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Vertical distribution and temporal evolution of formaldehyde and glyoxal derived from MAX-DOAS observations:The indicative role of VOC sources

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Journal of Environmental Sciences 2022年第12期34卷 92-104页

作者： Qianqian Hong Cheng Liu Qihou Hu Yanli Zhang Chengzhi Xing Jinping Ou Wei Tan Haoran Liu Xiaoqing Huang Zhenfeng Wu School of Environment and Civil Engineering Jiangnan UniversityWuxi 214122China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Environmental Optics&Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China Guangdong Key Laboratory of Environmental Protection and Resources Utilization State Key Laboratory of Organic GeochemistryGuangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 510632China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Formaldehyde(HCHO)and glyoxal(CHOCHO)are important oxidization intermediates of most volatile organic compounds(VOCs),but their vertical evolution in urban areas is not well understood.Vertical profiles of HCHO,CHOCHO,and nitrogen dioxide(NO_(2))were retrieved from ground-based Multi-Axis Differential Optical Absorption Spectroscopy(MAXDOAS)observations in Hefei,China.HCHO and CHOCHO vertical profiles prefer to occur at higher altitudes compared to NO_(2),which might be caused by the photochemistry-oxidation of longer-lived VOCs at higher altitudes.Monthly means of HCHO concentrations were higher in summer,while enhanced amounts of NO_(2)were mainly observed in winter.CHOCHO exhibited a hump-like seasonal variation,with higher monthly-averaged values not only occurred in warm months(July-August)but also in cold months(November-December).Peak values mainly occurred during noon for HCHO but emerged in the morning for CHOCHO and NO_(2),suggesting that HCHO is stronger link to photochemistry than CHOCHO.We further use the glyoxal to formaldehyde ratio(GFR)to investigate the VOC sources at different altitudes.The lowest GFR value is almost found in the altitude from 0.2 to 0.4 km,and then rises rapidly as the altitude increases.The GFR results indicate that the largest contributor of the precursor VOC is biogenic VOCs at lower altitudes,while at higher altitudes is anthropogenic VOCs.Our findings provide a lot more insight into VOC sources at vertical direction,but more verification is recommended to be done in the future.

关键词： Formaldehyde glyoxal MAX-DOAS Vertical distribution VOC

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Crosslinking Mechanism of Soy Protein-based Adhesives based on glyoxal and a Compound of Protein Model

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 942-950页

作者：曹龙 LIANG Jiankun ZHANG Qiaoyan XI Xuedong 吴志刚雷洪 Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China College of Civil Engineering Kaili UniversityQiandongnanKaili556011China Zhazuo State-owned Forest Farm Guiyang550299China College of Forestry Guizhou UniversityGuiyang550025China School of Chemistry Materials Engineering Zhejiang A&F UniversityHangzhou311300China

The crosslinking mechanism of glyoxal and asparagine was analyzed,and the relationship between the mechanism and practical performances of soy protein-based adhesives was also discussed.It is shown that when pH=1 and 3,glyoxal reacted with asparagine in the form of major cyclic ether compounds.When pH=5,glyoxal reacted with asparagine in two structural forms of sodium glycollate and cyclic ether compounds.However,amidogens of asparagine were easy to develop protonation under acid conditions.Supplemented by the instability of cyclic ether compounds,the reaction activity and reaction degree between glyoxal and asparagine were relatively small.Under alkaline conditions,glyoxal mainly reacted with asparagine in the form of sodium glycollate.With the increase of pH,the polycondensation was more sufficient and the produced polycondensation products were more stable.The reaction mechanism between glyoxal and asparagine had strong correspondence to the practical performances of the adhesives.glyoxal solution could develop crosslinking reactions with soy protein under both acid and alkaline conditions.Bonding strength and water resistance of the prepared soy protein-based adhesives were increased significantly.When pH>7,glyoxal had relatively high reaction activity and reaction intensity with soy protein,and the prepared adhesives had high crosslinking density and cohesion strength,showing relatively high bonding strength,water resistance and thermal stability.

关键词： soy protein wood adhesives glyoxal model compounds crosslinking

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glyoxal induced advanced glycation end products formation in chicken meat emulsion instead of oxidation

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Food Science and Human Wellness 2022年第4期11卷 828-836页

作者： Rui Fang Zongshuai Zhu Anthony Pius Bassey Iftikhar Ali Khan Ming Huang College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China Center Testing International Pinbiao(Jiangsu) Certifi cation Technology Co.Ltd.Nanjing 210046China Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced StudyShenzhen UniversityShenzhen 518060China Nanjing Huangjiaoshou Food Science and Technology Co.Ltd. Jiangsu Research Center for Livestock and Poultry Products Processing Engineering TechnologyNanjing 211200China

Advanced glycation end products(AGE) are potential harmful substances formed in the advanced Maillard reaction and increasingly investigated in muscle foods. However, the contribution of oxidation to the AGE formation is controversial. Moreover, reports on glyoxal(GO) induced AGE formation in chicken meat emulsion(CME) are limited. Thus, the effects of GO on emulsifying properties, rheological behavior and AGE formation in CME were investigated. Our findings exhibited that levels of Nε-carboxymethyllysine(CML) and Nε-carboxyethyllysine(CEL) were associated with lipid oxidation but not significantly(P > 0.05). Levels of AGE peaked when GO concentration ranged from 5 mmol/L(CML) to 10 mmol/L(CEL). The droplets’ aggregation associated with the disulfide bond when the concentration of GO was at 0.5–30 mmol/L while non-disulfide bond association occurred at 30–50 mmol/L GO concentration. In conclusion, compared to the effect of oxidation, GO exhibited the main role in the AGE formation of CME. This study will provide theoretical significance for further understanding and controlling the formation of AGE in CME.

关键词： glyoxal Emulsion Oxidation Advanced glycation end products Chicken meat

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Investigating the impact of glyoxal retrieval from MAX-DOAS observations during haze and non-haze conditions in Beijing

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Journal of Environmental Sciences 2019年第6期31卷 296-305页

作者： Zeeshan Javed Cheng Liu Muhammad Fahim Khokhar Chengzhi Xing Wei Tan Muhammad Ahmed Subhani Abdul Rehman Aimon Tanvir School of Earth and Space Sciences University of Science and Technology of China Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Key Lab of Environmental Optics & Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Anhui Province Key Laboratory of Polar Environment and Global Change USTC Institute of Environmental Sciences and Engineering National University of Sciences and Technology

This study presents the Multi Axis Differential Optical Absorption Spectroscopy(MAXDOAS) measurements for glyoxal(CHOCHO) in Beijing, China(39.95°N, 116.32°E). CHOCHO is the smallest compound of di-carbonyl group. As a primary sink of CHOCHO, its photolysis with NOx(oxides of nitrogen) results in the production of tropospheric ozone. Therefore,the focus of CHOCHO DOAS measurements is increasing in trend. We did the measurements from 09 May 2017 to 09 September 2017. The study was conducted to compare different retrieval settings in order to reveal best DOAS fit settings for CHOCHO;furthermore, effect of haze and non-haze days on CHOCHO concentration was examined.The root mean square of residual and Differential Slant Column density(dSCD) error was reduced when measurements were done with lower wavelength limit around 432–438 nm and upper intervals around 455–460 nm. Thus, lower wavelength intervals around432–438 nm and upper intervals around 457–460 nm were best for the retrieval of dSCDs for CHOCHO. Meteorological conditions like haze or non-haze days did not have significant effect on DOAS fit parameters. The CHOCHO vertical column densities range from 1.33 E +14 to 9.77 E + 14 molecules/cm2 during the study period with average of 6.16 E +14 molecules/cm2. The results indicated that during haze days CHOCHO concentration was higher because of lower rate of photolysis and atmospheric oxidation potential. Our results did not show any significant weekend effect on CHOCHO atmospheric concentration.

关键词： glyoxal DOAS Retrieval settings Photolysis Haze days

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Investigating missing sources of glyoxal over China using a regional air quality model (RAMS-CMAQ)

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Journal of Environmental Sciences 2018年第9期30卷 108-118页

作者： Jialin Li Meigen Zhang Guiqian Tang Fangkun Wu Leonardo M.A. Alvarado Mihalis Vrekoussis Andreas Richter John P. Burrows State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPQ) Institute of Atmospheric Physics (IAP)Chinese Academy of Sciences (CAS) Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Institute of Environmental Physics and Remote Sensing IUP University of Bremen D-28203 Bremen Germany Center of Marine Environmental Sciences MARUM University of Bremen D-28203 Bremen Germany Energy Environment and Water Research Center the Cyprus Institute CY2121 Nicosia Cyprus

Currently, modeling studies tend to significantly underestimate observed space-based glyoxal （CHOCHO） vertical column densities （VCDs）, implying the existence of missing sources of giyoxal. Several recent studies suggest that the emissions of aromatic compounds and molar yields of glyoxal in the chemical mechanisms may both be underestimated, which can affect the simulated glyoxal concentrations. In this study, the influences of these two factors on glyoxal amounts over China were investigated using the RAMS-CMAQ modeling system for January and July 2014. Four sensitivity simulations were performed, and the results were compared to satellite observations. These results demonstrated significant impacts on glyoxal concentrations from these two factors. In case 1, where the emissions of aromatic compounds were increased three-fold, improvements to glyoxal VCDs were seen in high anthropogenic emissions regions. In case 2, where molar yields of glyoxal from isoprene were increased five-fold, the resulted concentrations in July were B-B-fold higher, achieving closer agreement between the modeled and measured glyoxal VCDs. The combined changes from both cases 1 and 2 were applied in case B, and the model succeeded in further reducing the underestimations of glyoxal VCDs. However, the results over most of the regions with pronounced anthropogenic emissions were still underestimated. So the molar yields of giyoxal from anthropogenic precursors were considered in case 4. With these additional mole yield changes （a two-fold increase）, the improved concentrations agreed better with the measurements in regions of the lower reaches of the Yangtze River and Yellow River in January but not in July.

关键词： glyoxal Volatile organic compounds Molar yields RAMS-CMAQ China

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Formaldehyde Free Renewable Thermosetting Foam Based on Biomass Tannin with a Lignin Additive

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Journal of Renewable Materials 2022年第11期10卷 3009-3024页

作者： Bowen Liu Yunxia Zhou Hisham Essawy Shang Feng Xuehui Li Jingjing Liao Xiaojian Zhou Jun Zhang Sida Xie Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China Department of Polymers and Pigments National Research CentreCairo12622Egypt Key Laboratory for Forest Resources Conservation and Utilisation in the Southwest Mountains of China(Southwest Forestry University) Ministry of EducationKunming650224China

This study presents easily prepared free formaldehyde bio-based foam based on a prepared thermosetting resin comprising tannin–lignin–furfuryl alcohol-glyoxal(TLFG)via mechanical stirring in presence of ether as a foaming agent.The foam was developed through a co-polycondensation reaction of glyoxal and furfuryl alcohol with condensed tannin and lignin,which is a forest-derived product.Investigation using scanning electron microscopy(SEM)showed more closed-cell structure without cracks and collapse in the TLFG foam,with a higher apparent density with respect to tannin–furanic–formaldehyde(TFF)foam.Differential scanning calorimetry(DSC),dynamic thermomechanical analysis(DTMA),and thermogravimetric analysis(TGA)investigations revealed that the curing process of TLFG foam proceeds easily even at a lower temperature.Additionally,it acquired higher heat resistance than TFF foam.Moreover,TLFG has a more robust chemical network structure,which contributes efficiently to the mechanical strength and a lower pulverization degree compared with TFF-derived foam.Fourier transform infrared spectrometry(FTIR)and electrospray ionization mass spectrometry(ESI-MS)proved that the cross-inking reactions between tannin,lignin,furfuryl alcohol,and glyoxal have been proceeded efficiently.

关键词： Foam materials heat resistance tannin lignin glyoxal compressive strength

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HPLC determination of glyoxal in aldehyde solution with 3-methyl-2-benzothiazolinone hydrazone

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 117-121页

作者： Yamei ZHU Xiaoli YAO Shaohui CHEN Qun CUI Haiyan WANG College of Chemistry and Chemical Engineering Nanjing University of TechnologyNanjing 210009China Yangzi Institute Sinopec Yangzi Petrochemical Company Ltd.Nanjing 210048China

Based on the absorption property of a diazine that can be formed by reaction of glyoxal and 3-methyl-2-benzothiazolinone hydrazone(MBTH)in the Ultravioletvisible(UV-vis)spectral region,a HPLC method was developed for the determination of glyoxal in acetaldehyde solution.glyoxal was derivatised from MBTH and the derivatives(diazine)were analyzed by HPLC for identification and quantification.The determination was performed on a ZORBAX Eclipse XDB-C18 column(4.6250 mm,5 mm)at 35℃ with an injection volume of 10 mL,using a mixture of acetonitrile-water solvent(99∶5,v∶v)as a mobile phase with a flow rate of 0.8 mL·min^(–1).The proper derivative reaction conditions were the temperature of 70℃,MBTH to carbonyl molar ratio of 12,and reaction time of 110 min.The glyoxal diazine was a yellow dye with a maximum molar absorptivity at 401 nm and its retention time was 5.2 min under optimal HPLC conditions.The standard curve for glyoxal had a strong linear relationship with a regression coefficient(R2=0.999)in the range of 0.002–0.020 g·L^(–1).The analysis of glyoxal in an oxidising solution gave accurate results with a relative standard deviation(RSD)value of 0.55%.The average relative recovery was 102%.This efficient HPLC technique is also proposed for detecting other dicarbonyl compounds besides glyoxal.

关键词： HPLC glyoxal 3-methyl-2-benzothiazolinone hydrazone diazine dicarbonyl compounds

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Study on the Soy Protein-Based Adhesive Cross-Linked by glyoxal

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Journal of Renewable Materials 2021年第2期9卷 205-218页

作者： Zhigang Wu Jiankun Liang Hong Lei Bengang Zhang Xuedong Xi Lifen Li Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China College of Forestry Guizhou UniversityGuiyang550025China Kaili University Qiandongnan556011China

Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in water in different forms at different pH levels.Under alkaline conditions,glyoxal transformed to glycolate through the intramolecular disproportionation reaction.Under acidic conditions,although some of glyoxal transformed to glycolate as what happened under alkaline conditions,most of glyoxal molecules existed in the form of fiveor six-membered cyclic ether structure.No ethylene tetraol or free aldehyde group was actually detected under these conditions.Although glyoxal reacted with soy protein under both acidic and alkaline conditions,alkaline conditions were more favorable for the improvement of mechanical performance and water resistance of soybased adhesives than acid conditions.

关键词： glyoxal soy protein-based adhesive cross-link

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Oxidation of glyoxal to glyoxylic acid by oxygen over V_2O_5/C catalyst

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Chinese Chemical Letters 2008年第2期19卷 245-248页

作者： Yu Lan Niu Zheng Xu Min Li Rui Feng Li Key Laboratory of Coal Science and Technology MOE Institute of Special Chemicals Taiyuan University of TechnologyTaiyuan 030024 PR China Department of Chemical Engineering Taiyuan Institute of Technology Taiyuan 030008 PR China

A novel vanadium oxide catalyst supported on active carbon was prepared by an incipient wetness impregnation method, and the precursor was obtained from oxalic acid aqueous solutions of NH4VO3. The catalyst was applied liquid phase oxidation of glyoxal to glyoxylic acid. It was found that V2O5/C catalyst exhibited obvious activity for glyoxal oxidation. Glyoxylic acid could be obtained without pH regulation during the reaction. By using this catalyst, the conversion of glyoxal and the yield of glyoxalic acid were 29.2% and 13.6%, respectively at 313 K and oxygen flow 0.1 L/rain after reaction for 10 h.

关键词： glyoxal Glyoxylic acid Vanadium catalyst Oxidation

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V_2O_5/C catalyst for liquid phase oxidation of glyoxal to glyoxylic acid

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Science China Chemistry 2009年第7期52卷 1057-1062页

作者： NIU YuLan1,2 & LI RuiFeng1 1 Key Laboratory of Coal Science and Technology, Ministry of Education, Institute of Special Chemicals, Taiyuan University of Technology, Taiyuan 030024, China 2 Department of Chemical Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China Key Laboratory of Coal Science and Technology Ministry of Education Institute of Special Chemicals Taiyuan University of Technology Taiyuan China Department of Chemical Engineering Taiyuan Institute of Technology Taiyuan China

A study of the catalytic activity of V2O5/C catalyst for the oxygen oxidation of glyoxal has been made, showing that glyoxylic acid can be formed without control of pH value and there is little oxalic acid from the excessive oxidation of glyoxylic acid. The studies of XRD and TEM have shown that V2O5 diffraction peaks gradually strengthen with the increase of the content of V2O5. With the content of 3% V2O5 and the calcination temperature of 573 K, V2O5/C catalyst displayed the best activity and selectivity. The conversion of glyoxal and the selectivity of glyoxylic acid reached 18.76% and 77.70% after 5 h, respectively. Moreover, V2O5/C catalyst showed small deactivation after recycling three times, which indicates that V2O5/C has a higher stability than noble metal catalysts in the reaction medium.

关键词： glyoxal glyoxylic acid V2O5/C catalyst

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