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Effects of oxidizing environment on digestate humification and identification of substances governing the dissolved organic matter (DOM) transformation process

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1520-0

摘要：

• Liquid digestate humification was investigated under different oxidizing environment.

关键词： Liquid digestate     MnO2     Oxygen     DOM transformation     Humic-like acids    

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Variation in humic and fulvic acids during thermal sludge treatment assessed by size fractionation, elementary

Yuning YANG,Huan LI,Jinyi LI

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 854-862 doi: 10.1007/s11783-014-0755-9

摘要： Thermal pretreatment can be applied to sludge anaerobic digestion or dewatering. To analyze the variation in humic substances during thermal sludge treatment, sludge humic and fulvic acids were extracted before and after 30-min thermal treatment at 180°C, and then their contents, molecular weight distributions, elementary compositions, and spectral characteristics were compared. The results showed that the total contents of humic and fulvic acids in the sludge almost remained constant during thermal treatment, but 35% of humic and fulvic acids were dissolved from the sludge solids. Moreover, both humic and fulvic acids were partly decomposed and 32% of humic acids were converted to fulvic acids. The median value of the molecular weights of humic acids decreased from 81 to 41 kDa and that of fulvic acids decreased from 15 to 2 kDa. Besides the reduction in molecular size, the chemical structures of humic and fulvic acids also exhibited a slight change, i.e. some oxygen functional groups disappeared and aromatic structures increased after thermal sludge treatment.

关键词： sludge     thermal treatment     humic acids     fulvic acids    

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Effects of water quality on the coagulation performances of humic acids irradiated with UV light

Wendong WANG,Qinghai FAN,Zixia QIAO,Qin YANG,Yabo WANG,Xiaochang WANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 147-154 doi: 10.1007/s11783-014-0749-7

摘要： The presence of humic acid in drinking water treatment has received significant attention in recent years because of its adverse effects on the removal of many pollutants in coagulation. In this paper, the effects of water quality including pH, turbidity, alkalinity, and hardness on the removal of humic acid were investigated in a UV light hybridized coagulation process. Our results suggested that UV light radiation could effectively improve the removal rate of humic acid in coagulation under both neutral and basic conditions, and the variations of the selected water quality parameters had little adverse effect on the function of UV light. After UV light radiation, the removal rate of the nitro-humic acid (NHA) increased from 20% to 60% in coagulation, and increased further to 75% and 85% for the raw waters with 10.0 NTU kaolin and 100 mg·L hardness, respectively. In addition to NHA, the removal rates of the humic acid extracted from peat coal (PHA) and the humic acid provided by Japan metals and chemicals company (JHA) in coagulation were also improved, both in the range of 80%–90% after undergoing UV light radiation. By changing the radiation location from prior to coagulation to the flocculation process, similar experimental results were obtained. The formation of positive charged sites after UV light radiation was considered to be the primary factor that led to an enhanced removal of the humic acid in coagulation.

关键词： coagulation     drinking water     humic acid     UV light radiation     water quality    

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Effect of metal ion-doping on characteristics and photocatalytic activity of TiO

Rongfang YUAN,Beihai ZHOU,Duo HUA,Chunhong SHI

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 850-860 doi: 10.1007/s11783-014-0737-y

摘要： The effect of ion-doping on TiO nanotubes were investigated to obtain the optimal TiO nanotubes for the effective decomposition of humic acids (HA) through O /UV/ion-doped TiO process. The experimental results show that changing the calcination temperature, which changed the weight fractions of the anatase phase, the average crystallite sizes, the Brunauer-Emmett-Teller surface area, and the energy band gap of the catalyst, affected the photocatalytic activity of the catalyst. The ionic radius, valence state, and configuration of the dopant also affected the photocatalytic activity. The photocatalytic activities of the catalysts on HA removal increased when Ag , Al , Cu , Fe , V , and Zn were doped into the TiO nanotubes, whereas such activities decreased as a result of Mn - and Ni -doping. In the presence of 1.0 at.% Fe -doped TiO nanotubes calcined at 550°C, the removal efficiency of HA was 80% with a pseudo-first-order rate constant of 0.158 min . Fe in TiO could increase the generation of ·OH, which could remove HA. However, Fe in water cannot function as a shallow trapping site for electrons or holes.

关键词： TiO2 nanotubes     ion-doping     humic acids     pseudo-first-order     mechanism    

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Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

《医学前沿（英文）》 2018年 第12卷 第6期   页码 608-623 doi: 10.1007/s11684-018-0644-x

摘要： Diabetes is a widespread, rapidly increasing metabolic disease that is driven by hyperglycemia. Early glycemic control is of primary importance to avoid vascular complications including development of retinal disorders leading to blindness, end-stage renal disease, and accelerated atherosclerosis with a higher risk of myocardial infarction, stroke and limb amputations. Even after hyperglycemia has been brought under control, “metabolic memory,” a cluster of irreversible metabolic changes that allow diabetes to progress, may persist depending on the duration of hyperglycemia. Manipulation of bile acid (BA) receptors and the BA pool have been shown to be useful in establishing glycemic control in diabetes due to their ability to regulate energy metabolism by binding and activating nuclear transcription factors such as farnesoid X receptor (FXR) in liver and intestine as well as the G-protein coupled receptor, TGR5, in enteroendocrine cells and pancreatic -cells. The downstream targets of BA activated FXR, FGF15/21, are also important for glucose/insulin homeostasis. In this review we will discuss the effect of BAs on glucose and lipid metabolism and explore recent research on establishing glycemic control in diabetes through the manipulation of BAs and their receptors in the liver, intestine and pancreas, alteration of the enterohepatic circulation, bariatric surgery and alignment of circadian rhythms.

关键词： bile acids     metabolic memory     diabetes     circadian rhythm     bariatric surgery    

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Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate

《环境科学与工程前沿（英文）》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1719-8

摘要： Converting biomass materials to humic acid is a sustainable method for humic acid production and achieve biomass valorization. A two-step hydrothermal treatment method was adopted in this study to produce humic acid from corn stalks. In the first step of the process, hydrochar was prepared at different hydrothermal temperatures and pH values. Their chemical properties were then analyzed, and the hydrochar-derived humic acids were produced under alkaline hydrothermal conditions (denoted as HHAalk). The hydrochar, prepared under high temperature (200 °C) and strong acidic (pH 0) conditions, achieved high HHAalk yields (i.e., 67.9 wt% and 68.8 wt% calculated based on weight of hydrochar). The sources of HHAalk formation were as follows: 1) production in the hydrochar preparation stage, and 2) increment under the alkaline hydrothermal treatment of hydrochar. The degree of hydrochar unsaturation was suggested as an indicator for evaluating the hydrochar humification potential under alkaline hydrothermal conditions. This study provides an important reference for the preparation of suitable hydrochar with high hydrothermal humification potential.

关键词： Biowaste     Hydrochar     Humic acid     Hydrothermal parameter     Unsaturation    

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Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 817-829 doi: 10.1007/s11705-022-2254-z

摘要： Amino acids are important nitrogen-containing chemicals that have a variety of applications. Currently, fermentation is the widely employed method to produce amino acids; however, the products are mostly limited to natural amino acids in the L-configuration. Catalytic synthesis is an alternative approach for the synthesis of amino acids with different types and configurations, where the use of renewable biomass-based feedstocks is highly attractive. To date, several lignocellulose and triacylglycerol-derived intermediates, typically α-keto acids and α-hydroxyl acids, have been transformed into amino acids via the amination reaction in the presence of additional nitrogen sources (i.e., NH3·H2O). Making full use of inherent nitrogen in biomass (i.e., chitin and protein) to produce amino acids avoids the use of extra nitrogen sources and meets the requirements of green chemistry, which is attracting increasing attention. In this review, we summarize different chemical-catalytic systems for the transformation of biomass to amino acids. An outlook on the challenges and opportunities for more effective production of amino acids from biomass by catalytic methods is provided.

关键词： biomass     amino acids     chitin     nitrogen-containing compounds     lignocellulose    

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Electrochemical oxidation of humic acid at the antimony- and nickel-doped tin oxide electrode

TANG Chengli,YAN Wei,ZHENG Chunli

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 337-344 doi: 10.1007/s11783-013-0545-9

摘要： This work investigated the degradation of humic acid (HA) in aqueous solution by electrochemical oxidation with Antimony- and Nickel-doped Tin oxide electrode (Ni-Sb-SnO /Ti electrode) as the anode. Initial concentrations of HA ranged from 3 to 9 mg·L . Under such a concentration scope, the degradation of HA was a mass transfer controlled process. Degradation rate increased with the increase of HA initial concentration. Test on the effect of tert-butanol revealed that ·OH played an important role in the oxidation of HA. The absence of cation Ca was beneficial to HA degradation, which suggested that both indirect and direct electrolyze happened during the whole electrochemical oxidation process. Alkaly (pH= 12) and neutral (pH= 7) conditions were benefical to HA degradation.

关键词： electrochemical oxidation     humic acid (HA)     natural water     Ni-Sb-SnO2/Ti electrode    

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Effects of humic acid on residual Al control in drinking water treatment plants with orthophosphate addition

Wendong WANG, Hua LI, Zhenzhen DING, Xiaochang WANG, Rui LIU

《环境科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 470-476 doi: 10.1007/s11783-012-0422-y

摘要： This study aimed to investigate the effects of humic acid (HA) on residual Al control in drinking water facilities that used orthophosphate addition. The results showed that adding orthophosphate was an effective method for residual Al control for the raw water without HA. When orthophosphate was added at 1.0 min before the addition of poly aluminum chloride (PACl), the concentrations of soluble aluminum (Sol-Al) and total aluminum (Tot-Al) residue were 0.08 and 0.086 mg·L , respectively; both were reduced by 46% compared with the control experiment. The presence of HA would notably increase the residual Al concentration. For the raw water with 5 mg·L of HA, the concentrations of Sol-Al and Tot-Al increased from 0.136 and 0.174 mg·L to 0.172 and 0.272 mg·L , respectively. For water with a HA concentration above 5 mg·L , orthophosphate was ineffective in the control of residual Al, though there were still parts of orthophosphate were removed in coagulation. The amounts of Al removal were positively correlated with the solids freshly formed in coagulation. Similar to the raw water without HA, the best Al control was obtained with orthophosphate salt added at 1.0 min before PACl. HA concentrations in the raw water, solution pH, and the orthophosphate dosage suitable for residual Al control by orthophosphate precipitation were also investigated.

关键词： coagulation     drinking water     humic acid     orthophosphate     residual Al    

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Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

《环境科学与工程前沿（英文）》 2021年 第15卷 第1期 doi: 10.1007/s11783-020-1297-y

摘要： Abstract • Humification evolution was identified with non-destructive characterization method. • Humification process from precursors to fulvic and humic acid was confirmed. • MnO2 alone had limited oxidation ability to form HA. • MnO2 played a key role as a catalyst to transform FA to HA in the presence of O2. • MnO2 could affect the structure of the humification products. Abiotic humification is important in the formation and evolution of organic matter in soil and compost maturing processes. However, the roles of metal oxides in abiotic humification reactions under micro-aerobic remain ambiguous. The aim of this study was to use non-destructive measurement methods to investigate the role of MnO2 in the evolution of humic substances (HSs) during oxidative polymerization of polyphenol-amino acid. Our results suggested a synergistic effect between MnO2 and O2 in promoting the polymerization reaction and identified that MnO2 alone had a limited ability in accelerating the transformation of fulvic acid (FA) to humic acid (HA), whereas O2 was the key factor in the process. Two-dimensional correlation spectroscopy (2D-COS) showed that the evolution in the UV-vis spectra followed the order of 475–525 nm>300–400 nm>240–280 nm in the humification process, indicating the formation of simple organic matter followed by FA and then HA. 13C nuclear magnetic resonance (13C NMR) analysis revealed that the products under both air and N2 conditions in the presence of MnO2 had greater amounts of aromatic-C than in the absence of MnO2, demonstrating that MnO2 affected the structure of the humification products. The results of this study provided new insights into the theory of abiotic humification.

关键词： Two-dimensional correlation spectroscopy (2D-COS)     Humic substances (HSs)     Humification     Manganese dioxide     Polyphenol    

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Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

《环境科学与工程前沿（英文）》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1458-7

摘要：

•Tryptophan protein, and aromatic protein I/II were the key identified proteins.

关键词： Sludge pretreatments     Dissolved organic nitrogen     Proteins     Amino acids     Structural equation model     Metagenomic sequencing analysis.    

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Characterization of soil low-molecular-weight organic acids in the Karst rocky desertification region

Xiaoliang LI, Xiaomin CHEN, Xia LIU, Lianchuan ZHOU, Xinqiang YANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 195-203 doi: 10.1007/s11783-012-0391-1

摘要： Soil low-molecular-weight (LMW) organic acids play important roles in the soil-forming process and the cycling of nutrients in Karst regions. In this study, we quantified the contents of LMW organic acids (including lactate, acetate, formate, malate, and oxalate) in soil solution over the Karst region of Guizhou Province, China using ion chromatography. The concentration of total LMW organic acids in topsoil solution ranged from 0.358 to 1.823 μmol·g , with an average of 0.912 μmol·g . The mean concentrations of lactate, acetate, formate, malate, and oxalate were 0.212±0.089, 0.302±0.228, 0.301±0.214, 0.014±0.018 and 0.086±0.118 μmol·g , respectively. There were also significant difference in the contents of these acids among four phases of rocky desertification, and their concentrations decreased with the aggravation of rocky desertification. The concentrations of the LMW organic acids were significantly positive correlated each other. Significant positive correlations were also observed among individual LMW organic acids in soil solution, and between them and soil available P, available K, exchangeable Ca, respectively. Furthermore, the concentrations of LMW organic acids were significantly positively correlated with inorganic anions (chlorides, nitrates, and sulfates) in Karst topsoil solution. Therefore, the concentrations of soil LMW organic acids might be one of driving force in the Karst rock desertification process in Guizhou Province.

关键词： Karst rocky desertification     low-molecular-weight (LMW) organic acids     distribution characteristics     soil    

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Abiotic association of phthalic acid esters with humic acid of a sludge landfill

Xiaoli CHAI, Yongxia HAO, Xin ZHAO, Guixiang LIU, Ying ZHU, Rong JI, Jun WU, Huanhuan TONG, Youcai ZHAO

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 778-783 doi: 10.1007/s11783-012-0434-7

摘要： The abiotic association between phthalic acid esters (PAEs) and humic substances (HS) in sludge landfill plays an important role in the fate and stability of PAEs. An equilibrium dialysis combined with C-labeling was used to study the abiotic association of two abundant PAEs (diethyl phthalate and di- -butyl phthalate) with humic acid (HA) isolated from a sludge landfill with different stabilization times and different molecular weights. Elemental analysis and Fourier Transform Infrared Spectrophotometer (FTIR) suggested that high value of HA was related to the high aromatic content and large molecular weight of HA. The results indicated that the association strength of PAEs with HA depended on both the properties of the PAEs and the characteristics of HA. The values of the association were strongly dependent on solution pH, and decreased dramatically as the pH was increased from 3.0 to 9.0. The results suggested that non-specific hydrophobic interaction between PAEs and HA was the main contributor to the association of the PAEs with HA. The interactive hydrogen-bonds between the HA and the PAEs molecules may also be involved in the association.

关键词： abiotic association     phthalic acid esters (PAEs)     humic acid     sludge     landfill    

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Optimization of pretreatment of Jatropha oil with high free fatty acids for biodiesel production

Supriyono SUWITO, Giuliano DRAGONE, Hary SULISTYO, Bardi MURACHMAN, Suryo PURWONO, José TEIXEIRA

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 210-215 doi: 10.1007/s11705-012-1282-5

摘要： A central composite rotatable design and response surface methodology were used in order to investigate the individual and combined effects of the ethanol-to-oil ratio, H SO concentration, temperature and time of reaction on the reduction of free fatty acid (FFA) in jatropha oil. A quadratic polynomial model relating the reaction variables with FFA reduction was developed, presenting a good coefficient of determination ( = 0.893). For reducing FFA to less than 1%, the optimal combination was found to be 0.62 v·v ethanol-to-oil ratio (14.9 v·v ethanol-to-FFA ratio), 1.7% v·v H SO concentration, and 79 min reaction time at a reaction temperature of 54°C. These results are of great relevance to maximize methyl esters formation by transesterification using an alkaline catalyst.

关键词： biodiesel     biofuel     esterification     free fatty acids     jatropha curcas oil    

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Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative couplingof benzoic acids using sodium chlorite as oxidant

Yun Liu, Youquan Zhu, Chaojun Li

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 3-8 doi: 10.1007/s11705-017-1693-4

摘要： A mild and efficient synthesis for the biaryl acids via rhodium-catalyzed cross-dehydrogenative coupling reaction has been developed. This novel protocol with sodium chlorite as an oxidant featured many advantages such as mild reaction conditions, high regioselectivity, tolerance of various functional groups, and good to excellent yields.

关键词： biaryl acids     cross-dehydrogenative coupling     rhodium-catalyzed    

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标题 作者 时间 类型 操作

Effects of oxidizing environment on digestate humification and identification of substances governing the dissolved organic matter (DOM) transformation process

期刊论文

Variation in humic and fulvic acids during thermal sludge treatment assessed by size fractionation, elementary

Yuning YANG,Huan LI,Jinyi LI

期刊论文

Effects of water quality on the coagulation performances of humic acids irradiated with UV light

Wendong WANG,Qinghai FAN,Zixia QIAO,Qin YANG,Yabo WANG,Xiaochang WANG

期刊论文

Effect of metal ion-doping on characteristics and photocatalytic activity of TiO

Rongfang YUAN,Beihai ZHOU,Duo HUA,Chunhong SHI

期刊论文

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

期刊论文

Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate

期刊论文

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

期刊论文

Electrochemical oxidation of humic acid at the antimony- and nickel-doped tin oxide electrode

TANG Chengli,YAN Wei,ZHENG Chunli

期刊论文

Effects of humic acid on residual Al control in drinking water treatment plants with orthophosphate addition

Wendong WANG, Hua LI, Zhenzhen DING, Xiaochang WANG, Rui LIU

期刊论文

Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

期刊论文

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

期刊论文

Characterization of soil low-molecular-weight organic acids in the Karst rocky desertification region

Xiaoliang LI, Xiaomin CHEN, Xia LIU, Lianchuan ZHOU, Xinqiang YANG

期刊论文

Abiotic association of phthalic acid esters with humic acid of a sludge landfill

Xiaoli CHAI, Yongxia HAO, Xin ZHAO, Guixiang LIU, Ying ZHU, Rong JI, Jun WU, Huanhuan TONG, Youcai ZHAO

期刊论文

Optimization of pretreatment of Jatropha oil with high free fatty acids for biodiesel production

Supriyono SUWITO, Giuliano DRAGONE, Hary SULISTYO, Bardi MURACHMAN, Suryo PURWONO, José TEIXEIRA

期刊论文

Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative couplingof benzoic acids using sodium chlorite as oxidant

Yun Liu, Youquan Zhu, Chaojun Li

期刊论文