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Boron-doped carbon dots:Doping strategies,performance effects,and applications

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Chinese Chemical Letters 2024年第7期35卷 100-106页

作者： qiang Fu Shouhong Sun Kangzhi Lu Ning li Zhanhua Dong College of Engineering Qufu Normal UniversityRizhao 276826China

Due to their superior fluorescence,phosphorescence,and catalytic capabilities,carbon dots(CDs),an emerging class of fluorescent carbon nanomaterials,have a wide range of potential *** properties of CDs have recently been controlled extensively by heteroatom *** atoms have been effectively doped into the structure of CDs due to their similar size to carbon atoms and excellent electron-absorbing ability to further improve the performance of *** this review,we summarize the research progress of boron-doped CDs in recent years from the aspects of doping strategies,effects of boron doping on different performances of CDs and *** from the two aspects of single boron doping and boron and other atom co-doping,from different precursor materials to different synthesis methods,the doping strategies of boron-doped CDs are reviewed in ***,the effects of boron doping on the fluorescence,phosphorescence and catalytic performance of CDs and applications of boron-doped CDs in optical sensors,information encryption and anti-counterfeiting are ***,we further provide a prospect towards the future development of boron-doped CDs.

关键词： Carbon dots Boron-doped Luminescent material Doping strategies Performance effects

Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research International 2024年第3期31卷 710-718页

作者： Yan-hui Hou Ze-kun Xu Shi-long Zhou Guang-qiang li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

Predicting carbon storage of mixed broadleaf forests based on the finite mixture model incorporating stand factors,site quality,and aridity index

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Forest Ecosystems 2024年第3期11卷 276-286页

作者： Yanlin Wang Dongzhi Wang Dongyan Zhang qiang liu Yongning li College of Forestry Hebei Agricultural UniversityBaoding071001China College of Economics and Management Hebei Agricultural UniversityBaoding071001China

The diameter distribution function(DDF)is a crucial tool for accurately predicting stand carbon storage(CS).The current key issue,however,is how to construct a high-precision DDF based on stand factors,site quality,and aridity index to predict stand CS in multi-species mixed forests with complex *** study used data from70 survey plots for mixed broadleaf Populus davidiana and Betula platyphylla forests in the Mulan Rangeland State Forest,Hebei Province,China,to construct the DDF based on maximum likelihood estimation and finite mixture model(FMM).Ordinary least squares(OLS),linear seemingly unrelated regression(LSUR),and back propagation neural network(BPNN)were used to investigate the influences of stand factors,site quality,and aridity index on the shape and scale parameters of DDF and predicted stand CS of mixed broadleaf *** results showed that FMM accurately described the stand-level diameter distribution of the mixed *** and *** forests;whereas the Weibull function constructed by MLE was more accurate in describing species-level diameter *** combined variable of quadratic mean diameter(Dq),stand basal area(BA),and site quality improved the accuracy of the shape parameter models of FMM;the combined variable of Dq,BA,and De Martonne aridity index improved the accuracy of the scale parameter *** to OLS and LSUR,the BPNN had higher accuracy in the re-parameterization process of ***,LSUR,and BPNN overestimated the CS of *** but underestimated the CS of *** in the large diameter classes(DBH≥18 cm).BPNN accurately estimated stand-and species-level CS,but it was more suitable for estimating stand-level CS compared to species-level CS,thereby providing a scientific basis for the optimization of stand structure and assessment of carbon sequestration capacity in mixed broadleaf forests.

关键词： Weibull function Finite mixture model linear seemingly unrelated regression Back propagation neural network Carbon storage

Crack mechanism of ground fissures in loess layer of Fenwei Basin, China

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Journal of Mountain Science 2024年第5期21卷 1683-1696页

作者： li Cong LU Quanzhong WANG Feiyong LUO Wenchao XU qiang School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of EducationXi’an 710054China Observation and Research Station of Ground Fissure and Land Subsidence Ministry of Natural ResourcesXi’an 710054China School of Engineering and Technology China University of GeosciencesBeijing 100083China

The Fenwei Basin, covered by loess, experiences severe ground fissure disasters. These disasters disrupt the continuity of the loess and pose significant threats to engineering construction safety along transportation routes. Nevertheless, the crack characteristics and the influence zone of ground fissures in the loess layer remain inadequately investigated. To effectively prevent and control ground fissure disasters, physical model tests and the PFC(particle flow code) numerical simulation method are used to investigate the crack mechanism of buried ground fissures in the loess layer. The results show that there are two main cracks in the layer profile, which have a Y-shape morphology. As the dip angle of the preset cracks increased from 60° to 90°, the main deformation zone at the surface gradually shifted towards the footwall. The process of crack propagation from depth to surface is divided into five stages. Additionally, the results confirm the accuracy of the width of the rupture zone d2in the footwall calculated by the cantilever beam theory. These findings can offer theoretical guidance for determining the avoidance distance of ground fissures in loess regions, as well as for implementing disaster prevention and corresponding control measures for various stages of buried ground fissure propagation.

关键词： Ground fissure Fenwei Basin Physical model test Particle flow code Crack propagation

Ectomycorrhizal fungi and dark septate endophyte inoculation improve growth and tolerance of Pinus tabulaeformis under cadmium stress

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Pedosphere 2024年第2期34卷 473-483页

作者： Yong ZHOU Yanyan ZHENG Pengwei li lingjie XU qiang FU College of Landscape Architecture and Tourism Hebei Agricultural UniversityBaoding 071000China

Forest trees can establish symbiotic associations with dark septate endophytes(DSEs)and ectomycorrhizal fungi(ECMF)***,the combined effects of these two fungi on the growth and cadmium(Cd)tolerance of host plants remain largely *** address this knowledge gap,a pot experiment was conducted to examine the effects of the interaction between an ECMF strain(Suillus granulatus)and a DSE strain(Pseudopyrenochaeta sp.)on Pinus tabulaeformis under Cd stress,by assessing plant growth and physiological parameters,nutrient uptake,and soil ***,the colonization rates of both fungal strains were found to increase in response to Cd stress,with the extent of this increase being influenced by the specific fungal species and the Cd level in the *** to the non-inoculation treatment,single inoculation with fungal strain resulted in enhanced biomass,root development,and nutrient contents in *** seedlings under Cd ***,a synergistic effect was observed when these seedlings were co-inoculated with *** and Pseudopyrenochaeta sp.,as indicated by significantly greater measurements in various indicators compared to both the single and non-inoculation *** inoculation effectively regulated the antioxidant defense responses and photosynthesis of *** seedlings subjected to Cd stress,particularly in the co-inoculation *** addition,fungal inoculation facilitated the Cd accumulation in ***,suggesting a promising potential for the implementation of bioremediation strategies in the areas contaminated with heavy *** findings from this study indicate that the utilization of root symbiotic fungi obtained from stress environments could potentially enhance the growth performance and tolerance of *** towards heavy metals,and co-inoculation of both fungal groups may result in even more pronounced synergistic effects on the overall fitness of the plant.

关键词： antioxidant defense response colonization rate fungal inoculation heavy metal tolerance physiological parameter root symbiotic fungi soil property

An anti-icing scaling method for wind tunnel tests of aircraft thermal ice protection system

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Chinese Journal of Aeronautics 2024年第6期37卷 1-6页

作者： Yu liU qiang WANG Xian YI Ningli CHEN Jinghao REN Weihao li Key Laboratory of Icing and Anti/de-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics Mianyang 621000China

The efficiency of the aircraft Ice Protection Systems(IPSs)needs to be verified through icing wind tunnel ***,the scaling method for testing the IPSs has not been systematically established yet,and further research is *** the present study,a scaling method specifically designed for thermal IPSs was derived from the governing equation of thin water *** scaling parameters were adopted to address the heat and mass transfer involved in the thermal anti-icing *** method validation,icing wind tunnel tests were conducted using a jet engine nacelle model equipped with a bleed air *** non-dimensional surface temperature and runback ice closely matched for both the reference and scaled *** validation confirms that the scaling method is capable of achieving the similarity of surface temperature and the runback ice *** anti-icing scaling method can serve as an important supplement to the existing icing similarity theory.

关键词： Scaling method Ice protection system Water film Anti-icing test Icing wind tunnel

Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China

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Journal of Arid Land 2024年第1期16卷 14-28页

作者： NAN Weige DONG Zhibao ZHOU Zhengchao li qiang CHEN Guoxiang School of Geography and Tourism Shaanxi Normal UniversityXi'an 710062China Shaanxi Key Laboratory of Ecological Restoration in Shaanbei Mining Area Yulin UniversityYulin 719000China College of Prataculture Gansu Agricultural UniversityLanzhou 730070China

Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid *** study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,*** collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the *** plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)*** results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and *** plantation age increased,silt and very fine sand contents progressively *** 16 years of planting,there was a marked reduction in the mean soil particle *** initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an *** positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p *** contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these *** findings ascertain that the plantation of *** requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical ***,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid *** research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China.

关键词： Sabina vulgaris plantation age soil physical and chemical properties soil particle size soil fertility vegetation restoration Mu Us Sandy Land

A novel high-Cr CoNi-based superalloy with superior high-temperature microstructural stability, oxidation resistance and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1373-1381页

作者： Xiaorui Zhang Min Zou Song Lu Longfei li Xiaoli Zhuang qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced MetalsUniversity of Science and Technology BeijingBeijing 100083China

A novel multicomponent high-Cr CoNi-based superalloy with superior comprehensive performance was prepared,and the evaluation of its high-temperature microstructural stability,oxidation resistance,and mechanical properties was conducted mainly using its cast polycrystalline *** results disclosed that the morphology of theγ′phase remained stable,and the coarsening rate was slow during the long-term aging at 900–1000℃.The activation energy forγ′precipitate coarsening of alloy 9CoNi-Cr was(402±51)kJ/mol,which is higher compared with those of CMSX-4 and some other Ni-based and Co-based ***,there was no indica-tion of the formation of topologically close-packed phases during this *** these factors demonstrated the superior microstructural stability of the *** mass gain of alloy 9CoNi-Cr was 0.6 mg/cm^(2) after oxidation at 1000℃ for 100 h,and the oxidation resistance was comparable to advanced Ni-based superalloys CMSX-4,which can be attributed to the formation of a continuous Al_(2)O_(3) protective ***,the compressive yield strength of this cast polycrystalline alloy at high temperatures is clearly higher than that of the conventional Ni-based cast superalloy and the compressive minimum creep rate at 950℃ is comparable to that of the conventional Ni-based cast superalloy,demonstrating the alloy’s good mechanical properties at high *** is partially because high Cr is bene-ficial in improving theγandγ′phase strengths of alloy 9CoNi-Cr.

关键词： CoNi-based superalloys microstructure coarsening oxidation mechanical properties

Heteroatom anchors Fe-Mn dual-atom catalysts with bi-functional oxygen catalytic activity for low-temperature rechargeable flexible Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 610-620,I0014页

作者： Yuting He Hongtao li Yi Wang Yufei Jia Yongning liu qiang Tan State Key Laboratory for Mechanical Behaviour of Materials School of Materials Science&EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

M-N-C(M=Fe,Co,Ni,etc.) catalyst owns high catalytic activity in the oxygen catalytic reaction which is the most likely to replace the Pt-based *** it is still a challenge to further increase the active site *** article constructs the high-efficiency FeMn-N/S-C-1000 catalyst to realize ORR/OER bifunctional catalysis by hetero-atom,bimetal(Fe,Mn) doped simultaneously *** evaluated it as bi-functional electro-catalysts,FeMn-N/S-C-1000 exhibits excellent catalytic activity(E_(1/2)=0.924 V,E_(j=10)=1.617 V) in alkaline media,outperforms conventional Pt/C,RuO_(2) and most non-precious-metal catalysts reported recently,Such outstanding performance is owing to N,S co-coordinated with metal to form multi-types of single atom,dual atom active sites to carry out ***,nitrite poison test provides the proof that the active sites of FeMn-N/S-C are more than that of single-atom catalysts to promote catalytic reactions *** better understand the local structure of Fe and Mn active sites,XAS and DFT were employed to reveal that FeMn-N_5/S-C site plays the key role during ***,the FeMn-N/S-C-1000 based low-temperature rechargeable flexible Zn-air also exhibits superior discharge performance and extraordinary durability at-40℃.This work will provide a new idea to design diatomic catalysts applied in low-temperature rechargeable batteries.

关键词： Fe Mn-N/S-C-1000 ORR OER Rechargeable flexible Zn-air batteries