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A　FACILE　SYNTHESIS　OF　AZACROWN　ETHERS　WITH　INTRAANNULAR　PHENOLIC　GROUPS　IN　A　TWO－PHASE　SYSTEM

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Chinese Chemical Letters 1996年第3期7卷 211-212页

作者： Guo Ping XUE cheng tai wu(Department of Chemistry, wuhan University,wuhan 430072) wuHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

Azacrown ethers with intraannutal phenolic grouch are readily prepared by thereaction of 1, 8- bis (P-tolylsulphonybono) -3, 6-dioxaoctane with 2, 6-bis (bromomethyl) -4-R-anisole (R=CH3, Cl, Br) in a two-phase system...

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Synthesis of Two New Types of N-Phenyl and N,N'-Diphenyl Azathiacrown Ether Analogs

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Chinese Chemical Letters 1998年第1期9卷 17-20页

作者： Chang Rong NIU Hua JIANG and cheng tai wu (Department of Chemistry, wuhan University, wuhan 430072) wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Two types of N-phenyl and N,N-diphenyl azathiacrown ether analogs, Which contain two sulfur atoms, one or two oxygen atoms. and one or two nitrogen atoms, were synthesized by the reaction of an appropriate halide with... 详细信息

关键词： Azathiacrown Ether Analog,α,ω-dithiol

Synthesis of New β-Cyclodextrin Dimers Bridged by Schiff Base

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Chinese Chemical Letters 1998年第7期9卷 609-610页

作者： Yong LIU Guo Ping XUE cheng tai wu (Department of Chemistry wuhan University, wuhan 430072) wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Four β-cyclodextrin dimers bearing the Schiff base bridge on their primary faces have been synthesized.

关键词： cyclodextrin dimer Schiff base

Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring

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Chinese Chemical Letters 1997年第7期8卷 569-572页

作者： Chang Rong NIU Hai Ning ZHANG cheng tai wu(Department of Chemistry, wuhan University, wuhan 430072) wuHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines. The chemical structures of the new compounds were characterized by elemental analysis, infrared spectra, nuclear magnetic resonance spectra and mass spectrometry.

关键词： OCH IR cm KBr HNMR Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring

SYNTHESIS OF AZA-OXA MACROCYCLES CONtaiNING PYRIDINE RING

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Chinese Chemical Letters 1994年第1期5卷 19-22页

作者： Guo Ping XUE cheng tai wu(Department of Chemistry, wuhan University. wuhan 430072)

A new type of aza-oxa macrocycles containing pyridine ring which may be used for binding of prinary ammonium cations(R-NH) were prepared from 2.6-di(bromomethyl) pyridine and appropriate diol.

关键词： OXA SYNTHESIS OF AZA-OXA MACROCYCLES CONtaiNING PYRIDINE RING

SYNTHESIS OF NEW DIAZA-CROWN ETHERS WITH INWARD-FACING PHENOLIC GROUPS

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Chinese Chemical Letters 1994年第5期5卷 365-366页

作者： Guo Ping XUE Han Sheng XU and cheng tai wu (Department of Chemistry, Northwest Normal University, wuhan 430072)

New diaza-crown ethers with inward-facing phenolic groups were synthesized from 2,6- his (bromQmethyl ) -- 4 -- R--aniSOle (R -- CH 3, CI ) and 3, 9 -- ditOSyl-- 6 -- oxa.-- 3, 9 --diaZaufldecane-- l,1 1-diul.

关键词：

A　MODIFICATION　OF　THE　SYNTHESIS　OF　MACROCYCLIC　POLYAMINES　CONtaiNING　PYRIDINE　RING

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Chinese Chemical Letters 1994年第1期5卷 23-24页

作者： Guo Ping XUE Yong Bing HE cheng tai wu (Department of Chemistry.wuhan University, wuhan. 430072)

A convenient procedure was developed for the synthesis of macrocyclic polyamines containing pyridine ring by direct condensation of 2,6-di(bromomethyl) pyridine with N-tosyl polyethylene polyamines in DMF in the prese...

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A CONVENIENT SYNTHESIS OF NEW HYDROXYL CYCLIC AZA COMPOUNDS

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Chinese Chemical Letters 1994年第6期5卷 457-458页

作者： Guo Ping XUE Sheng Hua LIU En Qin FU Han Sheng XU and cheng tai wu (Department of Chemistry, wuhan University, wuhan 430072)

A convenient synthetic route to a series of hydroxyl cyclic di- and tri-aza compounds was described. Condensation of 1, 3-dichloropropanol[2] with the appropriate disodium salts of N-tosylated di-and triamine in EtOH gave the corresponding 7-, 8- and 10-membered di- and triamine cycles in reasonable yields. The tosyl groups were removed with 33%HBr-HOAc in ca.90% yields.

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A Hybrid Approach for Pavement Crack Detection Using Mask R-CNN and Vision Transformer Model

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Computers, Materials & Continua 2025年第1期82卷 561-577页

作者： Shorouq Alshawabkeh Li wu Daojun Dong Yao cheng Liping Li Faculty of Engineering China University of GeosciencesWuhan430074China

Detecting pavement cracks is critical for road safety and infrastructure *** methods,relying on manual inspection and basic image processing,are time-consuming and prone to *** deep-learning(DL)methods automate crack detection,but many still struggle with variable crack patterns and environmental *** study aims to address these limitations by introducing the Masker Transformer,a novel hybrid deep learning model that integrates the precise localization capabilities of Mask Region-based Convolutional Neural Network(Mask R-CNN)with the global contextual awareness of Vision Transformer(ViT).The research focuses on leveraging the strengths of both architectures to enhance segmentation accuracy and adaptability across different pavement *** evaluated the performance of theMaskerTransformer against other state-of-theartmodels such asU-Net,TransformerU-Net(TransUNet),U-NetTransformer(UNETr),SwinU-NetTransformer(Swin-UNETr),You Only Look Once version 8(YoloV8),and Mask R-CNN using two benchmark datasets:Crack500 and *** findings reveal that the MaskerTransformer significantly outperforms the existing models,achieving the highest Dice SimilarityCoefficient(DSC),precision,recall,and F1-Score across both ***,the model attained a DSC of 80.04%on Crack500 and 91.37%on DeepCrack,demonstrating superior segmentation accuracy and *** high precision and recall rates further substantiate its effectiveness in real-world applications,suggesting that the Masker Transformer can serve as a robust tool for automated pavement crack detection,potentially replacing more traditional methods.

关键词： Pavement crack segmentation transportation deep learning vision transformer Mask R-CNN image segmentation