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Investigation on crystallization behavior between(Sc_(x)Yb_(1−x))O_(1.5)and CMAS:A new insight in the effect of Sc substitution

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Journal of Advanced Ceramics 2024年第6期13卷 789-799页

作者： Guangheng zhang Jinyu Shi Jie zhang Jingyang Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Environmental barrier coatings(EBCs)with thermomechanical robustness against calcium–magnesium–aluminum–silicate(CMAS)deposits are in high *** aim of this work was to clarify the influence of Sc^(3+)on the crystallization behavior of Yb-based coatings against CMAS *** reaction products of solid solutions with compositions traversing the Sc_(2)O_(3)–Yb_(2)O_(3)system indicate that Sc^(3+)tends to form[BO_(6)]coordination polyhedra in the crystal structure to promote the formation of garnet and diopside,while Yb^(3+)occupies 7-,8-,and 9-coordinate sites to crystallize apatite and *** transformation of crystalline products from apatite/silicocarnotite to garnet/diopside greatly improves the efficiency of CMAS melt consumption and facilitates the prevention of its further penetration and *** on the commonality of cation occupancy in crystallography,an A(CaO+YbO_(1.5))–B(ScO_(1.5)+MgO+AlO_(1.5))–T(SiO_(2))pseudoternary phase diagram is established,which has great potential for describing phase equilibrium in coating-deposit systems and can provide guidance for the compositional design of corrosion-resistant coatings.

关键词： crystallization behavior cation partitioning scandium-ytterbium oxide(Sc_(x)Yb_(1−x))O_(1.5)solid solution calcium-magnesium-aluminum-silicate(CMAS)deposit pseudoternary phase diagram

Protective benefit of folded linear HDPE board sand fences along the Golmud-Korla Railway,China:Field observation and wind tunnel study

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Journal of Mountain Science 2024年第7期21卷 2206-2219页

作者： zhang Kai TIAN Jianjin WANG Zhenghui zhang Hailong zhang Xingxin College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Civil Engineering Chongqing UniversityChongqing 400045China

The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction *** study introduced a novel sand fence deployment technique,termed‘folded linear deployment',designed to position the sand fence orthogonally to the two predominant wind directions for optimal *** study used wind tunnel and field tests to evaluate the wind and sand flow characteristics,as well as the windproof and sandresistant performance of folded linear HDPE(Highdensity polyethylene)board sand *** results suggest that the airflow around the fence creates clear zoning *** deceleration area on the BSF(backwind side of the sand fence)is much larger than that on the DSF(downwind side of the sand fence).Thus,sand particles are primarily deposited on the *** different wind speeds,the airflow at 2 and 5 h on the DSF is not *** WSP(wind speed profile)presents a logarithmic *** airflow is disturbed at 1-20 h on the BSF,and the WSP gradually deviates from the logarithmic ***,as the airflow moves away from the fence,the WSP gradually approaches a logarithmic ***,the WPE(windproof efficiency)and SRE(sand-resistant efficiency)of the sand fence exceed 80%.In addition,the results of wind tunnel tests are compared with those of field *** overall dispersion is good,and the best dispersion is found at z/H=2.00,indicating good agreement between the two test *** study provides a scientific basis for the design of sand hazard control measures,similar to the railway project in the Gobi Gale area.

关键词： Folded linear HDPE board sand fence Double wind direction Gobi area Protection benefit

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han zhang You Lu Sheng-gui zhang Li zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈EG(u)U{u}φ(z)≠Σz∈EG(v)U{v}φ(z)for each edge uv∈E(G),where EG(u)is the set of edges incident with a vertex *** 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-***,Yang et *** that the conjecture holds for planar graphs withΔ≥10,and Qu et *** that the list version of the conjecture also holds for planar graphs withΔ≥*** this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： Xun WEI Yan zhang Xuefa SHI Hui zhang Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle *** seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are *** this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic *** lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and *** with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile *** lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle *** are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic *** isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga *** occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev *** to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle *** propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah *** Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle conve

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension

High-efficiently doping nitrogen in kapok fiber-derived hard carbon used as anode materials for boosting rate performance of sodium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 472-482页

作者： Tianyun zhang Tian zhang Fujuan Wang Fen Ran School of Mechanical and Electronical Engineering Lanzhou University of TechnologyLanzhou 730050GansuChina State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals School of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730500GansuChina

The engineering of plant-based precursor for nitrogen doping has become one of the most promising strategies to enhance rate capability of hard carbon materials for sodium-ion batteries;however,the poor rate performance is mainly caused by lack of pyridine nitrogen,which often tends to escape because of high temperature in preparation process of hard *** this paper,a high-rate kapok fiber-derived hard carbon is fabricated by cross-linking carboxyl group in 2,6-pyridinedicarboxylic acid with the exposed hydroxyl group on alkalized kapok with assistance of zinc ***,a high nitrogen doping content of 4.24%is achieved,most of which are pyridine nitrogen;this is crucial for improving the defect sites and electronic conductivity of hard *** optimized carbon with feature of high nitrogen content,abundant functional groups,degree of disorder,and large layer spacing exhibits high capacity of 401.7 mAh g^(−1)at a current density of 0.05 A g^(−1),and more importantly,good rate performance,for example,even at the current density of 2 A g^(−1),a specific capacity of 159.5 mAh g^(−1)can be *** findings make plant-based hard carbon a promising candidate for commercial application of sodium-ion batteries,achieving high-rate performance with the enhanced pre-cross-linking interaction between plant precursors and dopants to optimize aromatization process by auxiliary pyrolysis.

关键词： Kapok fiber Hard carbon Electrode materials Rate performance Sodium-ion batteries

Hard carbon for sodium storage:Mechanism and performance optimization

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Nano Research 2024年第7期17卷 6038-6057页

作者： Yongxin Wang Meng Li Yu zhang Naiqing zhang State Key Laboratory of Urban Water Resource and Environment School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Due to the shortage of lithium resource reserves and the pressure of rising prices,sodium-ion batteries have regained the attention of the public,and shown great potential for application in the fields of grid energy storage and low-speed vehicles to achieve the purpose of complementing lithium-ion batteries,so it is imperative to promote the commercial application of sodiumion *** sodium-ion battery anode materials,hard carbon is the material most likely to be used ***,there is still much work to be done before its *** review provides a comprehensive overview of the current research status from the following three ***,the microstructure and sodium storage active sites of hard carbon are ***,the mechanism of sodium storage in hard carbon is investigated,which can be broadly categorized into four model,“insertion–filling”,“adsorption–insertion”,“adsorption–filling”,and“multistage”.Finally,from the perspective of improving the electrochemical performance of hard carbon,the performance improvement strategies proposed in recent years are *** with the performance of hard carbon commercial products of some enterprises,the future development goal of hard carbon is prospected,hoping that all sectors of society can work hard for this common goal.

关键词： sodium-ion battery hard carbon mechanism performance optimization

Advances in doping strategies for sodium transition metal oxides cathodes:A review

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Frontiers in Energy 2024年第2期18卷 141-159页

作者： Zhijing zhang Haoze zhang Yaopeng WU Wei YAN Jiujun zhang Yun ZHENG Lanting QIAN Department of Chemical Engineering Waterloo Institute of NanotechnologyUniversity of WaterlooWaterloo ON N2L 3G1Canada School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China Institute of New Energy Materials Science and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

The electrochemistry of cathode materials for sodium-ion batteries differs significantly from lithium-ion batteries and offers distinct ***,the progress of commercializing sodium-ion batteries is currently impeded by the inherent inefficiencies exhibited by these cathode materials,which include insufficient conductivity,slow kinetics,and substantial volume changes throughout the process of intercalation and deintercalation ***,numerous methodologies have been utilized to tackle these challenges,encompassing structural modulation,surface modification,and elemental *** paper aims to highlight fundamental principles and strategies for the development of sodium transition metal oxide ***,it emphasizes the role of various elemental doping techniques in initiating anionic redox reactions,improving cathode stability,and enhancing the operational voltage of these cathodes,aiming to provide readers with novel perspectives on the design of sodium metal oxide cathodes through the doping approach,as well as address the current obstacles that can be overcome/alleviated through these dopant strategies.

关键词： sodium-ion batteries transition metal cathode doping strategy

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单相单级式耦合电感型分裂源升压逆变器

中国电机工程学报 2024年第9期44卷 3679-3690,I0029页

作者：朱小全叶开文金科周玮阳张波南京航空航天大学自动化学院江苏省南京市210016 华南理工大学电力学院广东省广州市510641

面对全球资源日渐紧缺、环境问题日益严重、传统化石能源开发利用越发困难等新挑战,世界各国都在大力探索、发展新能源发电技术,以新能源为主体的新型电力系统是未来电力系统的发展方向。该文提出一种单相单级式耦合电感型分裂源升压逆... 详细信息

面对全球资源日渐紧缺、环境问题日益严重、传统化石能源开发利用越发困难等新挑战,世界各国都在大力探索、发展新能源发电技术,以新能源为主体的新型电力系统是未来电力系统的发展方向。该文提出一种单相单级式耦合电感型分裂源升压逆变器及其调制策略,所提出的变换器具有如下特点:1)采用Δ型耦合电感,极大地提升变换器的输出电压增益,并具有高输出电压增益调节自由度。2)采用双Buck结构,有效抑制逆变桥臂直通电流,降低死区时间配置要求,提高变换器可靠性。3)高输出电压增益条件下具有高调制系数,从而有效提升输出电压波形质量。该文对该变换器的拓扑结构、工作原理、调制策略和输出特性等进行详细分析,通过仿真与实验验证变换器的可行性与有效性。

关键词：分裂源逆变器双Buck结构高增益升压逆变器

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting zhang Chenyi Fang J Paul Chen Sui zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering