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Catalytic diastereoselective and enantioconvergent C(sp^3)–C(sp^3) cross-coupling of racemic partners

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Science China Chemistry 2020年第7期63卷 871-872页

作者： Ai-E Wang pei-Qiang huang Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Carbon-carbon bond formation is the core of organic *** metal-catalyzed cross-coupling reaction between organohalides and organometallic reagents is one of the most important and straightforward methods for construction of C-C *** catalytic cross coupling between two sp^2-carbon centers,e.g.,aryl-aryl crosscouplings,has become a routine transformation in laboratories and industrial processes for synthesis of drugs and fine ***-catalyzed cross-coupling between two sp'-carbon centers(Figure 1(a)).

关键词： synthesis. coupling centers

Overview of Computational Modeling in Nano/Micro Scaled Thin Films Mechanical Properties and Its Applications

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Computer Modeling in Engineering & Sciences 2019年第8期120卷 239-260页

作者： Chang-Chun Lee pei-Chen huang Department of Power Mechanical Engineering National Tsing Hua UniversityNo.101Section 2Kuang-Fu RoadHsinchu 30013Taiwan

This research reviews the application of computational mechanics on the properties of nano/micro scaled thin films,in which the application of different computational methods is *** concept and fundamental theories of concerned applications,material behavior estimations,interfacial delamination behavior,strain engineering,and multilevel modeling are thoroughly ***,an example of an interfacial adhesion estimation is presented to systematically estimate the related mechanical reliability issue in the microelectronic *** presented results show that the peeled mode fracture is the dominant delamination behavior of layered material system,with high stiffness along the bonding ***,the shear mode fracture being dominated as the polymer cover plate with low moduli is *** occurrence of crack advance is also significantly influenced by the interfacial crack length and applied ***,this paper could serve as a guideline of several engineering cases with the assistance of computational mechanics.

关键词： Computational mechanics mechanical responses nano/micro thin films

Concise,enantioselective total syntheses of both the proposed and revised structures of (-)-versiquinazoline H

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Chinese Chemical Letters 2020年第1期31卷 61-63页

作者： Jiang-Feng Wu pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen University

The enantioselective total synthesis of the putative structure of versiquinazoline H and three diastereomers has been achieved,which allowed the revision of the stereochemistry of this natural *** six-step total synthesis relied on the evolution of the strategy that we previously developed,which features a DMDO-triggered tandem *** modification of the lactamization step resulted in a significant improvement of yield that ensured the efficient total synthesis.

关键词： Alkaloids Total synthesis Tandem reaction Structural revision Protecting group-free

Key issues and algorithms of multiple-input-multiple-output over-the-air testing in the multi-probe anechoic chamber setup

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Science China(Information Sciences) 2022年第3期65卷 51-77页

作者： Huiling pei Xiaoming CHEN Xiaoyu huang Xiaobo LIU Xiaotong ZHANG Yi huang School of Information and Communications Engineering Xi'an Jiaotong University College of Electrical Engineering Zhejiang University Interdisciplinary Institute of Neuroscience and Technology Zhejiang University Department of Electrical Engineering and Electronics University of Liverpool

Multiple-input-multiple-output(MIMO) over-the-air(OTA) testing plays a key role in the research and development of wireless devices. MIMO OTA testing is necessary for the fifth generation(5 G)wireless products, in which conventional radio frequency ports may be inaccessible. The performances of the test device can be evaluated in a repeatable and reliable way under laboratory conditions in OTA tests,which might not be feasible in conducted tests. Many efforts have been devoted to OTA test research and some achievements have been made. This paper mainly summarizes the channel emulation algorithms for two-dimensional user equipment and three-dimensional base station OTA testing in the anechoic chamber setup. In addition, the requirements of the test system design are also discussed in this paper, including the selection of the number of OTA probes, the size of the test zone, the physical dimension of the setup, and the flexible probe selection algorithm of the three-dimensional base station OTA setup. In addition, some novel test methods for 5 G radio devices are also discussed.

关键词： MIMO OTA testing multi-probe anechoic chamber 5G spatial channel

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Enantioselective total syntheses of marine natural products(+)-cylindricines C,D,E and their diastereomers

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Organic Chemistry Frontiers 2022年第1期9卷 58-63页

作者： Ying-Hong huang Zhan-Jiang Liu pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005P.R.China

A seven-step total synthesis of(+)-cylindricine D and epi-cylindricine D is *** efficiency relies on the highly diastereoselective reductive bis-functionalization of N,O-protected(S)-pyroglutaminol by our recently improved protocol to build the N-α-tert-alkylamine motif,and a telescoped one-step fourreaction protocol to build the fused bicyclic ring system.(+)-Cylindricine C and its 2-epimer were synthesized by essentially the same sequence in eight *** of the latter then delivered(+)-cylindricine E and its 2-epimer,respectively.

关键词： latter steps essentially

Sinistral portal hypertension associated with pancreatic pseudocysts - ultrasonography findings: A case report

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World Journal of Clinical Cases 2021年第2期9卷 463-468页

作者： Bei-Bei Chen pei-Yuan Mu Jing-Tai Lu Gong Wang Rui Zhang Dan-Dan huang Dong-Hua Shen ting-ting Jiang Department of Ultrasound Postgraduate Training Base of Jinzhou Medical UniversityThe PLA Rocket Force Characteristic Medical CenterBeijing 100088China Department of Ultrasound The PLA Rocket Force Characteristic Medical CenterBeijing 100088China

BACKGROUND Sinistral portal hypertension associated with pancreatic pseudocysts is rare,often caused by extrinsic compression of splenic vein,the follow-up examinations by ultrasonography for early diagnosis are quietly necessary since haematemesis,a life-threatening *** studies have reported the ultrasonography findings of sinistral portal *** SUMMARY A 52-year-old man presented with acute abdominal pain after drinking,steatorrhea,weight loss and accidentally melena in the past 2 *** underwent ultrasound-guided fine needle aspiration in other hospital and diagnosed with pancreatic *** imaging,in our department,appeared as cystic heterogeneous hypoechoic area with the size of 4.7 cm×3.8 cm that located posterior to the body and tail of pancreas,adjacent to splenic vein associated with thrombosis resulted from *** incrassated to approximately 7.3 cm,but no dilation of main portal vein was *** Doppler Flow Imaging demonstrated the formation of splenic venous collateral,nevertheless no significantly flow signals was observed in splenic *** Doppler revealed that the peak velocity of splenic venous collateral was 18.4 cm/s with continuous *** confirmed sinistral portal hypertension associated with pancreatic pseudocysts,subsequently distal pancreatectomy combined with splenectomy and partial gastrectomy was *** It’s important clinically to know the ultrasound appearance of sinistral portal hypertension associated with pancreatic pseudocysts for sonographer and physician.

关键词： Sinistral portal hypertension Pancreatic pseudocysts Ultrasonography imaging Upper gastrointestinal hemorrhage Splenic vein Case report

Cross-Coupling of Secondary Amides with Tertiary Amides: The Use of Tertiary Amides as Surrogates of Alkyl Carbanions for Ketone Synthesis

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Chinese Journal of Chemistry 2019年第9期37卷 887-891页

作者： Shu-Ren Wang pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China

In recent years,exciting progress has been made in the field of direct transformation of amides,nevertheless,the condensation between two amides remains rare and restricted to homo-coupling ***,we report the cross-coupling of secondary amides with tertiary amides,which provides a synthesis of ketones under mild conditions,and features the use of tertiary amides as surrogates of alkyl *** method relies on the coupling of enamines,generated from tertiary amides by catalytic partial reduction of tertiary amides with Vaska's catalyst,with nitrilium ions,formed in situ from secondary amides via activation with trifluoromethanesulfonic anhydride,and on the subsequent deformylation.

关键词： Secondary Amides Tertiary Amides Alkyl Carbanions

FIFAWC:a dataset with detailed annotation and rich semantics for group activity recognition

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Frontiers of Computer Science 2024年第6期18卷 271-272页

作者： Duoxuan pei Di huang Yunhong WANG State Key Laboratory of Software Development Environment School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Intelligent Recognition and Image Processing Lab. School of Computer Science and EngineeringBeihang UniversityBeijing 100191China

1 *** Activity Recognition(GAR),which aims to identify activities performed collectively in videos,has gained significant attention *** conventional action recognition centered on single individuals,GAR explores the c... 详细信息

关键词： has collective gained

Research on sentiment terms extraction and visualization of character sentimental interactions in A Dream of Red Mansions

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The Journal of China Universities of Posts and Telecommunications 2022年第2期29卷 24-32页

作者： huang pei Zhang Meng Wan Liu Lei Xuanzheng School of Digital Media and Design Arts Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Network System and Network Culture Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

In the context of interdisciplinary research,using computer technology to further mine keywords in cultural texts and carry out semantic analysis can deepen the understanding of texts,and provide quantitative support and evidence for humanistic *** on the novel A Dream of Red Mansions,the automatic extraction and classification of those sentiment terms in it were realized,and detailed analysis of large-scale sentiment terms was carried *** encoder representation from transformers(BERT) pretraining and fine-tuning model was used to construct the sentiment classifier of A Dream of Red *** terms of A Dream of Red Mansions are divided into eight sentimental categories,and the relevant people in sentences are extracted according to specific *** also tries to visually display the sentimental interactions between Twelve Girls of Jinling and Jia Baoyu along with the development of the *** overall F_(1) score of BERT-based sentiment classifier reached 84.89%.The best single sentiment score reached 91.15%.Experimental results show that the classifier can satisfactorily classify the text of A Dream of Red Mansions,and the text classification and interactional analysis results can be mutually verified with the text interpretation of A dream of Red Mansions by literature experts.

关键词： A Dream of Red Mansions sentiment term extraction character sentiment interaction bidirectional encoder representation from transformers(BERT) data visualization