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Ru(II)-Catalyzed ortho C-H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

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Chinese Journal of Chemistry 2024年第9期42卷 985-989页

作者： jing Zhang Quan-Jian Luo han-Chi Wang Jin-heng Li Bo Sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology QingdaoShandong266042China State key Laboratory of Applied Organic Chemistry Lanzhou University LanzhouGansu 7300ooChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been *** reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high *** addition,the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates,highlighting the practicality of this strategy for synthesis.

关键词： Ru(II) Allylation N-Aryl-7-azaindoles Cyclic carbonates Heterocyclic compounds C-H activation

A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 215-228页

作者： Shuyong Duan Jialin Zhang heng Ouyang Xu han Guirong Liu State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300401China Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnati 45221USA

On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material *** work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material *** use of echo groups allows the use of lower frequencies,and hence more accommodative to structural *** train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given *** waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical *** results in a set of dataset for training the ANN *** the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the *** tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed *** results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic ***,the reliability and accuracy of inverse prediction is significantly ***,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment.

关键词： Parameter identification Ultrasonic echo group High-precision modeling Artificial neural network NDT

Thermodynamic and experimental study of high-temperature roasting of blast furnace gas ash for recovery of metallic zinc and iron

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Journal of Iron and Steel Research International 2024年第1期31卷 108-120页

作者： Zi-han Wang jing Guo han-jie Guo Bin Li School of Metallurgical Engineering University of Science and Technology BeijingBeijing100083China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina

A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free *** results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron *** the full temperature range,iron oxides were more easily reduced than zinc *** of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of *** the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction *** the C/O ratio increased,the metallization and dezincification rates first increased and then *** effect of reduction time on BFA reduction was similar to that of reaction temperature.

关键词： Blast furnace gas ash Thermodynamics Zinc removal Iron reduction High-temperature reduction roasting Integrated utilization

High-capacity potassium ion storage mechanisms in a soft carbon revealed by solid-state NMR spectroscopy

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Rare Metals 2022年第11期41卷 3752-3761页

作者： jing-heng han Jia He Qi-Yao Zou Jie Zhang Zhi Yang Zhi-Wei Zhao Hui-Xin Chen Hong-Jun Yue Da-Wei Wang Hai-Chen Lin Hao-Dong Liu Gui-Ming Zhong Zhang-Quan Peng College of Chemistry and Material Science Fujian Normal UniversityFuzhou350000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare-Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen361021China Laboratory of Advanced Spectro-Electrochemistry and Li-Ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Jilin UniversityChangchun130025China Chemical Engineering University of California San DiegoLa JollaSan DiegoCA92093USA

Carbon materials are crucially important for the realization of potassium-ion ***,the potassium storage mechanisms in various carbon materials are incompletely ***,solid-state ^(13)C nuclear magnetic resonance(NMR) spectroscopy coupled with Raman and X-ray diffraction(XRD) techniques are employed to study the reaction mechanism in a soft carbon *** is revealed that the insertion of potassium ions into the soft carbon firstly induces a transformation of the disordered region to short-range ordered stacking,involving both the pristine local unorganized and organized carbon ***,potassium ions intercalate into the rearranged carbon structure,finally producing the nano-sized KC_(8).Moreover,a remarkable c apacity of 322 mAh·g^(-1) with a low mid potassiation voltage of <0.3 V is present for the prepared soft carbon,which is on account of the underlying potassium storage sites,including the disordered stacking carbon as a main component of the soft *** results suggest that regulating the disordered stacking region in the turbostratic structure of soft carbon is a critical issue for further improving the potassium storage performance.

关键词： Reaction mechanism Soft carbon Solid-state nuclear magnetic resonance(NMR) Anode Potassium-ion batteries(PIBs)

Nonlinear Registration of Brain Magnetic Resonance Images with Cross Constraints of Intensity and Structure

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Computers, Materials & Continua 2024年第5期79卷 2295-2313页

作者： han Zhou HongtaoXu Xinyue Chang Wei Zhang heng Dong Digital Fujian Research Institute of Big Data forAgriculture and Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China College of Computer and Information Science Fujian Agriculture and Forestry UniversityFuzhou350002China

Many deep learning-based registration methods rely on a single-stream encoder-decoder network for computing deformation fields between 3D ***,these methods often lack constraint information and overlook semantic consistency,limiting their *** address these issues,we present a novel approach for medical image registration called theDual-VoxelMorph,featuring a dual-channel cross-constraint *** innovative network utilizes both intensity and segmentation images,which share identical semantic information and feature *** encoder-decoder structures calculate deformation fields for intensity and segmentation images,as generated by the dual-channel cross-constraint *** design facilitates bidirectional communication between grayscale and segmentation information,enabling the model to better learn the corresponding grayscale and segmentation details of the same anatomical *** ensure semantic and directional consistency,we introduce constraints and apply the cosine similarity function to enhance semantic *** on four public datasets demonstrates superior performance compared to the baselinemethod,achieving Dice scores of 79.9%,64.5%,69.9%,and 63.5%for OASIS-1,OASIS-3,LPBA40,and ADNI,respectively.

关键词： Medical image registration cross constraint semantic consistency directional consistency dual-channel

A Simple Proof of ACC for Minimal Log Discrepancies for Surfaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 425-434页

作者： jing Jun han Yu Jie LUO Shanghai Center for Mathematical Sciences Fudan UniversityJiangwan CampusShanghai 200438P.R.China Department of Mathematics Johns Hopkins UniversityBaltimoreMD 21218USA

Following Shokurov's idea,we give a simple proof of the ACC conjecture for minimal log discrepancies for surfaces.

关键词： Ascending chain condition minimal log discrepancies minimal model program surface

Experimental and numerical study on dynamic mechanical behaviors of shale under true triaxial compression at high strain rate

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International Journal of Mining Science and Technology 2024年第2期34卷 149-165页

作者： Xiaoping Zhou Linyuan han jing Bi Yundong Shou School of Civil Engineering Wuhan UniversityWuhan 430072China College of Civil Engineering Guizhou UniversityGuiyang 550025China

High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing *** effectively extract shale gas,it is important to understand the dynamic mechanical properties of *** experiments on shale subjected to true triaxial compression at different strain rates are first conducted in this *** dynamic stress-strain curves,peak strain,peak stress and failure modes of shale are *** results of the study indicate that the intermediate principal stress and the minor principal stress have the significant influence on the dynamic mechanical behaviors,although this effect decreases as the strain rate *** characteristics of compression-shear failure primarily occur in shale subjected to triaxial compression at high strain rates,which distinguishes it from the fragmentation characteristics observed in shale under dynamic uniaxial ***,a numerical three-dimensional Split Hopkinson Pressure Bar(3D-SHPB),which is established by coupling PFC3D and FLAC3D methods,is validated to replicate the laboratory characteristics of *** dynamic mechanical characteristics of shale subjected to different confining stresses are systematically investigated by the coupling PFC3D and FLAC3D *** numerical results are in good agreement with the experimental data.

关键词： Dynamic behaviors True triaxial compression High strain rates Dynamic failure mechanism PFC3D-FLAC3D coupled method

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

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Nuclear Science and Techniques 2024年第4期35卷 29-45页

作者： han Yin Xiao-jing Liu Teng-Fei Zhang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 2002040China

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport ***,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational *** paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface *** algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without *** the formation tasks are completed,a collective operation merges and shares the matrix sets among the *** the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix ***-to-point communication is conducted between adjacent subdomains to exchange data along the *** accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test *** results obtained with multiple processors agree well with those obtained from Monte Carlo *** parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 *** addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

关键词： Neutron transport Variational nodal method Parallelization KAIST JRR-3

Mastering air combat game with deep reinforcement learning

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Defence Technology（防务技术） 2024年第4期34卷 295-312页

作者： jingyu Zhu Minchi Kuang Wenqing Zhou heng Shi Jihong Zhu Xu han Department of Precision Instruments Tsinghua UniversityBeijing 100084China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Chengdu Aircraft Design&Research Institute Aviation Industry Corporation of ChinaChengdu 610000China

Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural *** loss is the difficulty of learning new knowledge after the network has *** this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning *** motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a ***,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be *** addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an *** the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions *** the interruption mechanism can significantly improve the performance of the *** simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data *** experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper.

关键词： Air combat MCLDPPO Interruption mechanism Digital twin Distributed system