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Multiphase Interfacial Regulation Based on Hierarchical Porous Molybdenum Selenide to Build Anticorrosive and Multiband Tailorable Absorbers

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nano-Micro Letters 2024年第1期16卷 85-105页

作者： Tianbao zhao Zirui Jia Jinkun Liu yan Zhang Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071People’s Republic of China

Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution *** in order to cope with the complex electromagnetic environment,the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous *** this work,we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the ***,through interfacial engineering,a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the *** analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial ***,the prepared MoSe_(2)/MoC/PNC composites showed excellent EMW absorption performance in C,X,and Ku bands,especially exhibiting a reflection loss of−59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 *** coordination between structure and components endows the absorber with strong absorption,broad bandwidth,thin thickness,and multi-frequency absorption ***,it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel *** study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers,and provides a reference for the design of multifunctional,multiband EMW absorption materials.

关键词： Interfacial engineering Anticorrosion Multiband Electromagnetic wave absorber

Qualitative analysis of aromatic compounds via 1D TOCSY techniques

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Magnetic Resonance Letters 2024年第1期4卷 21-27页

作者： Wenbo Dong Qi zhao Jiancheng zhao Jiarong Zhang Yingxiong Wang yan Qiao State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China Graduate University of Chinese Academy of Sciences Beijing100049China Marine Biomedical Research Institution Guangdong Medical UniversityZhanjiang524023China College of Chemistry Taiyuan University of Technology79 Yingze West StreetWanbailin DistrictTaiyuan030024China

The aromatic compounds,including o-xylene,m-xylene,p-xylene,and ethylbenzene,primarily originate from the catalytic reforming of crude oil,and have a wide variety of ap***,because of similar physical and chemical properties,these compounds are difficult to be identified by gas chromatography(GC)without standard *** the development of modern nuclear magnetic resonance(NMR)techniques,NMR has emerged as a powerful and efficient tool for the rapid analysis of complex and crude mixtures without *** this study,the parameters of one-dimensional(1D)total correlation spectroscopy(TOCSY)NMR techniques,including 1D selective gradient TOCSY and 1D chemicalshift-selective filtration(CSSF)with TOCSY,were optimized to obtain comprehensive molecular structure *** results indicate that the overlapped signals in NMR spectra of nonpolar aromatic compounds(including o-xylene,m-xylene,p-xylene and ethylbenzene),polar aromatic compounds(benzyl alcohol,benzaldehyde,benzoic acid),and aromatic compounds with additional conjugated bonds(styrene)can be resolved in 1D *** importantly,full molecular structures can be clearly distinguished by setting appropriate mixing time in 1D *** approach simplifies the NMR spectra,provides structural information of entire molecules,and can be applied for the analysis of other structural isomers.

关键词： 1D TOCSY NMR technologies Xylenes Aromatic compounds Structure information of entire molecular Qualitative analysis

Ultrathin two-dimensional medium-entropy oxide as a highly efficient and stable electrocatalyst for oxygen evolution reaction

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nano Research 2024年第4期17卷 2555-2562页

作者： Guangyuan yan Tianlu Wang Biwei zhao Wenjing Gao Tong Wu Liming Ou School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

Medium-entropy oxides(MEOs)with broad compositional tunability and entropy-driven structural stability,are receiving booming attention as a promising candidate for oxygen evolution reaction(OER)***,ultrathin two-dimensional(2D)nanostructure offers extremely large specific surface area and is therefore considered to be an ideal catalyst ***,it remains a grant challenge to synthesize ultrathin 2D MEOs due to distinct nucleation and growth kinetics of constituent multimetallic elements in 2D anisotropic *** this work,an ultrathin 2D MEO(MnFeCoNi)O was successfully synthesized by a facile and low-temperature ionic layer epitaxy *** from multi-metal synergistic effects within ultrathin 2D nanostructure,this 2D MEO(MnFeCoNi)O revealed excellent OER electrocatalytic performance with a quite low overpotential of 117 mV at 10 mA·cm^(-2) and an impressive stability for 120 h continuous operation with only 6.9%***,the extremely high mass activity(5584.3 A·g^(-1))was three orders of magnitude higher than benchmark RuO_(2)(3.4 A·g^(-1))at the same overpotential of 117 *** work opens up a new avenue for developing highly efficient and stable electrocatalysts by creating 2D nanostructured MEOs.

关键词： medium-entropy oxide two-dimensional nanomaterials ionic layer epitaxy oxygen evolution reaction electrocatalysis

Influence and optimization of swirler parameters on elbow wear of deep coal fluidization pipeline transportation system

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Friction 2024年第7期12卷 1408-1433页

作者： Shaodi zhao Jiusheng BAO Shirong GE Zhongbin WANG yan YIN Congguang HUANG School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanical Electronic and Information Engineering China University of Mining and Technology-BeijingBeijing 100083China Frontier Scientific Research Center for Fluided Mining of Deep Underground Resources China University of Mining and TechnologyXuzhou 221008China

Elbow wear is a major threat to the multiphase pipeline transportation industry,which has a negative impact on the stable operation of the transportation *** order to find the wear reduction methods of elbows in the fluidization pipeline transportation system for 2000-meter-deep coal resources,the swirler was installed upstream of the elbows,and wear simulations and tests of three kinds of elbows were carried *** results showed that the maximum wear rate(MWR)of elbows increased and then decreased along the elbow *** to the different directions of gravity,the heavy wear position(HWP)of the horizontal-vertical(H-V)elbow was in front of the vertical-horizontal(V-H)*** the downstream portion of the horizontal-horizontal(H-H)elbow was still a horizontal pipe,the HWP of the H-H elbow almost covered the whole *** swirler placed upstream of the elbows could make the particles at the elbow move to the intrados of the elbows,resulting in less collision between the particles and the extrados of the elbows,thus reducing the wear of the *** wear reduction effects of swirlers on three different elbows were favorably connected with the guide vane angle(GVA)and negatively correlated with the guide vane length(GVL),decreased first and then increased as the guide vane height(GVH)increased,and were little affected by the guide vane number(GVN)and the guide vane thickness(GVT).The mathematical models between the MWR of the elbows and guide vane parameters were *** bench tests,the wear reduction effect of three kinds of elbows under the optimal guide vane parameters was 58.4%,76.9%,and 78.6%,*** errors between the bench test results and the simulation results were around 10%.

关键词： pipe elbow erosion wear spiral flow swirler guide vane parameters particle collision

Synergistic enhancement of Ce-ZnO/g-C_(3)N_(4)photocatalytic performance using N,O-bis-vacancy induction and S-scheme heterojunctions

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Journal of Rare Earths 2024年第5期42卷 817-826,I0001页

作者： Guyu Zhang Yuan Zhang Xinlei zhao Yujiang Jiao Yumin yan Jianhui Jiang Engineering Laboratory of Chemical Resources Utilization in South Xinjiang of Xinjiang Production and Construction Corps College of Chemistry a Chemical EngineeringTarimUniversityAlar843300China

The photocatalytic decontamination of organic pollutants is an environmentally friendly and efficient water treatment *** introduction of vacancies,heterojunctions,and doping can enhance the performance of photocatalysts for such *** this study,N,O double-vacancy Ce-ZnO/g-C_(3)N_(4)S-scheme heterojunction photocatalysts were prepared,It is found that the electron separation and transfer efficiencies are considerably improved by the presence of nitrogen vacancies in graphitic ca rbon nitride(g-C_(3)N_(4))and oxygen vacancies in ZnO,in addition to the S-scheme heterojunction created between the two *** the degradation of methylene blue and ciprofloxacin,the degradation rates exhibited by Ce-ZnO/g-C_(3)N_(4)are significantly higher than those of the g=C_(3)N_(4)/ZnO *** remarkable photocatalytic performance of Ce-ZnO/g-C_(3)N_(4)may result from three key factors;(ⅰ)Ce doping,which produces impurity energy levels;(ⅱ)the generation of electron capture centres by the N and O vacancies;and(ⅲ)the synergistic effect of the S-type heterojunction formed at the interface between the two materials,This study therefore provides new approaches for the use of doping,vacancies,and heterojunctions to induce the efficient degradation of organic pollutants.

关键词： Photocatalysis Vacancy S-scheme Ce-ZnO/g-C_(3)N_(4) Degradation Rare earths

Hydrogel-Assisted Electrokinetics for High-Resolution and Non-invasive Flow Monitoring in Microfluidic Chips

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Chinese Journal of Chemistry 2024年第6期42卷 571-577页

作者： na zhao yanni Ma Zehua Yu Jun Huang Xiangqian Fu Tao Qiu Kang Liu MOE Key Laboratory of Hydraulic Machinery Transients School of Power and Mechanical EngineeringWuhan UniversityWuhanHubei430072 China Department of Urology Renmin Hospital of Wuhan UniversityWuhanHubei430072 China Department of Organ Transplantation Renmin Hospital of Wuhan UniversityWuhanHubei430072 China

Convenient non-invasive flow monitoring would facilitate the operation and control in microfluidic chips,but is challenging due to the small space of microchannels and complex operation required in traditional optical *** this work,we propose a novel non-invasive strategy to probe microfluidic flows via streaming potential *** sealing one side of the microchannel with a piece of hydrogel film,streaming potential inside the channel can be clearly detected by electrodes at outer surface of the hydrogel due to ion diffusion in the *** is detected without sensors contacting with the internal ***,the electrodes shape like a tiny probe,which can move around mapping the flow distribution in a chip with the spatial resolution of 1 mm and flow rate detection limit of 3μL·min–*** inside the channels can also be detected,due to the fluctuation of streaming voltage when gas-liquid interface flows through the electrode,showing an easy and potential way for multi-functional flow monitoring in microfluidic chips.

关键词： Microfluidics Hydrogels Electrokinetics Flow monitoring Non-invasive Sensor Charge transport

Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： zhao Tao SHI yan LU Kun XI Xiang WU XueZhong XIAO DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

The guest CH_(3)CN molecule triggers solid-state photochromism in a Cu_(2)I_(2)-based MOF for advanced time-dependent encryption and inkless erasable printing

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Chinese Chemical Letters 2024年第3期35卷 532-537页

作者： Meng-Juan Wang Bo Li Yong-Li Wei Shu-na zhao Shuang-Quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

It remains a big challenge to develop solid-state stimuli-responsive materials for time-dependent information encryption and inkless erasable printing with long retention ***,a 2D Cu_(2)I_(2)-based MOF with photoresponsive spiropyran(SP)groups orderly installed on its skeleton is *** structural isomerization from SP to colored merocyanine(MC)form can be triggered by removing the CH_(3)CN ***,the degree of structural isomerization and the retention time can be adjusted by controlling the amount of CH_(3)CN guests,exhibiting dynamic photochromic behavior with multicolor states and tunable retention *** on these advantages,time-dependent information encryption is successfully ***,the long retention time(>72 h)of the MC form under daylight conditions in the CH_(3)CN-removed Cu_(2)I_(2)-based MOF and good repeatability make it promising in various applications,such as temporary calendars,price-cards,billboards,and reusable identity *** work provides a novel design strategy to fabricate multi-functional MOF-based smart materials for challenging applications of time-dependent information encryption and inkless erasable printing.

关键词： Stimuli-responsive materials Spiropyran Solid-state photochromism Time-dependent encryption Inkless erasable printing

Discovery of GluN2A subtype-selective N-methyl-d-aspartate(NMDA)receptor ligands

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1987-2005页

作者： Liyang Jiang na Liu Fabao zhao Boshi Huang Dongwei Kang Peng Zhan Xinyong Liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China

The N-methyl-d-aspartate(NMDA)receptors,which belong to the ionotropic Glutamate receptors,constitute a family of ligand-gated ion *** the various subtypes of NMDA receptors,the GluN1/2A subtype plays a significant role in central nervous system(CNS)*** present article aims to provide a comprehensive review of ligands targeting GluN2A-containing NMDA receptors,encompassing negative allosteric modulators(naMs),positive allosteric modulators(PAMs)and competitive ***,the ligands’structure–activity relationships(SARs)and the binding models of representative ligands are also discussed,providing valuable insights for the clinical rational design of effective drugs targeting CNS diseases.

关键词： NMDA receptors GluN2A subtype Subtype-selective ligands SARs Protein ligand interactions