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Elucidating solvent effects on the stability of phenoxyl radicals in monohydric alcohols via electron paramagnetic resonance

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Green Chemical Engineering 2024年第4期5卷 483-488页

作者： Xinyu wang Wenjing Sun yongtao wang Haoran Li Department of Chemistry Zhejiang UniversityHangzhou310058China Center of Chemistry for Frontier Technologies ZJU-NHU United R&D CenterZhejiang UniversityHangzhou310058China State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China

Research on solvent effects is an important and long-standing topic,but there still is some room,especially for the special solvent effect of *** this work,we investigated the stability of phenoxyl radical in monohydric alcohol solvents through in-situ electron paramagnetic resonance *** decay behavior of phenoxyl radical showed a reasonable relationship with the mesoscopic structure of alcohols,characterized by smalland wide-angle X-ray ***,the distinct solvent effects of fluoroalcohols were emphasized,and the significant influence of van der Waals distance in the solvents was ***,the stability of phenoxyl radical in alcohols was quantified and correlated with the solvent *** believe that the established method for stability study on radicals will encourage solvent effect studies on various organic reactions,and the proposed solvent effects in fluoroalcohols may inspire the development of green solvents in both industrial conversions and organic synthesis.

关键词： Solvent effect Fluoroalcohol Phenoxyl radical Stability Electron paramagnetic resonance

Receiver Detection Employing Semaphore in Cognitive Radio

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China Communications 2010年第1期7卷 41-49页

作者： wang Weidong Li Fan Zhang Yinghai wang Shoufeng wang yongtao Beijing Jiaotong Univ Natl Engn Lab Next Generat Internet Interconnect Beijing 100044 Peoples R China

Interference from secondary users to primary users should be avoided in cognitive radio. However, it is difficult to solve the interference problem if the secondary users cannot get the information of the primary receivers. Insufficient information of primary users would result in inaccurate spectrum detecting result. To deliver the information of primary users, Receiver Detection Employing Semaphore (ReDES) is proposed in this paper. Primary receiver informs secondary users of its licensed receive frequency according to semaphore architecture directly in ReDES. The semaphore is used to determine the spectrum holes by secondary users. Frequency mapping method is come up with as a realization of ReDES. The procedure and the detailed techniques are illustrated to make ReDES scheme reasonable and feasible. Simulation results show that the proposed scheme can effectively detect the frequencies of primary receivers, and improve the accuracy of spectrum detection.

关键词： cognitive radio receiver detection hidden terminal problem.

高静压联合天然抑制剂处理对浑浊苹果汁多酚氧化酶活性及相关品质的影响

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食品科学 2025年第2期46卷 1-7页

作者：田学智曹智鸿江乃相肖志剑唐征王永涛中国农业大学食品科学与营养工程学院国家果蔬加工工程技术研究中心农业农村部果蔬加工重点实验室食品非热加工北京市重点实验室北京100083 山东泰乐源农业科技有限公司山东泰安271411

探究高静压(high hydrostatic pressure,HHP)联合阿魏酸(ferulic acid,FA)、表没食子儿茶素没食子酸酯(epigallocatechin gallate,EGCG)处理对浑浊苹果汁中多酚氧化酶(polyphenol oxidase,PPO)活性及相关品质的影响。结果表明,添加0.1 g/100 mL的FA或者0.2 g/100 mL的EGCG均能显著降低样品中PPO活性,并显著提高其亮度(P<0.05)。单独HHP处理(550 MPa、5 min)样品的PPO相对残余活性高达82.70%,而经过HHP+FA或HHP+EGCG处理后,样品的PPO相对残余活性分别降至66.35%和41.50%。在冷藏2周期间,样品的PPO活性持续下降,而颜色参数保持稳定。贮藏第14天,HHP+FA组的褐变指数最小,仅有4.37,而HHP+EGCG组的PPO相对残余活性最低(24.71%)。此外,两组样品都保留了80%以上的总酚和90%以上的抗氧化能力。综上,HHP与FA/EGCG的联合处理可以有效抑制浑浊苹果汁的酶促褐变,具有进一步推广应用的潜力。

关键词：高静压天然抑制剂浑浊苹果汁多酚氧化酶品质

Health effects of fruit juices and beverages with varying degrees of processing

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Food Science and Human Wellness 2024年第5期13卷 2456-2479页

作者： Xinyue Zhang Xiaojun Liao yongtao wang Lei Rao Liang Zhao National Engineering Research Center for Fruit and Vegetable Processing Key Laboratory of Fruit and Vegetable ProcessingKey Laboratory of Food Non-Thermal ProcessingMinistry of Agricultural and Rural AffairsCollege of Food Science&Nutritional EngineeringChina Agricultural UniversityBeijing 100083China

The degree of processing is rarely considered an independent factor in the health effects of fruit juices and beverages(FJBs)*** fact,the consumption of ultra-processed foods has been shown to pose health *** this study,we first integrated 4 systems used to classify the degree of food processing and then classified FJBs into three major categories,low(minimal),moderate and ***,we compared the differences in attitudes towards FJBs in dietary ***,we integrated the results of existing epidemiological surveys,randomized controlled trials,and animal experiments to explore the health risks associated with consuming *** the processing of FJBs has been found to lead to an increased risk of *** pattern,nutrients,addition agents and consumer preferences may be influential ***,we investigated whether there were any changes in the health benefits of 100%fruit juices produced by different processing *** conclusion,minimally/moderately processed 100%fruit juices provide more health benefits than highly processed fruit *** results support the need to consider the extent of FJBs processing in future studies to adjust official nutritional recommendations for beverage consumption.

关键词： Fruit juices and beverages Dietary guidelines Degree of processing Health effects Mechanism

Wide-pH-range adaptable ammonia electrosynthesis from nitrate on Cu-Pd interfaces

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Science China Chemistry 2023年第3期66卷 913-922页

作者： yongtao wang Peng Zhang Xiaoyun Lin Gong Zhang Hui Gao Qingzhen wang Zhi-Jian Zhao Tuo wang Jinlong Gong Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

Ammonia production via electrochemical nitrate reduction is essential for environmental protection and the emerging hydrogen economy. Complex nitrate wastewater with a wide pH range calls for flexible catalysts with high selectivity. A high Faradaic efficiency(FE) of NH3 cannot be obtained under strong acid or alkaline conditions due to the uncontrollable adsorption energy and coverage of hydrogen species(H*) on active sites. This article describes the design and fabrication of a copper-palladium(Cu-Pd) alloy nanocrystal catalyst that inhibits H2 and nitrite generation in electrolytes with different nitrate concentrations and varied pH. The interfacial sites of Cu-Pd alloys could enhance the adsorption energy and coverage of H* while increasing the reaction rate constant of NO_(2)*-to-NO*, which achieves a rapid conversion of NO_(2)* along with a decreased FE of NO_(2)-. Under ambient conditions, optimal FE(NH3) is close to 100% at a wide pH range, with the solar-to-chemical conversion efficiency approaching 4.29%. The combination of thermodynamics and kinetics investigations would offer new insights into the reduction mechanism of NO_(2)* for further development of nitrate reduction.

关键词： nitrate reduction ammonia synthesis Cu-Pd interfaces reaction kinetics break p H limitation

Numerical simulation of effects of cusp magnetic field on oxygen concentration of 300 mm CZ-Si

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Rare Metals 2012年第5期31卷 494-499页

作者： wang yongtao XU Wenting DAI Xiaolin XIAO Qinghua DENG Shujun YAN Zhirui ZHOU Qigang Semiconductor Materials Co. Ltd General Reseach Institute of Nonferrous Metals Beijing 100088 China General Research Institute for Non Ferrous Metals Beijing 100088 China

In magnetic Czochralski (MCZ) silicon growth, the distance and diameter of the electrified coils may affect the magnetic field intensity and melt flow. By changing the above parameters, the optimum geometric configuration of the coils was attempted. Through analyses of the oxygen concentration distribution of the crystal/melt interface, axial and radial velocity distribution of melt and the magnetic field intensity in the melt, it is found that smaller diameter of coils contributes to reducing the needed current intensity and production costs. For a given current intensity, there is a best distance of coils when the oxygen concentration at crystal/melt interface reaches the lowest. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012.

关键词： Computer simulation Magnetic fields Silicon

Dense Sphene-type Solid Electrolyte Through Rapid Sintering for Solid-state Lithium Metal Battery

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Chemical Research in Chinese Universities 2020年第3期36卷 439-446页

作者： wang yongtao GUO Xianwei LIN Zhivuan YANG Yubo WU Lingqiao LIU Huan YU Haijun College of Materials Science&Engineering Key Laboratory of Advanced Functional Materialshlinistty of EducationBeijing University of TechnologyBeijing 100124P.R.China

The sphene-type solid electrolyte with high ionic conductivity has been designed for solid-state lithium metal ***,the practical applications of solid electrolytes are still suffered by the low relative density and long sintering time of tens of hous with large energy ***,we introduced the spark plasma sintering technology for fabricating the sphene-type Li1.125Ta0.875Zr0.125SiO5 solid *** dense electrolyte pellet with high relative density of ca.97.4% and ionic conductivity of ca.1.44×10^-5S/cm at 30℃ can be obtained by spark plasma sintering process within the extremely short time of only *** the solid electrolyte provides stable electrochemical window of ca.6.0V(***^+/Li)and high electrochemical interface stability toward Li metal *** the enhanced interfacial contacts between electrodes and electrolyte pellet by the in-situ formed polymer electrolyte,the solid-state lithium metal battery with LiFePO4 cathode can deliver the initial discharge capacity of ca.154mA·h/g at 0.1C and the reversible capacity of ca.132mA·h/g after 70 cycles with high Coulombic efficienty of 99.5% at 55℃.Therefore,this study demonstrates a rapid and energy efficient sintering strategy for fabricating the solid electrolyte with dense structure and high ionic conductivity that can be practically applied in solid-state lithium metal batteries with high energy densities and safeties.

关键词： Solid-state lithium metal battery Sphene-type solid electrolyte Spark plasma sintering Dense structure Ionic conductivity

Automatic extraction of foreground objects from Mars images

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Geo-Spatial Information Science 2012年第1期15卷 17-25页

作者： wang Shuliang LIU Chang WU Shangru NIE Qianqian wang yongtao ZENG Shi ZHU Haifeng International School of Software Wuhan University129 Luoyu RoadWuhan 430079China Key Laboratory of Data Mining and Knowledge Engineering Inner Mongolia Autonomous RegionInner Mongolia UniversityHohhot 010021China Department of Geography East Michigan UniversityYpsilantiMI 48197USA

A novel method is proposed to automatically extract foreground objects from Martian surface *** characteristics of Mars images are distinct,*** illumination,low contrast between foreground and background,much noise in the background,and foreground objects with irregular *** the context of these characteristics,an image is divided into foreground objects and background *** filtering is first applied to rectify ***,wavelet transformation enhances contrast and denoises the ***,edge detection and active contour are combined to extract contours regardless of the shape of the *** results show that the method can extract foreground objects from Mars images automatically and accurately,and has many potential applications.

关键词： automatic object extraction Mars images homomorphic filtering wavelet transformation active contour edge detection

Interface science in polymer-based composite solid electrolytes in lithium metal batteries

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SusMat 2022年第3期2卷 264-292页

作者： Lingqiao Wu yongtao wang Xianwei Guo Peipei Ding Zhiyuan Lin Haijun Yu Faculty of Materials and Manufacturing Institute of Advanced Battery Materials and DevicesBeijing University of TechnologyBeijingChina Key Laboratory of Advanced Functional Materials Ministry of EducationBeijing University of TechnologyBeijingChina

Solid-state lithium metal batteries(SSLMBs)have attracted considerable attention as one of the most promising energy storage systems owing to their high safety and energy *** electrolytes,particularly polymer-based composite solid electrolytes(CSEs),are considered promising electrolyte candidates for ***,theirwide application is inhibited by various electrochemical issues,such as low ionic conductivity,the growth of lithium dendrites,and poor cycling stability,which are related to interface issues within *** this review,the parameters related to various interfaces in the CSE of SSLMBs,including the interfaces between the polymer matrix and inorganic fillers,between the CSEs and the cathode,and between the CSEs and the lithium metal anode,are *** issues and corresponding remediation strategies are ***,future perspectives based on interfacial engineering and the characterization of polymer/inorganic filler interactions are proposed for building high-performance CSEs for use in SSLMBs.

关键词： composite solid electrolyte interface electrolyte/electrode organic-inorganic composite solid electrolyte solid-state lithium metal battery