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A New Method for the Aging Evaluation of Oil-Paper Insulation Using η-Butanol and methanol

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 717-726页

作者： Jianyi Wang Yuanxiang Zhou Jun Liu Zhaowei Wang Song Bai Jiayu Lu Department of High Voltage China Electric Power Research InstituteBeijing 100192China State Key Laboratory of Power Grid Environmental Protection Beijing 100192China Electrical Engineering Department Tsinghua UniversityBeijing 100084China Solar Storage Division of State Key Lab of Power System and Generation Equipment School of Electrical EngineeringXinjiang UniversityUrumqi 830047China State Grid Wuwei Electric Power Supply Company Wuwei 733000China

To improve the accuracy and efficiency of the aging life prediction and assessment of transformer oil-paper insulation,and to make up for the deficiencies of traditional characterizers,such as 2-furfural,carbon monoxide,and carbon dioxide,a method for the simultaneous determination of methanol,ethanol,n−propanol,and η-butanol in oil with a single injection is established by headspace-gas chromatography-mass spectrometry.The measured results show that the determination limits of the four alcohol characterizers can be controlled to 10μg/kg level.Based on this method,the change patterns of the above four alcohols with thermal aging time and degree of polymerization are obtained through thermal aging experimental research.Ethanol,η-propanol,and η-butanol in oil indicate nearly linear correlations with thermal aging time and degree of polymerization,similar to that of methanol.By analyzing 52 sets of measured data of 500 kV EHV transformers in operation,η-butanol is found to have excellent performance,and a new method to evaluate the aging state of oil-paper insulation employing η-butanol and methanol is proposed along with the aging attention value model.The measured data of 500 kV EHV transformers in operation indicate that the combination of η-butanol and methanol as the preferred characterizers can effectively compensate for the shortcoming of traditional characterizers in the early stages of aging,and the feasibility of the method is verified.Two possible pathways for the generation of η-butanol by cellulose cleavage during the aging of oil-paper are proposed from the chemical structure of cellulose.

关键词： Aging characterization determination method methanol η-butanol oil-paper insulation 500 kV transformers

The origins of catalytic selectivity for the electrochemical conversion of carbon dioxide to methanol

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Nano Research 2024年第1期17卷 5-17页

作者： Tian Wang Yating Wang Yuhang Li Chunzhong Li Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Materials Science and EngineeringEast China University of Science&TechnologyShanghai 200237China School of Chemical Engineering East China University of Science&TechnologyShanghai 200237China

The electrocatalytic conversion of carbon dioxide(CO_(2))into useful fuels and chemical feedstocks is an emerging route to alleviate global warming and reduce reliance on fossil fuels.methanol(CH_(3)OH),as one of the most significant and widely used liquid fuels that can be generated by CO_(2)reduction,is essential in the chemical industry.In this minireview,we unravel the origins of the selective formation of CH_(3)OH via CO_(2)reduction,including catalyst composition designs,local structure modulations,and electrolyte/catalyst interface regulations.Finally,the remaining challenges and perspectives for the CO_(2)-to-CH_(3)OH reduction are proposed.

关键词： methanol carbon dioxide(CO_(2))reduction reaction electrochemistry electrocatalyst catalyst-electrolyte interface

Effect of reduction pretreatment on the structure and catalytic performance of Ir-In_(2)O_(3)catalysts for CO_(2) hydrogenation to methanol

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Journal of Environmental Sciences 2024年第6期140卷 2-11页

作者： Changyu Ding Feifei Yang Xue Ye Chongya Yang Xiaoyan Liu Yuanlong Tan Zheng Shen Hongmin Duan Xiong Su Yanqiang Huang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this reaction.However,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to methanol.In the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction temperatures.The CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the activity.By finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption cycle.Higher performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.

关键词： Carbon dioxide Hydrogenation methanol In_(2)O_(3) Fixed-bed Reduction temperature

CO_(2) hydrogenation to methanol over the copper promoted In_(2)O_(3) catalyst

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Journal of Energy Chemistry 2024年第6期93卷 135-145,I0004页

作者： Rui Zou Chenyang Shen Kaihang Sun Xinbin Ma Zhuoshi Li Maoshuai Li Chang-Jun Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science&Engineering Tianjin UniversityTianjin 300072China

The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) catalyst.The loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active site.The Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol selectivity.With increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.

关键词： CO_(2)hydrogenation methanol Cu In_(2)O_(3) CO Selectivity DFT

Photocatalytic oxidation of methane to methanol over zinc titanate supported silver catalysts

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Journal of Rare Earths 2024年第5期42卷 899-906,I0004页

作者： Yuyan Gan Jinbi Huang Qian Lv Yanru Li Lizhi Wu YU Tang Yuanxing Fang Pengfei Zhu Li Tan Institute of Molecule Catalysis and In-Situ/Operando Studies State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350108China School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'an 70021China

The direct activation of methane under mild condition to achieve highly selective of oxygenates is a challenging project.In this study,a well dispersed silver supported ZnTiO_(3) catalyst was prepared to achieve selective preparation of methanol from methane and water under mild condition.X-ray diffraction,transmission electron microscopy and X-ray photoelectron spectroscopy characterizations demonstrate that silver species are uniformly dispersed on ZnTiO_(3) surface in the form of metallic silver nanoparticles.The photoelectric characterizations reveal that the addition of silver species enhances light absorption and promotes charge separation of the catalysts.Under the reaction conditions of 50℃and 3 MPa,the methanol is obtained as the only liquid product over the designed Ag/ZnTiO_(3) catalyst under light irradiation.In this photocatalytic process,the holes generated by ZnTiO_(3) activate water to produce intermediate·OH,which further reacts with methane to synthesize methanol.The silver species as co-catalysts extend the light absorption range of ZnTiO_(3) as well as promote charge separation.

关键词： Photocatalytic Methane oxidation Zinc titanate Silver methanol

Sensing properties and mechanisms of LaF3–Co3O4nanorods for low-concentration methanol detection

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Rare Metals 2024年第5期43卷 2193-2204页

作者： Xiao-Xi He Hong-Feng Chai Yi-Wen Zhou Ke-Wei Liu Ze-Xin Yu Chao Zhang College of Mechanical Engineering Yangzhou University Institute for Manufacturing Technologies of Ceramic Components and Composites (IMTCCC) University of Stuttgart

methanol is one of the characteristic gases that distinguish between healthy individuals and lung cancer（LC） lesions in exhaled human breath.Its concentration in exhaled breath is generally below one part per million(1×10-6).The second-phase composite is widely regarded as one of the methods to improve the gas-sensing performance of metal oxide semiconductor （MOS） materials.In this study,LaF3DCo3O4was synthesized by a simple hydrothermal method to enhance its low-concentration methanol gas-sensing performance.5 at%LaF3DCo3O4nanorods exhibited excellent methanol detection performance,including a wider linear detection concentration range (0.2×10-6D5×10-6),a response value exceeding 4.0for 1×10-6methanol at 275°C and 75%relative humidity（RH）,long-term stability （maximum deviation within 15%over 2 weeks）,and excellent selectivity.The mechanism of performance enhancement was studied using various techniques,and density functional theory.The specia spinel structure of Co3O4,the high ionic migration of F-in LaF3,the larger specific surface area of 5 at%LaF3DCo3O4nanorods,and the generated crystal defects all explain the excellent methanol gas-sensing property.This work provides a novel route to prepare MOS composite materials for low-concentration methanol gas detection.

关键词： Gas sensor LaF 3 Co 3 O 4 methanol Lung cancer

A new perspective on hydrogenation of CO2 into methanol over heterogeneous catalysts

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Progress in Natural Science:Materials International 2024年第3期34卷 482-494页

作者： Xueyuan Pan Jingcheng Xu Yali Wang Mingzhe Ma Haiquan Liao Hao Sun Mengmeng Fan Kui Wang Kang Sun Jianchun Jiang Key Lab.of Biomass Energy and Material Jiangsu Province Key and Open Lab.of Forest Chemical Engineering SFA National Engineering Lab.for Biomass Chemical Utilization Institute of Chemical Industry of Forest Products Chinese Academy of Forestry Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry University

The utilization of carbon dioxide is critical to realize the objective of "carbon peak and neutrality". Among various carbon dioxide exploitation approaches, catalytic hydrogenation of carbon dioxide is a significant method to selectively convert the CO2into methanol and other valuable chemicals. Among these products, methanol is a crucial chemical feedstock that can be utilized as a platform molecule for the synthesis of chemicals and fuels as well as a fuel for internal combustion engines and fuel cells, causing particular interest. Nowadays, Catalytic hydrogenation of carbon dioxide into methanol has shifted its focus on the creation of low-cost, environmentally friendly, and efficient catalysts. Inspired of this, we have concluded the mechanism of catalytic hydrogenation of carbon dioxide, and reviewed the research progress of multiple heterogeneous catalysts with high catalytic application prospect, especially the supported catalysts.

关键词： Carbon dioxide Heterogeneous catalyst Hydrogenation methanol

High-density triple-phase contact points for enhanced photocatalytic CO_(2) reduction to methanol

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Chinese Chemical Letters 2024年第2期35卷 252-256页

作者： Hanwen Jian Kaiming Deng Tongyu Wang Chengxi Huang Fang Wu Hailing Huo Bo Ouyang Xuan Liu Jingjing Ma Erjun Kan Ang Li MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of ScienceNanjing University of Science and TechnologyNanjing 210094China College of Information Science and Technology Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

The efficiency of photocatalytic CO_(2) reduction reaction(PCRR)is restricted by the low solubility and mobility of CO_(2) in water,poor CO_(2) adsorption capacity of catalyst,and competition with hydrogen evolution reaction(HER).Recently,hydrophobic modification of the catalyst surface has been proposed as a potential solution to induce the formation of triple-phase contact points(TPCPs)of CO_(2)(gas phase),H_(2) O(liquid phase),and catalysts(solid phase)near the surface of the catalyst,enabling direct delivery of highly concentrated CO_(2) molecules to the active reaction sites,resulting in higher CO_(2) and lower H+surface concentrations.The TPCPs thus act as the ideal reaction points with enhanced PCRR and suppressed HER.However,the initial synthesis of triple-phase photocatalysts tends to possess a lower bulk density of TPCPs due to the simple structure leading to limited active points and CO_(2) adsorption sites.Here,based on constructing a hydrophobic hierarchical porous TiO_(2)(o-HPT)with interconnected macropores and mesopores structure,we have significantly increased the density of TPCPs in a unit volume of the photocatalyst.Compared with hydrophobic macroporous TiO_(2)(o-MacPT)or mesoporous TiO_(2)(o-MesPT),the o-HPT with increased TPCP density leads to enhanced photoactivity,enabling a high methanol production rate with 1111.5μmol g^(−1) h^(−1) from PCRR.These results emphasize the significance of high-density TPCPs design and propose a potential path for developing efficient PCRR systems.

关键词： Photocatalysis CO_(2)reduction reaction Photocatalyst Triple-phase contact points methanol

High-speed impulsive stimulated Brillouin microscopy

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Photonics Research 2024年第4期12卷 730-739页

作者： JIARUI LI TAORAN LE HONGYUAN ZHANG HAOYUN WEI YAN LI State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Cole Eye Institute Cleveland ClinicClevelandOhio 44195USA

Brillouin microscopy, which maps the elastic modulus from the frequency shift of scattered light, has evolved to a faster speed for the investigation of rapid biomechanical changes. Impulsive stimulated Brillouin scattering (ISBS)spectroscopy has the potential to speed up measurement through the resonant amplification interaction from pulsed excitation and time-domain continuous detection. However, significant progress has not been achieved due to the limitation in signal-to-noise ratio (SNR) and the corresponding need for excessive averaging to maintain high spectral precision. Moreover, the limited spatial resolution also hinders its application in mechanical imaging. Here, by scrutinizing the SNR model, we design a high-speed ISBS microscope through multi-parameter optimization including phase, reference power, and acquisition time. Leveraging this, with the further assistance of the Matrix Pencil method for data processing, three-dimensional mechanical images are mapped under multiple contrast mechanisms for a millimeter-scale polydimethylsiloxane pattern immersed in methanol, enabling the identification of these two transparent materials without any contact or labeling. Our experimental results demonstrate the capability to maintain high spectral precision and resolution at a sub-millisecond integration time for one pixel. With a two-order improvement in the speed and a tenfold improvement in the spatial resolution over the state-of-the-art systems, this method makes it possible for ISBS microscopes to sensitively investigate rapid mechanical changes in time and space.

关键词： Brillouin maintain methanol