TALANTA
·
2017
·
IF 4.162
Rui Xiao,Xiaoting Zhang,Xiaona Zhang,Jiahua Niu,Minghua Lu,Xiuhua Liu,Zongwei Cai
In this article, a method for the analysis of flavors and fragrances including ethyl vanillin , trans-cinnamic acid, methyl cinnamate , ethyl cinnamate , and benzyl cinnamate in foods by HPLC with Fe 3 O 4 @GO nanocomposite as the adsorbent of magnetic solid-phase extraction was developed. The magnetic Fe 3 O 4 @GO nanocomposite was prepared and characterized by transmission electron microscope, infrared spectroscopy , X-ray diffraction and vibrating sample magnetometer. The as-prepared Fe 3 O 4 @GO nanocomposite was used as adsorbent for extraction and preconcentration of flavors and fragrances in foods. The extraction and desorption conditions including amount of materials, extraction time and desorption solvents were investigated. The analytes were separated within 10 min and detected with LODs ranged from 0.02 to 0.04 μg/mL. The recovery obtained from the analysis of spiked juice sample was between 71.5% and 112.4% with RSDs lower than 4.14%. The developed method was successfully applied to the analysis of real samples including orange juice, chocolate and fruit sugar.
研究领域:
分析化学
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食品科学
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产品关联
DOI
PubMed
高影响因子
Sustainable Chemistry and Pharmacy
·
2025
·
IF 5.8
Qingfen Zhang,Dan Ge,Shengcheng Mi,Qi Lu
The bioactive properties of essential oil are strongly associated with their chemical composition. In this work, a novel method of salt-enhanced homogenization pretreatment coupled with solvent-free microwave extraction (HP-SSFME) was developed for extracting essential oil (KGEO) from fresh Kaempferia galanga rhizomes, which significantly improved the extraction efficiency. Gas chromatography was employed to measure the contents of the main active components, ethyl p -methoxycinnamate (EPMC) and ethyl cinnamate (EC) in the essential oil. The extraction process was optimized by the Box-Behnken Design using the comprehensive scores of the yields of EPMC, EC, and KGEO obtained by the entropy weight method. The optimal parameters were determined as follows: amount of sodium chloride was 1.60 %, homogenization speed of 15000 r/min, homogenization time of 4 min, microwave irradiation power of 300 W, microwave irradiation time of 23 min. Under these conditions, the KGEO yield was 5.10 %, EPMC yield was 3.81 %, EC yield was 0.89 %. Compared with the conventional methods, the HP-SSFME method not only significantly increased the extraction yield of KGEO but also remarkably enhanced the yields of EPMC and EC. Additionally, the HP-SSFME method has low CO 2 emission and energy consumption, highlighting its environmental friendliness. Moreover, in terms of antibacterial activity, the HP-SSFME outperformed other methods, demonstrating a more powerful and extensive inhibitory effect against a range of bacteria. This study provides a valuable reference for the efficient extraction and quality control of essential oils from Kaempferia galanga rhizomes.
研究领域:
植物化学
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环境科学
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食品科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Linmao Tang,Yuan Guo,Zuoxiang Zeng,Weilan Xue
The density and liquid heat capacity of propyl cinnamate were measured in the temperature range from 290.15 to 503.15 K by a pycnometer and automatic adiabatic calorimeter and correlated with temperature by the linear equation and quadratic polynomial, respectively. Vapor pressure data of propyl cinnamate were determined by the ebulliometric method at 419.15–559.15 K, and they are in accordance with the Antoine equation. The vaporization enthalpy ΔvapH (Tb) of propyl cinnamate at normal boiling point was attained based on the Clausius–Clapeyron equation. The standard enthalpy of vaporization ΔvapH (298.15 K) was calculated by the Othmer method and verified by the Watson relation.
研究领域:
物理化学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2019
·
IF 2.298
Junshuai Chen,Ying Zhang,Taotao Zhan,Qi Zhou,Tian Lan,Maogang He
Methyl caprylate is expected to be one of the main components of biodiesel due to its high cetane number and good oxidation stability. Details of the experimental speeds of sound in methyl caprylate are very scarce, especially in high-temperature regions. Therefore, the speed of sound in liquid methyl caprylate was measured by the Brillouin light scattering method in the temperature range of 298.22–608.38 K and at pressures of up to 10 MPa. The relative expanded uncertainty of the speed of sound is estimated to be less than 1.32% (coverage factor k = 2). The variation of the speed of sound with the temperature and pressure was analyzed. Besides, the correlation for the speed of sound as a function of temperature and pressure is presented based on the experimental data. The absolute average of relative deviation between the experimental data and the calculated results is 0.29%.
研究领域:
物理化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2020
·Vol. 49
·期 9
·1237-1249
·
IF 1.273
Li Dan,Guo Meng,Wu Qian,Li Menglei,Ruan Nannan,Gao Lijun
The density, viscosity and excess properties of biodiesel–alcohol fuel blends are investigated for research into the blending of fuels. Four n -alkanols (1-propanol, 1-butanol, 1-pentanol and 1-hexanol) as additives were mixed with ethyl laurate to form binary systems for density and viscosity measurement. Excess molar volumes and viscosity deviations of the four binary systems (1-propanol + ethyl laurate), (1-butanol + ethyl laurate), (1-pentanol + ethyl laurate), and (1-hexanol + ethyl laurate) were calculated from the experimental density and viscosity data and fitted with the Redlich–Kister equation. Grunberg–Nissan and McAllister equations were used to correlate viscosities and the correlated values from McAllister equation are in good agreement with the experimental data. The results may be useful for the research and development of biodiesel–alcohol fuel blends.
研究领域:
能源科学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
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2023
·
IF 3.5
Ningrui Zhao,Jumei Xu,Zuoxiang Zeng,Weilan Xue
The density of (E)-isobutyl cinnamate at 297.95–535.20 K was measured using a capillary pycnometer and linearly related to temperature. The vapor pressure of (E)-isobutyl cinnamate at 420.15–570.05 K was measured by the ebulliometric method, and correlated by Antoine equation with an average relative deviation of 1.11 %. The vaporization enthalpy Δ vap H (T b ) of (E)-isobutyl cinnamate at normal boiling point was obtained based on the Clausius-Clapeyron equation. The standard vaporization enthalpy Δ vap H (298.15 K) was calculated to be 73.67±0.5 kJ·mol −1 by Othmer's method and verified by the Corresponding State Group Contribution (CSGC) method. The heat capacities at saturation vapor pressure ( C SL ) of (E)-isobutyl cinnamate were measured at 298.15–533.15 K by an automatic calorimeter and correlated by a quadratic polynomial.
研究领域:
物理化学
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热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Xiaopo Wang,Kai Kang,Hanxiao Lang
In this work, experimental density data are reported for methyl laurate and ethyl laurate from 283.15 to 363.15 K at pressures up to 60 MPa using a vibrating-tube densimeter. Estimated relative uncertainty of density measurement is 0.001 with a confidence level of 0.95. The experimental data were fitted with a modified Tammann-Tait equation. Average relative deviations between experimental data and calculated results from the equation were 0.016% for methyl laurate and 0.014% for ethyl laurate. In addition, the derived thermodynamic properties, such as isobaric thermal expansivity and isothermal compressibility, were calculated from the modified Tammann-Tait equation.
研究领域:
化学工程
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热力学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2024
·
IF 5.6
Rui Cai,Linlin Gao,Yuxiang Zhang,Lu Cui,Yahong Yuan,Zhouli Wang,Tianli Yue
Alicyclobacillus spp. are one of the major harmful microorganisms that can cause fruit juice spoilage. In this study, the inactivation activity and mechanism of phenyllactic acid (PLA) and glycerol monolaurate (GML) against Alicyclobacillus spp. were evaluated, and their effects on fruit juice quality were also investigated. The results displayed that the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of GML were 0.01–0.02 mg/mL and 0.04–0.60 mg/mL, while those of PLA were in the range of 0.25–0.50 mg/mL and 0.5–16.0 mg/mL, respectively. All of these antibacterial agents disrupted the permeability of cell membranes, destroyed the morphology of bacteria, and led to the leakage of cell contents. GML could stimulate bacteria to release a large number of reactive oxygen species, causing some oxidative damage and destroying bacteria. Treatment with L-PLA could reduce the level of adenosine triphosphate (APT) in cells by inactivating ATP synthase. In addition, the MBC of GML and L-PLA in apple juice were 0.02–0.6 and 0.25–16 mg/mL, respectively, which mainly depended on the strain difference. The treatment of L-PLA and GML had no significant adverse effect on the quality of apple juice, except that GML had some effect on color and organic acids, and L-PLA increased the total acid content. Sensory evaluation revealed that these treatments did not affect the organoleptic properties of apple juice. This study provides preliminary theoretical and data support for the application of GML and L-PLA to control Alicyclobacillus spp. contamination in apple juice.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Jing Fan,Qinglong Meng,Fenhong Song
Biodiesel is recognized as a powerful substitute for diesel fuel. The alcohol can be blended with diesel or biodiesel for certain property improvements. In this research, the liquid thermal conductivity of binary mixtures containing ethyl laurate, typically the important biodiesel component + three alcohols (1-propanol, 1-butanol, and 1-pentanol), was measured in the temperature range between 292 and 362 K at atmospheric pressure. It is estimated that the experimental results’ overall standard uncertainty was no more than 2%; the repeatability was less than ±0.5%. From the experimental data of three binary mixtures, three correlations have been fitted and optimized as they are available in calculating the mixtures’ liquid thermal conductivity.
研究领域:
能源科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Taotao Zhan,Junshuai Chen,Xin Li,Qi Zhou,Maogang He,Ying Zhang
The experimental speeds of sound combined with Brillouin frequency shifts of ethyl laurate at temperatures from 294.97 to 572.89 K along six isobaric lines from 0.1 to 10.0 MPa were measured by Rayleigh–Brillouin light-scattering spectroscopy. The expanded relative uncertainty in the reported speeds of sound in ethyl laurate is estimated to be 1.3% (coverage factor k = 2 with a confidence level of 0.95). Within the temperature limits of 303.15–383.15 K and at pressures up to 10.0 MPa, the derived thermoacoustic properties of ethyl laurate including density, specific isobaric heat capacity, isentropic compressibility, isobaric thermal expansivity, isothermal compressibility, the difference in isobaric and isochoric heat capacity, internal pressure, and intermolecular free length were studied. Because of the heavily updated data of density and the speed of sound in the literature, a modified Jacobson’s model for biodiesels was proposed over the temperature range from 293.15 to 343.15 K, which is able to calculate the intermolecular free length of ethyl laurate with higher accuracy compared with Jacobson’s model.
研究领域:
物理化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Hongyu He,Taotao Zhan,Libin Chen,Ao Dong,Weijie Jia,Wenyu Li,Maogang He,Ying Zhang
The speed of sound in binary mixtures of methyl laurate and n-dodecane can directly characterize fuel injection and NOx emissions from diesel engines. Currently, experimental data on the speed of sound of binary mixtures have not yet been reported. In this study, the speeds of sound of the binary system were measured by using Brillouin light scattering. The speeds of sound were measured in the range of 298.15–568.15 K and 0.1–9 MPa. The relative combined expanded uncertainty for the reported speed of sound is estimated to be 1.6% with the level of confidence is 0.95 (k = 2). The experimental data were correlated as a function of temperature and pressure resulting with absolute average percentage deviations of 0.19, 0.16, 0.20, 0.24, and 0.22% for the mole fractions of n-dodecane being 0.100, 0.300, 0.500, 0.700, and 0.900, respectively. Considering the effect of temperature on the binary interaction parameter kij, kij of the PC-SAFT equation of state (EoS) was fitted using experimental data for methyl laurate and n-dodecane. The speeds of sound of binary system were calculated using the PC-SAFT EoS, and the average absolute relative deviation is 2.7%.
研究领域:
热物理学
·
燃料工程
·
发动机技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2017
·
IF 2.726
Hui Ding,Wenjing Ke,Dan Zhao,Lulu Wang,Yujie Gao,Shejiang Liu
In this work, we measured the isobaric vapor-liquid equilibrium (VLE) data for the binary system of methyl caprate (1) + methyl laurate (2) at 2,4 and 6 kPa with a modified Othmer still. The point consistency test of Van Ness test method was applied to check the thermodynamic consistency of all the experimental values, which guaranteed the reliability of our measurements. Afterwards, the experimental data were regressed by two activity coefficient models (Wilson, NRTL). Furthermore, we made the data prediction with the group contribution method (UNIFAC) and the COSMO-SAC model. The results of all the regressions and predictions are satisfying and reasonable, while the results provided by the NRTL model are relatively better than the other three models, with the root mean square deviations of temperature and vapor-phase mole fraction less than 0.33 K and 0.0069, respectively.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）