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Synthesis and Pyrolysis of Soluble Cyclic Hf-Schiff Base Polymers

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Chinese Journal of Polymer Science 2021年第6期39卷 659-664,I0005页

作者： Yu-Huan wu Li Ye ya-Nan Sun wei-Jian Han Tong Zhao Key Laboratory of Science and Technology on High-tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China University ofChinese Academy of Sciences Beijing 100049China

Soluble Hf-containing polymers are significant processable precursors for the fabrication of ultra-high temperature *** this work,cyclic Hf-Schiff base polymers were synthesized via direct polymerization of hafnium alkoxide and bis-salen *** defined structure and molecular weight of the polymers were characterized by NMR spectroscopy,gel permeation chromatography and MALDI-TOF mass *** feed ratio of monomers regulated the molecular weight and solubility of the *** synthetic strategy features simple operation under ambient conditions,efficient reaction with high yield and cyclic polymers as the main *** Hf-Schiff base polymers were converted to HfC/C materials after pyrolysis under argon at 1600°C,which was identified by XRD measurements,elemental analyses and Raman *** work will inspire more precise and efficient synthesis and applications of metallopolymers.

关键词： Hf-containing polymer Schiff base Cyclic polymer Preceramic polymer Hafnium carbide

Direct and rapid detection of serum amino acid and monoamine neurotransmitters to assist the diagnosis of panic disorder

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Science China Chemistry 2025年第1期68卷 377-384页

作者： Shiwen Liu Xuerui Wan Meng Zhao Jiaqi Wang weilan wu Linlin You Yonggui Yuan Qian Xu Rong Gao Key Laboratory of Environmental Medicine Engineering Ministry of Education School of Public Health Southeast University Key Laboratory of Modern Toxicology of Ministry of Education Department of Hygienic Analysis and Detection School of Public HealthNanjing Medical University Department of Psychosomatics and Psychiatry Zhongda Hospital School of Medicine Southeast University

The measurement of amino acid and monoamine neurotransmitters（NTs） in serum plays a central role in the identification and monitoring of clinical panic disorder（PD）. However, the strong polarity and chemical heterogeneity of NTs make direct extraction and rapid detection extremely challenging. Herein, we developed a strategy that integrated solid phase extraction based on magnetic Fe3O4coated with polydopamine（Fe3O4@PDA） and direct analysis of mass spectrometry in real time（DART-MS） for quantification of 10 NTs. We systematically investigated the optimal conditions of this strategy to achieve good accuracy and precision. Compared with existing magnetic solid phase extraction methods for NTs detection in biological samples, this strategy could adsorb more targets while having similar adsorption efficiencies, and the total process time was reduced by an average of 69.42%. We rapidly determined the metabolic abnormality of 6 types of NTs in the serum of PD patients and demonstrated their diagnostic accuracy. In addition, an outstanding feature of PD in which tryptophan was more metabolized by the KYN pathway and the 5-hydroxytryptamine pathway was inhibited could be elucidated by this strategy. Our results highlighted the potential ability of Fe3O4@PDA coupled with DART-MS to assist in the clinical diagnosis of PD.

关键词： neurotransmitters panic disorder magnetic solid phase extraction direct analysis of mass spectrometry in real time

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五边形石墨烯氧气吸附与解离特性研究

原子与分子物理学报 2025年第4期42卷 40-44页

作者：吴旌贺丁雅妮郭梦雨陈卫光史金磊河南财政金融学院创新创业学院郑州450046 郑州师范学院物理与电子工程学院郑州市低维纳米材料重点实验室郑州450044

基于密度泛函理论的第一性原理计算方法,研究了O_(2)在五边形石墨烯(PG)上的吸附与解离动力学行为.研究结果表明,PG并不能有效地激发O_(2),形成稳定的氧吸附结构需要克服约0.54 eV势垒,并且吸附的O_(2)分解需要克服约0.82 eV势垒.然而,O... 详细信息

基于密度泛函理论的第一性原理计算方法,研究了O_(2)在五边形石墨烯(PG)上的吸附与解离动力学行为.研究结果表明,PG并不能有效地激发O_(2),形成稳定的氧吸附结构需要克服约0.54 eV势垒,并且吸附的O_(2)分解需要克服约0.82 eV势垒.然而,O_(2)分解后的PG衬底结构却能使后续吸附的O_(2)分子自动分解,破坏C-C键,以致PG在空气中难以稳定存在.基于此,为了避免PG结构在空气中被氧化,我们进一步提出将过渡金属原子吸附PG,使得O_(2)更容易被过渡金属原子吸附与激发,从而避免了PG被氧化.

关键词：五边形石墨烯 O_(2)吸附与解离第一性原理计算

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Reaction between Ti–6Al–4V and Y_2O_3–SiO_2 based face shell for investment casting

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Rare Metals 2016年第12期35卷 901-908页

作者： ya-Meng wei Zhi-Gang Lu Guang-Peng wu Xing-Quan Long Department of Mechanical Engineering Tsinghua University State Key Laboratory of Tribology Tsinghua University Guizhou Anji Aviation Investment Casting Co. Ltd.

The pH value and viscosity of Y2O3-SiO2 （Y-Si） slurry made by Y2O3 powders and silica sol for the face coat of Ti-6Al-4V investment casting were measured. The thermal behavior of the shell made by the Y-Si face coat system was investigated by differential scanning calorimeter （DSC）, thermal gravimetric （TG） analysis combined with mass spectrometry （MS）, and the phase transformations were determined by X-ray diffraction （XRD）. Hot strength, residual strength, linear expansion coefficient, and wearing resistance performance of the shell were also tested. The microstructure and elements distri- bution of the interaction layer were studied by scanning electron microscope （SEM） and energy-dispersive spectrometer （EDS）, respectively. The microhardness tester was applied for the microhardness. The results showed that the slurry was stable for at least 60 h. A very small amount of YZrO3 was formed below 1050℃ and Y2SiO5 was formed around 1450℃. The shell made by Y-Si system had good mechanical property which could reduce cracks during the procedure of dewaxing and inclusions during pouring. Some Al volatilized from the melt, permeated the surface of the face coat shell, and formed the black reaction layer, which blocked the permeation of O so that O penetration was limited to 5μm. The depth of Si penetration was about 60 μm. The hard layer was also around 60 μm.

关键词： Investment casting Titanium alloy Silica sol Yttrium oxide Interface reaction

CO2-mediated bicarbonate conversion to concentrated formate in a CEM-based electrolyzer

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Journal of Energy Chemistry 2025年第1期100卷 605-611页

作者： Haocheng Xiong Donghuan wu Haonan Li Andrew Li Qikun Hu Siyao Song Bingjun Xu Qi Lu State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University College of Chemistry and Molecular Engineering Peking University Ordos Laboratory

Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO2emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO2using alkaline solutions with reactive *** this work,we present a CO2-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm2electrode *** electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended *** techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.

关键词： Electrocatalysis Techno-economic assessments Electrochemistry Flow electrolyzer

Exothermic process of cast-in-place pile foundation and its thermal agitation of the frozen ground under a long dry bridge on the Qinghai-Tibet Railway

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 88-96页

作者： ya-ping wu Jian GUO Chun-xiang GUO wei MA Xiao-jun WANG School of Civil and Arehiteeture Engineering Ningbo Institute of Technology Zhejiang University Ningbo 315100 China School of Civil Engineering Lanzhou Jiaotong University Lanzhou 730070 China State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environment and Engineering Research Institute Chinese Aeademy of Sciences Lanzhou 730000 China

A number of dry bridges have been built to substitute for the roadbed on the Qinghai-Tibet Railway,*** aim of this study was to investigate the exothermic process of cast-in-place (CIP) pile foundation of a dry bridge and its harm to the stability of nearby frozen *** present 3D heat conduction functions of a concrete pile and of frozen ground with related *** analysis is based on the theory of heat conduction and the exponent law describing the adiabatic temperature rise caused by hydration *** under continuous and initial conditions were combined to establish a finite element model of a CIP pile-frozen ground system for a dry bridge under actual field conditions in cold *** results indicated that the process could effectively simulate the exothermic process of CIP pile *** disturbance to frozen ground under a long dry bridge caused by the casting temperature and hydration heat of CIP piles was substantial and *** simulated thermal analysis results agreed with field measurements and some significant rules relating to the problem were deduced and conclusions reached.

关键词： Exothermic process of hydration heat Cast-in-place (CIP) pile foundation Dry bridge Thermal agitation Frozen ground Qinghai-Tibet Railway

Effect of Heat Treatment Process on Properties of 1000 MPa Ultra-High Strength Steel

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Journal of Iron and Steel Research International 2011年第2期18卷 64-69页

作者： YU wei QIAN ya-jun wu Hui-bin yaNG Yue-hui Metallurgical Engineering Institute University of Science and Technology Beijing Beijing 100083 China

Two types of steel, C-Mn-CrMo B microalloyed steel and C-Mn-Mo-Nb-Cu-B microalloyed steel, are designed to develop 1000 MPa ultra high strength steel. Two kinds of processes, thermomeehanical controlled process （TMCP） combined with traditional off-line quenching and tempering （QT） process versus controlled rolling process （CR） combined with direct quenching and tempering （DQ＋T） process, are applied. The effect of heat treatment processing mode on the microstructure and mechanical properties is studied. The relationship between microstructure and mechanical properties is investigated by SEM and TEM. After tempering at 450 to 550 ℃ for 1 h, the steel produced by TMCP＋QT process shows combination of excellent strength and low temperature toughness. The yield strength is above 1 000 MPa, elongation above 15% and impact energy at -40 ℃ more than 30 J. After tempering at 450 ℃, a large number of ε-Cu particles precipitated in C-Mn-Mo-Nb-Cu-B steel produced by CR＋DQ＋T process lead to a significant increase in yield strength. And after tempering at 500 to 600 ℃, the yield strength of the steel is further improved to 1 030 MPa because of precipitates, such as nitride or carbide of niobium, carbide of molybedenum and vanadium. When the tempering temperature is increased above 620 ℃, the yield strength is still higher than 1 000 MPa and elongation is above 20% and impact energy at --40 ℃ is more than 35 J. After tempering at above 500 ℃, the toughness of the steel treated by TMCP＋QT process is superior to that of steel by CR＋DQ＋T process.

关键词： heat treatment high strength steel microstructure mechanical property

Variant selection of nanocrystalline a phase in metastableβTB8 titanium alloy via electric pulse treatment

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Rare Metals 2023年第8期42卷 2781-2794页

作者： Shan-Shan wu ya yang Yuan-Biao Tan Song Xiang ya-Li Zhou Min Ma Fei Zhao wei Shi Guizhou Key Laboratory of Materials Mechanical Behavior and Microstructure College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China College of Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

In this paper,the metastableβTB8 titanium alloy with nanocrystallineαphase is achieved by electric pulse *** morphology evolution and variant selection of nanocrystallineαphase in metastableβTB8titanium alloy were investigated by using scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscope(TEM)*** results indicated that the morphologies of the nanocrystallineαphase were mainly triangular clusters and needle-like at the pressure of 0 *** increasing pressure from 20 to 50 MPa,the volume fraction of needlelikeαphase decreased,and a large amount of V-shapedαphase formed in the interior ofβ*** on the EBSD data,the parentβphase was reconstructed by MTEX *** the interior of theβgrains,12 variants can form for the samples electric pulse treated at 0 and20 MPa,while only 3 and 6 variants can form for the samples electric pulse treated at 30 and 50 *** the grain boundary of theβgrains,one or more grain boundaryαvariants can be generated for the samples electric pulse treated at different pressures as long as one of the neighborβgrains follows the Burgers orientation relationship.

关键词： TB8 titanium alloy Parentβgrain reconstruction Morphology ofαphase Variant selection

Ratiometric and selective two-photon fluorescent probe based on PET-ICT for imaging Zn^(2+)in living cells and tissues

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Chinese Chemical Letters 2014年第1期25卷 93-98页

作者： Shang wu ya-Jun wei yan-Bin Wang Qiong Su Lan wu Hong Zhang Fen-Ping Yin Pei-Lin Yuan College of Chemical EngineeringNorthwest University for Nationalities

A two-photon fluorescent probe TPZn was developed for specific ratiometric imaging Zn2＋ in living cells and tissues. Significant ratiometric fluorescence change was based on photoinduced electron transfer and intramolecular charge transfer. The synthetic method of TPZn was simple. It was successfully used to selectively image Zn2＋ based on the higher binding affinity for Zn2＋ than for Cd2＋. TPZn was easily loaded into the living cell and tissues with high membrane permeability in a complex biological environment. TPZn could clearly visualize endogenous Zn2＋ by TP ratiometric imaging in hippocampal slices at a depth of 120 μm. Thus, TPZn is a useful tool to image of Zn2＋ in living cells and tissues without interference from Cd2＋.

关键词： Two-photon probe Ratiometric fluorescent imaging ZincLiving cell Living tissue