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Li,Na,and Cs-based metal-organic frameworks for room temperature phosphorescence applications

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science China Chemistry 2025年

作者： Jiaqi Ma Rui Feng Yanyuan Jia Mingshi Zhang Shuo Guo College of Chemistry and Chemical Engineering Inner Mongolia University School of materials science and Engineering Smart Sensing Interdisciplinary Science Center Nankai University & TKL of Metal and Molecule Based Material Chemistry Key laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University Department of Chemistry and Biochemistry University of California San Diego

The conventional design of metal-organic frameworks (MOFs) with room-temperature phosphorescence (RTP) mostly relies on using heavy metals,as the heavy atom effect can effectively increase the efficiency of intersystem crossing (ISC) to get a better phosphorescence *** the first time,we reported the highly efficient RTP of a lithium-based MOF IMU-101 with a lifetime (τ) of 299 ms and a quantum yield (QY) of 4.91%.In addition,MOFs IMU-102 and IMU-103,with sodium and cesium as metal nodes,were successfully *** phosphorescence properties of this series of alkali metal MOFs were systematically studied and *** crystallography and computational calculation show that the mechanism for achieving RTP for this material lies in the ultrashort coordination bond of Li,which enables the reduction of non-radiative ***-101,as a cheap and environmentally friendly room-temperature phosphorescent material,has been further developed into composite polymer inks and bulk *** makes them promising for applications in anti-counterfeiting and information encryption.

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A proposal for preparation of cluster states with linear optics

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Chinese Physics B 2021年第3期30卷 55-60页

作者： Le Ju Ming Yang Peng Xue Beijing computational science Research Center Beijing 100084China School of Physics and material science Anhui UniversityHefei 230601China

Measurement-based quantum computation in an optical setup shows great promise towards the implementation oflarge-scale quantum computation. The difficulty of measurement-based quantum computation lies in the preparation ofcluster state. In this paper, we propose the method of generating the large-scale cluster state, which is a platform formeasurement-based quantum computation. In order to achieve more complex quantum circuits, the preparation protocolof N-photon cluster state will be proposed as a generalization of the preparation of four- and five-photon cluster ***, our proposal is experimentally feasible.

关键词： measurement-based quantum computing cluster states linear optical elements

The energy release rate for hygrothermal coupling elastic materials

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Acta Mechanica Sinica 2006年第1期22卷 28-33页

作者： Fan Yang Jun Wang Dapeng Chen Institute of computational Engineering and science Southwest Jiaotong UniversityChengdu 610031 China Department of material science Fudan UniversityShanjzhai 200433. China

In the fracture problems of hydrophilic elastic materials under coupling effects of heat conduction, moisture diffusion and mechanical deformation, the conventional J-integral is no longer path independent. The value of J is unequal to the energy release rate in hygrothermal coupling cases. In the present paper, we derived a general form of the energy release rate for hygrothermal fracture problems of the hydrophilic elastic materials on the basis of energy balance equation in cracked areas. By introducing the constitutive relations and the essential equations of irreversible thermodynamics, a specific expression of the energy release rate was obtained, and the expression can be reformmulated as path independent integrals, which is equivalent to the energy release rate of the fracture body. The path independence of the integrals is then verified numerically.

关键词： Fracture Energy release rate J-integral Hygrothermal coupling problems

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key laboratory of Solidification Processing Northwestern Polytechnical University laboratory of computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

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AIM and ELF Analyses of Halogen Bonding in NCS ： BrCl Complexes

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Chinese Journal of Chemistry 2011年第11期29卷 2416-2420页

作者：李晓艳孙洁张雪英曾艳丽郑世钧孟令鹏 Institute of computational Quantum Chemistry College of Chemistry and Material Science Hebei Normal University Shijiazhuang Hebei 050016 China

The nature of halogen bonding in five complexes formed between the thiocyanate （NCS） radical and a BrC1 molecule was analyzed by quantum theory of atoms in molecules （QTAIM） and electron-localization function （ELF） in this paper. The calculated results show that the geometry of the halogen atom bonded at the N-atom is stable than those bonded at S- or C-atom. The molecular electrostatic potentials determine the geometries and stabilities of the complexes. The valence basin of the S- or N-atom in the electron-donating NCS radical is compressed and its population decreases during the process of formation of the halogen-bonded complexes.

关键词： NCS radical halogen bonding molecular electrostatic potentials atoms in molecules electron-local ization function

Energy transfer and frequency upconversion in Er^(3+)-Yb^(3+) codoped oxy-fluoro-tungstosilicate glasses

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Journal of Rare Earths 2012年第5期30卷 422-425页

作者：揭光涛赵高凌汪建勋韩高荣 State Key lab of Silicon material and Department of materials science and Engineering Zhejiang University

Er3＋-Yb3＋ codoped oxy-fluoro-tungstosilicate glasses with infrared-to-visible frequency upconversion luminescence were prepared by melting quenching in *** effects of Er3＋ doping on the optical properties of the samples were measured by means of techniques such as optical absorption spectra and photoluminescence *** results showed that intense green and red signals centered at 546 and 665 nm,corresponding to the 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3＋ by a multiphoton stepwise phonon-assisted excited-state absorption process,respectively,were simultaneously observed by exciting the samples with a diode laser operating at 980 nm at room *** upconversion process was found very sensitive to Er3＋ content at a constant Yb2O3 content of 5 mol.%.With the increase of Er3＋ content from 0.5% to 1.5%,the upconversion intensity increased *** increasing of Er3＋ content to 3.0% resulted in a significant fluorescence ***,the possible upconversion mechanisms were discussed based on the energy-matching conditions and the quadratic dependence on excitation power.

关键词： oxy-fluoro-tungstosilicate rare earth ions upconversion luminescence glass

The role of prior in image based 3D modeling： a survey

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Frontiers of Computer science 2017年第2期11卷 175-191页

作者： Hao ZHU Yongming NIE Tao YUE Xun CAO lab for computational Imaging Technology and Engineering School of Electronic Science and Engineering Nanjing University Nanjing 210023 China

The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to prior cate- gories, i.e., classical priors and specific priors. The classical priors including smoothness, silhouette and illumination are well studied for improving the accuracy and robustness of the 3D reconstruction. In recent years, various specific priors which take advantage of Manhattan rule, geometry template and trained category features have been proposed to enhance the modeling performance. The advantages and limitations of both kinds of priors are discussed and evaluated in the paper. Finally, we discuss the trend and challenges of the prior studies in the future.

关键词： prior information consistency-based stereo,smoothness illumination silhouette specific prior

Kinetics of Nitrogen Indiffusion in Czochralski Silicon Annealed in Nitrogen Ambient

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Chinese Physics Letters 2008年第2期25卷 648-650页

作者：李明马向阳杨德仁 State Key lab of Silicon materials and Department of material science and Engineering Zhejiang University Hangzhou 310027

By means of low-temperature （10 K） Fourier transform infrared absorption spectroscopy, the kinetics of nitrogen indiffusion in Czochralski （CZ） silicon annealed at 1150-1250℃ in nitrogen ambient is investigated. Moreover, the nitrogen diffusivities in CZ silicon at elevated temperatures deduced herein are in good agreement with those previously obtained in float-zone silicon, thus leading to the conclusion that the nitrogen indiffusion in CZ silicon at elevated temperatures is via nitrogen pairs.

关键词： SHALLOW THERMAL DONOR OXYGEN PRECIPITATION CRYSTALS COMPLEXES

Mass Spectrometric Studies of Selective Oxidation of n-Butane over a Vanadium Phosphorus Oxide Catalyst

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Chinese Journal of Chemical Engineering 2002年第2期10卷 177-182页

作者：陈标华黄晓峰李成岳梁日忠赵邦蓉 The Key lab of science and Technology of Controllable Chemical Reactions College of material science and Engineering Beijing University of Chemical Technology Beijing 100029 China

The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response technique. The reaction intermediates, buterie and furan, were found in the reaction effluent under near industrial feed condition (3% butane+15%O2), while dihydrofuran was detected at high butane concentration (12% butane, 5%O2). Some intermediates of MA decomposition were also identified. Detection of these intermediates shows that the vanadium phosphorus oxides are able to dehydrogenate butane to butene, and butene further to form MA. Based on these observations, a modified scheme of reaction network is proposed. The transient experiments show that butane in the gas phase may directly react with oxygen both on the surface and from the metal oxide lattice, without a proceeding adsorption step. Gas phase oxygen can be adsorbed and transformed to surface lattice oxygen but it can not participate in selective oxidation. Adsorbed oxygen leads to deep oxidation, while lattice oxygen leads to selective oxidation.

关键词： n-butane selective oxidation vanadium phosphorus oxide catalyst mass spectrometer reaction in- termediates transient response