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Metal-Free Arylsulfonyl Radical Triggered Cascade Cyclization of Phenyl-Linked 1,6-Enynes:Synthesis of 2,3-Dihydro-1H-indenes and 10a,11-Dihydro-10H-benzo[b]fluorines

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Chinese Journal of Chemistry 2022年第23期40卷 2756-2762页

作者： Lin-Ping Hu De-Run Zhang Xiao-Hong Huang Feng-Lin Liu Xia Li Ming-Yu Teng Guo-Li Huang School of Chemistry and Chemical Engineering Yunnan Normal UniversityKunmingYunnan 650500China Department of Library Yunnan Normal UniversityKunmingYunnan 650500China

Aryl sulfonyl radical triggered cascade cyclization of phenyl-linked 1,6-enynes for the synthesis of biologically important indenes containing alkenyl C—X bonds and 10a,11-dihydro-10H-benzo[b]fluorines is *** these radical cascade processes,three new chemical bonds,including C—S,C—C,and C—X bonds,and three C—C bonds are formed in one *** method is attractive and valuable due to its metal-free,mild reaction conditions,broad substrate scope and good functional group tolerance.

关键词： Radical reactions Cyclization Enynes Aryl sulfonyl Indenes

Point defect states of a hollow cylinder in two-dimensional phononic crystal

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Chinese Physics B 2012年第6期21卷 324-328页

作者：高晓薇陈世波陈建兵郑勤红杨海 Physics Department Kunming University Department of Physics Yunnan Normal University Department of Information Management Yunnan Normal University

Point defect states in two-dimensional phononic crystal of a hollow mercury cylinder in a water host are studied. An improved plane expansion method combined with the supercell technique is used to calculate the band gaps and the pressure distribution at the defect position. The sonic pressure of defect modes shows that the waves are localized at or near the defect. As the filing fraction increases, more defect modes appear in the band gaps.

关键词： phononic crystal point defect cavity defect hollow cylinder

Leveraging Structured Information from a Passage to Generate Questions

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Tsinghua Science and Technology 2023年第3期28卷 464-474页

作者： Jian Xu Yu Sun Jianhou Gan Mingtao Zhou Di Wu Key Laboratory of Educational Informatization for Nationalities Yunnan Normal UniversityKunming 650500China School of Information Science and Technology Yunnan Normal UniversityKunming 650500China yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming 650500China School of Information Engineering Qujing Normal UniversityQujing 655011China

Question Generation(QG)is the task of utilizing Artificial Intelligence(AI)technology to generate questions that can be answered by a span of text within a given *** research on QG in the educational field struggles with two challenges:the mainstream QG models based on seq-to-seq fail to utilize the structured information from the passage;the other is the lack of specialized educational QG *** address the challenges,a specialized QG dataset,reading comprehension dataset from examinations for QG(named RACE4QG),is reconstructed by applying a new answer tagging approach and a data-filtering strategy to the RACE ***,an end-to-end QG model,which can exploit the intra-and inter-sentence information to generate better questions,is *** our model,the encoder utilizes a Gated Recurrent Units(GRU)network,which takes the concatenation of word embedding,answer tagging,and Graph Attention neTworks(GAT)embedding as *** hidden states of the GRU are operated with a gated self-attention to obtain the final passage-answer representation,which will be fed to the *** show that our model outperforms baselines on automatic metrics and human ***,the model improves the baseline by 0.44,1.32,and 1.34 on BLEU-4,ROUGE-L,and METEOR metrics,respectively,indicating the effectivity and reliability of our *** gap with human expectations also reflects the research potential.

关键词： automatic Question Generation(QG) RACE4QG dataset Answer-Oriented GAT(AO-GAT) attention mechanism structured information

MULTIPLICITY OF SOLUTIONS FOR A QUASILINEAR ELLIPTIC EQUATION

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Acta Mathematica Scientia 2016年第2期36卷 549-559页

作者：吴科吴鲜 Department of Mathematics Yunnan Normal University

We study a quasilinear elliptic equation with polynomial growth coefficients. The existence of infinitely many solutions is obtained by a dual method and a nonsmooth critical point theory.

关键词： Quasilinear equation dual method critical point nonsmooth analysis

Hierarchical porous cellulose/lanthanide hybrid materials as luminescent sensor

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Journal of Rare Earths 2018年第10期36卷 1036-1043页

作者： Wentao Fan Jiaojiao Du Junfeng Kou Zeyu Zhang Fengyi Liu College of Chemistry and Chemical Engineering Yunnan Normal University

Photoluminescent hybrid materials containing carboxymethyl cellulose and lanthanide ions（Eu3＋, Tb3＋）were prepared by a facile method under ambient conditions. Lanthanide ions were covalently grafted to the cellulose framework through coordination with the carboxylic groups of the cellulose. Hybrid materials were fabricated as hydrogel and aerogel. As shown by SEM and pore parameters, aerogel materials which were obtained by supercritical CO2 drying show hierarchical porous structure. The photoluminescence spectrum of the hybrid materials shows the characteristic red emission of Eu3＋ ion and green emission of Tb3＋. Further luminescent investigations reveal that these hybrid materials can detect Fe3＋ with relative selectivity and high sensitivity, which suggests that the hybrid materials could be a promising luminescent probe for selectively sensing Fe3＋ ion.

关键词： Lanthanide Cellulose Hybrid materials Luminescent sensor Rare earths

SIGN-CHANGING SOLUTIONS FOR p-BIHARMONIC EQUATIONS WITH HARDY POTENTIAL IN R^N

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Acta Mathematica Scientia 2017年第3期37卷 593-606页

作者：杨瑞瑞张薇刘祥清 Department of Mathematics Yunnan Normal University School of Mathematics and Statistics Yunnan University

In this article, by using the method of invariant sets of descending flow, we obtain the existence of sign-changing solutions of p-biharmonic equations with Hardy potential in RN.

关键词： Sign-changing solutions p-biharmonic equations Hardy potential

η string formation in QCD chiral phase transition

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Chinese Physics C 2010年第4期34卷 444-447页

作者：徐晓梅傅永平李云德 Physics Department Yunnan Normal University Physics Department Yunnan University

In the paper we discuss the role of the axial U（1）A symmetry in the chiral phase transition using the U（Nf）R × U（Nf）L linear sigma model with two massless quark flavors. It is expected that above a certain temperature the axial U（1）A symmetry will be restored. A string-like static solution, the η string can be formed and detected in the ultrarelativistic heavy-ion collision process.

关键词： η string sigma model chiral phase transition

Color reproduction from desktop display to projector based on visual matching

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Chinese Optics Letters 2009年第8期7卷 748-752页

作者：韩卫军石俊生贺萍云利军 Color & Image Vision Lab Yunnan Normal University

We present a novel method of color reproduction from desktop displays to projectors via visual assessment. The model is based on visual matching nine color patches between a display and a projector. The effects of the method to improve color reproduction are tested for 30 samples by visual and color difference evaluations. The expeirmental results of visual evaluation show that the color reproduction is improved by 87.5%. The maximum, minimum, and average color differences between the displayed colors and the projected ones before and after correction are 28.94, 4.35, 16.78, 16.51, 0.64, and 3.51 △Eab^＊ units respectively, which are consistent with the results of visual evaluation.

关键词： Color

Influence of defect states on band gaps in the two-dimensional phononic crystal of 4340 steel in an epoxy

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Chinese Physics B 2012年第9期21卷 400-403页

作者：孔肖燕岳蕾蕾陈雨刘应开 Institute of Physics and Electronic Information Yunnan Normal University

The band structures of a new two-dimensional triangle-shaped array geometry of 4340 steel cylinders of square cross section in an epoxy resin were studied by the plane-wave expansion and supercell calculation method. The band gaps of this type of phononic crystals with different defects were calculated such as defect-free, 60° crystal linear defect states, 120° crystal linear defect states, and 180° crystal linear defect states. It was found that the band gap will emerge in different linear defects of the phononic crystals and the bandwidth of linear defect states is larger than that of the free-defect crystal by about 2.14 times within the filling fraction F = 0.1-0.85. In addition, the influence of the filling fraction on the relative width of the minimum band gap is discussed.

关键词： defect state band width number of band gap