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Frontiers of Environmental Science & Engineering 2024年第3期18卷 143-159页

作者： Junge Xu Dong Wang Die Hu Ziwei Zhang Junhong Chen Yingmu Wang Yifeng Zhang College of Civil Engineering Fuzhou UniversityFuzhou 350116China China nuclear Power Engineering Co. Ltd.Shenzhen 518120China Department of Environmental&Resource Engineering Technical University of DenmarkLyngby DK-2800Denmark

Iron-based catalysts have been widely used to treat refractory organic pollutants in *** this paper,magnetic Co-γ-Fe_(2)O_(3)was synthesized by a facile tartaric acid-assisted hydrothermal method,and Co-γ-Fe_(2)O_(3)/MoS_(2) nanocomposite catalyst was obtained via in situ growth of MoS_(2) nanosheets on Co-γ-Fe_(2)O_(3)*** nanocomposite catalysts were used to decompose bisphenol A(BPA)by activating peroxymonosulfate(PMS).It was shown that only 0.15 g/L catalyst and 0.5 mmol/L PMS degraded 10 mg/L of BPA(99.3%within 10 min)in the pH range of 3–*** was activated due to redox cycling among the pairs Co(III)/Co(II),Fe(III)/Fe(II),and Mo(VI)/Mo(IV).Quenching experiments and electron paramagnetic resonance spectroscopy demonstrated that both radical and non-radical pathways were involved in BPA degradation,in which active radical sulfate radical and non-radical singlet oxygen were the main reactive oxygen *** intermediates were identified by liquid chromatography-coupled mass spectrometry,and three possible BPA degradation pathways were *** toxicity of several degradation intermediates was lower,and Co-γ-Fe_(2)O_(3)/MoS_(2) exhibited excellent reusability and could be magnetically recovered.

关键词： magnetic Co-γ-Fe_(2)O_(3) /MoS_(2) Hydrothermal method Bisphenol A Degradation pathways Toxicity analysis

AN INTERMOLECULAR ^(13)C{~1H} nuclear OVERHAUSER EFFECT FOR THE CARBON OF CCl_4 IN POLYMER SOLUTIONS

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Chinese Journal of Polymer Science 1991年第2期9卷 184-187页

作者：晏欣王德华钱保功 Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics Academia Sinica Wuhan

An intermolecular ^(13)C{~1H} NOE of CCl_4 in the solutions of polystyrene and polybutadiene and their copolymers was observed. The results show that the defined polymer-CCl_4 interaction variable has a linear relation with the polymer composition and the difference of solubility parameters and exponentially depends on the reciprocal of temperature.

关键词： Intermoecular NOE Polymer-CCI4 interaction variable.

Spin-Exchange Collisions of the Ground State of Cs Atoms in a High magnetic Field

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Chinese Physics Letters 2000年第3期17卷 191-193页

作者： FU Li-Ping LUO Jun ZENG Xi-Zhi Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

Cs atoms were optically pumped with a Ti:sapphire laser in a magnetic field of 1.516 *** absorption spectra and populations of Zeeman sublevels of the ground state of Cs in N2 gas at various pressures(5,40,and 80 Torr)were *** results show that in a high magnetic field,the combined electron-nuclear spin transition(Hip-Hop transition)j which is mainly induced by the collision modification 8a(J•I)of hyperHne interaction,is an important relaxation mechanism at high buffer-gas pressures.

关键词： pumped relaxation collision

Implementation of a Quantum Algorithm for Deutsch- Jozsa Problem with Improved nuclear magnetic resonance Sequences

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Chinese Physics Letters 1999年第9期16卷 692-694页

作者： ZHANG Yan LUO Jun XIAO Li FU Li-ping QIU Jian-qing ZENG Xi-zhi YE Chao-hui Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

A quantum algorithm for Deutsch-Jozsa problem was implemented by nuclear magnetic resonance of benzene with heteronuclear decoupling during the readout period. It was demonstrated that decoupling can not only remove the undesired long-range couplings but also save the frequency space taken up by nuclear spins, which was expected to be important when scaling to large systems, and also to enhance the signal-to-noise ratio.

关键词： remove desired scaling

Mechanistic Insight into Ethanol Dehydration over SAPO-34 Zeolite by Solid-state NMR Spectroscopy

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Chemical Research in Chinese Universities 2022年第1期38卷 155-160页

作者： ZHOU Xue WANG Chao CHU Yueying WANG Qiang XU Jun DENG Feng National Centre for magnetic resonance in Wuhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071P.R.China

The reaction mechanism of ethanol dehydration over SAPO-34 zeolite is investigated by using solid-state NMR spectroscopy. SAPO-34 zeolites with different Si contents are prepared and their acidities are characterized by NMR experiments. The higher content of stronger Brønsted acid sites is correlated to the higher Si content. The adsorption of ethanol on the Brønsted acid sites in SAPO-34 leads to the formation of frustrated Lewis pairs(FLPs). Surface ethoxy species is observed by the dehydration of the FLP sites at room temperature, which can be further converted into ethene products. The decomposing of diethyl ether over Brønsted acid sites is responsible for the formation of ethoxy species at higher reaction temperatures. Triethyloxonium ions are formed in the reaction. A plausible reaction mechanism is proposed for the dehydration of ethanol over SAPO-34.

关键词： Ethanol dehydration SAPO-34 Intermediate Reaction mechanism Solid-state NMR

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MENGTING HE YUJING CAO JUNJIE LIN ZHIPING JU BOTAO WU E WU State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and Shanghai Key Laboratory for magnetic resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon

A New Density Operator Formalism for Describing nuclear magnetic resonance Experiments

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Science China Mathematics 1994年第12期37卷 1484-1497页

作者：林东海吴钦义 Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics Academia Sinica Wuhan 430071 PRCLaboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics Academia Sinica Wuhan 430071 PRC

A density operator formalism has been proposed to describe the evolution of two-spin-1/2 systems in nuclear magnetic resonance experiments:The formalism is particularly convenient and has distinct physical meaning for describing the evolution of spin systems under the Hamiltonian containing non-commutable terms. Some examples are presented to demonstrate the new formalism.

关键词： nuclear magnetic resonance density operator evolution of spin systems.

Li Plating on Carbon Electrode Surface Probed by Low-Field Dynamic nuclear Polarization ^(7)Li NMR

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Chinese Physics Letters 2021年第12期38卷 33-37页

作者： Zhekai Zhang Jiyu Tian Junfei Chen Yugui He Chaoyang Liu Xinmiao Liang Jiwen Feng State Key Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Center for Magnetic ResonanceKey Laboratory of Magnetic Resonance in Biological SystemsWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China

Lithium deposition on graphite electrode not only reduces fast-charging capability of lithium ion batteries but also causes safety ***,a low-field^(7)Li dynamic nuclear polarization(DNP)is used to probe Li plating on the surfaces of three types of carbon electrodes:hard carbon,soft carbon and *** to the strong Fermi contact interaction between^(7)Li and conduction electrons,the^(7)Li nuclear-magnetic-resonance(NMR)signal of Li metal deposited on electrode surface could be selectively enhanced by *** is suggested that low-field^(7)Li DNP spectroscopy is a sensitive tool for investigating Li deposition on electrodes during charging/discharging processes.

关键词： NMR electrode charging

Observation of the relaxivity and thickness of surface phase in porous rock with the combination of PFG NMR and relaxation measurements

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Science China Mathematics 1996年第9期39卷 974-980页

作者：肖立志杜有如叶朝辉 (Laboratory of magnetic resonance and Atomic and Molecular Physics Wuhan Institute of Physics Chinese Academy of Sciences Wuhan 430071 China)

nuclear magnetic resonance (NMR) relaxation of fluids in porous media is affected by the solid-liquid interface. Quantitative determination of the surface relaxivity is significantly important for both investigation and application of relaxation mechanisms in porous media. A method to estimate the surface relaxivity with the combination of relaxation and diffusion measurements is proposed. According to this method, a criterion for testing the current diffusion and relaxation theory for porous media is available.

关键词： rock surface relaxivity PFG NMR Bi-exponential decomposition.

Rydberg-Atom Terahertz Heterodyne Receiver with Ultrahigh Spectral Resolution

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Chinese Physics Letters 2024年第8期41卷 17-21页

作者： Zhenyue She Xiaojie Zhu Yayi Lin Xianzhe Li Xiaolin Yang Yanfei Shang Yuqin Teng Haitao Tu Kaiyu Liao Caixia Zhang Xiaohong Liu Jiehua Chen Wei Huang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials South China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China GPETR Center for Quantum Precision Measurement South China Normal UniversityGuangzhou 510006China State Key Laboratory of magnetic resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Atomic Frequency Standards Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Wuhan Institute of Quantum Technology Wuhan 430206China

Terahertz heterodyne receivers with high sensitivity and spectral resolution are crucial for various ***,we present a room-temperature atomic terahertz heterodyne receiver that achieves ultrahigh sensitivity and frequency *** a signal frequency of 338.7 GHz,we obtain a sensitivity of 2.88±0.09V·cm^(−1)·Hz^(−1/2) for electric field *** calibrated linear dynamical range spans approximately 89 dB,ranging from−110 dBV/cm to−21 dBV/*** demodulate a 400 symbol stream encoded in 4-state phase-shift keying,demonstrating excellent phase detection *** scanning the frequency of the local oscillator,we realize a terahertz spectrometer with Hz level frequency *** resolution is more than two orders of magnitude higher than that of existing terahertz *** demonstrated terahertz heterodyne receiver holds promising potential for working across the entire terahertz spectrum,significantly advancing its practical applications.

关键词： magnitude holds resolution