JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Yina Sun,Guangwen Li,Kangfei Lu,Xingchuan Yang,Li Xu,Guoji Liu,Yi Yu
Solubility data and regularity of 3-methyl-1,2-cyclopentanedione (MCP) in twelve pure organic solvents were investigated by static method under certain conditions. The results of experiments demonstrate that the solubility of MCP is proportional to the temperature. One of the most solubilizing solvents is dichloromethane. A preliminary assessment of the potential for chemical bond formation between the solute and the solvent was conducted by examining electrostatic potential energy surfaces of the solute. The dissolution behavior was explained by physicochemical properties (polarity, hydrogen bond donor–acceptor propensities and cohesive energy density (CED)) of solvent. The results demonstrate that polarity has a more pronounced impact on the dissolution process, but that other properties also effect the dissolution process to some extent. The Density Functional Theory (DFT) was applied to demonstrate interactions between solute and solvent during the dissolution process. Six thermodynamic models (van’t Hoff, Apelblat, Yaws, λh , Wilson, Jouyban) were utilized to fit solubility data. Wilson model exhibits the highest correlation. The thermodynamic properties indicate that the dissolution of the MCP can be described as an entropy-driven process, which is endothermic and spontaneous.
研究领域:
物理化学
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材料科学
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DOI
高影响因子
VACUUM
·
2024
·
IF 3.8
Kaile Shi,Haodong Zheng,Yuze Sun,Honghai Wang,Jing Fang,Chunli Li,Jiapeng Liu
The utilization of 1,4-butanediol (BDO) spans across numerous sectors, underscoring its significance as a pivotal chemical. However, the separation of crude BDO still presents great challenges. Ethylene glycol (EG) and 3-methyl-1,5-pentanediol (MPD) are classical impurities in BDO crude products. In this paper, the pressure and temperature data of MPD components under high vacuum pressure were measured, and Antoine constant was obtained by fitting to supplement the basic data. The isobaric vapor-liquid equilibrium (VLE) data for the EG-BDO and BDO-MPD mixtures were experimentally measured at pressures of 1.0, 10.0, and 50.0 kPa. Meanwhile, the thermodynamic consistency of the experimental binary data was examined using the Herington area test. The experimental VLE data for binary systems were analyzed using the nonrandom two-liquid (NRTL) universal quasichemical (UNIQUAC) and Wilson activity coefficient models, demonstrating that the predicted outcomes showed excellent agreement with the measured data. Finally, the interaction energy between the components was calculated by molecular simulation to explain the gas-liquid equilibrium behavior. Therefore, this work provided guidance and basis for the separation of EG-BDO and BDO-MPD in high vacuum separation.
研究领域:
化学工程
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物理化学
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DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2020
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IF 2.888
Xingchuan Yang,Huanxin Li,Chunmei Cao,Li Xu,Guoji Liu
Liquid-liquid equilibria (LLE) data for ternary systems of water + 1,6-hexanediol + 1-pentanol/ 3-methyl-1-butanol/ 2-methyl-2-butanol were measured at (293.15, 303.15, 313.15 and 323.15) K under 101.3 kPa. Cloud-point method was applied to determine the solubility curves data. Distribution coefficient and separation factors for 1,6-hexanediol were calculated from the measured tie-line data to evaluate the extraction effect of alcohols on 1,6-hexanediol. The reliability of experimental LLE data were tested by Othmer–Tobias equation and Hand equation, NRTL and UNIQUAC models were applied to correlate the measured data and the calculated results show that both models can fit the experimental data very well.
研究领域:
化学工程
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热力学
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2024
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IF 6.7
Jijuan Zhou,Dianlong Ge,Yue Liu,Yajing Chu,Xiangxue Zheng,Yan Lu,Yannan Chu
Cellular volatile organic compound (VOC) detection is crucial for studying lung cancer biomarkers. However, the reported VOC biomarkers from the same cell line seem to be inconsistent across different research groups. It is possibly related to the variation in culture media, and the result obtained by a conventional single medium approach (SMA) depends on what medium is used in the cell experiment. This study proposes a multiple media approach (MMA) to investigate reproducible characteristic VOCs of lung cancer cells. Using solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) in combination with untargeted analysis, we conducted two independently repetitive experiments to compare lung cancer cells (A549) and normal lung cells (BEAS-2B) under three culture media conditions (RPMI 1640, DMEM, and Ham’s F12). Both experiments indicated that, compared with 62–96 VOCs obtained by the SMA, only two VOCs (3-methyl-1-butanol and 2-methyl-1-butanol) were reproducibly achieved by the MMA. Moreover, their concentrations were significantly lower in lung cancer cells than in normal cells. Further targeted analysis confirmed the downregulation trend of both VOCs in subcutaneous and primary tumor tissues from the lung cancer model mouse. The present work demonstrated that the MMA cell experiment, just like the multicenter trials for cell lines, can facilitate the discovery of reproducible characteristic VOCs. This provides a cellular experimental basis and scientific evidence for lung cancer biomarker investigation and even breath biopsy technique development.
研究领域:
医学
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分析化学
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肿瘤学
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产品关联
DOI
PubMed
高影响因子
ACS Catalysis
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2016
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IF 9.307
Zhixin Zhang,Yehong Wang,Jianmin Lu,Chaofeng Zhang,Min Wang,Mingrun Li,Xuebin Liu,Feng Wang
Conversion of low-carbon olefins to higher alcohols or olefins via the formation of C–C bonds is an increasingly important topic. We herein report an example of converting isobutene and formaldehyde (38 wt % aqueous solution) to 3-methyl-1,3-butanediol (MBD), a precursor for isoprene. The reaction occurs through a Prins condensation–hydrolysis reaction over a praseodymium (Pr)-doped CeO2 catalyst. The best MBD yield (70%) is achieved over the Pr-doped CeO2 catalyst. Catalyst characterizations with high-angle annular dark field transmission electron microscopy (HAADF-TEM), pyridine adsorption infrared (IR) and Raman spectroscopy, and density functional theory (DFT) calculations show that the doped Pr is uniformly and highly dispersed in the CeO2 crystalline phase. In addition, the Pr doping creates more oxygen vacancy sites on CeO2 and thus enhances the Lewis acidity of the catalyst, which is responsible for the catalytic performance of the Pr-CeO2 catalyst.
研究领域:
催化化学
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材料科学
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有机合成
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DOI
高影响因子
BIOCHEMICAL GENETICS
·
2019
·Vol. 57
·期 3
·443-454
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IF 1.931
Zhang Yu,Zhang Xiaohuan,Xiao Shiyuan,Qi Wei,Xu Jingliang,Yuan Zhenhong,Wang Zhongming
3-Methyl-1-butanol (3MB) is a promising biofuel that can be produced from 2-ketoisocaproate via the common l -leucine biosynthesis pathway. Corynebacterium glutamicum was chosen as a host bacterium because of its strong resistance to isobutanol. In the current study, several strategies were designed to overproduce 3MB in C. glutamicum through a non-fermentation pathway. The engineered C. glutamicum mutant was obtained by silencing the pyruvate dehydrogenase gene complex ( aceE ) and deleting the lactic dehydrogenase gene ( ldh ), followed by mutagenesis with diethyl sulfate (DES) and selection with Fmoc-3-4-thiazolyl- l -alanine (FTA). The mutant could produce 659 mg/L of 3MB after 12 h of incubation. To facilitate carbon flux to 3MB biosynthesis, the engineered recombinant was also constructed without branched-chain acid aminotransferase ( ilvE ) activity by deleting the ilvE gene. This recombinant could produce 697 mg/L of 3MB after 12 h of incubation.
研究领域:
微生物学
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生物技术
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代谢工程
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DOI
PubMed
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 9
·e202203332
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IF 2.1
Cunwei Qian,Ying Wang,Xian Li,Changsheng Yao
Graphical A convenient, rapid and electrochemical one-pot protocol is designed for the synthesis of pyrazolo[3,4- b ]quinolines derivatives. The reaction is carried out in an undivided cell equipped with an iron cathode and a graphite anode in the presence of sodium bromide as a supporting electrolyte. Fourteen pyrazolo[3,4- b ]quinoline derivatives are obtained under a constant current of 30 mA after 0.14 F/mol of electricity passed. A convenient, rapid and electrochemical one-pot protocol was developed successfully for the preparation of pyrazolo[3,4- b ]-quinoline derivatives. The reaction is carried out in a 25 mL three neck flask equipped with graphite electrode as anode and iron electrode as cathode (electrode area of 1 cm 2 ) with sodium bromide as supporting electrolyte at room temperature in ethanol. Fourteen pyrazolo-[3,4- b ]-quinoline derivatives were synthesized by use of various aldehyde (including aryl aldehydes and aliphatic aldehydes), dimedone and 5-amino-3-methyl-1-phenylpyrazole as substrates in good yields (76–86 %) with a constant current of 30 mA after 0.14 F/mol of electricity passed. All aimed products were characterized by IR, 1 H NMR and HRMS. Notably, the presented method features ecologically sound, simple experimental procedure and good yields.
研究领域:
有机化学
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电化学
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DOI
高影响因子
Journal of CO2 Utilization
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2022
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IF 8.321
Xiaowei Hu,Maowei Luo,Mooeez ur Rehman,Junhao Sun,Hamzah A.S.M. Yaseen,Faisal Irshad,Yujun Zhao,Shengping Wang,Xinbin Ma
The electron-donating effect of supports on active metals has been reported to be beneficial to improve catalytic activity of heterogenized molecule catalysts for CO 2 hydrogenation to formic acid . However, this effect has not been discussed in depth from the perspective of reaction mechanism, especially for CO 2 activation with the combination of theoretical calculations. Herein, we report a catalyst prepared via anchoring RuCl 3 on a post-synthetic modified (PSM) zeolitic imidazolate framework-8 (ZIF-8) in which linkers 3-methyl-1,2,4-triazole (Mtz) with a surplus of uncoordinated N sites have been incorporated. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations reveal that uncoordinated N sites in linkers donate additional electron-density to Ru, resulting in the decrease of energy barrier of CO 2 activation. And the RuCl 3 @ZIF-8-Mtz(0.29) catalyst containing the most Mtz ligands displayed the highest catalytic performance for the CO 2 hydrogenation to formic acid as compared to RuCl 3 @ZIF-8-Mtz(0.15) and RuCl 3 @ZIF-8.
研究领域:
催化
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材料科学
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化学工程
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理论化学
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产品关联
DOI
高影响因子
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