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Science China Chemistry 2004年第4期47卷 295-300页

作者： zhang youming LIN Qi WEI Taibao College of Chemistry and Chemical Engineering Gansu Key Laboratory of Polymer Materials Northwest Normal University Lanzhou730070China College of Chemistry and Chemical Engineering Gansu Key Laboratory of Polymer Materials Northwest Normal University Lanzhou730070China College of Chemistry and Chemical Engineering Gansu Key Laboratory of Polymer Materials Northwest Normal University Lanzhou730070China

L-aspartic acid zinc was synthesized by a rapid and convenient method in high yield under microwave conditions, and its single crystal structure was analyzed by X-ray diffraction. The structure unit of the title compound is [Zn(L-Asp)(H2O)2]·H2O, which is a bicyclo-complex forming a spiral linear polymer via coordination bonds. The spiral linear polymers are assembled as a three-dimensional supramolecule by intermolecular hydrogen bonds. The crystal belongs to the orthorhombic crystal system, P2(1)2(1)2(1) space group, a=0.7830(3) nm, b=0.9369(4) nm, c=11.599(5) nm, α=β=γ=90.00°, V=0.8509(6) nm3, Z=4, Dc=1.955 g/cm3, F(000)=512, μ=2.289. The toxicity of the title compound is lower than that of glutamic acid zinc and zinc sulfate. Keywords L-aspartic acid - zinc - microwave - supramolecule - toxicity

关键词： L-aspartic acid zinc microwave supramolecule toxicity

The hydrogen sulfate recognition properties of azo-salicylaldehyde schiff base receptors

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Science China Chemistry 2008年第11期51卷 1051-1056页

作者： WEI TaiBao WANG Jun zhang youming College of Chemistry and Chemical Engineering Gansu Key Laboratory of Polymer MaterialsNorthwest Normal UniversityLan-zhou 730070China

Azo-salicylaldehyde Schiff base-typed receptors containing an acidic H-bond donor moiety were syn-thesized and characterized. The UV-Vis data indicate that these receptors could act as selective col-orimetric sensors for basic anions and acidic species hydrogen sulfate by different color changes in a water-containing medium. The experiment of Brφnsted acid-base reaction by adding the sodium hy-droxide or perchloric acid revealed that the mechanism of recognition of anions might be deprotona-tion/protonation of the OH fragments by interacting with different anions and that the deprotona-tion/protonation process is fully reversible. The deprotonation/protonation of the receptors is respon-sible for the dramatic color change.

关键词： Schiff base azo-salicylaldehyde phenolic hydroxy group anion recognition deprotonation/protonation

A metamaterial-free fluid-flow cloak

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National Science Review 2022年第9期9卷 212-218页

作者： Fuyang Tay youming zhang Hongyi Xu Honghui Goh Yu Luo Baile zhang Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University School of Electrical and Electronic Engineering Nanyang Technological University Centre for Disruptive Photonic Technologies Nanyang Technological University

The model of ide al fluid flow around a cylindrical obstacle exhibits a long-established physical picture,where originally straight streamlines are deflected over the whole space by the *** by transformation optics and metamaterials,recent theories have proposed the concept of fluid cloaking,which is able to recover the straight streamlines,as if the obstacle did not ***,such a cloak,similar to all previous transformation-optics-based devices,relies on complex metamaterials with inhomogeneous parameters and is difficult to *** we deploy the theory of scattering cancellation and report on the experimental realization of a fluid-flow cloak without *** clo ak is realized by engineering the geometry of the fluid channel,which effectively cancels the dipole-like scattering of the *** clo aking effect is demonstrated through the direct observation of recovered straight streamlines in the fluid *** work sheds new light on conventional fluid control and may find application in microfluidic devices.

关键词： invisibility cloaks metamaterials fluid-flow control

Contribution of Microbial Inter-kingdom Balance to Plant Health

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Molecular Plant 2019年第2期12卷 148-149页

作者： Chunlei zhang youming zhang Zhaojun Ding Yang Bai StateKeyLaboratoryofMicrobialTechnology ShandongUniversityQingdaoShandong266237China StateKeyLaboratoryofPlantGenomics InstituteofGeneticsandDevelopmentalBiologyChineseAcademyofScienceBeijing100101China CAS-JICCentreofExcellenceforPlantandMicrobialScience InstituteofGeneticsandDevelopmentalBiologyChineseAcademyofSciencesBeijing100101China “UniversityofChineseAcademyofSciences CollegeofAdvaneedAgriculturalSciencesBeijing100039China TheKeyLaboratoryofPlantDevelopmentandEnvironmentalAdaptationBiology MinistryofEducationCollegeofLifeSciencesShandongUniversityQingdaoShandong266237China

Soil-borne fungal and oomycetal pathogens cause devastating agricultural losses every year. The abundance and diversity of filamentous eukaryotes in the roots of healthy plants are in flue need by root-associated bact... 详细信息

关键词： Microbial Inter-kingdom Balance Plant Health filamentous eukaryotes

Syntheses Characterization of Chloro-cyclopentadienyltricarbonyl-molybdenum with β-Cyclodextrin Supramolecular

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Chemical Research in Chinese Universities 2001年第Z1期17卷 32-33页

作者： zhang youming Department of Chemistry Northwest Normal University

Organotransition metal complex have been extensively used as homogeneous catalysts in organic reactions and much effort has been paid to improve their activity and selectively. Cyclodextrins have been studied as a model of enzyme for selective catalysis. However, so far there are only a few reports on the inclusion compounds of organometallic complexes with cyclodextrins. Breslow et *** high acylation rates for β-CD using ferrocene derivatives and assumed β-CD substrate complexes as intermediate [1]..larad et al reported the preparation and propertics of cyclodextrin-ferrocen inclusion compounds as the first example of cyclodextrin inclusion compounds of organotransition metal complexes[2]. Song Le-Xin et al reported the supramolecular inclusion compound of β-cyclodextrin with cyclopentadieny-tricarbonylmanganese [3] .To our knowledge, there are no reports of inclusion compounds of β-CD with molybdenum organometallic complexes. In the present work we described the preparation and properties of the supramolecular of CpMo(CO)3Cl with β-CD in details.　　……

关键词： organometallic complexes preparation and properties ferrocene derivatives selective catalysis inclusion compound organic reactions metal complexes

Recent progress of electronic materials based on 2,1,3-benzothiadiazole and its derivatives:synthesis and their application in organic light-emitting diodes

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Science China Chemistry 2021年第3期64卷 341-357页

作者： youming zhang Jun Song Junie Qu Peng-Cheng Qian Wai-Yeung Wong Department of Applied Biology and Chemical Technology and Research Institute for Smart Energy1 The Hong Kong Polytechnic University(PolyU)Hung HomHong KongChina PolyU Shenzhen Research Institute Shenzhen 518057China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering.Shenzhen UniversityShenzhen 518060China Key Laboratoty of Environmental Functional Materials Technology and Application of Wenzhou City Institute of New Materials&IndustiyCollege of Chemistry&Materials Engineering.Wenzhou UniversityWenzhou 325035China

2,1,3-Benzothiadiazole(BT)and its derivatives are very important acceptor units used in the development of photoluminescent compounds and are applicable for the molecular construction of organic light-emitting diodes,organic solar cells and organic field-effect *** to their strong electron-withdrawing ability,construction of molecules with the unit core of BT and its derivatives can usually improve the electronic properties of the resulting organic *** this contribution,we review the synthesis of various polymers,small molecules and metal complexes with BT and its derivatives and their applications in organic light-emitting ***,the molecular design rules based on these cores are discussed.

关键词： 2,1,3-benzothiadiazole organic light-emitting diodes synthesis electronic properties photoluminescence

Fluorescence Studied of Dissociation Constant of Cyclodextrin With Phenol Derivatives

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Chemical Research in Chinese Universities 2001年第Z1期17卷 232-233页

作者： zhang youming Department of Chemistry Northwest Normal University

α-and β-cyclodextrins consisting of six and seven glucose residues respectively, have lipophilic cavities with different inner diameters. They form host-guest inclusion complexes with hydrophobic organic and organometallic guest molecules in aqueous solution. These host-guest complexes have proved to be excellent model systems for studying the nature of noncovalent bonding forces in aqueous media. They have provided valuable insights into the hydrophobic effect and London dispersion forces and are good model for understanding the specificity of enzyme substrate interactions [1] Evidence for the formation of inclusion complexes have been provided from calovimetric titration [2] NMR[33], circular dichroism[4], U V[1] and fluorescence spectra[5] and conductometric method[6] etc. H ere we report a new fluorimetric method for a study on the reaction of the host-guest inclusion complexes of cyclodextrin with phenols. Dissociation constants (Kd) of the inclusion complexes of some phenols with α-β-cyclodextrin are estimated based on the variation of the fluorescent intensity and modified Harad' equations.

关键词： inclusion complexes fluorescent intensity fluorescence spectra dispersion forces aqueous solution aqueous media nature of

A Highly Selective Fluorescent Chemosensor for Cu2＋

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Chemical Research in Chinese Universities 2015年第3期31卷 347-351页

作者： GUAN Jie zhang Peng WEI Taibao LIN Qi YAO Hong zhang youming Key Laboratory of Eco-environment-related Polymer Materials Ministry of Education Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical EngineeringNorthwest Normal University Lanzhou 730070 P.R.China

A new Zn2＋ probe L2-Zn（L2=naphthofuran carbonylhydrazone derivant） was synthesized as a fluores- cence chemosensor for Cu2＋, by which Cuz＋ ion could be detected with high selectivity and sensitivity in a wide pH range via a displacement ＂turn-off＂ signaling strategy. Whereas the coordination between Zn2＋ and L2 resulted in a considerable enhancement of typical luminescence of a naphthalofuran group in complex L2-Zn, the addition of Cu2＋ ion led to a dramatic decrease in the emission intensity of probe L2-Zn at about 503 nm（excitation at 423 nm）. The competitive fluorescent experiments showed that other metal ions, such as Hgz＋, Fe3＋, Ag＋, Ca2＋, Co2＋, Ni2＋, Cd2＋, Pb2＋, Zn2＋, Cr3＋ and Mg2＋ could not impact tile detection of Cu2＋. The detection limit of the novel probe L2-Zn for Cu2~ ion was as low as 2.3× 10 7 mol/L, which is far lower than the guideline value of 1.6× 10-5 mol/L of the United States Environmental Protection Agency.

关键词： Znic complex Fluorescent switch Copper ion Turn-off signal

Tetradentate cyclometalated platinum complex enables high-performance near-infrared electroluminescence with excellent device stability

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Chinese Chemical Letters 2023年第2期34卷 511-514页

作者： Chengjun Wu youming zhang Jingsheng Miao Kai Li Weiguo Zhu Chuluo Yang Shenzhen Key Laboratory of New Information Display and Storage Materials Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518055China Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications Changzhou UniversityChangzhou 213164China

Due to the high decay rate of the non-radiative transition of long wavelengths, the molecular design of efficient and stable near-infrared(NIR) electroluminescent materials remains a big challenge. Herein,a new tetradentate cyclometalated platinum(II) complex with an N∧C∧C∧N coordinated framework has been developed and used as a dopant for NIR organic light-emitting diodes(OLEDs). The complex exhibited a short-lived(0.5–1.5 μs) metal-to-ligand charge transfer(MLCT) excited state in doped and neat films. The resulting NIR OLEDs(λ_(EL)= 730 nm) achieved maximum external quantum efficiency(EQE_(max))of 5.2% and radiance of 74626 m W sr^(-1)m^(–2). Of note, the device exhibited excellent stability with operational lifetime of 119 h for LT_(90). This work demonstrated the great potential of tetradentate platinum(II)complexes in the field of NIR OLEDs.

关键词： Near-infrared emitter Phosphorescence Platinum complex OLED Operational lifetime

Sensitive and Selective Fluorescent and Colorimetric Sensor for Ag^＋ Based on the Supramolecular Self-Assembly in Semi-Water

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Chinese Journal of Chemistry 2017年第8期35卷 1311-1316页

作者： Taibao Wei Haili zhang Wenting Li Wenjuan Qu Junxia Su Qi Lin youming zhang Hong Yao Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of Education of ChinaKey Laboratory of Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhouGansu 730070China

Specific recognition of ultratrace levels of ions in semi-water using super-quicker methods is still a challenge for environmental monitoring. Herein we report a fluorescent and colormetric sensor （ZH） based on supramolecular self-assembly, whose structure was destroyed by the addition of ultratrace of silver ions. The process promoted either naked eye visible color changes or fluorescence intensity quenched in conjunction with a wide pH range. Systematic studies revealed very high selectivity （0.07 μmol/L） for silver ions, and other common cations, e.g., Hg^2＋, Cu^2＋, Cd^2＋, Pb^2＋ had nearly no influence on the sensing behavior. This sensor also served as a multiple use of component in sensing materials by addition of I^- into the mixture of ZH and Ag^＋（about 5 times）. What＇s more, ZH containing filter paper emerged distinct color and fluorescence changes upon exposure to silver （Ag^＋）, which could be used as a portable method to undertake field testing for Ag^＋.

关键词： supramolecular self-assembly silver (Ag^+) dual-channel aqueous solution