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A novel synthesis of 5-aryl-3-cyano-2-pyridones by using vinamidinium salts

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Chinese Chemical Letters 2009年第7期20卷 771-774页

作者： Xue Hui zhang wu zhong Xing Zhou Li Song Li Beijing Institute of Pharmacology and Toxicology Beijing 100850 China

A variety of vinamidinium salts were condensated with cyanoacetamide in refluxing methanol that contained sodium methoxide to produce 5-aryl-3-cyano-2-pyridones in good yield. Simple experimental conditions were used to prepare ten different 5-aryl-3- cyano-2-pyridones, four of which are new compounds.C 2009 Song Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 5-Aryl-3-cyano-2-pyridones Vinamidinium salts Cyclization

Enhanced visible light absorption of Bi_(2)WO_(6)/SiO_(2) with abundant adsorbed oxygen for the degradation of organic pollutant

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Particuology 2024年第5期88卷 210-217页

作者： Yuanting wu Xiaoying Wang Wenlong zhong Shan zhang School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China

Heterogeneous photocatalysts exhibit high catalytic efficiency in the degradation of pollutants,but their stability and repeatability is not very good and requires high structural *** by nanosizing the pure Bi_(2)WO_(6)(BWO)photocatalyst without constructing a heterojunction,there is a significant improvement in its performance,with an enhancement effect of about 2.3 times(99.43%).The high photocatalytic degradation efficiency of the material can be attributed to the enhanced light absorption effect brought by the three-dimensional inverse-opal structure SiO_(2)(IS)and the abundant surface adsorbed oxygen generated after the formation of Si–O–W *** addition,the introduction of IS greatly increases the surface area of nanostructured BWO,which accelerates the charge transfer process,while the adsorbed oxygen promotes the participation of·O^(2−) in the photocatalytic reaction,thereby accelerating the consumption of photo-generated electrons and ultimately improving the separation of charge ***,the matched photonic bandgap further improves the absorption and utilization of light of the *** this work,we constructs Si–O–W bonds to obtain inverse-opal SiO_(2)/Bi_(2)WO_(6) with uniformly growth of pure phase nano BWO,which provides a feasible strategy for the preparation of high-performance pure-phase photocatalysts.

关键词： Bi_(2)WO_(6) SiO_(2) inverse-opal structure Photocatalysis Adsorbed oxygen

Optical detection method of discharge mode transition of inductively coupled plasma in an atmosphere-breathing electric propulsion system

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Chinese Journal of Aeronautics 2024年第10期37卷 172-183页

作者： Yuxuan zhong Yu zhang Jianjun wu Peng ZHENG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Plasma discharge stability is an important problem in atmosphere-breathing electric propulsion system when maintaining long-term missions at ultra-low earth *** paper designed an inductively coupled plasma source to imitate the ionization *** effect of inflow rate and Radio Frequency(RF)power on the plasma discharge mode transition is experimentally studied.A discharge mode detection method is proposed,which determines the discharge mode by identifying the morphology of the plasma *** using the method,the discharge mode transition is quantified and a control model based on the parameter sensitivity is *** verify the method,the spectra are measured and the electron temperature spatial distribution is *** the method has been proven *** results show that the inductively coupled discharge contains capacitive components affected by the mass flow rate and the radio frequency *** plasma characteristics can be maintained stably by controlling the radio frequency power when the mass flow rate randomly changes in a certain *** is demonstrated that the application of detection method effectively identifies the discharge mode,which is a promising active control method for the plasma discharge mode.

关键词： Atmosphere-breathing electric propulsion Inductively coupled plasma Discharge mode transition Optical diagnosis Ultra-low earth orbit

Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics

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Journal of Integrative Agriculture 2024年第3期23卷 876-887页

作者： Liyao Su Min wu Tian zhang Yan zhong Zongming(Max) Cheng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing210095China

Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii.

关键词： Rosa roxburghii quercetin derivatives weighted gene co-expression network analysis transcription factor transcriptome metabolome

High-Voltage and Fast-Charging Lithium Cobalt Oxide Cathodes: From Key Challenges and Strategies to Future Perspectives

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Engineering 2024年第6期37卷 105-127页

作者： Gongrui Wang Zhihong Bi Anping zhang Pratteek Das Hu Lin zhong-Shuai wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China

Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable ***,the lithium ion(Li+)-storage performance of the most commercialized lithium cobalt oxide(LiCoO_(2),LCO)cathodes is still far from satisfactory in terms of high-voltage and fast-charging capabilities for reaching the double-high ***,we systematically summarize and discuss high-voltage and fast-charging LCO cathodes,covering in depth the key fundamental challenges,latest advancements in modification strategies,and future perspectives in this *** and elaborated discussions are first presented on key fundamental challenges related to structural degradation,interfacial instability,the inhomogeneity reactions,and sluggish interfacial *** provide an instructive summary of deep insights into promising modification strategies and underlying mechanisms,categorized into element doping(Li-site,cobalt-/oxygen-site,and multi-site doping)for improved Li+diffusivity and bulkstructure stability;surface coating(dielectrics,ionic/electronic conductors,and their combination)for surface stability and conductivity;nanosizing;combinations of these strategies;and other strategies(i.e.,optimization of the electrolyte,binder,tortuosity of electrodes,charging protocols,and prelithiation methods).Finally,forward-looking perspectives and promising directions are sketched out and insightfully elucidated,providing constructive suggestions and instructions for designing and realizing high-voltage and fast-charging LCO cathodes for next-generation double-high LIBs.

关键词： Lithium cobalt oxide High energy/power density Fast-charging High-voltage Lithium-ion battery

Collaborative robust dispatch of electricity and carbon under carbon allowance trading market

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Global Energy Interconnection 2024年第4期7卷 391-401页

作者： Songyu wu Xiaoyan Qi Xiang Li Xuanyu Liu Bolin Tong Feiyu zhang zhong zhang Electric Power Research Institute of State Grid Liaoning Electric Power Co. Shenyang 110006P.R.China School of Electrical Engineering Dalian University of TechnologyDalian 116024P.R.China

The launch of the carbon-allowance trading market has changed the cost structure of the power *** is an asynchronous coupling mechanism between the carbon-allowance-trading market and the day-ahead power-system *** this study,a data-driven model of the uncertainty in the annual carbon price was ***,a collaborative,robust dispatch model was constructed considering the annual uncertainty of the carbon price and the daily uncertainty of renewable-energy *** model is solved using the column-and-constraint generation *** operation and cost model of a carbon-capture power plant(CCPP)that couples the carbon market and the economic operation of the power system is also *** critical,profitable conditions for the economic operation of the CCPP were *** studies demonstrated that the proposed low-carbon,robust dispatch model reduced carbon emissions by 2.67%compared with the traditional,economic,dispatch *** total fuel cost of generation decreases with decreasing,conservative,carbon-price-uncertainty levels,while total carbon emissions continue to *** the carbon-quota coefficient decreases,the system dispatch tends to increase low-carbon unit *** study can provide important guidance for carbon-market design and the low-carbon-dispatch selection strategies.

关键词： Asynchronous coupling mechanism Collaborative robust optimization Carbon price uncertainty Carbon capture power plant Low carbon dispatch

Advances in methane emissions from agricultural sources:Part *** and mitigation

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Journal of Environmental Sciences 2024年第6期140卷 279-291页

作者： Xiaokun wu Ying zhang Yinghui Han Yagang zhang Yuhang zhang Xiaodan Cheng Pei zhong Xue Yuan Yuanxun zhang Zhengqiang Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071003China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Interdisciplinary Mathematics Institute University of South CarolinaColumbiaSC 29208United States Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

Methane is one of the major greenhouse gases(GHGs)and agriculture is recognized as its primary *** accounting is a prerequisite for developing effective agriculture mitigation *** this review,methane accounting methods and research status for various agricultural emission source including rice fields,animal enteric fermentation and livestock and poultry manure management were overview,and the influencing factors of each emission source were analyzed and *** the same time,it analyzes the different research efforts involving agricultural methane accounting and makes recommendations based on the actual ***,mitigation strategies based on accounting results and actual situation are *** review aims to provide basic data and reference for agriculture-oriented countries and regions to actively participate in climate action and carry out effective methane emission mitigation.

关键词： Methane emission Agricultural sources Accounting methodology Mitigation Emission influencing factors

Hybrid ion/electron interfacial regulation stabilizes the cobalt/oxygen redox of ultrahigh-voltage lithium cobalt oxide for fast-charging cyclability

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Science Bulletin 2024年第13期69卷 2071-2079页

作者： Zhihong Bi Anping zhang Gongrui Wang Cong Dong Pratteek Das Xiaoyu Shi zhong-Shuai wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory of Clean Energy Chinese Academy of SciencesDalian 116023China

High-voltage and fast-charging LiCoO_(2)(LCO)is key to high-energy/power-density Li-ion ***,unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-charging ***,we construct a Li/Na-B-Mg-Si-O-F-rich mixed ion/electron interface network on the 4.65 V LCO electrode to enhance its rate capability and long-term cycling ***,the resulting artificial hybrid conductive network enhances the reversible conversion of Co^(3+)/^(4+)/O_(2)/nredox by the interfacial ion–electron cooperation and suppresses interface side reactions,inducing an ultrathin yet compact cathode electrolyte ***,the derived near-surface Na+/Mg2+/Si^(4+)-pillared local intercalation structure greatly promotes the Li^(+)diffusion around the 4.55 V phase transition and stabilizes the cathode ***,excellent 3 C(1 C=274 mA g1)fast charging performance is demonstrated with 73.8%capacity retention over 1000 *** findings shed new insights to the fundamental mechanism of interfacial ion/electron synergy in stabilizing and enhancing fast-charging cathode materials.

关键词： High-voltage Fast-charging LiCoO_(2) Interfacial ion-electron cooperation Local intercalation

Recent advances and key perspectives of in-situ studies for oxygen evolution reaction in water electrolysis

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Green Energy & Environment 2024年第10期9卷 1497-1517页

作者： Yi Wang Zichen Xu Xianhong wu zhong-Shuai wu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Shijingshan District Dalian National Laboratory for Clean Energy Chinese Academy of Sciences

Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems, in which the anodic oxygen evolution reaction(OER) is the key half-reaction of performance-limiting in water splitting. Given the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions, unraveling the real active sites, probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are essential. In this review, we summarize the recent advancements in understanding the catalytic process, unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization techniques. Firstly, we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER, and highlight the significance of optimal catalytic pathways and intrinsic stability. Next, we provide a comprehensive overview of the fundamental working principles,different detection modes, applicable scenarios, and limitations associated with the in-situ characterization techniques. Further, we exemplified the in-situ studies and discussed phase transition detection, visualization of speciation evolution, electronic structure tracking, observation of reaction active intermediates, and monitoring of catalytic products, as well as establishing catalytic structure–activity relationships and catalytic mechanism. Finally, the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed.

关键词： In-situ studies Water splitting Oxygen evolution reaction Catalytic mechanism