JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Wenjing Yan,Bin Liang,Wanhe Li,Hualin Huang,Deqiang Shi,Zhenming Chen,Zhongmin Li,Meihua Yu,Guangtao Wei,Kai Huang
The formation of vaterite is well known to be influenced by many low molecular weight additives. In this study, Density functional theory calculations was employed to study the effect of biological material lysine(Lys), aspartic acid(Asp), threonine(Thr) and glycine(Gly) on the formation of vaterite CaCO 3 . The interaction energies between Gly and CaCO 3 (110) and (104) surfaces were −2.618 and −1.784 eV, respectively. With the molar ratio of Ca 2+ to Gly at 1.5, the reaction time of 11.5 min, the pH value of 7.5, the crystalline product of the reaction was almost monodisperse spherical vaterite in Ca(OH) 2 -Gly-CO 2 reaction system. The obtained products were characterized by the XRD, RAM, SEM, TEM, and FT-IR. The results showed that the increase of Gly concentration inhibited the nucleation and the growth of calcite. Lys, Asp, Thr and Gly were employed as stabilizers for controlling particles, the crystalline product of the reaction was almost monodisperse vaterite CaCO 3 . Its surface chemistry can be explored using this mechanism analysis. The methods are expected to be a reference for industrial production process.
研究领域:
材料科学
·
生物化学
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产品关联
DOI
高影响因子
Food Bioscience
·
2025
·
IF 5.9
Lin Yuan,Yunjie Li,Liuyan Zheng,Yifan Qin,Xin Zhang,Lijuan Ma,Huan Zhang,Liping Du
Organic acids are critical flavor contributors in light-flavor Baijiu (LFB). The binding of organic acids and volatile compounds may affect the release of flavor in Baijiu. In this study, the effects of different concentrations of lactic acid, hexanoic acid, butyric acid, and acetic acid on the release of key aroma-active compounds in LFB were investigated. Twenty volatile compounds were identified as key aroma-active compounds in four LFB samples using odor activity values combined with aroma recombination, and omission experiment methods. Furthermore, as the concentrations of organic acids were increased in the simulated LFB solution, significant changes in the release of key aroma-active compounds occurred. The addition of lactic acid from 0.5-fold to 5-fold resulted in all key aroma-active compounds exhibiting stronger releases, especially the addition of a 3-fold concentration of lactic increased the release of key esters to about twice. In contrast, the effect of hexanoic acid, butyric acid, and acetic acid on the release of key aroma-active compounds showed a concentration-dependent trend. This suggests that the specific structures of volatiles and organic acids alter the intermolecular interactions between them, thereby altering the aroma release. The results reveal that different organic acids alter the overall aroma profile by affecting the release of volatile compounds in the LFB matrix.
研究领域:
食品科学
·
化学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2014
·Vol. 17
·期 1
·453-459
·
IF 6.852
Muge Niu,Yucui Hou,Shuhang Ren,Weize Wu,Kenneth N. Marsh
Formic acid (FA) is an important material widely used in the chemical industry and in processes involved in energy storage and transformation. In this work, production of FA from wheat straw, an abundant lignocellulosic biomass, in NaVO3–H2SO4 aqueous solution with molecular oxygen (O2) was studied. The conversion showed high efficiencies: 47% (based on carbon, 75.2% based on mass) of FA and 7.3% (based on carbon, 7.6% based on mass) of acetic acid were obtained. The products mainly come from polysaccharides (hemicellulose and cellulose) in wheat straw. Acetic acid is derived from the acetyl groups in (1) the hemicellulose structure or (2) the deep hydrolysis product, levulinic acid. The removal of each lignocellulosic component in wheat straw follows the order: hemicellulose, lignin and cellulose. The catalytic system shows good reusability, and multiple feedings led to a high concentration of FA, which is beneficial to reduce FA–water separation cost.
研究领域:
生物化学
·
可再生能源
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Yangyi Huang,Lin Zhang,Mengqi Yan,Qinan Huang,Yuning Zhang,Yanqun Ren,Weiping Luo
In this research, the solubilities of adipic acid in sec-butyl alcohol (SBA), isobutyl alcohol (IBA), and n-octyl alcohol (NOA); glutaric acid in n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, SBA, IBA, tert-butyl alcohol (TBA), and NOA; and succinic acid in SBA, IBA, TBA, and NOA were determined by the dynamic laser method from 302.65 to 352.95 K at atmospheric pressure (101.3 kPa). Furthermore, the solubilities of three dibasic acids in straight-chain alcohols of different lengths and alcohol isomers were compared. Meanwhile, X-ray diffraction was used to detect the change of the crystal form before and after dissolution. Additionally, the experimental data were correlated by two models (Apelblat model and the modified nonrandom two liquid activity coefficient model), showing that the model matched well with the experimental data. The most accurate model is selected for every system after calculating the Akaike information criterion of each model.
研究领域:
物理化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Qiuyue Wang,George Q. Chen,Lin Lin,Xiaoyan Li,Sandra E. Kentish
The feasibility of using electrodialysis with bipolar membranes (EDBM), combined with monovalent selective anion exchange membranes was investigated to purify organic acids from fermentation broths or wastewater streams. A simulated beet molasses feed containing a mixture of monobasic lactic acid and polybasic citric acid was used for this purpose. The impact of the feed pH, the configuration of the membrane stack and the voltage applied on the selectivity of the process was investigated. At a pH of 9–10 and an electric field intensity of 9 V/cm, a lactic acid product with a purity of at least 97% can be obtained by using both two chamber (BP-A) and three chamber (BP-A-C) configurations with the monovalent selective membrane. When using the BP-A configuration, the hydroxide ions generated by the bipolar membrane compete with the lactate anions to move into the acid solution and so the energy efficiency is lower than with the BP-A-C configuration. To mimic a multiple pass process and increase the lactic acid concentration of the final product, experiments were performed across a range of volume ratios between the feed and acid solutions. As this ratio is varied, the purity of lactic acid produced remains higher than 95% while the energy consumption is essentially unaffected. Due to the osmotic flow of water during experiments, the highest lactic acid concentration that can be achieved is limited to 153 g/L at a volume ratio (V A : V F ) of 1:10.
研究领域:
生物工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Yifei Zhang,Zhechao Hua,Xuewen Zhang,Kaiheng Guo,Jingyun Fang
Solar photolysis of free chlorine (solar/chlorine) in bromide-containing water occurs under various scenarios, such as chlorinated reservoirs and outdoor swimming pools, and the formation of chlorate and bromate is an important issue in the system. We reported unexpected trends for the formation of chlorate and bromate in the solar/chlorine system. Excess chlorine inhibited the formation of bromate, i.e., increasing chlorine dosages from 50 to 100 μM reduced the bromate yield from 6.4 to 1.2 μM in solar/chlorine at 50 μM bromide and pH 7. The yield of bromate in solar/chlorine at 100 μM chlorine and 50 μM bromide in 240 min was 18.8% of that at 50 μM bromine only. The underlying mechanism was that HOCl can react with bromite (BrO 2 − ) to form HOClOBrO − , whose multi-step transformation finally formed chlorate as the major product and bromate as the minor product. This reaction overwhelmed the oxidation of bromite to form bromate by reactive species, such as • OH, BrO • and ozone. On the other hand, the presence of bromide greatly enhanced the formation of chlorate. Increasing bromide concentrations from 0 to 50 μM enhanced the chlorate yields from 2.2 to 7.0 μM at 100 μM chlorine. The absorbance of bromine was higher than that of chlorine, thus the photolysis of bromine formed higher levels of bromite at higher bromide concentrations. Then, bromite rapidly reacted with HOCl to form HOClOBrO − and it further transformed to chlorate. Additionally, 1 mg L − 1 NOM had a negligible effect on bromate yields in solar/chlorine at 50 μM bromide, 100 μM chlorine and pH 7. This study demonstrated a new pathway of chlorate and bromate formation in the solar/chlorine system with bromide.
研究领域:
环境科学
·
化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Weiping Luo,Mengqi Yan,Bao Tao,Sile Shi,Bo Chen
The solubilities of succinic acid, glutaric acid and adipic acid in propionic acid + water solvent mixtures at 304.25–354.65 K, and in propionic acid + ε-caprolactone + water solvent mixtures at 297.65–351.25 K were determined by the synthetic method at atmospheric pressure. The experimental data in propionic acid + water solvent mixtures were correlated by the modified Apelblat equation and modified nonrandom two-liquid (NRTL) activity coefficient model. The results showed that the calculated solubility data by the modified NRTL models had a better agreement with the experimental data, and the value of average relative deviation was 1.923%. And the solubilities of succinic acid, glutaric acid and adipic acid in ternary propionic acid + ε-caprolactone + water solvent mixtures predicted by the modified NRTL model agree with the experimentally determined results satisfactorily, which showed that the modified NRTL model would be suitable model for predicting the solubilities of succinic acid, glutaric acid and adipic acid in propionic acid + ε-caprolactone + water. Furthermore, the thermodynamic functions including dissolution enthalpy, entropy and Gibbs energy were obtained from the solubility data by using the van't Hoff equation.
研究领域:
化学工程
·
物理化学
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产品关联
DOI
高影响因子
CELLULOSE
·
2017
·Vol. 25
·期 1
·205-216
·
IF 3.417
Xu Qinqin,Song Longchu,Zhang Lihua,Hu Gang,Chen Qin,Liu Enhui,Liu Yu,Zheng Qiang,Xie Haibo,Li Nanwen
The reversible reaction of the hydroxyl groups in cellulose with CO 2 in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) results in a rapid and effective derivative dissolution of cellulose in DMSO, by which a series of cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) with various degrees of substitution (DS) were synthesized controllably without adding external catalysts. Wherein DBU not only achieves the dissolution of cellulose, but also acts as an efficient organocatalyst for the subsequent cellulose derivatization. The DS of CAB and CAP can be tuned by changing the feed molar ratio of propionic (butyric) anhydride/acetic anhydride and the reaction temperature. The structural and thermal properties of the products were characterized by several analytical techniques including NMR, FT-IR, and TGA. The CO 2 /DBU/DMSO dissolution system provides a new platform for controllable synthesis of mixed cellulose esters with high efficiency under mild conditions.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2023
·
IF 11.4
Lijuan Wu,Rui Zhu,Xiaoxia Han,Yan Chen,Zhen Long,Hao Dong,Xiaojiang Chen,Yang Wu,Yinglong Su,Zhengyong Zhang,Jingyang Luo
Anaerobic fermentation is a promising method for waste activated sludge (WAS) treatment, but ineffective solubilization and hydrolysis limit its application. The current study examined the function of sodium sulfite (SDS) in potassium permanganate (PP)-conditioned WAS fermentation for short-chain fatty acids (SCFAs) biosynthesis . The presence of SDS in the PP system (PP/SDS) reduced the positive effects of PP on total SCFAs yield (2755 versus 3471 mg COD/L), while effectively increasing the proportion of acetate (from 41 to 81 %). Not only did SDS decrease the promoting effects of PP on WAS solubilization and hydrolysis efficiency by 5–42 %, it also shifted microbial metabolic pathways to favor acetate production. In addition, the amino acid metabolism with acetate as end product was enhanced. Moreover, PP/SDS inhibited methanogenesis, resulting in an accumulation of acetate in high quantities. Thus, the current study a provided insight and direction for effective WAS treatment with acetate-enriched SCFAs production.
研究领域:
环境科学
·
微生物学
·
废水处理工程
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产品关联
DOI
PubMed
高影响因子
PLoS One
·
2024
·Vol. 19
·期 4
·e0299218
·
IF 2.9
Zhonglei Meng,Rongxiu Qin,Rusi Wen,Junkang Xie,Guiqing Li,Yonghong Zhou
To enhance the yield of the one-step synthesis of terpinyl acetate from α-pinene and acetic acid, this study evaluated α-hydroxycarboxylic acid (HCA)–boric acid composite catalysts based on orthogonal experimental design. The most important factor affecting the terpinyl acetate content in the product was the HCA content. The catalytic performance of the composite catalyst was related to the pKa1 of HCA. The tartaric acid–boric acid composite catalyst showed the highest catalytic activity. The α-pinene conversion reached 91.8%, and the terpinyl acetate selectivity reached 45.6%. When boric acid was replaced with B2O3, the HCA composite catalyst activity was enhanced, which reduced the use of HCA. When the lactic acid and B2O3 content accounted for 10% and 4% of the α-pinene mass content, respectively, the α-pinene conversion reached 93.2%, and the terpinyl acetate selectivity reached up to 47.1%. In addition, the presence of water was unfavorable to HCA–boric acid composite catalyst. However, a water content less than 1% of the α-pinene mass content improved the catalytic activity of HCA–B2O3. When the tartaric acid–B2O3 was used as catalyst, and the water content was 1% of the α-pinene mass content, the α-pinene conversion was 89.6%, and the terpinyl acetate selectivity was 47.5%.
研究领域:
化学工程
·
催化
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Xiao-Guo Ji,Kun-Lin Chang,Mai Chen,Liang-Liang Zhu,Arwa Osman,Hao Yin,Li-Ming Zhao
Chitooligosaccharides (COS), with a specific degree of polymerization, were evaluated for their effect on human fecal microbiota, as well as their metabolite, using an in vitro anaerobic batch fermentation model. COS increased the richness and diversity of the gut microbial community. More importantly, the microbial community structure of the COS groups was significantly different from the control and fructooligosaccharides (FOS) groups. COS specifically enriched the butyric and propionic acid-producing microbiota and targeted Faecalibacterium , Clostridium_sensu_stricto_1 , C._sensu_stricto_13 , and Fusicatenibacter . Furthermore, COS increased the acetic, propionic, and butyric acid contents. The production of propionic acid was greater than that obtained using FOS. Metabolome analysis suggested that COS could upregulate allocholic acid, 1,3-butanediol, 3,4-dihydroxybutanotic acid, and 2-hydroxybutyric acid production and downregulate putrescine, ethanamine, hexanoic acid, and branched chain amino acid ( l -valine and l -leucine) production in the fermentation broth. These differential metabolites were closely related to lipid, glucose, and amino acid metabolism. These results should inform further development of COS as potential raw materials for functional foods and health products.
研究领域:
微生物学
·
营养学
·
胃肠病学
·
食品科学
·
代谢组学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Biobased Materials and Bioenergy
·
2012
·Vol. 6
·期 2
·178-184
·
IF 1.037
Li Xian-Fa,Fu Yao
A solid acid catalyst KLC-SO3H bearing SO3H, COOH and phenolic OH groups was synthesized by the sulfonation of industrial waste kraft kraft lignin-based activated carbon (KLC) which was prepared from phosphoric acid (PA) activation. The KLC support and the catalyst
were characterized by a variety of techniques. The prepared catalyst exhibits good activity to catalyze the esterification of oleic acid with methanol. Yield of methyl oleate as high as 93.2% was obtained under the temperature of 80 °C, methanol to oleic acid molar ratio of 10:1, reaction
time of 12 h and catalyst loading of 10% (based on oleic acid). The prepared KLC-SO3H catalyst showed similar catalytic activity with the carbon acid catalyst from cellulose and the commercial catalyst Amberlyst-15 in the esterification reaction. The high catalytic activity of KLC-SO3H
was probably due to the large specific surface area, pore volume of KLC support, which provided more acid sites for the reactants.
研究领域:
化学工程
·
催化材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）