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Synthesis and Mesophase Properties of Intraanular Functionized Shape-persistent Macrocycles Containing Dibenzo[fg,op]naphthacenes

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Chemical Research in Chinese Universities 2007年第1期23卷 35-43页

作者： CHENG xiao-hong HOEGER Sigurd Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education School of Chemistry and Material Engineering Yunnan University Kunming 650091 P. R. China University Karlsruhe Institute for Technic Chemistry and Polymer Chemistry Engesserstr. 18 76131 Karlsruhe Germany

On the basis of the C-C coupling reactions of dibenzo [ fg, op ] naphthacene bistriflate, which was obtained by the condensation of phenylacetates with 4-aryl-2,6-bis（2-bromo-4-methoxy-phenyl） pyrylium salts followed by palladium-catalyzed dehydrohalogenation, three shape-persistent macrocycles with dibenzonaphthacene corner pieces, a nanometer interior void, and intraanular oligoalkyl side groups were synthesized by the oxidative cyclization of the corresponding bisacetylenes under high-dilution conditions. Their thermotropic liquid crystalline properties were investigated by using polarizing microscopy and differential scanning calorimetry. All the three compounds showed nematic mesophases and belonged to discotic liquid crystals with inverted topology.

关键词： Dibenzo [ fg, op ] naphthacene Macrocycles Liquid crystal C-C coupling

Removing Impurity of cBN Crystal Prepared at High Pressure and High Temperature

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Chinese Physics Letters 2012年第3期29卷 224-226页

作者： JI xiao-Rui YANG xiao-hong Department of Preparatory Course Shenyang Institute of EngineeringShenyang 110136

The black cubic boron nitride(cBN)single crystal is synthesized by using hBN-LiH and hBN-Li_(3)N-B as the raw materials at high temperature and high pressure(HTHP).The colors of the cBN crystal synthesized in an hBN-Li_(3)N-B system vary from transparent yellow,half-transparent and then opaque black with the increasing B content in the raw *** is worth noting that a trigonal shadow is presented at the center of the cBN crystal synthesized in the hBN-Li_(3)N-B system but can not be found in the hBN-LiH *** the Raman spectrum,we find that the darkening and the trigonal shadow in the cBN crystal may be due to the presence of excess B *** above-mentioned phenomenon can be determined by removing impurity capacity and growth environment of the cBN crystal.

关键词： transparent removing Crystal

Various infection status and molecular evidence for horizontal transmission and recombination of Wolbachia and Cardinium among rice planthoppers and related species

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Insect Science 2013年第3期20卷 329-344页

作者： Kai-Jun Zhang xiao Han xiao-Yue hong Department of Entomology Nanjing Agricultural University Nanjing China

Wolbachia and Cardinium are widely distributed and are considered important for their ability to disturb reproduction and affect other fitness-related traits of their hosts. By using multilocus sequence typing （MLST）, RFLP （restriction fragment length poly- morphism） and 16S ribosomal DNA gene sequencing methods, we extensively surveyed Wolbachia and Cardinium infection status of four predominant rice planthoppers and one kind of leafhopper in different rice fields. The results demonstrated that Sogatellafurcifera （Horv^ith） and Laodelphax striatellus （Fallrn） were infected with the same Wolbachia strain （wStri）, while Nilaparvata lugens （St^l） and its closely related species Nilaparvata muiri China were infected with two phylogeneticlly distant strains, wLug and wMui, respectively. Three new Wolbachia strains （provisionally named wMfasl, wMfas2 and wMfas3） were detected in the leafhopper Macrostelesfascifrons （Stal）. Only S. furcifera was co-infected with Cardinium, which indicated that the distribution of Cardinium in these rice planthop- pers was narrower than that of Wolbachia. Unambiguous intragenic recombination events among these Wolbachia strains and incongruent phylogenetic relationships show that the connections between different Wolbachia strains and hosts were more complex than we expected. These results suggest that horizontal transmission and host associated special- ization are two factors affecting Wolbachia and Cardinium infections among planthoppers and their related species.

关键词： Cardinium infection status intragenic recombination rice planthopper,Wolbachia

Property(R)for Upper Triangular Operator Matrices

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Acta Mathematica Sinica,English Series 2023年第3期39卷 523-532页

作者： Li Li YANG xiao hong CAO School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710119P.R.China

Property(R)holds for an operator when the complement in the approximate point spectrum of the Browder essential approximate point spectrum coincides with the isolated points of the spectrum which are eigenvalues of finite *** A∈B(H)and B∈B(K),where H and K are complex infinite dimensional separable Hilbert *** denote by M_(C)the operator acting on H⊕K of the form M_(C)=(AC0B).In this paper,we give a sufficient and necessary condition for M_(C)∈(R)for all C∈B(K,H).

关键词： property(R) upper triangular operator matrix spectrum

Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： xiao-hong Yi Chong-Chen Wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

Serotonin suppresses lung ILC2 activation and proliferation

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Cellular & Molecular Immunology 2023年第5期20卷 546-547页

作者： xiao-hong Sun Oklahoma Medical Research Foundation Program in Arthritis and Clinical ImmunologyOklahoma CityOKUSA

In recent issue, Wang et al. [1] reported the suppressive effects of serotonin (5-hydroxytryptamine, 5-HT) on the activation and proliferation of group 2 innate lymphoid cells (ILC2s) in the lungs. ILC2s belong to a family of newly appreciated immune cells with a broad impact on a variety of immunological functions [2]. In particular, ILC2 activation has been implicated in the pathophysiology of asthma [3]. Although serotonin is known to play important roles in diverse physiological functions in the body [4], the effects of serotonin on innate lymphoid cells are less understood. The findings described here could potentially establish a new therapeutic avenue for respiratory disorders.

关键词： al. activation finding

Accelerating Optimization Design of Bio-inspired Interlocking Structures with Machine Learning

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Acta Mechanica Solida Sinica 2023年第6期36卷 783-793页

作者： Zhongqiu Ding hong xiao Yugang Duan Ben Wang School of Mechanical Engineering State Key Lab for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an 710049China

Structural connections between components are often weak areas in engineering *** nature,many biological materials with remarkablemechanical performance possess flexible and creative *** this work,we propose a novel bioinspired interlocking tab considering both the geometry of the tab head and neck,and demonstrate a new approach to optimize the bio-inspired interlocking structures based on machine *** neural networks for different optimization objectives are developed and trained using a database of thousands of interlocking structures generated through finite element *** show that the proposed method is able to achieve accurate prediction of the mechanical response of any given interlocking *** optimized designs with different optimization objectives,such as strength,stiffness,and toughness,are obtained efficiently and *** optimum design predicted by machine learning is approximately 7.98 times stronger and 2.98 times tougher than the best design in the training set,which are validated through additive manufacturing and experimental *** machine learning-based optimization approach developed here can aid in the exploration of the intricate mechanism behind biological materials and the discovery of new material designs boasting orders of magnitude increase in computational efficacy over conventional methods.

关键词： Interlocking structure Performance prediction Additive manufacturing Artificial neural network Finite element analysis

Vapor-assisted epitaxial growth of porphyrin-based MOF thin film for nonlinear optical limiting

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Science China Chemistry 2020年第8期63卷 1059-1065页

作者： Yi-hong xiao Zhi-Gang Gu Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Fabrication of metal-organic frameworks(MOFs)thin films has been an efficient way to expand their functionalities and ***,we use the vapor-assisted deposition(VAD)method to epitaxially grow a porphyrin-based MOF PCN-222 *** is,vapor source assists to deposit pre-treated precursor solution on quartz substrate to form a continuous PCN-222 ***,utilizing the post-treated encapsulation of functional carbon-based nanoparticles,the carbon nanodots(CND)and Pt doped CND(Pt/CND)are well loaded into the pores of PCN-222 film,the size(~3.1 nm)of which is highly close to the pore size of the corresponding MOF(~3.7 nm).The Z-scan results reveal that PCN-222 film exhibits high reverse saturable *** addition,encapsulation of carbon based nanodots into PCN-222 film could enhance the nonlinear optical limiting effect benefiting from the host-guest *** study serves to present both the available toolbox of thin film preparation and high potential for precise synthetic nanocomposite films in optical limiting devices.

关键词： metal-organic framework epitaxial growth porphyrin thin film nonlinear optical property

Comparison of Catalytical and Biological Activities for Substituted Polyoxotungstates Containing Ti and CpTi

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Chemical Research in Chinese Universities 2003年第1期19卷 20-23页

作者： LIU Jing-fu WANG xiao-hong 等 InstituteofPolyoxometalateChemistry FacultyofChemistryNortheastNormalUniversityChangchun130024P.R.China InstituteofPolyoxometalateChemistry FacultyofChemistryNortheastNormalUnivers

The effect of the functionallization of POMs on their properties was examined by the comparison between both titanium and its corresponding cyclopentadienyl subsituted polyoxocomplexes. The polarographic half wave potential of the complexes indicated that the effect of the functionallization of POMs increased the oxidizing ability of the polyoxoanions. The inhibitory effects of the CpTi polyoxocomplexes on tumor cells are higher than those of the corresponding titanium polyoxocomplexes, and the toxicity of the former is lower than that of the latter. The oxygenation reactions of cyclohexene, styrene, trans stilbene and maleic acid with PhIO or hydrogen peroxide(30% aqueous solution) catalyzed respectively by Ti and CpTi polyoxocomplexes were compared.

关键词： Polyoxometalate Titanium substituted polyoxotungstate 183 W NMR Antitumor activity