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A novel solid state Michael addition reaction of N-heterocyclic compounds containing active C-H bond

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Chinese Journal of Chemistry 1996年第5期14卷 421-427页

作者： Li, XL Wang, YM tian, b Meng, Jb NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

In this paper, a novel solid state Michael-type addition reaction of N-heterocyclic compounds containing the active-CH group was investigated. 3-Methyl-1-phenyl-5-pyrazolone (MPP) and indole (In) reacted with 4-arylmethylene-3-methyl-1-phenyl-5-pyrazolone (1) in the solid state at room temperature to give the corresponding adducts, aryl-4,4'-bis(5-hydroxy-3-methyl-1-phenyl-pyrazolyl) methane (2a-n) and 1-aryl-1-(5'-hydroxy-3'-methyl-1'-phenyl-4'-pyrazolyl)-1-(3 ''-indolyl) methane (3a-n), respectively. This is a feasible method for preparing the compound which contains two heterocyclic groups on the same carbon.

关键词： indole pyrazolone Michael addition solid state reaction

From Receptor-Like Kinases to Calcium Spikes： What Are the Missing Links？

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Molecular Plant 2014年第10期7卷 1501-1504页

作者： Feng Yu[a],, Wang tian[b], Sheng Luan[b],[c], a Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan University Changsha 410082 P.R. Chinab Department of Plant and Microbial Biology University of California Berkeley CA 94720 USAc NJU-NJFU Joint Institute for Plant Molecular Biology School of Life Sciences Nanjing University Nanjing 210093 P.R. China

As sessile organisms, plants have evolved with complex signaling networks to cope with the constantly changing environment. Receptor-like kinases （RLKs） and calcium both play important roles during the early stage of envi- ronmental responses in plants. RLKs are trans-membrane receptor kinases that sense extracellular signals, such as hormones, peptides, and pathogens, and trigger sig- nal transduction pathways leading to cellular responses （Osakabe et al., 2013）.

关键词： ARAbIDOPSIS PERCEPTION ATPEPR1

Synthesis of new heterocycles 1,3,2,6-dioxaphosphaselenacyclooctanes

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Chinese Journal of Chemistry 1997年第5期15卷 450-458页

作者： Li, JL tian, b Zhao, CQ Wang, YM Meng, Jb Wang, HG Nankai Univ Dept Chem Tianjin 300071 Peoples R China Nankai Univ Cent Lab Tianjin 300071 Peoples R China

New phosphorus-and selenium containing heterocyclyes, 1,3,2,6-dioxaphosphaselena-cyclooctanes (1a-1h), were synthesized by the reaction of bis(2-hydroxyethyl)selenide with RP(X)Cl-2 where R=alkoxyl, aroxyl, aryl. and X=O or lone pair. Their structures were determined by spectroscopies and elemental analyses and finally confirmed by the X-ray crystallographic analysis of 1c. The molecular structures of the heterocycles were discussed in term of conformational analysis.

关键词： heterocycles synthesis structure

Preparation and characterization of nanostructured Al_2O_3-13wt.%TiO_2 ceramic coatings by plasma spraying

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Rare Metals 2009年第5期28卷 465-470页

作者： WANG Dongsheng tian Zongjun SHEN Lida LIU Zhidong HUANG Yinhui Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Nanostructured and conventional Al2O3-13wt.%TiO2 ceramic coatings were prepared by plasma spraying with nanostructured agglomerated and conventional powders, respectively. The microstructure and microhardness of the coatings were investigated using scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and microhardness measurement. Meanwhile, the friction and wear behaviors were analyzed and compared using a ball-on-disk tribometer. The results show that the conventional coating has lamellar stacking characteristic and has some pores. However, the nanostructured coating shows a bimodal microstructure, which is composed of both fully melted regions and partially melted regions. According to the microstructural difference, the partially melted regions can be divided into liquid-phase sintered regions （a three-dimensional net or skeleton-like structure： Al2O3-rich submicron particles embedded in the TiO2-rich matrix） and solid-phase sintered regions （remained nanoparticles）. The microstructural characteristics of the liquid-phase sintered region are formed due to the selective melting of TiO2 nanoparticles during plasma spraying. On the other hand, the TiO2 and Al2O3 nanoparticles of the solid-phase sintered regions are all unmelted during plasma spraying. Due to the existence of nanostructured microstructures, the nanostructured coating has a higher microhardness, a lower friction coefficient, and a better wear resistance than the conventional coating.

关键词： surface coating nanostructured coating plasma spraying microstructure microhardness wear resistance

Capacitance of High-Voltage Coaxial Cable in Plasma Immersion Ion Implantation

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Journal of Materials Science & Technology 2001年第1期17卷 41-42页

作者： X.b.tian L.P.Wang D.T.K.Kwok b.Y Tang P.K.Chu Department of Physics&Materials Science City University of Hong KongHong KongChina

Plasma immersion ion implantation (PIII) is an excellent technique for the surf see modification of complex-shaped components. Owing to pulsed operation mode of the high voltage and large slew rate, the capacitance on the high-voltage coaxial cable can be detrimental to the process and cannot be ignored. In fact, a significant portion of the rise-time/fall-time of the implantation voltage pulse and big initial current can be attributed to the coaxial cable.

关键词： surface modification ion implantation high voltage mode of

Electrochemical characteristics of ternary and quadruple lithium silicon nitrides as anode material for lithium ion batteries:the influence of precursors

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Rare Metals 2008年第2期27卷 170-174页

作者： WEN Zhongsheng tian Feng SUN Juncai JI Shijun XIE Jingying Institute of Materials and Technology Dalian Maritime University Dalian 116026 China Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Ternary and quadruple lithium silicon nitride anode materials for lithium ion batteries with different precursors were prepared by the simple process of high-energy ball milling. High capacity and excellent cyclability were obtained. The influence of precursor introduction on the electrochemical performance of products was investigated. This research reveals that the electrochemical performance of lithium silicon hitilde can be enhanced significantly by doping O. The cyclability of quadruple lithium silicon nitfide can be optimized remarkably by controlling the introduction quantity of the precursors. It is possible for the composite to be used as a capacity compensator within a wide voltage cut-off window.

关键词： lithium ion batteries high-capacity electrode material high-energy ball milling lithium silicon nitride wide voltage cut-off window

A blockchain-based Access Control Scheme for Reputation Value Attributes of the Internet of Things

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Computers, Materials & Continua 2024年第1期78卷 1297-1310页

作者： Hongliang tian Junyuan tian College of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data *** address these issues,a blockchain-based IoT reputation value attribute access control scheme is ***,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control *** simulation experiments based on the Hyperledger Fabric *** simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices.

关键词： blockchain IoT access control Hyperledger Fabric

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Transformer and GAN-based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis *** this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture ***,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model *** comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)