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Superior piezoelectric performance with high operating temperature in bismuth ferrite-based ternary ceramics

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Journal of Materials Science & Technology 2024年第2期169卷 172-181页

作者： Yunyao Huang Leiyang Zhang Ruiyi jing yang yang Vladimir Shur Xiaoyong Wei Li jin Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg620000Russia

Due to the thermal depolarization effect,adequate piezoelectric performance with high operating temperature is regarded to be challenging to accomplish concurrently in piezoceramics for applications in specific piezoelectric *** this work,we synthesized(0.8−x)BiFeO_(3)-x PbTi_(3)-0.2Ba(Zr_(0.25)Ti_(0.75))O_(3)(abbreviated as BFO-x PT-BZT)ternary solid solutions with 0.15≤x≤0.30 by conventional solid-state reaction *** MPB composition with a coexisting state of rhombohedral-tetragonal phases exhibits enhanced electromechanical properties,including Curie temperature of 380℃,large-signal equivalent piezoelectric coefficient d^(∗)_(33)of 395 pm V^(-1),small-signal piezoelectric coefficient d_(33)of 302 pC N^(-1),and electromechanical coupling factor k_(p)of 50.2%,which is comparable to commercial PZT-5A ceramics,indicating potential in high-temperature ***,in-situ X-ray diffraction(XRD)and piezoelectric force microscopic(PFM)techniques demonstrate that multiphase coexistence and complex nanodomains promote piezoelectric response via *** x=0.24 composition exhibits the highest in-situ d_(33)of 577 pC N^(-1)and good temperature stability in 30−280℃,indicating that BZT-modified BFO-PT ceramics are promising candidates for high-temperature piezoelectric devices.

关键词： High-temperature piezoelectrics Morphotropic phase boundary In-situ technique Domain structure BFO

Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： jin-guo Gao Shu-lei yang Shu-feng yang jing-she Li Wei Liu Meng-jing Zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

Achieving high-performance sodium metal anodes: From structural design to reaction kinetic improvement

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Nano Research 2024年第3期17卷 1288-1312页

作者： jing Xu Jianhao yang Yashuang Qiu yang jin Tianyi Wang Bing Sun Guoxiu Wang Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China College of Chemistry and Chemical Engineering yangzhou University Yangzhou 225009China Centre for Clean Energy Technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia

Sodium metal is one of the ideal anodes for high-performance rechargeable batteries because of its high specific capacity(~1166 mAh·g^(-1)),low reduction potential(-2.71 V compared to standard hydrogen electrodes),and low ***,the unstable solid electrolyte interphase,uncontrolled dendrite growth,and inevitable volume expansion hinder the practical application of sodium metal *** present,many strategies have been developed to achieve stable sodium metal ***,we systematically summarize the latest strategies adopted in interface engineering,current collector design,and the emerging methods to improve the reaction kinetics of sodium deposition ***,the strategies of constructing protective layers are reviewed,including inorganic,organic,and mixed protective layers through electrolyte additives or ***,the classification of metal-based,carbon-based,and composite porous frames is discussed,including their function in reducing local deposition current density and the effect of introducing sodiophilic ***,the recent progress of alloys,nanoparticles,and single atoms in improving Na deposition kinetics is systematically ***,the future research direction and the prospect of high-performance sodium metal batteries are proposed.

关键词： sodium metal anodes interface engineering current collector design reaction kinetics sodium deposition processes

Ni-Cu bimetallic alloy anchored on nitrogen-doped carbon nanotubes for CO_(2)-to-CH_(4) electrochemical conversion

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Nano Research 2024年第8期17卷 6922-6930页

作者： jing Li Chuanyong jing jin Wang School of Environment Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality SafeguardBeijing Jiaotong UniversityBeijing 100044China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Tangshan Research Institute Beijing Jiaotong UniversityTangshan 063000China

Electrocatalytic CO_(2) reduction to CH_(4) remains challenging due to multi-electron transfer and intermediates ***,we synthesized electrocatalysts by growing Ni-Cu alloy structure on nitrogen-doped carbon nanotubes(NixCuy-NCNT)for electrocatalytic CO_(2) reduction reaction(CO_(2)RR)via hydrothermal method followed by *** optimized Ni_(1)Cu_(1)-NCNT demonstrated a superior CO_(2)RR performance,achieving 99.7%FECH_(4)(FE=Faradaic efficiency)and 11.54 mA·cm^(−2) current density at−1.2 V *** hydrogen electrode(RHE),which outperformed single metal *** outstanding performance was due to the electrons transferred from Cu to Ni and Ni-Cu alloy shifted the d-band center toward the Fermi level,which was more conducive to the intermediate *** situ electrochemical attenuated total reflection(EC-ATR)and density functional theory(DFT)calculations revealed the appearance of *CHO intermediate and the pathway during the CO_(2)RR *** design of the bimetallic electrocatalyst in this study provides a new perspective for the highly selective reduction of CO_(2).

关键词： electrocatalytic CO_(2) reduction Ni-Cu alloy nitrogen-doped carbon nanotube(NCNT) electrochemical attenuated total reflection(EC-ATR) density functional theory(DFT)calculations

Precisely Control Relationship between Sulfur Vacancy and H Absorption for Boosting Hydrogen Evolution Reaction

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Nano-Micro Letters 2024年第4期16卷 14-24页

作者： jing jin Xinyao Wang yang Hu Zhuang Zhang Hongbo Liu Jie Yin Pinxian Xi College of Chemistry and Chemical Engineering Frontiers Science Center for Rare IsotopesState Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000People’s Republic of China

Ef fective and robust catalyst is the core of water splitting to produce ***, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.

关键词： Hydrogen evolution reaction S vacancies Nanosheet H Adsorption

Catalytic Reaction Kinetics of Propylene Dimerization to 4-Methyl-1-Pentene Using Cu-K/K_(2)CO_(3) Solid Base Catalyst

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 78-87页

作者： jin Haibo Chai jing yang Suohe He Guangxiang Ma Lei Guo Xiaoyan College of New Materials and Chemical Engineering Beijing Institute of Petrochemical Technology/Beijing Key Laboratory of Fuel Cleaning and Efficient Catalytic Emission Reduction TechnologyBeijing102617China

The catalysis technology of propylene dimerization to form 4-methyl-1-pentene(4MP1)using a Cu-K/K_(2)CO_(3) solid base catalyst is a well-known heterogeneous catalytic *** this study,the intrinsic kinetics of propylene dimerization were studied in a fixed-bed continuous *** and external diffusion during the dimerization reaction experiments were eliminated by adjusting the flow rate of the carrier gas and the particle size of the catalyst ***,the concentration changes of each substance at the outlet of the catalyst bed under different residence times were ***,the suitable reaction kinetics equations was derived using the Langmuir Hinshelwood-Hougen-Watson kinetic ***,the activation energy for each reaction involved in the dimerization reaction was *** activation energies of 4MP1,branched by-products,and 1-hexene were 115.0,150.8,and 177.4 kJ/mol,*** effect of process conditions on propylene dimerization with solid base catalysts was studied through kinetic model *** comparing the theoretical values obtained from the simulation with the experimental results,the applicability and accuracy of the kinetic model were verified.

关键词： propylene dimerization 4-methyl-1-pentene intrinsic kinetics surface reaction

Production induced fracture closure of deep shale gas well under thermo-hydro-mechanical conditions

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Petroleum Science 2024年第3期21卷 1796-1813页

作者： Shi-Ming Wei yang Xia Yan jin Xu-yang Guo jing-Yu Zi Kai-Xuan Qiu Si-Yuan Chen College of Science China University of Petroleum(Beijing)Beijing102249China CNOOC Research Institute Ltd Beijing100028China The University of Hong Kong Hong Kong999077China

Deep shale gas reservoirs have geological characteristics of high temperature,high pressure,high stress,and inferior ability to pass through *** multi-stage fractured horizontal well is the key to exploiting the deep shale gas ***,during the production process,the effectiveness of the hydraulic fracture network decreases with the closure of fractures,which accelerates the decline of shale gas *** this paper,we addressed the problems of unclear fracture closure mechanisms and low accuracy of shale gas production prediction during deep shale gas *** we established the fluid—solid—heat coupled model coupling the deformation and fluid flow among the fracture surface,proppant and the shale *** the fluid—solid—heat coupled model was applied to the fracture network,it was well solved by our numerical method named discontinuous discrete fracture *** with the conventional discrete fracture method,the discontinuous discrete fracture method can describe the three-dimensional morphology of the fracture while considering the effect of the change of fracture surface permeation coefficient on the coupled fracture—matrix flow and describing the displacement discontinuity across the *** simulations revealed that the degree of fracture closure increases as the production time proceeds,and the degree of closure of the secondary fractures is higher than that of the primary *** creep and proppant embedment both increase the degree of fracture *** reduction in fracture surface permeability due to proppant embedment reduces the rate of fluid transfer between matrix and fracture,which has often been overlooked in the ***,it significantly impacts shale gas production,with calculations showing a 24.7%cumulative three-year yield *** study is helpful to understand the mechanism of hydraulic fracture ***,it provides the theoretical guidance for maintaining the long

关键词： Shalegas Fracture closure Fluid-solid-heat coupling Discontinuous discrete fracture

Tau truncation in the pathogenesis of Alzheimer's disease:a narrative review

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Neural Regeneration Research 2024年第6期19卷 1221-1232页

作者： Dandan Chu Xingyue yang jing Wang Yan Zhou jin-Hua Gu jin Miao Feng Wu Fei Liu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsCoinnovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Department of Biochemistry and Molecular Biology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Clinical Pharmacy Affiliated Maternity and Child Health Care Hospital of Nantong UniversityNantong UniversityNantongJiangsu ProvinceChina Laboratory of Animal Center Nantong UniversityNantongJiangsu ProvinceChina Department of Neurochemistry Inge Grundke-Iqbal Research FloorNew York State Institute for Basic Research in Developmental DisabilitiesStaten IslandNYUSA

Alzheimer's disease is characterized by two major neuropathological hallmarks—the extracellularβ-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau *** studies suggest that dysregulation of the microtubuleassociated protein Tau,especially specific proteolysis,could be a driving force for Alzheimer's disease *** physiologically promotes the assembly and stabilization of microtubules,whereas specific truncated fragments are sufficient to induce abnormal hyperphosphorylation and aggregate into toxic oligomers,resulting in them gaining prion-like *** addition,Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent *** review summarizes over 60 proteolytic cleavage sites and their corresponding truncated fragments,investigates the role of specific truncations in physiological and pathological states of Alzheimer's disease,and summarizes the latest applications of strategies targeting Tau fragments in the diagnosis and treatment of Alzheimer's disease.

关键词： Alzheimer's disease cleavage site diagnosis marker neurofibrillary tangles phosphorylation Tau Tau aggregation therapy truncation

Total Synthesis and Stereochemical Assignment of Talaroconvolutin A and Talarofuranone: Gram-scale Synthesis of Ferroptosis Inducer Talaroconvolutin A

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Chinese Journal of Chemistry 2024年第13期42卷 1509-1514页

作者： Ming Yao Wei yang jing Li Chengyun Huang jin Fang Sulu Qin Shuzhi Liu Xiaolong yang School of Pharmaceutical Sciences South-Central Minzu UniversityWuhanHubei 430074China

The first total synthesis of talaroconvolutin A(1.1 g obtained)and talarofuranone has been achieved using accessible materials(12 steps,7.5%and 8.2%yields,respectively).Convergent routes involved intramolecular Diels-Alder reactions in two approaches for creating the decalin ***,an unprecedented DMP-mediated domino reaction resulted in the deoxy-tetramic acid *** syntheses not only establish the absolute configuration of talaroconvolutin A but also enable further collaborative studies of this typeofferroptosisinducers.

关键词： Natural products Aldehydes Total synthesis Domino reactions Biological activity Antitumor agents Ferroptosis Diels-Alder reaction Talaroconvolutin A