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Friction 2024年第9期12卷 2033-2051页

作者： Qipeng HUANG chaohua wu Xiaoliang SHI Kaipeng ZHANG School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China

Wind power gears will be excessively worn due to lubrication failure during ***,the tribological properties of rubbing pairs are improved by filling solid lubricants into surface *** texture design,three types of topological textures(Circle(C),Hexagon(H),and Circle/Hexagon(ch))were obtained by cell topology optimization,and then three cases with 20%,30%,and 40%density were designed for each ***,SnAgCu and TiC were deposited in texture of AISI 4140 steel(AS)to obtain 9 kinds of self-lubricating *** them,AS with 30%ch density(AS-ch30)exhibits excellent mechanical and tribological *** with AS-C and AS-H,the maximum equivalent stress of AS-ch was decreased by 10.86%and 5.37%,*** coefficient and wear rate of AS-ch30 were 79.68%and 78%lower than those of *** excellent tribological performances of AS-ch30 can be attributed to the synergistic effect of topological surface and solid *** surface can not only reduce fluctuation of equivalent stress,but also promote the stored lubricants to be easily transferred at the contact interface to form a 200 nm lubricating film containing solid lubricants(mainly),oxides and wear debris.

关键词： topological texture nano-TiC self-lubricating solid lubrication

Copper(I)Cluster of Aggregation-Induced Emission and X-Ray Scintillator characteristic

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chemical Research in chinese Universities 2024年第5期40卷 887-893页

作者： XIONG Jiayu wu Minjian YAO Liao-Yuan MOE Key Laboratory of Cluster Sciences Beijing Key Laboratory of Photoelectroic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing102488P.R.China Tangshan Research Institute Beijing Institute of TechnologyTangshan063000P.R.China

Due to their precise atomic structures,photoluminescent copper nanoclusters(Cu NCs)have promising applications in basic research and technical applications,such as bioimaging,cell labeling,phototherapy,and photoactivation *** this work,we report a simple strategy for synthesizing novel CuNCs co-protected by alkynyl and phosphine ligands with the molecular formula[Cu_(7)(PPh_(3))_(10)(PE)_(3)(ch_(3)O)](Cu_(4)@Cu_(3)).Single-crystal X-ray crystallography reveals that the NC core exhibits an open square structure and an overall pyramid *** Cu_(4)@Cu_(3) units are connected through weak interactions to form dimers in crystals,creating a molecular cage that looks like two tightly closed ***_(4)@Cu_(3)exhibits dual emission in the visible *** is also an aggregation-induced emission(AIE)-active luminescent substance,which exhibits strong emission in the visible light region when ***,it has the properties of radioluminescent(RL)and could be a potential scintillator *** study not only enriches the types of atomically accurate AIE clusters,but also holds significant importance for the development of a new generation of high-performance and environmentally friendly X-ray scintillators.

关键词： Copper nanocluster Aggregation-induced emission X-Ray scintillator

Boosting oxygen vacancies by modulating the morphology of Au decorated In_(2)O_(3)with enhanced CO_(2)hydrogenation activity to ch_(3)OH

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Journal of Environmental Sciences 2024年第6期140卷 91-102页

作者： Ruxian Hou Jiewen Xiao Qian wu Tianyu Zhang Qiang Wang Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

CO_(2)hydrogenation to methanol has become one of the most promising ways for CO_(2)utilization,however,the CO_(2)conversion rate and methanol selectivity of this reaction still need to be improved for industrial *** we investigated the structure-activity relationship for CO_(2)conversion to methanol of In_(2)O_(3)-based catalysts by modulating morphology and decorating *** different Au/In_(2)O_(3)catalysts were prepared,their activity follow the sequence of Au/In_(2)O_(3)-nanosphere(Au/In_(2)O_(3)-NS)>Au/In_(2)O_(3)-nanoplate(Au/In_(2)O_(3)-NP)>Au/In_(2)O_(3)-hollow microsphere(Au/In_(2)O_(3)-HM).Au/In_(2)O_(3)-NS exhibited the best performance with good CO_(2)conversion of 12.7%,high methanol selectivity of 59.8%,and large space time yield of 0.32 g ch_(3)OH/(hr·gcat)at 300℃.The high performance of Au/In_(2)O_(3)-NS was considered as the presence of *** contributes to the creation of more surface oxygen vacancies,which further promoted the CO_(2)adsorption and facilitated CO_(2)activation to form the formate intermediates towards *** work clearly suggests that the activity of In_(2)O_(3)catalyst can be effective enhanced by structure engineering and Au decorating.

关键词： CO_(2)hydrogenation Methanol Au/In_(2)O_(3) Morphology Oxygen vacancies

Structural Stability of Natural Magnesiochromite at High-Temperature-Pressure Conditions

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Journal of Earth Science 2024年第4期35卷 1196-1203页

作者： Shuyu Jin Xiang wu Yungui Liu Yanfei Zhang chao Wang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan430074China College of Gems and Materials Hebei GEO UniversityShijiazhuang050031China

The podiform chromitites in the Luobusha ophiolite have been thought to experience a very deep formation,but the maximum depth is still an open ***,we have investigated the structural stability of natural magnesiochromite using the synchrotron-based powder X-ray diffraction and diamond anvil cells up to 48.6 GPa and 2450 *** results have shown that spinel-type magnesiochromite first decomposes into corundum-type‘Cr_(2)O_(3)’+B1-type‘MgO’at 11–14 GPa and 1250–1450 K,then modified ludwigite(mLd)-type‘Mg_(2)Cr_(2)O_(5)’+corundum-type‘Cr_(2)O_(3)’at 14.3–20.5 GPa and 1300–2000 K,and finally CaTi_(2)O_(4)-type phase at 24.5 *** the quenching procession from high-temperature-pressure conditions,the mLd-type phase appeared again and was kept at ambient *** also obtained the isothermal equation states of spinel-type and CaTi_(2)O_(4)-type phases,revealing the composition effect on their *** on the updated results,we propose chromitites could not experience pressure exceeding∼14.3 GPa(approximate maximum depth∼400 km)in the subduction-recycling genesis model.

关键词： chromite high-temperature and high-pressure phase transitions equation of state chromitites genesis

Laminar Flame Structure-Dependent Exergy Destruction Behavior at Auto-Ignition Time Scale:A Case Study of Dimethyl Ether(DME)

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Journal of Thermal Science 2024年第4期33卷 1257-1271页

作者： wu Honghuan HUANG Wenlin ZHAO Hao SUN wuchuan HUANG Zuohua ZHANG Yingjia State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China

Hybrid deflagration/auto-ignition flame structures coexist in the combustion of advanced *** exergy destruction caused by different irreversible processes under varied flame regimes is thus important for understanding engine *** this study,the flame propagation modes for the premixed DME/air mixtures are numerically investigated under engine-relevant *** entropy generation and exergy destruction characteristics are compared under different flame *** reveal that as the typical premixed flame transition towards auto-ignition front,the exergy destruction from heat conduction and species mass diffusion gradually vanish and are dominated by chemical *** distributions of temperature and species mole fraction in the flame domain are analyzed to clarify the exergy destruction behaviors caused by heat conduction and mass ***,by dividing the DME oxidation process into four stages,the main reaction channels that contribute to the increase in exergy destruction from chemical reaction have been *** is found that the production and consumption of ch_(2)O and HO_(2) radical dominate the exergy destruction behavior during DME *** this basis,the kinetic mechanism of low-temperature chemistry causing greater exergy destruction is ***,low-temperature chemistry leads to significant exergy destruction due to(a)the large irreversibility of itself and(b)(mainly)the enhancement of H_(2)O_(2)loop reactions by low-temperature reaction *** the reduction of combustion irreversibility is promising to be achieved by reasonably regulating the fuel oxidation path.

关键词： exergy destruction flame structures entropy generation low-temperature chemistry DME

OH regulator of highly dispersed Ru sites on host Pd nanocrystals for selective ethanol electro-oxidation

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Nano Research 2024年第5期17卷 3863-3871页

作者： Zhihe Xiao Yueguang chen Renjie wu Yuwei He chunfeng Shi Leyu Wang State Key Laboratory of chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Research Institute of Petroleum Processing SINOPECBeijing 100083China

The ethanol oxidation reaction(EOR)is crucial in direct alcohol fuel cells and chemical ***,the electro-oxidation of ethanol molecules to produce acetaldehyde and carbon monoxide can poison the active sites of nanocatalysts,resulting in reduced performance and posing challenges in achieving high activity and selectivity for ethanol *** this study,we employed a dynamic seed-mediated method to precisely modify highly dispersed Ru sites onto well-defined Pd *** oxyphilic Ru sites serve as"OH valves",regulating water dissociation,while the surrounding Pd atomic arrangements control electronic states for the oxidation dehydrogenation of carbonaceous ***,Ru0.040@Pd nanocubes(Ru:Pd=0.04 at.%),featuring(100)facets in Ru-Pd4 configurations,demonstrate an outstanding mass activity of 6.53 A·mgPd^(-1) in EOR under alkaline conditions,which is 6.05 times higher than that of the commercial Pd/C catalyst(1.08 A·mgPd-1).Through in-situ experiments and theoretical investigations,we elucidate that the hydrophilic Ru atoms significantly promote the dynamic evolution of H_(2)O dissociation into OHads species,while the electron redistribution from Ru to adjacent Pd concurrently adjusts the selective oxidation of C_(2) *** host-guest interaction accelerates the subsequent oxidation of carbonaceous intermediates(ch_(3)CO_(ads))to acetate,while preventing the formation of toxic*chx and*CO species,which constitutes the rate-determining step.

关键词： OH regulator atomic sites ethanol electro-oxidation host-guest interaction

Photochemical Production of Methyl Halides with Guaiacol as the Precursor

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Journal of Ocean University of china 2024年第5期23卷 1275-1286页

作者： YANG Fan ZHANG Yan wu Guanyu HE Zhen YANG Guipeng Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao Marine Science and Technology CenterQingdao 266237China Institute of Marine chemistry Ocean University of ChinaQingdao 266100China

Methyl halides are crucial trace greenhouse gases in the atmosphere,playing a significant role in global climate change and the atmospheric *** study investigated the photochemical production of methyl halides in an artificial seawater system using guaiacol as a precursor through laboratory simulation *** influences of various environmental factors,including illumination time,radiation wavebands,illumination intensity,concentrations of guaiacol and halide ions(X^(-)),Fe^(3+),salinity,dissolved oxygen(DO),and pH value on the photochemical production of methyl halides were *** demonstrated that increased illumination intensity and duration promote the photochemical production of methyl halides,with a notable enhancement under UV-B *** and halide ions were identified as key precursors,and their high concentrations facilitated the formation of methyl ***,different types of halide ions exhibited a competitive relationship in producing methyl *** study found that an increase in pH inhibited the photochemical formation of ch_(3)I due to the reaction between OH^(-)and·ch_(3).Dissolved oxygen was found to inhibit the photochemical formation of ch3I while promoting the formation of ch_(3)***,an appropriate concentration of Fe^(3+)enhanced the photochemical production of methyl *** observations indicated a high photochemical production of methyl halides in the natural waters near Qingdao’s coastal area,likely due to the high concentration of dissolved organic matter(DOM),which supports photochemical ***,the photochemical production of methyl halides in natural seawater was significantly higher than in dark conditions,underscoring the importance of illumination in promoting these photochemical processes in seawater.

关键词： methyl halides photochemical production dissolved organic matter guaiacol

High adsorption selectivity of activated carbon and carbon molecular sieve boosting CO_(2)/N_(2) and ch_(4)/N_(2) separation

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chinese Journal of chemical Engineering 2024年第3期67卷 282-297页

作者： Siang chen Wenling wu Zhaoyang Niu Deqi Kong Wenbin Li Zhongli Tang Donghui Zhang The Research Center of chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Flue gas and coal bed methane are two important sources of greenhouse *** swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is *** this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and ch_(4) from coal bed methane,adsorption isotherms of CO_(2),ch_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 *** experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric *** the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>ch_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-ch_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>ch_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular ***,the adsorption selectivity of ch_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and ch_(4) *** study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.

关键词： Activated carbon Carbon molecular sieve Adsorbent evaluation Adsorption equilibrium and kinetics Heat of adsorption Selectivity

High-sensitivity intelligent packaging films harnessing rose anthocyanins and hydrophilic silica aerogel for visual food freshness monitoring

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Food Quality and Safety 2024年第1期8卷 179-189页

作者： Wenjun wu Luman Zheng Jiahao Yu Liming Liu Gulden Goksen Ping Shao Department of Food Science and Technology Zhejiang University of TechnologyZhejiangHangzhouChina Department of Food Technology Vocational School of Technical Sciences at Mersin Tarsus Organized Industrial ZoneTarsus UniversityMersinTurkey Eco-Industrial Innovation Institute ZJUT Zhejiang University of TechnologyZhejiangQuzhouChina

The enhancement of the sensitivity for anthocyanin-based indicator films in food freshness monitoring in real time is important for *** this study,hydrophilic silica aerogel(SiO2 NA)was incorporated into corn starch(CS)/chitosan(ch)/rose anthocyanins(RACNs)-encapsulated potato amylopectin nanoparticles(APNPs)composite film to increase the sensitivity for shrimp freshness *** microstructure of films revealed that the gas absorption capacity was improved by amorphous SiO2 NA via hydrogen *** pore size(1.74–5.60 times),pore volume(3.92–5.60 times),and specific surface area(2.21–2.34 times)of films increased with the addition of SiO2 *** sensing of NH3 and pH and the reversibility of films were also ***,the pH-responsive films containing SiO2 NA changed visibly in color from purple–red to orange–gray and finally to gray,enabling effective monitoring of shrimp freshness during storage at 4°***,anthocyanin-based indicator films with improved sensitivity by adding SiO2 NA were successfully designed for monitoring shrimp freshness.

关键词： Hydrophilic silica aerogel anthocyanins sensitivity pH-responsive shrimp freshness intelligent packaging

Lean methane combustion over zeolite-supported Pd catalysts:Structure-performance relationship and deactivation mechanism

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Journal of Environmental Sciences 2024年第11期145卷 128-138页

作者： Xingyu Liu Jingkun chen Bowen Han Renna Li Le Shi Zhongbiao wu Xiaole Weng Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Zeolites are a promising support for Pd catalysts in leanmethane(ch_(4))***,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in ch_(4)*** show that variations in zeolite structure and surface acidity led to distinct changes in Pd ***/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for ch_(4)***/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and ***,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the ch_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.

关键词： Methane combustion Pd catalysts Zeolite Structure-performance relationship Deactivation mechanism