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怀山药连作地土壤元素的变化和连作障碍解决方法研究

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安徽农业科学 2024年第2期52卷 161-164页

作者：王帆林王代军成宏斌潘晓翠海南省农垦科学院集团有限公司海南三亚572024

测定和分析温县怀山药栽培基地土壤元素随连作年限的变化,分离鉴定怀山药根际土中化感物质的种类和含量,探究引起怀山药连作障碍的主要因素,并考察施用杀线菌肥对山药产量和品质的影响。结果表明:怀山药连作1~4年土壤元素和有机质含量... 详细信息

测定和分析温县怀山药栽培基地土壤元素随连作年限的变化,分离鉴定怀山药根际土中化感物质的种类和含量,探究引起怀山药连作障碍的主要因素,并考察施用杀线菌肥对山药产量和品质的影响。结果表明:怀山药连作1~4年土壤元素和有机质含量先增多后减少,以连作2年最高,连作使土壤氮、磷、钾比例失调,Cu、Cd、Cr、Ni、Pb在土壤表层富集,土壤pH减小。随着生长期的延长,土壤中全磷、重金属、Na含量降低,全钾、Ca增多,Mg和有机质变化不明显;应用GC-MS和HPLC在山药根际土中共鉴定出11种化感物质。施用杀线菌肥可有效缓解山药连作障碍,达到增产提质防病害的功效,以3000 kg/hm^(2)效果最优,比对照增产26.83%,根长增加35.26%,畸形率降低82.43%;3000、6000和9000 kg/hm^(2)施肥量使山药增粗10.00%~15.00%,根际线虫分别比对照减少了82.80%、73.12%和52.69%。

关键词：怀山药连作障碍土壤元素杀线菌肥

Micro-macro evolution of mechanical behaviors of thermally damaged rock:A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2833-2853页

作者： Yunmin wang jun Peng Linfei wang Chuanhua Xu Bibo dai State Key Laboratory of Safety and Health for Metal Mines Sinosteel Maanshan General Institute of Mining Research Co.Ltd.Maanshan243000China

The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock *** the rocks are subjected to thermal treatment,the change of macroscopic characteristics and evolution of micro-structure would be induced,ultimately resulting in different degrees of thermal damage in *** better understand the thermal damage mechanism of different rocks and its effect on the rock performance,this study reviews a large number of test results of rock specimens experiencing heating and cooling treatment in the ***,the variations of macroscopic behaviors,including physical parameters,mechanical parameters,thermal conductivity and permeability,are *** variations of mechanical parameters with thermal treatment variables(*** or the number of thermal cycles)are divided into four ***,several measuring methods for microstructure,such as polarizing microscopy,fluorescent method,scanning electron microscopy(SEM),X-ray computerized tomography(CT),acoustic emission(AE)and ultrasonic technique,are ***,the effect of thermal damage on the mechanical parameters of rocks in response to different thermal treatments,involving temperature magnitude,cooling method and thermal cycle,are ***,the limitations and prospects for the research of rock thermal damage are proposed.

关键词： Thermal damage Macroscopic characteristics Microstructure evolution Temperature magnitude Cooling method Thermal cycle

Resolving aging dynamics of a 3D colloidal glass

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 110-118页

作者： XiaoJuan wang jun Duan Gan Ding YunZhuo Lu Xing Lu LanHong dai MinQiang Jiang State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak is reproduced at low *** findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.

关键词： colloidal glass physical aging particle dynamics free volume boson peak

Bifunctional core–shell co-catalyst for boosting photocatalytic CO_(2) reduction to CH_(4)

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Nano Research 2024年第3期17卷 1259-1266页

作者： Fangxu dai Mingming Zhang Jishu Han Zhenjiang Li Shouhua Feng jun Xing Lei wang Key Laboratory of Eco-chemical Engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China College of Environment and Safety Engineering Qingdao University of Science and TechnologyShandong Engineering Research Center for Marine Environment Corrosion and Safety ProtectionQingdao 266042China

Solar-light-driven CO_(2) reduction CO to CH_(4) and C2H6 is a complex process involving multiple elementary reactions and energy ***,achieving high CH_(4) activity and selectivity remains a significant ***,we integrate bifunctional Cu2O and Cu-MOF(MOF=metal-organic framework)core–shell co-catalysts(Cu2O@Cu-MOF)with semiconductor TiO_(2).Experiments and theoretical calculations demonstrate that Cu2O(Cu+facilitates charge separation)and Cu-MOF(Cu2+improves the CO_(2) adsorption and activation)in the core–shell structure have a synergistic effect on photocatalytic CO_(2) reduction,reducing the formation barrier of the key intermediate*COOH and**** photocatalyst exhibits high CH_(4) yield(366.0μmol·g^(-1)·h^(-1)),efficient electron transfer(3283μmol·g^(-1)·h^(-1))and hydrocarbon selectivity(95.5%),which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO_(2) reduction *** work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components.

关键词： bifunctional co-catalyst core–shell photocatalytic CO_(2)reduction

Asymmetric orbital hybridization in Zn-doped antiperovskite Cu_(1-x)Zn_(x)NMn_(3)enables highly efficient electrocatalytic hydrogen production

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Journal of Energy Chemistry 2024年第2期89卷 304-312,I0008页

作者： Yuxiang Yan Yuxin Cao Zhichao wang Ka wang Hengdong Ren Shaoqi Zhang Yi wang Jian Chen Yong Zhou Lizhe Liu jun dai Xinglong Wu National Laboratory of Solid States Microstructures and School of Physics Nanjing UniversityNanjing 210093JiangsuChina College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093JiangsuChina National Laboratory of Solid States Microstructures and Research Institute of Superconductor Electronics Nanjing UniversityNanjing 210093JiangsuChina School of Mathematics&Physics Jiangsu University Science&TechnologyZhenjiang 212003JiangsuChina

Rational design of efficient and robust earth-abundant alkaline hydrogen evolution reaction(HER)catalysts is a key factor for developing energy conversion ***,antiperovskite nitride CuNMn_(3)has garnered significant interest due to its remarkable properties such as negative/zero thermal expansion and magnetocaloric ***,when utilized as hydrogen evolution catalysts,it encounters large challenge resulting from excessively strong/weak interactions with adsorbed H on Mn/Cu active sites,which leads to low HER *** this study,we introduce an asymmetric orbital hybridization strategy in Zn-doped Cu_(1-x)Zn_(x)NMn_(3)by leveraging the localization of Zn electronic states to reconfigure the electronic structures of Cu and Mn,thereby reducing the energy barrier for water dissociation and optimizing Cu and Mn active sites for hydrogen adsorption and H_(2)*** evaluations reveal that Cu_(0.85)Zn_(0.15)NMn_(3)with x=0.15 demonstrates exceptional electrocatalytic activity in alkaline electrolytes.A low overpotential of 52 mV at 10 mA cm^(-2)and outstanding stability over a 150-h test period are achieved,surpassing commercial Pt/*** research offers a novel strategy for enhancing HER performance by modulating asymmetric hybridization of electron orbitals between multiple metal atoms within a material structure.

关键词： Cu_(1-x)ZnxNMn_(3) Asymmetric orbital hybridization Hydrogen adsorption Hydrogen production

An Efficient Optimization Design Framework for Low-Resistance Shape of Bionic Amphibious Robot

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China Ocean Engineering 2024年第1期38卷 117-128页

作者： ZHANG dai-yu ZHANG Man-yu wang Zhi-dong ZHENG Wen-sheng LING Hong-jie HU jun-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

To realize the low-resistance shape optimization design of amphibious robots,an efficient optimization design framework is proposed to improve the geometric deformation flexibility and optimization *** the proposed framework,the free-form deformation parametric model of the flat slender body is established and an analytical calculation method for the height constraints is *** method is introduced to carry out the high-precision resistance calculation and a constrained Kriging-based optimization method is built to improve the optimization efficiency by circularly infilling the new sample points which satisfying the ***,the shape of an amphibious robot example is optimized to get the low-resistance shape and the results demonstrate that the presented optimization design framework has the advantages of simplicity,flexibility and high efficiency.

关键词： amphibious robot optimization method free-form deformation CFD-based hydrodynamic calculation

Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National Science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang Yuxin Hao Bei wang Yan wang Liping Zheng Rui Li Huige Ma Xinyu wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui wang Yujie dai Guangcun Shan Mingjun Hu jun Luo jun Yang School of Materials Science and Engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science & TechnologyGuangxi University School of Chemistry and Chemical Engineering Center on Nanoenergy Research Guangxi University School of Instrumentation Science and Opto-electronics Engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their ***,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable *** has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of *** to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than ***,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in ***,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery

Strain‑Induced Surface Interface Dual Polarization Constructs PML‑Cu/Bi_(12)O_(17)Br_(2) High‑Density Active Sites for CO_(2) Photoreduction

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Nano-Micro Letters 2024年第5期16卷 169-183页

作者： Yi Zhang Fangyu Guo jun Di Keke wang Molly Meng‑jung Li Jiayu dai Yuanbin She Jiexiang Xia Huaming Li School of Chemistry and Chemical Engineering Institute for Energy ResearchSchool of the Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013People’s Republic of China State Key Laboratory Breeding Base of Green Chemistry‑Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014People’s Republic of China College of Science and Hunan Key Laboratory of Extreme Matter and ApplicationsNational University of Defense TechnologyChangsha 410073People’s Republic of China Department of Applied Physics The Hong Kong Polytechnic UniversityHung HomHong KongPeople’s Republic of China School of Chemistry and Chemical Engineering National Special Superfine Powder Engineering Research CenterNanjing University of Science and TechnologyNanjing 210094People’s Republic of China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Zhejiang Normal UniversityJinhua 321004People’s Republic of China

The insufficient active sites and slow interfacial charge trans-fer of photocatalysts restrict the efficiency of CO_(2) *** synchronized modulation of the above key issues is demanding and ***,strain-induced strategy is developed to construct the Bi–O-bonded interface in Cu porphyrin-based monoatomic layer(PML-Cu)and Bi_(12)O_(17)Br_(2)(BOB),which triggers the surface interface dual polarization of PML-Cu/BOB(PBOB).In this multi-step polarization,the built-in electric field formed between the interfaces induces the electron transfer from con-duction band(CB)of BOB to CB of PML-Cu and suppresses its reverse ***,the surface polarization of PML-Cu further promotes the electron converge in Cu *** introduction of PML-Cu endows a high density of dispersed Cu active sites on the surface of PBOB,significantly promoting the adsorption and activation of CO_(2) and CO *** conversion rate of CO_(2) photoreduction to CO for PBOB can reach 584.3μmol g-1,which is 7.83 times higher than BOB and 20.01 times than *** work offers valuable insights into multi-step polarization regulation and active site design for catalysts.

关键词： Bi_(12)O_(17)Br_(2) Porphyrin CO_(2)photoreduction Polarization Active sites

Oxidation resistant low-alloyed Ti alloys with good ductility

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Rare Metals 2024年第8期43卷 3921-3936页

作者： Meng Li Zhang-Zhi Shi jun-Yi Xu Fu-Zhi dai Xiang-Min Li Zi-Lin Li Lu-Ning wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advance Metals and MaterialsSchool of Materials Science and Engineering University of Science and Technology Beijing Institute of Materials Intelligent Technology Liaoning Academy of Materials

Oxidation resistance enhancement of pure Ti often comes at the cost of reduced ductility,which is frequently the problem through alloying with sole Al,Si,W,Mo and *** overcome the short coming of single element alloying,this paper proposes a multi-element low-alloying strategy to take advantage of synergistic effects and resolve the conflict between oxidation resistance and *** demonstrates that the addition of a small quantity of Ta（0.51wt%） can boost both oxidation resistance and ductility in comparison to pure ***,the combined addition of a small amount（0.54 wt%） of Ta,Nb and Si not only preserves good ductility of pure Ti,but also reduces mass gains to 14%-67% of pure Ti during 100 h oxidation at 650-850℃ in *** indicates even better oxidation resistance than that obtained through the use of Ta,Nb,or Nb+Ta *** Ta+Nb+Si alloying creates an oxide layer that is less porous and more resistant to stratification and ***,a 3-μm N-rich layer can form in the Ti substrate beneath the oxide scale,in which phase transformation generates coherent Ti2N with（0001）Tias the habit plane,with N atoms prefers to diffuse along ■ than along [0001]*** completely transformed Ti2N region or partially transformed Ti+Ti2N region can effectively impede oxygen ***,the multielement low-alloying strategy is promising for enhancing both oxidation resistance and mechanical properties of metallic materials in the future.

关键词： Ti alloys Multi-element Co-alloying Oxidation resistance Mechanical properties