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Rigid Dysprosium(Ⅲ)Single-Molecule Magnets Exhibit Preserved Superparamagnetism in Solution

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Chinese Journal of Chemistry 2022年第5期40卷 563-570页

作者： Xiali Ding Qiancheng Luo Yuanqi Zhai Xufeng Zhang Yi Lv Xinliang Zhang Chao Ke Chao Wu Yanzhen Zheng Frontier Institute of Science and Technology(FIST) State Key Laboratory of Mechanical Behavior for MaterialsMOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi'an Key Laboratory of Sustainable Energy and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China Department of Hepatobiliary Surgery and The First Affiliated Hospital of Xi'an Jiaotong University 277 West Yanta RoadXi'anShaanxi710061 China Department of Spine Surgery Honghui HospitalXi'an Jiaotong University76 Nanguo RoadXi'anShaanxi710054 China Department of Orthopaedics and Trauma Hong Hui HospitalCollege of MedicineXi'an Jiaotong University555 East Youyi RoadXi'anShaanxi710054 China

Molecules with long preserved magnetic moments are perceived as the smallest units for storing bytes,which could bring a new revolution for information technology.However,the rational design of such molecules remains challenging.Here two rigid adamantanol ligand based dysprosium(III)complexes([Dy(1-AdO)_(2)(py)_(5)]BPh_(4)-1 and[Dy(2-AdO)_(2)(py)_(5)]BPh_(4)-2)with pentagonal-bipyramidal coordination geometry and local D5h symmetry were successfully prepared,which display excellent single-molecule magnet(SMM)behavior(U_(eff)≈1835 K,T_(B)_(ZFC)≈24 K,T_(B)^(100s)≈17 K and T_(B)^(H)=23 K for 1;U_(eff)≈1756 K,T_(B)^(ZFC)≈20 K,T_(B)^(100s)≈16 K and T_(B)^(H)=23 K for 2)due to the much weakened vibration in low energy regimes.Remarkably,the large energy barriers and high blocking temperatures for these two complexes in solid states are well preserved in Solution.This is never observed in previous studies of SMMs,indicating that the adamantanol is rigid and can be introduced to make the composed molecules stable enough to maintain the solid state magnetic property in Solution.

关键词： Molecularmagnets Lanthanide D_(sh)-symmetry Superparamagnetism Solution

Solution evaporation processed high quality perovskite films

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Science Bulletin 2018年第23期63卷 1591-1596页

作者： Aqiang Liu Kang Liu Huimin Zhou Hongmei Li Xiaoqing Qiu Yang Yi Min Liu School of Physics and Electronics and Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of the Ministry of Education Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Institute of Super-microstructure and Ultrafast Process in Advanced Materials School of Physics and Electronics Central South University School of Chemistry and Chemical Engineering Central South University State Key Laboratory of Powder Metallurgy Central South University

Organic-inorganic hybrid perovskite solar cells(PSCs), due to their high power conversion efficiency(PCE) and low cost, have been considered as one of the most promising photovoltaic devices. Welldistributed large-grain perovskite crystals play an important role for light adsorption and charge transfer.While, high quality perovskite crystals closely relate to the preparation method. Generally, the preparation of perovskite films requires a nitrogen atmosphere and toxic anti-solvents, which hinder their practical applications. Here, we reported a novel and simple Solution evaporation process followed with a methylammonium iodide(MAI) Solution immersion to prepare high quality perovskite films. Porous lead iodide(PbI_2) films were firstly formed by evaporation of PbI_2 precursor Solution. The obtained porous PbI_2 films were completely transformed into well-distributed large-grain perovskite films after a quick MAI Solution immersion. As a result, the corresponding PCE was enhanced by 30% compared to that prepared with a regular sequential deposition. This Solution evaporation method provides a convenient and practical way for preparing high-quality perovskite films.

关键词： Perovskite Solution evaporation High-quality films Power conversion efficiency

Precipitation mechanism and microstructural evolution of Al2O3/ZrO2(CeO2) solid Solution powders consolidated by spark plasma sintering

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Journal of Materials Science & Technology 2020年第6期41卷 149-158页

作者： Wanjun Yu Yongting Zheng Yongdong Yu National Key Laboratory of Science and Technology on Advanced Composites in Special Environments and Center for Composite Materials and Structures Harbin Institute of TechnologyHarbin 150080China

It is difficult to synthesize Al2O3/ZrO2 solid Solution because of its low solubility under equilibrium solidification conditions.In this work,a new combustion synthesis combined with water atomization(CS-WA)method was developed to prepare supersaturated Al2O3/ZrO2(CeO2)solid Solution powders.The ultrahigh cooling rate supplied by CS-WA greatly extends solid solubility of Al2O3 in ZrO2.The precipitation mechanism of solid Solution was investigated by systematic heat treatments.The initial temperature of the metastable phase decomposed into Al2O3 and ZrO2 is 1050℃,and it could be completely precipitated at 1400℃in 0.5 h.The precipitated ZrO2 particles were uniformly dispersed in Al2O3 matrix and grew into submicron scale at annealing temperature of 1450℃.Subsequently,together with detailed microstructure,phase composition,as well as mechanical properties were collaboratively outlined to discuss spark plasma sintering(SPS)behavior.The solid Solution precipitated Al2O3 matrix and ZrO2 particles during the SPS process.Partial ZrO2 particles were uniformly distributed within Al2O3 matrix,while the residuary ZrO2 located at the grain boundaries and formed special transgranular/intergranular structure.The average size of nanoscale transgranular ZrO2 particles was only^11.5 nm.The compact ZrO2 toughened Al2O3 nano ceramic(N-ZTA)exhibits excellent mechanical properties.This work provides a guidance to produce nanostructured ZTA with high performance.

关键词： Solid Solution Precipitation Spark plasma sintering ZTA Transgranular/intergranular structure

Highly efficient and selective photocatalytic dehydrogenation of benzyl alcohol for simultaneous hydrogen and benzaldehyde production over Ni-decorated Zn_(0.5)Cd_(0.5)S solid Solution

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Journal of Energy Chemistry 2019年第3期28卷 71-77页

作者： Lei Zhang Daochuan Jiang Rana Muhammad Irfan Shan Tang Xin Chen Pingwu Du Hefei National Laboratory of Physical Science at the Microscale CAS Key Laboratory of Materials for Energy Conversion Department of Materials Science and Engineering iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) University of Science and Technology of China (USTC)

Photocatalytic conversion of solar energy into hydrogen and high value-added fine chemicals has attracted increasing attention. Herein, we demonstrate an efficient photocatalytic system for simultaneous hydrogen evolution and benzaldehyde production by dehydrogenation of benzyl alcohol over Nidecorated Zn_(0.5)Cd_(0.5)S solid Solution under visible light. The photocatalytic system shows an excellent hydrogen production rate of 666.3 μmol h^(-1) with high stability. The optimal apparent quantum yield of52.5% is obtained at 420 nm. This noble-metal-free photocatalytic system displays much higher activity than pure Zn_(0.5)Cd_(0.5)S and Pt-loaded Zn_(0.5)Cd_(0.5)S solid Solution. Further studies reveal that the metallic Ni nanocrystals play an important role in accelerating the separation of photogenerated charge carriers and the subsequent cleavage of α-C–H bond during dehydrogenation of benzyl alcohol.

关键词： Photocatalysis Benzyl alcohol oxidation Hydrogen production Nickel Solid Solution Charge separation

Efficient Calculation of Absorption Spectra in Solution:Approaches for Selecting Representative Solvent Configurations and for Reducing the Number of Explicit Solvent Molecules

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物理化学学报 2018年第10期34卷 1106-1115页

作者： XUE Bai CHEN Tiannan SIEPMANN J.Ilja Department of Chemistry and Chemical Theory Center University of Minnesota207 Pleasant Street SEMinneapolisMN 55455-0240USA. Department of Chemical Engineering and Materials Science University of Minnesota421 Washington Avenue SEMinneapolisMN

Dye-sensitized solar cells(DSSCs) are one of the most promising renewable energy technologies. Charge transfer and charge transport are pivotal processes in DSSCs, which govern solar energy capture and conversion. These processes can be probed using modern electronic structure methods. Because of the heterogeneity and complexity of the local environment of a chromophore in DSSCs(such as solvatochromism and chromophore aggregation), a part of the solvation environment should be treated explicitly during the calculation. However, because of the high computational cost and unfavorable scaling with the number of electrons of high-level quantum mechanical methods, approaches to explicitly treat the local environment need careful consideration. Two problems must be tackled to reduce computational cost. First, the number of configurations representing the solvent distribution should be limited as much as possible. Second, the size of the explicit region should be kept relatively small. The purpose of this study is to develop efficient computational approaches to select representative configurations and to limit the explicit solvent region to reduce the computational cost for later(higher-level) quantum mechanical calculations. For this purpose, an ensemble of solvent configurations around a 1-methyl-8-oxyquinolinium betaine(QB) dye molecule was generated using Monte Carlo simulations and molecular mechanics force fields. Then, a fitness function was developed using data from inexpensive electronic structure calculations to reduce the number of configurations. Specific solvent molecules were also selected for explicit treatment based on a distance criterion, and those not selected were treated as background charges. The configurations and solvent molecules selected proved to be good representatives of the entire ensemble; thus, expensive electronic structure calculations need to be performed only on this subset of the system, which significantly reduces the computational cost.

关键词： Monte Carlo simulation Chromophore Spectra Solution

Nanopore sequencing: a rapid Solution for infectious disease epidemics

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Science China(Life Sciences) 2019年第8期62卷 1101-1103页

作者： Ying Cao Jing Li Xin Chu Haizhou Liu Wenjun Liu Di Liu Center for Emerging Infectious Diseases Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China Research Group of Computer Virology Center for Bacteria and Virus Resources and ApplicationWuhan Institute of VirologyChineseAcademy of SciencesWuhan430071China Institute of Microbiology Chinese Academy of SciencesBeijing100101China Bureau of Major R&D Programs Chinese Academy of SciencesBeijing100864China University of Chinese Academy of Sciences Beijing100049China

Emerging and re-emerging infectious diseases have given rise to a large number of human infections,morbidity,and heavy economic burden,including the Middle East respiratory syndrome caused by a coronavirus in 2012,global influenza pandemic caused by the H7N9 influenza A virus in2013,Ebola epidemic in West Africa in 2014,and Lassa fever epidemic in Nigeria in 2019.The healthcare war against viruses deserves constant surveillance due to the continuous emergence of new viruses and rapid evolution of existing viruses(Liu and Liu,2017).

关键词： pro RNA Nanopore sequencing a rapid Solution for infectious disease epidemics

Long-term stability of gentamicin sulfate-ethylenediaminetetraacetic acid disodium salt (EDTA-Na_2) Solution for catheter locks

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Journal of Pharmaceutical Analysis 2018年第6期8卷 386-393页

作者： Anne-Sophie Fiolet Elise Jandot Pauline Doucey Coralie Crétet Célia Brunel Christine Pivot Jean-Marc Ghigo Christophe Beloin David Lebeaux Fabrice Pirot Service Pharmaceutique Plateforme FRIPHARM Groupe Hospitalier Centre Edouard Herriot Hospices Civils de Lyon Unité de Génétique des Biofilms Département de Microbiologie Institut Pasteur Service de Microbiologie Unité Mobile de Microbiologie Clinique Assistance Publique-H?pitaux de Paris H?pital Européen Georges Pompidou Université Paris Descartes 12 rue de l'Ecole de Médecine Laboratoire de Recherche et Développement de Pharmacie Galénique Industrielle UMR 5305 Plateforme FRIPHARMF-69373 Faculté de Pharmacie Université Claude Bernard Lyon 1 8 avenue Rockefeller

A lock Solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports(TIVAP). In this study, fabrication, conditioning and sterilization processes of antimicrobial lock Solution(ALS) were detailed and completed by a stability study. Stability of ALS was conducted for12 months in vial(25 °C 7 2 °C, 60% 7 5% relative humidity(RH), and at 40 °C 7 2 °C, RH 75% 7 5%)and for 24 h and 72 h in TIVAP(40 °C 7 2 °C, RH 75% 7 5%). A stability indicating HPLC assay with UV detection for simultaneous quantification of gentamicin sulfate and EDTA-Na2 was developed. ALS was assayed by ion-pairing high performance liquid chromatography(HPLC) needing gentamicin derivatization, EDTA-Na2 metallocomplexation of samples and gradient mobile phase. HPLC methods to separate four gentamicin components and EDTA-Na2 were validated. Efficiency of sterility procedure and conditioning of ALS was confirmed by bacterial endotoxins and sterility tests. Physicochemical stability of ALS was determined by visual inspection, osmolality, pH, and sub-visible particle counting. Results confirmed that the stability of ALS in vials was maintained for 12 months and 24 h and 72 h in TIVAP.

关键词： Gentamicin-EDTA-Na2 loaded antimicrobial lock Solution Pharmaceutical compounding Stability indicating HPLC assay method Totally implantable venous access ports

A novel control Solution for improved trajectory tracking and LVRT performance in DFIG-based wind turbines

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Control Theory and Technology 2020年第1期18卷 43-55页

作者： Ahmad HASHEMI Christian CONFICONI Andrea TILLI The Center of Complex Automated Systems(CASY)at the Department of Electrical Electronic and Information Engineering(DEI)University of BolognaRisorgimento240136 BolognaItaly Sama Technical and Vocational training College Islamic Azad UniversityKermanshah BranchKermanshahIran

This paper presents a new control strategy for the rotor side converter of Doubly-Fed Induction Generator based Wind Turbine systems,under severe voltage dips.The main goal is to fulfill the Low Voltage Ride Through performance,required by modern grid codes.In this respect,the key point is to limit oscillations(particularly on rotor currents)triggered by line faults,so that the system keeps operating with graceful behavior.To this aim,a suitable feedforward-feedback control Solution is proposed for the DFIG rotor side.The feedforward part exploits oscillation-free reference trajectories,analytically derived for the system internal dynamics.State feedback,designed accounting for control voltage limits,endows the system with robustness and further tame oscillations during faults.Moreover,improved torque and stator reactive power tracking during faults is achieved,proposing an exact mapping between such quantities and rotor-side currents,which are conventionally used as controlled outputs.Numerical simulations are provided to validate the capability of the proposed approach to effectively cope with harsh faults.

关键词： Doubly-fed induction generator(DFIG) wind turbine(WT) feedforward-feedback control mapping Solution low voltage ride through(LVRT)

A simple method for solving unidirectional methane gas flow in coal seam based on similarity Solution

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International Journal of Mining Science and Technology 2018年第2期28卷 331-334页

作者： Zhou Yan Meng Qian Lin Baiquan Qin Jilong Zhou Guiping Key Laboratory of Gas and Fire Control for Coal Mines (China University of Mining & Technology) Ministry of Education School of Computer Science and Technology Jiangsu Normal University

The equation used to model the unidirectional flow of methane gas in coal seams is usually formulated as a nonlinear partial differential equation, which needs to be solved numerically with a computer program.Nevertheless, for people without access to the computer program, the conventional numerical method may be inconvenient. Thus, the objective here is to seek some method simpler than the conventional one for solving the flow problem. A commonly used model of the unidirectional methane gas flow is considered, where the methane adsorption is described by the Langmuir isotherm and the free gas is treated as real gas. By introducing the similarity Solution, a simple method for solving the flow model is proposed, which can be done on a hand calculator. It is shown by two examples that the gas pressure profile obtained by the proposed method agrees well with the direct numerical Solution of the flow model.

关键词： Coalbed methane Migration Unidirectional flow Similarity Solution Simplified solving Numerical method