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Chinese Journal of Structural chemistry 2000年第3期19卷 181-186页

作者： WANG Geng ZHOU Zhao-Hui ZHANG Hui YE Jian-Liang WAN Hui-Lin department of chemistry and state key laboratory for physical chemistry of solid surface Xiamen UniversityXiamen361005

The sodium potassium citrato oxotungstate(VI) dimer, Na 4K 2〔W 2O 5\|(cit) 2〕·11H 2O (H 4cit = citric acid) was obtained by the reaction of sodium tungstate(VI) and excess potassium citrate monobasic (KH 3cit) in neutral solution. The crystal data for the title compound: monoclinic, C 12 H 30 K 2Na 4W 2O 30 , M r =1192.21, space group P2 1/n, a=17.427(4), b=10.022(2), c=18.637(3) , β=92.62(1)°, V=3252(2)  3, Z=4, D c =2.435 g/cm 3, μ( Mo Kα )=76.38 cm -1 , F( 000)=2288. The structure was refined to R =0.0434 for 6327 independent observed reflections with I>3σ(I) . The complex anion contains a quasi centrosymmetric (O 2W)O b(WO 2) core with a bent bridging oxo group 〔W-O b-W 175.0(4)°〕. Each citrate as tridentate ligand coordinates to a tungsten atom through the alkoxy, α carboxyl, and one β carboxyl group, while the other β carboxyl group remains uncoordinated. Principal dimensions are: W-O b 1.883(6) , (W=O t)av 1.715(6) , W-O (alkoxy) 1.959(6) , W-O ( α carboxy) 2.176(6)  and W-O ( β carboxy) 2.231(6) . The tungsten atom is located in a distorted octahedron environment.

关键词： oxotungstate(VI) citrate citric acid citrate method crystal structure

Light sheet microscope scanning of biointegrated microlasers for localized refractive index sensing

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Photonics Research 2024年第8期12卷 1673-1680页

作者： ROSS C.COWIE MARCEL SCHUBERT SUPA School of Physics and AstronomyUniversity of St Andrews Humboldt Centre for Nano and Biophotonics Department of ChemistryUniversity of Cologne

Whispering gallery mode (WGM) microlasers are highly sensitive to localized refractive index changes allowing to link their emission spectrum to various chemical, mechanical, or physical stimuli. Microlasers recently found applications in biological studies within single cells, in three-dimensional samples such as multicellular spheroids,or in vivo. However, detailed studies of biological samples also need to account for the structural heterogeneity of tissues and live animals, therefore requiring a combination of high-resolution microscopy and laser ***,we design and construct a light sheet fluorescence microscope with a coupled spectrometer for use in microlaser studies for combined high-resolution, high-speed imaging and WGM spectral analysis. The light sheet illumination profile and the decoupled geometry of excitation and emission hereby directly affect the lasing and sensing properties, mainly through geometric constraints and by light coupling effects. We demonstrate the basic working principle of microlaser spectroscopy under light sheet excitation and measure the absolute refractive index within agarose and in zebrafish tail muscle tissue. We further analyze the light coupling conditions that lead to the occurrence of two separate oscillation planes. These so-called cross modes can be scanned around the entire microlaser surface, which allows to estimate a surface-averaged refractive index profile of the microlaser environment.

关键词： High speed imaging Light sheet fluorescence microscopy Refractive index Scanning microscopy Second harmonic generation solid state lasers

Effects of surface migration of adsorbed species on desorption

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Science China chemistry 1995年第8期38卷 903-911页

作者：胡云行万惠霖蔡启瑞 department of chemistry and state key laboratory for physical chemistry of the solid surface Xiamen UniversityXiamen 361005China

The TPD equation with surface migration of adsorbed species on two kinds of adsorbingsites being put into consideration was *** to the equation,a series of theoretical TPD curveswere simulated by *** the results,one can see that surface migration of adsorbed species af-fects greatly the shape and position of the TPD peaks as well as the resolution power of TPD spectra.

关键词： temperature-programmed desorption adsorbed species surface migration simulation

Convergence from cluster to surface:ab initio calculations of Pd_n clusters

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Science China chemistry 1995年第9期38卷 1038-1045页

作者：徐昕王南钦吕鑫陈明旦张乾二 state key laboratory of physical chemistry on solid surface Department of ChemistryXiaman UniversityXiamen 361005China

The"Metallic state Principle"and a way to constitute the metallic basis set are proposed,the latter is a modification of atomic basis set based on the free electron theory in solid state ***_n dusters have been carefully studied by means of ab initio calculations with atomic and metallic basis *** rules,namely the"Ground state Principle",the"Lowest-Spin state Principle"and the"Metallic statePrinciple"have been investigated and the calculation results based on these three rules are compared with eachother in terms of metallic configuration of bulk Pd,d-band width,Fermi level,*** calculation resultsdemonstrate that the characteristic properties of bulk Pd may be reproduced to some extent even with a smallduster if the"Metallic state Principle"is adopted.

关键词： cluster-surface analogy "Ground state Principle" "Lowest-Spin state Principle" "Metallic "Metallic state Principle" Pd_n clusters.

Sodium metals for single emitter strong coupling:Alternative plasmonic candidates beyond noble metals

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 106-117页

作者： Yi Zhang Shuying Chen Yuning Han Xiulai Xu Lin Zhou National laboratory of solid state Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210008China School of Information and Electronic Engineering(Sussex Artificial Intelligence Institute) Zhejiang Gongshang UniversityHangzhou 310018China department of Physics&Astronomy University College LondonLondon WC1E 6BTUK state key laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

This work provides a theoretical investigation into the strong coupling between a single quantum emitter(QE)and the surface plasmons of sodium metals in two representative plasmonic systems,i.e.,the semi-infinite metal-dielectric interface and the metal nanoparticles(NPs)of monomer/dimer *** both configurations,sodium metals exhibit distinctly stronger coupling strength and lower optical loss in the optical region than their noble metal counterparts,demonstrating the ideal candidate characteristics for single-molecule-level strong couplings with distinctly facile operation *** results provide new insights into extreme light-matter interactions with potential applications in quantum information,optical sensors,quantum chemistry,etc.

关键词： sodium metals plasmonics single quantum emitter strong coupling pseudomode

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Synthesis and Spectroscopic Characterizations of an Insulinomimetic Peroxovanadate Complex in Aqueous Solution

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Chinese Journal of chemistry 2003年第7期21卷 746-750页

作者：蔡淑惠于贤勇陈忠万惠霖 department of Physics State Key Laboratory for Physical Chemistry of Solid SurfaceXiamen UniversityXiamenFujian 361005 China department of chemistry State Key Laboratory for Physical Chemistry of Solid SurfaceXiamen University XiamenFujian 361005 China department of PhysicsState Key Laboratory for Physical Chemistry of Solid SurfaceXiamen UniversityXiamenFujian 361005China

The reaction system of diperoxooxalatovanadate {K3[VO(O2)2-(C2O4)]·H2O, bpV(Oxa)} and imidazole was studied in an aqueous solution by 1D multinuclear (1H, 13C and 51V) NMR, 2D NMR diffusion ordered spectroscopy (DOSY), and variable temperature NMR techniques. It was shown that DOSY was a useful tool for the study of a mixture. All of the 1H and 13C NMR signals of the peroxovanadate (V) complexes were assigned. The NMR experimental results indicated that a new complex was formed through the coordination interactions between bpV(Oxa) and imidazole. The newly-formed complex is stable under the experimental condition. Electrospray ioniza-tion mass spectrometry (ESI-MS) provides positive evidence to support the conclusion.

关键词： diperoxovanadate imidazole synthesis DOSY,NMR ESI-MS

Synthesis of Compact NaA Zeolite Membrane by Microwave Heating Method

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Chinese Chemical Letters 2003年第8期14卷 874-876页

作者： Zhi Lin CHENG Zi Sheng CHAO Hui Lin WAN state key laboratory for physical chemistry of solid surface Department of ChemistryXiamen UniversityXiamen 361005

A continuous and dense NaA zeolite membrane was synthesized by microwave heating method while employing a multi-step seeding LTA zeolite with the average size of 120 nm. The gas H2/N2 mixture separating results indicated that the mixture selectivity increased with increasing of synthesis times. In addition, selectivity of the three-step synthesis was higher than the value(3.74) expected from Kundsen diffusion.

关键词： Microwave heating NaA zeolite membrane gas separation.

Electroless plating of Ni-Zn(Fe)-P alloy on carbon steel sheets

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中国有色金属学会会刊：英文版 2004年第z1期14卷 157-161页

作者： WANG Sen-lin WU Hui-huang College of Materials Science and Engineering Huaqiao University Quanzhou 362021 China state key laboratory for physical chemistry of solid surface Department of ChemistryXiamen University Xiamen 361005 China State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen University Xiamen 361005 China

The autocatalytic deposition of Ni-Zn(Fe)-P alloys were carried out on carbon steel sheets from bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and mole ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposit were studied. It is found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the mole fraction of zinc in the deposits never reaches high value, which is less than 18.0%. The structure and surface morphology of Ni-Zn(Fe)-P coatings were charactered by XRD and SEM. The alloys plated at all conditions consist of amorphous phase coexisting with a crystalline cubic Ni phase. The surface morphology of coating is dependent on the deposition parameters.

关键词： electroless plating nickel zinc

Interactions between Bioactive Diperoxovanadate Complexes and Imidazole: Insights into Their Solution Structures by NMR and ESI-MS

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Chinese Journal of Structural chemistry 2004年第6期23卷 511-518页

作者： YU Xian-Yong CAI Shu-Hui CHEN Zhong departments of Physics and chemistry State Key Laboratory for Physical Chemistry of Solid SurfaceXiamen UniversityXiamen 361005China state key laboratory of Structural chemistry Fuzhou 350002China

The interactions between four high bioactive diperoxovanadate complexes Kn[OV(O2)2L]mH2O (n = 1~3, m = 1~5, L = oxalate (abbr. oxa), picolinate (abbr. pic), bipyridine (abbr. bipy) and 1,10-phenanthroline (abbr. phen); their corresponding complexes abbreviated as bpV(oxa), bpV(pic), bpV(bipy) and bpV(phen), respectively) and imidazole (abbr. imi) in solution were studied by several NMR techniques: multinuclear (1H, 13C and 51V) and variable temperature 51V NMR. Competitive coordination interactions were observed and the order of the interaction strength of the four complexes with imidazole is as follows: bpV(oxa) > bpV(pic) > bpV(bipy) > bpV(phen), which is deeply affected by the identity of the ligands and has the same order as their inhibition effect toward bovine heart phosphotyrosyl protein phosphatase. The species [OV- (O2)2(imi)]- was formed in all cases. Both of the NMR data and equilibrium constants of the interaction systems were reported. The experimental results indicate that the species of bpV(oxa) and [OV(O2)2(imi)]- are six-coordinated, while bpV(pic), bpV(bipy) and bpV(phen) are seven- coordinated in solution. ESI-MS results support the conclusions obtained by NMR.

关键词： diperoxovanadate imidazole interaction NMR ESI-MS

Advanced cellulose-based materials toward stabilizing zinc anodes

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Science China chemistry 2024年第5期67卷 1465-1484页

作者： Zhijiang Li Xiang Chen Rui Zhang Taoyi Shen Jianchao Sun Zhongce Hu Lin Li Lanlan Yang Hou-Yong Yu College of Textile Science and Engineering(International Institute of Silk) Zhejiang Sci-Tech UniversityHangzhou 310018China state key laboratory for Modification of Chemical Fibers and Polymer Materials Donghua UniversityShanghai 201620China School of Environment and Material Engineering Yantai UniversityYantai 264005China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Rechargeable aqueous zinc metal batteries(RAZMBs) have received extensive attention for large-scale energy storage systems due to the merits of Zn anodes, including moderate volumetric and gravimetric energy density, low redox potential, abundant reserve, low cost and impressive intrinsic safety. However, Zn anodes suffer from a series of adverse reactions(dendrite growth,hydrogen evolution, and surface passivation) resulting in low Coulombic efficiency, large polarization, and unsatisfied cycling performance, which inevitably hinder the wide application of RAZMBs. To address the above issues, cellulose-based materials are widely used for Zn anode protection because of their unique physical and chemical properties and other advantages such as biocompatibility, non-toxicity, degradability and easy extraction. In order to better understand the current progress in cellulosebased materials for the Zn anode protection, we have classified and summarized the relevant literatures. In this review, we summarize and elaborate the causes of poor reversibility for Zn anodes, including dendrite formation, hydrogen evolution, and surface passivation. Subsequently, the effective strategies(anode interfacial engineering, gel electrolyte optimization, and separator modification) of cellulose-based materials toward stabilizing Zn anodes are overviewed. In the end, the existing challenges and prospects of cellulose-based materials in Zn anode protection are summarized to shed light on future work.

关键词： Zn anode cellulose anode interfacial engineering gel electrolyte optimization separator modification