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Haloacetic acids in swimming pool and spa water in the United States and China

Xiaomao WANG,Garcia Leal M I,Xiaolu ZHANG,Hongwei YANG,Yuefeng XIE

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 820-824 doi: 10.1007/s11783-014-0712-7

摘要： The objective of this study is to investigate the occurrence of haloacetic acids (HAAs), a group of disinfection byproducts, in swimming pool and spa water. The samples were collected from six indoor pools, six outdoor pools and three spas in Pennsylvania, the United States, and from five outdoor pools and nine indoor pools in Beijing, China. Five HAAs (HAA5), including monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid were analyzed. Total chlorine, pH and total organic carbon concentration were analyzed as well. Results indicated that the levels of HAA5 in swimming pools and spas in the United States ranged from 70 to 3980 μg·L , with an arithmetic average at 1440 μg·L and a median level at 1150 μg·L . These levels are much higher than the levels reported in chlorinated drinking water and are likely due to organic matters released from swimmers’ bodies. The levels of HAA5 in swimming pools in China ranged from 13 to 332 μg·L , with an arithmetic average at 117 μg·L and a median level at 114 μg·L . The lower HAA levels in swimming pools in China were due to the lower chlorine residuals. Results from this study can help water professionals to better understand the formation and stability of HAAs in chlorinated water and assess risks associated with exposures to HAAs in swimming pools and spas.

关键词： chlorination     disinfection byproduct     haloacetic acid     swimming pool     trihalomethane    

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Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional stimulants

Alvyn P. Berg, Ting-An Fang, Hao L. Tang

《环境科学与工程前沿（英文）》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1098-3

摘要：

• Swimming pool water was studied for DBPs upon exposure to additional stimulants.

• DBP formation could be induced by residual chlorine and extended incubation.

• Urine led to a massive formation of chloroform with additional stimulants.

• Reactions between chlorine and anthropogenic organics were slow and long-lasting.

• Urine control and air ventilation should be on the priority list for pool management.

关键词： Trihalomethanes     Haloacetic acids     Chloroform     Residual chlorine     Anthropogenic organics     Swimming pool water    

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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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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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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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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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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 organic acids on Cd adsorption and desorption by two anthropic soils

Jingui WANG, Jialong LV, Yaolong FU

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 19-30 doi: 10.1007/s11783-012-0424-9

摘要： The objective of this experiment was to study the effects of malic, tartaric, oxalic, and citric acid on the adsorption and desorption characteristics of Cd by two typical anthropic soils (lou soil and irrigation-silted soil) in North-west China. Cadmium adsorption and desorption were studied under a range of temperatures (25°C, 30°C, 35°C, 40°C), organic acid concentrations (0.5–5.0 mmol·L ), and pH values (2–8). The results showed that the Cd adsorption capacity of the lou soil was significantly greater than that of the irrigation-silted soil. Generally, Cd adsorption increased as the temperature increased. In the presence of NaNO , the adsorption of Cd was endothermic with Δ values of 31.365 kJ·mol for lou soil and 28.278?kJ·mol for irrigation-silted soil. The endothermic reaction indicated that H bonds were the main driving force for Cd adsorption in both soils. However, different concentrations of organic acids showed various influences on the two soils. In the presence of citric acid, chemical adsorption and van der Waals interactions were the main driving forces for Cd adsorption rather than H bonds. Although the types of organic acids and soil properties were different, the effects of the organic acids on the adsorption and desorption of Cd were similar in the two soils. The adsorption percentage of Cd generally decreased as organic acid concentrations increased. In contrast, the adsorption percentage increased as the pH of the initial solution increased. The exception was that adsorption percentage of Cd increased slightly as oxalic acid concentrations increased. In contrast, the desorption percentage of Cd increased with increasing concentrations of organic acids but decreased as the initial solution pH increased.

关键词： adsorption     desorption     cadmium     organic acids     temperature     anthropic soil    

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Insights into the changes of amino acids, microbial community, and enzymatic activities related with

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1635-y

摘要：

● The highest seed germination index was achieved at 0.3 g/g total solids of food waste.

关键词： Composting     Food waste     Amino acids     Microbial community     Enzymatic activity     Nutrient quality    

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Perfluorocarboxylic acids (PFCAs) and perfluoroalkyl sulfonates (PFASs) in surface and tap water around

Yong QIU, He JING, Hanchang SHI,

《环境科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 301-310 doi: 10.1007/s11783-010-0236-8

摘要： Perfluorinated compounds (PFCs) are ubiquitously distributed in the environment mainly as perfluoro-carboxylic acids (PFCAs) and perfluoroalkyl sulfonates (PFASs). In this paper, six PFCAs and two PFASs were quantified in surface and tap water samples from 12 sites around Lake Taihu near Shanghai City in East China. Predominant PFCs were perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), of which the concentration ranges were 6.8–206 and 1.2–45 ng·L, the geometric means were 35.3 and 9.4 ng·L, and the median (quartile range) values were 31.4 (34.4) and 10.4 (10.7) ng·L, respectively. Other PFCs were also detected but in much lower concentrations than PFOA. The sources of the PFCs were expected to be direct industrial discharges in the Lake Taihu area, and this area was also a possible source of PFCs contaminations in Shanghai district in the downstream. PFCs distributions were found different in the upstream, downstream and north part of Lake Taihu. Occurrences of PFCs in the tap water in Lake Taihu area indicated their exposure to the local people. A brief estimation of the environmental risks by PFCs implied no acute or immediate risks from PFCs to local human health, but chronic risks from PFOA in the tap water should be considered in the downstream regions.

关键词： surface and tap water     perfluorocarboxylic acids (PFCAs)     perfluoroalkyl sulfonates (PFASs)     Lake Taihu area     ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS)    

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Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effect

Leiyu FENG, Yuanyuan YAN, Yinguang CHEN

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 623-632 doi: 10.1007/s11783-011-0334-2

摘要： Effect of pH ranging from 4.0 to 11.0 on co-fermentation of waste activated sludge (WAS) with food waste for short-chain fatty acids (SCFAs) production at ambient temperature was investigated in this study. Experimental results showed that the addition of food waste significantly improved the performance of WAS fermentation system, which resulted in the increases of SCFAs production and substrate reduction. The SCFAs production at pH 6.0, 7.0, 8.0, and 9.0 and fermentation time of 4 d was respectively 5022.7, 6540.5, 8236.6, and 7911.7 mg COD·L , whereas in the blank tests (no pH adjustment, pH 8.0 (blank test 1), no food waste addition, pH 8.0 (blank test 2), and no WAS addition (blank test 3)) it was only 1006.9, 971.1, and 1468.5 mg COD·L , respectively. The composition of SCFAs at pH from 6.0 to 9.0 was also different from other conditions and propionic acid was the most prevalent SCFA, which was followed by acetic and n-butyric acids, while acetic acid was the top product under other conditions. At pH 8.0 a higher volatile suspended solids (VSS) reduction of 16.6% for the mixture of WAS and food waste than the sole WAS indicated a synergistic effect existing in fermentation system with WAS and food waste. The influence of pH on the variations of nutrient content was also studied during anaerobic fermentation of the mixture of WAS and food waste at different pH conditions. The release of increased with fermentation time at all pH values investigated except 4.0, 5.0 and in blank test one. The concentrations of soluble phosphorus at acidic pHs and in the blank test one were higher than those obtained at alkaline pHs. Ammonia and phosphorus need to be removed before the SCFAs-enriched fermentation liquid from WAS and food waste was used as the carbon source.

关键词： waste activated sludge (WAS)     food waste     co-fermentation     short-chain fatty acids (SCFAs)     pH     synergistic effect    

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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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A new method for the synthesis of molybdovanadophosphoric heteropoly acids and their catalytic activities

ZHANG Fumin, GUO Maiping, GE Hanqing, WANG Jun

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 296-299 doi: 10.1007/s11705-007-0054-0

摘要： An environmentally benign method for the synthesis of heteropoly acids HPMoVO·HO (PMoV, = 1−3) was developed by the reaction of an aqueous slurry which contained stoichiometric amounts of MoO, VO and HPO. Characterization of the as-synthesized catalysts with inductively coupled plasma (ICP) elemental analysis, thermogravimetry (TG), X-ray diffraction (XRD) and infrared (IR) spectroscopy indicated that V ions substituted for Mo ions in Keggin-type phosphomolybdic acid. The as-synthesized samples were found to be an efficient catalyst for the hydroxylation of benzene which was carried out in a mixed solvent of acetonitrile and acetic acid with aqueous hydrogen peroxide as oxidant. PMoV exhibi ted the highest benzene conversion of 34.5% with phenol selectivity of 100%.

关键词： conversion     heteropoly     Characterization     efficient catalyst     Keggin-type phosphomolybdic    

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标题 作者 时间 类型 操作

Haloacetic acids in swimming pool and spa water in the United States and China

Xiaomao WANG,Garcia Leal M I,Xiaolu ZHANG,Hongwei YANG,Yuefeng XIE

期刊论文

Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional stimulants

Alvyn P. Berg, Ting-An Fang, Hao L. Tang

期刊论文

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

期刊论文

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

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

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

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 organic acids on Cd adsorption and desorption by two anthropic soils

Jingui WANG, Jialong LV, Yaolong FU

期刊论文

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

期刊论文

Perfluorocarboxylic acids (PFCAs) and perfluoroalkyl sulfonates (PFASs) in surface and tap water around

Yong QIU, He JING, Hanchang SHI,

期刊论文

Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effect

Leiyu FENG, Yuanyuan YAN, Yinguang CHEN

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

A new method for the synthesis of molybdovanadophosphoric heteropoly acids and their catalytic activities

ZHANG Fumin, GUO Maiping, GE Hanqing, WANG Jun

期刊论文