalyst demonstrates superior durability in ORR mass activity and polarization power density retention than untreated core-shell catalyst and benchmark Pt/***-situ inductively coupled plasmamass spectrometry(ICP-MS)results highlight that the amount of dissolved Pd in post-treated core–shell catalyst is 17-times lower than that of the untreated *** findings highlight the importance of structural tuning of catalysts in enhancing their mass activity and durability.

关键词： core-shell catalyst platinum monolayer proton exchange membrane fuel cell oxygen reduction reaction durability

The changes in soil organic carbon stock and quality across a subalpine forest successional series

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Forest Ecosystems 2024年第4期11卷 423-433页

作者： fei Li Zhihui wang Jianfeng Hou Xuqing Li Dan wang Wanqin Yang Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation School of Life SciencesTaizhou UniversityTaizhou 318000China Linhai Station of Zhejiang Provincial Forest Ecological Research Taizhou UniversityTaizhou 318000China Taizhou Key Laboratory of Mountain Ecological Restoration and Special Industry Cultivation Taizhou UniversityTaizhou 318000China Hawkesbury Institute for the Environment Western Sydney UniversityPenrithNew South WalesAustralia

Soil organic carbon(SOC)affects the function of terrestrial ecosystem and plays a vital role in global carbon ***,large uncertainty still existed regarding the changes in SOC stock and quality with forest ***,the stock and quality of SOC at 1-m soil profile were investigated across a subalpine forest series,including shrub,deciduous broad-leaved forest,broadleaf-conifer mixed forest,middle-age coniferous forest and mature coniferous forest,which located at southeast of Tibetan *** results showed that SOC stock ranged from 9.8 to29.9 kg·m^(-2),and exhibited a hump-shaped response pattern across the forest successional *** highest and lowest SOC stock was observed in the mixed forest and shrub forest,*** SOC stock had no significant relationships with soil temperature and litter stock,but was positively correlated with wood debris ***,the average percentages of polysaccharides,lignins,aromatics and aliphatics based on FTIR spectroscopy were 79.89%,0.94%,18.87%and 0.29%,***,the percentage of polysaccharides exhibited an increasing pattern across the forest successional series except for the sudden decreasing in the mixed forest,while the proportions of lignins,aromatics and aliphatics exhibited a decreasing pattern across the forest successional series except for the sudden increasing in the mixed ***,the humification indices(HIs)were highest in the mixed forest compared to the other four successional stages,which means that the SOC quality in mixed forest was worse than other successional *** addition,the SOC stock,recalcitrant fractions and HIs decreased with increasing soil depth,while the polysaccharides exhibited an increasing *** findings demonstrate that the mixed forest had higher SOC stock and worse SOC quality than other successional *** high proportion of SOC stock(66%at depth of 20-100 cm)and better SOC quality(lower HIs)indicate that deep s

关键词： Forest successional series Soil organic cubon stock Molecular composition Humification indices Soil organic carbon quality