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Synthesis and Crystal Structure of 4-Azido-2,2,6,6-Tetramethylpiperidine-1-oxyl Free Radical

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Chinese Journal of Structural Chemistry 2006年第2期25卷 127-130页

作者： ZHOU bao-han CHEN yun-Feng YIN Guo-Dong WU An-Xin Key Laboratory of Pesticide and Chemical Biology Ministry of Education College of Chemistry Central China Normal University Wuhan 430079 China

The title compound 4-azido-2,2,6,6-tetramethylpiperidine-l-oxyl （C9H17N4O, Mr = 197.27） has been synthesized and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1^- with a = 5.8464（12）, b = 8.2476（17）, c = 11.954（2） A°, a = 101.973（4）, β = 97.186（3）, γ, = 100.232（3）°, V = 546.98（19） ,A°^3, Z = 2, Dc= 1.198 g/cm^3, μ（MoKa） = 0.082 mm^-1, F（000） = 214, R = 0.0495 and wR = 0.1355 for 1677 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the six-membered ring adopts a chair conformation and the bond length of N（1）-O（1） is 1.2838（19）A°.

关键词： crystal structure nitroxide radical synthesis

A CAD System for Tube Drawing Based on Finite Element Simulation of Drawing Process

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Journal of Iron and Steel Research International 2001年第1期8卷 27-33页

作者： han bao-yun JIN Ming WU You-cai ZHONG Qian-xia Central Iron & Steel Research Institute

Acicular Ferrite (AF) is beneficial in welds because it provides a tough and strong microstructure. Therefore, much works have been done in the study of the effect of alloying elements and welding conditions aimed at obtaining more AF in the weld metal. However, the knowledge about the nature of AF is limited due to the lack of kinetics researches. In this paper, the kinetic curves of AF transformation in an X65 weld metal were established by means of welding thermal simulation test. The results showed that AF transformation is a typical diffusion process of nucleation and growth with incubation period. AF transformation in weld metal obeys the relationship described by JMA Equation. The effect of welding heat input was also studied.

关键词： weld metal acicular ferrite kinetics pipe steel

Unveiling oscillatory nature for sustainable fuel production

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National Science Review 2024年第05期11卷 90-91页

作者： Ning han Ye Wang bao-Lian Su Department of Materials Engineering State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters College of Chemistry and Chemical Engineering Xiamen University Laboratory of Inorganic Materials Chemistry(CMI) University of Namur State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

A century ago, in 1923, Franz Fischer and hans Tropsch introduced the groundbreaking Fischer–Tropsch (FT) synthesis, a heterogeneous catalytic process used to convert synthesis gas (syngas,CO+H2) into multi-carbon hydrocarbons [1]. Over the past 100 years, FT synthesis has emerged as a pivotal method for converting non-petroleum resources into exceptionally clean fuels or valuable chemicals via syngas [2–4].

关键词： CO HYDROGENATION CATALYSTS BEHAVIOR KINETICS

Hybrid tri-memristor hyperchaotic map and application in Wasserstein Generative Adversarial Nets

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Science China(Technological Sciences) 2024年第6期67卷 1855-1865页

作者： GU Yang bao han YU XiHong HUA Zhongyun bao BoCheng XU Quan School of Microelectronics and Control Engineering Changzhou UniversityChangzhou213159China School of Computer Science and Technology Harbin Institute of TechnologyShenzhen518055China

Inspired by basic circuit connection methods,memristors can also be utilized in the construction of complex discrete chaotic *** investigate the dynamical effects of hybrid memristors,we propose two hybrid tri-memristor hyperchaotic(HTMH)mapping structures based on the hybrid parallel/cascade and cascade/parallel operations,*** the HTMH mapping structure with hybrid parallel/cascade operation as an example,this map possesses a spatial invariant set whose stability is closely related to the initial states of the *** distributions and bifurcation behaviours dependent on the control parameters are explored with numerical ***,the memristor initial offset-boosting mechanism is theoretically demonstrated,and memristor initial offset-boosting behaviours are numerically *** results clarify that the HTMH map can exhibit hyperchaotic behaviours and extreme multistability with homogeneous coexisting infinite *** addition,an FPGA hardware platform is fabricated to implement the HTMH map and generate pseudorandom numbers(PRNs)with high ***,the generated PRNs can be applied in Wasserstein generative adversarial nets(WGANs)to enhance training stability and generation capability.

关键词： memristor hybrid tri-memristor map spatial invariant set hyperchaos extreme multistability generative adversarial nets

Fabrication of a 25.2 T NMR magnet for an extreme condition user facility in China

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National Science Review 2024年第7期11卷 62-64页

作者： Hui han yun Shang MRI Research Institute Department of RadiologyWeill Medical College of Cornell University

An ultra-high field magnet（>20 T）is desirable for studying the characteristics of new materials under extreme magnetic conditions [1]. Additionally,such field strength will result in resonance frequencies close to or greater than 1 GHz when applied to the study of1H signals from biomolecules by nuclear magnetic resonance（NMR）,which will lead to a higher signal-to-noise ratio, better sensitivity and a higher spectral resolution due to increased chemical shift dispersion [2].

关键词： NMR double pancake high temperature superconducting magnet ultra-high field

Temperature-controlled DCP Fluorescent Probe Based on Hydrogel-immobilized Quantum Dots Composite

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 931-936页

作者：童伊琳杨坤 han Xuecai YU Kan bao Jiaqi Faculty Information Science and Technology Wenhua CollegeWuhan 430074China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430074China Yangtze Optical Fibre and Cable Joint Stock Limited Company Wuhan 430074China

A composite was created by incorporating the quantum dot-enhanced SiO_(2)nanoparticles within this *** on this composite,a temperature-controlled fluorescent probe for DCP was developed.A meticulous examination of this probe revealed its attributes and factors affecting its *** using temperature modulation,the probe was adept at detecting DCP concentrations ranging between 1.0×10^(-6)and 9.0×10^(-6)mol/*** a probe offers remarkable selectivity,repeatability,and robust stability,so that the detection of DCP can be carried out at different temperatures,and a fast,reliable,sensitive and low-cost intelligent detection method is realized.

关键词： temperature-controlled fluorescent probe hydrogel-immobilized quantum dots composite DCP

Topology of charged AdS black hole in restricted phase space

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Chinese Physics C 2024年第9期48卷 291-299页

作者： han Wang yun-Zhi Du College of Mathematics and Statistics Shanxi Datong UniversityDatong 037009China Department of Physics Shanxi Datong UniversityDatong 037009China Institute of Theoretical Physics Shanxi Datong UniversityDatong 037009China

The local topological properties of black hole systems can be expressed through winding numbers as *** date,AdS black hole thermodynamics are often depicted by the dual parameters of(T,S),(P,V),(Φ,Q) in the extended phase space,while there have been several studies on the black hole thermodynamics in the restricted phase *** this paper,we analyze the topological properties of charged AdS black holes in the restricted phase space under the higher-dimension and higher-order curvature gravity *** results show that the topological number of the charged black hole in the same canonical ensembles is a constant and is independent of the concrete dual thermodynamical ***,the topological number in the grand canonical ensemble is different from that in the canonical ensemble for the same black hole ***,these results are independent of dimension d and highe st order k of the Lanczos-Lovelock densities.

关键词： topology phase transition black hole

Construction of flower-like MoS_(2)decorated on Cu doped CoZn-ZIF derived N-doped carbon as superior microwave absorber

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Nano Research 2024年第9期17卷 8250-8260页

作者： yun han Di Lan Mengjun han Zihao Xia Jiaxiao Zou Zirui Jia College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China

The rational design of composition nanostructures and morphologies of the carbon-based composites materials has a significant potential for tuning electromagnetic parameters and thereby improving their performance as electromagnetic wave(EMW)*** this work,the flower-like Cu/Co-NC/MoS_(2)(NC=N-doped carbon skeleton)composites were successfully prepared by employing CuCoZn-ZIF(ZIF=zeolitic imidazolate framework)as precursor with subsequent annealing and hydrothermal *** unique flower-like morphology and electromagnetic synergy strategy between components enable the as-obtained Cu/Co-NC/MoS_(2)composites to exhibit outstanding microwave absorption ***,the minimum reflection loss of Cu/Co-NC/MoS_(2)reaches-54.36 dB at 2.7 *** the thickness reduces to 2.2 mm,the maximum effective absorption bandwidth can be achieved as large as 6.72 *** research develops useful ideas for optimizing multicomponent microwave absorbing materials.

关键词： ternary metal-organic frameworks(MOFs) MoS_(2) flower-like morphology microwave absorption

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua Gong Quan Li han-sheng bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation