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Interstitial nitrogen-induced efficiency alcohol oxidation over heterogeneous N–CoMn_(2)O_(4) catalyst under visible-light

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Green Synthesis and Catalysis

Green Synthesis and Catalysis 2023年第4期4卷 293-299页

作者： hongwei li Yurong Zhang Jun Tang Guozheng Huang Ping Cui Qingping Ke College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China

Developing highly efficient and recyclable photocatalysts through harvesting solar light as energy is crucial to oxidation for industrial implementation,especially for simple transition metal oxidic catalysts without precious/heavy/rare metal dopants.Herein,we like to report the use of nitrogen-doped CoMn_(2)O_(4) oxide(N–CoMn_(2)O_(4))as a heterogeneous catalyst for efficient oxidation of various alcohols such as p/m/o-methyl-substituted aromatic alcohols,p-substituted aromatic alcohols including electron-donating and electron-withdrawing substituents,heterocycle-based alcohols and secondary aromatic alcohols to the corresponding aldehydes/ketones,under visible light(>420 nm)illumination and mild condition of oxygen as oxidant and room temperature.The relation of various Co-based oxides to their catalytic performance was studied.It is shown that the Co^(2+)species in N–CoMn_(2)O_(4),obviously increased by the doping of nitrogen,are acted as catalytic active species coupled with the synergistic effect between Co and Mn species for the enhanced visible-light selective oxidation of alcohols to aldehydes.A plausible catalytic mechanism is proposed basis of control experiments and published studies,which suggests that this oxidation process probably occurs on Co^(2+)þsites via an ionic reactive oxygen species pathway and ^(1)O2 and O2⋅^(-)species are the reactive oxygen species.This simple transition metal oxide-catalyzed aerobic oxidation provides a green alternative for the manufacture of aldehydes/ketones from alcohols.

关键词： Interstitial nitrogen Alcohol oxidation Room temperature CoMn_(2)O_(4) Visible-light

Ursolic acid inhibiting excessive reticulophagic flux contributes to alleviate ochratoxin A-induced endoplasmic reticulum stress- and mitochondrial-mediated apoptosis

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Food Science and Human Wellness 2024年

作者： Huiqiong Deng Wenying Chen lingyun Han Boyang Zhang Xun Luo Song Yao hongwei Wang Yao Zhou Shuangchao liu Xiao li Shen School of Public Health Zunyi Medical University Chongqing Fuling District Center for Disease Control and Prevention Key Laboratory of Maternal & Child Health and Exposure Science of Guizhou Higher Education Institutes Research and Development Department Allife Medicine Inc.

Foods and animal feeds frequently become contaminated with the nephrotoxic ochratoxin A (OTA). Our prior research has indicated that ursolic acid (UA)， which is widely present in fruits and medicinal plants， has the potential to alleviate nephrotoxicity triggered by OTA. Additionally， excessive induction of endoplasmic reticulum (ER)-phagy exacerbates OTA-induced apoptosis. Therefore， further investigation is essential to comprehend whether UA can mitigate OTA-induced apoptosis by influencing ER-phagy. This objective is accomplished through a series of experiments involving assessments of cell viability， apoptosis， fluorescence microscopy， and western blot analysis. The outcomes of these experiments reveal that pre-treatment with 4 μmol/L UA for 2 h can markedly reverse the elevated apoptotic rate， the co-localization of ER and lysosomes， and the protein expressions of GRP78， p-eIF2α， Chop， Bax， and Bak， as well as the reduced cell viability and the protein expressions of Lonp1， Trap1， p62， Tex264， FAM134B， Bcl-2， and Bcl-xl， all caused by exposure to 1 μmol/L OTA for 24 h in human proximal tubule epithelial-originated kidney-2 (HK-2) cells (P lified by UA pre-treatment (P < 0.05). In conclusion， OTA triggers a harmful feedback loop between ER stress (ERS) and excessive ER-phagy， thereby further promoting ERS- and mitochondrial-mediated apoptosis in vitro. However， this effect is significantly mitigated by UA through the inhibition of autophagosome-lysosome fusion， consequently blocking the excessive ER-phagic flux.

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Naive Bayes for value difference metric

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Frontiers of Computer Science 2014年第2期8卷 255-264页

作者： Chaoqun li liangxiao JIANG hongwei li Department of Mathematics China University of Geosciences Wuhan 430074 China Department of Computer Science China University of Geosciences Wuhan 430074 China

The value difference metric （VDM） is one of the best-known and widely used distance functions for nominal attributes. This work applies the instance weighting technique to improve VDM. An instance weighted value difference met- ric （IWVDM） is proposed here. Different from prior work, IWVDM uses naive Bayes （NB） to find weights for train- ing instances. Because early work has shown that there is a close relationship between VDM and NB, some work on NB can be applied to VDM. The weight of a training instance x, that belongs to the class c, is assigned according to the dif- ference between the estimated conditional probability P（c／x） by NB and the true conditional probability P（c／x）, and the weight is adjusted iteratively. Compared with previous work, IWVDM has the advantage of reducing the time complex- ity of the process of finding weights, and simultaneously im- proving the performance of VDM. Experimental results on 36 UCI datasets validate the effectiveness of IWVDM.

关键词： value difference metric instance weighting,naive Bayes distance-based learning algorithms

A Review on Ultrasonic-Assisted Forming:Mechanism,Model,and Process

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 147-170页

作者： Guangda Shao hongwei li Mei Zhan Shaanxi Key Laboratory of Precision Forming Technology and Equipment School of Materials Science and Engineering Northwestern Polytechnical University Xi’an China

Compared with conventional forming processes,ultrasonic-assisted forming technology with a high frequency and small amplitude can significantly improve the forming quality of materials.Owing to the advantages of reduced forming force,improved surface quality,avoidance of forming defects,and strengthened surface structure,ultrasonic-assisted forming technology has been applied to increasingly advanced forming processes,such as incremental forming,spinning,and micro-forming.However,in the ultrasonic-assisted forming process,there are multiple ultrasonic mechanisms,such as the volume effect and surface effect.The explanation of the effect of ultrasonic vibration(UV)on plastic deformation remains controversial,hindering the development of related technologies.Recently,many researchers have proposed many new theories and technologies for ultrasonic-assisted forming.To summarize these developments,systematic discussions on mechanisms,theoretical models,and forming performances are provided in this review.On this basis,the limitations of the current study are discussed.In addition,an outlook for ultrasonic-assisted forming is proposed:efficient and stable UV systems,difficulty forming components with complex geometry,explanation of the in-depth mechanism,a systematic theoretical prediction model,and multi-field-coupling energy-assisted forming are considered to be hot spots in future studies.The present review enhances existing knowledge of ultrasonic-assisted forming,and facilitates a fast reference for related researchers.

关键词： Ultrasonic vibration Forming Mechanism Model Processing performance

Dependence on forming parameters of an integral panel during the electromagnetic incremental forming process

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Chinese Journal of Aeronautics 2018年第7期31卷 1625-1634页

作者： Jinqiang TAN Mei ZHAN hongwei li State Key Laboratory of Solidification Process School of Materials Science & Engineering Northwestern Polytechnical University

Nowadays, more and more attentions are paid to electromagnetic incremental forming（EMIF）, especially for a part with a large-scale size, e.g., an integral panel with stiffened ribs. In this work, the bending of a panel into a double-curvature profile via EMIF is carried out experimentally and evaluated by comparing the formed profile with the desired profile. During the process,discharges at four positions along different discharge paths are designed. The effects of forming parameters on the die-fittingness of the workpiece are discussed, for which two evaluation indices are used to judge forming results. The results show that a discharge voltage in an incremental mode is helpful to improve the fittingness and avoid the collision rebound against the die at the same time.Discharging at the diagonal positions with the ‘‘X＂ discharge path exhibits the minimal shape deviation and the best forming uniformity. On the contrary, discharging at the parallel positions with the ‘‘Z＂ discharge path obtains the worst forming quality. Overlap of the coil at different positions should be given during EMIF; however, a lower overlap rate of the coil helps improve the forming quality. The results obtained in this work are useful for forming integral panels with stiffened ribs via the EMIF process.

关键词： Electromagnetic incrementalforming （EMIF） Forming uniformity Integral panel Parameters Shape deviation

Substructure Evolution of Ti-6Al-2Zr-1Mo-1V Alloy Isothermally Hot Compressed in α+β Two-Phase Region

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 533-544页

作者： Chuan WU He YANG hongwei li State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University

Substructure evolution significantly influences the flow behavior of titanium alloys in isothermal hot compression. This paper presents a physical experiment（isothermal hot compression and electron backscatter difraction, EBSD） and a cellular automaton（CA） method to investigate the substructure evolution of a near-α titanium alloy Ti-6Al-2Zr-1Mo-1V（TA15） isothermally compressed in the α ＋ β two-phase region. In the CA model, the subgrain growth, the transformation of low angle boundaries（LABs） to high angle boundaries（HABs） and the dislocation density evolution were considered. The dislocation density accumulating around the subgrain boundaries provided a driving force and made the transformation of the LABs to HABs. The CA model was employed to predict the substructure evolution, dislocation density evolution and flow stress. In addition, the efects of strain, strain rate and temperature on the relative frequency of the HABs were analyzed and discussed. To verify the CA model, the predicted results including the relative frequency of the HABs and the flow stress were compared with the experimental values.

关键词： Substructure evolution Cellular automaton modeling Dislocation density evolution EBSD technique

Genetic analysis of biomass and photosynthetic parameters in wheat grown in different light intensities

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Journal of Integrative Plant Biology 2014年第6期56卷 594-604页

作者： hongwei li Gui Wang Qi Zheng Bin li Ruilian Jing Zhensheng li State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Institute of Crop Sciences the Chinese Academy of Agricultural Sciences

Growth light intensities largely determine photo-synthesis, biomass, and grain yield of cereal crops. To explore the genetic basis of light responses of biomass and photosynthetic parameters in wheat （Triticum aestivum L.）, a quantitative trait locus （QTL） analysis was carried out in a doubled haploid （DH） population grown in low light （LL）, medium light （ML）, and high light （HL）, respectively. The results showed that the wheat seedlings grown in HL produced more biomass with lower total chlorophyll content （Chl）, carotenoid content, and maximum photochemical efficiency of photosystem II （Fv/Fm） while the wheat seed-lings grown in LL produced less biomass with higher Chl compared with those grown in ML. In total, 48 QTLs were identified to be associated with the investigated parameters in relation to growth light intensities. These QTLs were mapped to 15 chromosomes which individually explained 6.3%-36.0% of the phenotypic variance, of which chromo-somes 3A, 1D, and 6B were specifically involved in LL response, 5D and 7A specifically involved in ML response, and 4B specifically involved in HL response. Several light-responsive QTLs were co-located with QTLs for photosyn-thetic parameters, biomass, and grain weight under various conditions which may provide new hints to uncover the genetic control of photosynthesis, biomass, and grain weight.

关键词： Biomass carotenoids chlorophyll Fv/Fm quantitative trait locus Triticum aestivum L.

Characterization of glucose isomerase-producing bacteria and optimization of fermentation conditions for producing glucose isomerase using biomass

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Green Chemical Engineering 2023年第2期4卷 239-249页

作者： Aristide Laurel Mokale Kognou Chonlong Chio Janak Raj Khatiwada Sarita Shrestha Xuantong Chen hongwei li Yuen Zhu Zi-Hua Jiang Chunbao(Charles)Xu Wensheng Qin Department of Biology Lakehead UniversityThunder BayONP7B 5E1Canada Department of Chemical and Biochemical Engineering Western UniversityLondonONN6A 5B9Canada School of Environment and Resources Shanxi UniversityTaiyuan030006China Department of Chemistry Lakehead UniversityThunder BayONP7B 5E1Canada

Glucose isomerase(GI)is an enzyme with high potential applications.Characterization of GI producing bacteria with interesting properties from an industrial point of view is essential.Bacillus sp.,Paenarthrobacter sp.,Chryseobacterium sp.,Hymenobacter sp.,Mycobacterium sp.,and Stenotrophomonas sp.were isolated from soil samples.Optimization of enzyme production yield was investigated in various fermentation conditions using response surface methodology.All isolates exhibited maximum GI activity at 40℃,pH 6–8 after 4 days of incubation.A mixture of peptone/yeast extract or tryptone/peptone enhanced higher enzyme production.The same trend was observed in fermentation medium containing 1%xylose or 2%–2.5%wheat straw.This study advanced the knowledge of these bacterial isolates in promoting wheat straw as feedstock for the bio-based industry.

关键词： Cellulolytic bacteria Glucose/xylose isomerase 16S rRNA Biomass conversion

新兴的多元铋系光催化剂:结构分类、制备、改性及应用

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Chinese Journal of Catalysis 2024年第2期57卷 18-50页

作者：李敏于世新黄洪伟北京林业大学环境科学与工程学院水体污染源控制技术北京市重点实验室污染水体源控制与生态修复技术北京市高等学校工程研究中心北京100083 北京林业大学林木资源高效生产全国重点实验室林木生物质化学北京市重点实验室北京100083 中国地质大学(北京)材料科学与工程学院地质碳储与资源低碳利用教育部工程研究中心非金属矿物与固废资源材料化利用北京市重点实验室矿物岩石材料开发应用国家专业实验室北京100083

光催化技术能够利用太阳能实现污染物降解和能源物质合成,被认为是解决环境污染和能源短缺两大难题的极具潜力的方法之一.探索新型光催化剂是推进光催化技术发展的重要途径.铋系光催化剂因具有独特的晶体结构、良好的杂化电子能带结构... 详细信息

光催化技术能够利用太阳能实现污染物降解和能源物质合成,被认为是解决环境污染和能源短缺两大难题的极具潜力的方法之一.探索新型光催化剂是推进光催化技术发展的重要途径.铋系光催化剂因具有独特的晶体结构、良好的杂化电子能带结构和多元的化学组成而表现出较好的光催化性能.多种传统铋系光催化剂已被广泛的制备和研究,它们具有不同的光吸收能力以及氧化还原能力,已经在污染物降解、水分解产氧等应用中取得成效.近年来越来越多的新型多元铋系光催化剂被开发,为不同的光催化反应提供了更多催化剂选择.因此有必要对近几年开发的新型铋系光催化材料进行总结,并为铋系光催化材料研究和发展提供一定的参考.本文综述了近十年共60余种新兴多元铋系光催化剂的研究进展,从多个角度进行系统的梳理和总结.首先,对60余种新型铋系光催化材料进行了汇总,并根据晶体结构构型进行了分类,包括Sillén,Sillén-related,Aurivillius,Sillén-Aurivillius以及其他结构类型共5大类,每种材料都具有从原子尺度到宏观尺度的独特结构,因此本文进一步对新型铋系材料的结构性规律进行了总结,主要分为层状铋系化合物和非层状铋系化合物.在此基础上,概括了材料的合成方法,目前多元铋系光催化材料的合成方法主要为水热溶解热法和高温固相法,分别讨论了不同合成方法对不同结构类型材料制备的优势,尤其在获得高性能的光催化剂方面,材料合成方法起到决定性作用.此外,归纳了针对提高新兴多元铋系光催化剂性能的修饰策略.材料改性修饰是目前铋系材料研究的热点,适当的合成方法结合相应的改性修饰可以获得更理想的光催化材料,阐述了形貌调控、特定晶面暴露、异质结构建、极性电场构建等方法对新型铋系材料性能促进的机理,并对各种策略存在的优缺点进行了总结.同时概述了新型多元铋系材料在不同光催化应用领域的进展,包括液体和气体污染物的降解、水裂解生成氢气和氧气、二氧化碳还原、固氮、硫化氢裂解生成氢气、有机合成等,为拓展不同多元铋系光催化剂的应用领域提供参考.最后,本文对新型多元铋系材料目前仍存在的关键问题以及未来的研究趋势进行了展望,希望能为铋系材料的进一步研发提供一定的启发.

关键词：铋系材料光催化晶体结构层状结构光催化应用