FOOD CHEMISTRY
·
2020
·
IF 6.306
MengTing Zhu,Ting Shi,ZiYan Guo,HongXia Liao,Yi Chen
The oxidation of cold-pressed and commercial refined camellia oil stored at room temperature for one year was comparatively studied by 1 H and 31 P NMR spectroscopy. The oxidation of extra virgin olive oil (EVOO) under the same conditions was further compared. The 1 H NMR showed that no aldehydes were formed in the studied period. Coupled with the changes of unsaturated acyl groups, the oxidation degrees of the three oils could be obtained follow the order: commercial refined camellia oil > cold-pressed camellia oil > EVOO. The 31 P NMR showed that the evolution of diacylglycerols (DGs) and ratio D in commercial refined camellia oil was fairly different from other two oils. Besides, the kinetics curves of unsaturated acyl groups and ratio D both fit to an exponential equation with high coefficients which indicated that the oxidation of the studied oils progressed in an exponential way with storage time at room temperature.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 120
·99084-99094
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IF 3.84
Xiaowei Lei,Hongyan Wang,Yaorong Feng,Jianxun Zhang,Xuejiao Sun,Suming Lai,Zhilong Wang,Song Kang
A novel 1H-benzo-imidazole phenanthroline derivative (1) was developed as a corrosion inhibitor for mild steel in 1.0 M HCl solution with temperature ranging from 25 °C to 90 °C. Potentiodynamic polarization, electrochemical impedance spectroscopy and weight loss indicates that inhibitor 1 can efficiently protect mild steel from corrosion in acidic medium with better performance under moderately higher concentration and temperature. Based on thermodynamic and kinetic analysis, it is observed that 1 functioned as a mixed-type inhibitor and obeyed Langmuir adsorption isotherm via chemisorption. Further assisted by synergistic effect of iodide ions, inhibition efficiency can be dramatically enhanced up to 99.2%.
研究领域:
腐蚀科学
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材料化学
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电化学
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热力学
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金属防护
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DOI
高影响因子
Materials Today Chemistry
·
2026
·
IF 7.4
Mengnan Yin,Huang Zhang,Di Zhang,Lin Shi,Fangfang Li,Baoshan Xing
During the self-assembly of graphene oxide (GO) into three-dimensional graphene-based materials (3D GMs), close-cell structures are formed. However, the specific effects of these structures on the adsorption of 3D GMs remain unclear. To address this, we synthesized a series of 3D GMs with varying proportion of close-cell structures to systematically investigate their impact on Bisphenol A (BPA) adsorption. Prolonged ultrasonic treatment for GO suspension reduced GO sheet size and increased the abundance of close-cell structures in 3D GMs. Raman spectroscopy, isotope tracing, thermogravimetric analysis, and 1 H NMR measurements revealed that freeze-thawing converts confined water into free water, suggesting the destruction of close-cell structures. The freeze-thawing treatment enhanced the BPA adsorption capacity of graphene hydrogel (GH), and this enhancement was more pronounced with the decreased size of GO nanosheets. This result demonstrated that GH samples with a higher abundance of close-cell structures generated more newly exposed adsorption sites for BPA during freeze-thawing. Furthermore, adsorption experiments in real environmental water (Dianchi Lake) demonstrated that although the BPA adsorption on freeze-thawing graphene hydrogel (FGH-60 m) decreased by 43% compared to in pure water, it still exhibited higher BPA adsorption than that of GH-60 m in lake water. This indicates that the close-cell structures retain significant potential for pollutants adsorption in practical environmental applications.
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高影响因子
JOURNAL OF ANALYTICAL CHEMISTRY
·
2024
·Vol. 79
·期 2
·233-240
·
IF 1
Wai Phyu Thin,Jiang Pingping,Lu Minjia,Cui Zhixuan,Feng Shan,Zhang Pingbo
High-resolution 1 H nuclear magnetic resonance ( 1 H NMR ) was advanced to determine both epoxy value and iodine value ( IV ) of vegetable oils that occur during their epoxidation. For calibration, rather than using a series of diluted stock samples, epoxidized soybean oils with a range of IV and epoxy value synthesized using entrapped peroxophosphotungstate as the catalyst under different reaction conditions were used. During the epoxidation reaction, IV and epoxy value were tracked with respect to time using 1 H NMR and conventional volumetric methods. The integrated peak area of the olefinic hydrogens (5.3–5.5 ppm) was used to calculate the absolute number of double-bonded protons. By comparison of IV obtained by 1 H NMR and the traditional Wijs-cyclohexane methods, the correlation coefficient was R 2 = 0.9997 for the regression equation y = 1.1314 x + 1.0035, where x was the result given by 1 H NMR. The average integrated peak areas related to the hydrogens of the epoxide groups located at chemical shifts of 2.9 ppm (monoepoxide) and 3.1 ppm (diepoxide) were used to determine the epoxy value. The quantification of the number of epoxides was carried out by 1 H NMR and the values obtained were correlated with epoxide content determined by the hydrochloric acid/acetone method. As a consequence, the correlation coefficient was R 2 = 0.9991 for the regression equation y = 0.0052 x + 1.7258, where x was the average integrated peak areas related to the hydrogens of the epoxide groups by 1 H NMR. The novelty of our study lies in the simultaneous correlation between IV and epoxy value obtained from conventional titrations, the integrated peak area related to olefinic protons, and the average integrated peak area located at the hydrogen of epoxide group, calculated using 1 H NMR. This approach is used to monitor and optimize the epoxidation reaction.
研究领域:
分析化学
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高分子科学
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有机化学
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光谱学
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化学反应工程
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2020
·
IF 3.004
Youzhen Tan,Biying Chen,Cui Ren,Mingxin Guo,Juanxia Wang,Kexing Shi,Xia Wu,Yifan Feng
Sandalwood is one of the most valuable woods in the world. However, today's counterfeits are widespread, it is difficult to distinguish authenticity. In this paper, similar genus ( Dalbergia and Pterocarpus ) and confused species ( Gluta sp .) of sandalwood were quickly and efficiently identified. Rapid identification model based on 1 H NMR and decision tree (DT) algorithm was firstly developed for the identification of sandalwood, and the accuracy was improved by introducing the AdaBoost algorithm. The accuracy of the final model was above 95%. And the feature components between different species of sandalwood were further explored using UHPLC-QTOFMS and NMR spectrometry. The results showed that 183 compounds were identified, among which 99 were known components, 84 were unknown components. The 1 H NMR and 13 C NMR signals of 505 samples were assigned, among them, 14 compounds were attributed, characteristic chemical shift intervals with great differences in the model were analysed. Furthermore, the fragmentation pattern of different compounds from sandalwood, in both positive and negative ion ESI modes, was summarized. The results showed a potential and rapid tool based on DT, NMR spectroscopy and UHPLC-QTOFMS, which had performed great potential for rapid identification and feature analysis of sandalwood.
研究领域:
植物学
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分析化学
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药用植物研究
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DOI
PubMed
高影响因子
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES
·
2016
·Vol. 71
·期 8
·869-874
·
IF 0.686
Gao-Feng Wang,Xiao Zhang,Shu-Wen Sun,Hong Sun,Xia Yang,Hui Li,Chen-Zhong Yao,Shu-Gang Sun,Yu-Peng Tang,Li-Xin Meng
Two Mn(II) complexes, {[Mn(BIPMO) 2 Cl 2 ] · 2(H 2 O)} n ( 1 ) and {[Mn(BIPMO) 2 (SCN) 2 ] · 2(CH 3 OH)} n ( 2 ) (BIPMO = bis(4-(1 H -imidazol-1-yl)phenyl)methanone) with V-shaped BIPMO ligands, were synthesized and characterized by IR spectroscopy and elemental analyses along with their single-crystal X-ray diffraction analyses. The Mn(II) ions in 1 and 2 are both six-coordinated to four nitrogen atoms of four BIPMO ligands and two anions (Cl − for 1 , and SCN − for 2 ) to form a distorted octahedral geometry.
研究领域:
配位化学
·
晶体学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2014
·Vol. 38
·期 7
·3078-3083
·
IF 3.159
Dan Kong,Yanyan Liu,Juan Zhang,Hongbian Li,Xiangyu Wang,Guangyu Liu,Baojun Li,Zheng Xu
The research on the heterogeneous catalytic synthesis of tetrazoles has attracted great attention. In this paper, a tungsten atom-containing AlPO-5 microporous molecular sieve (termed as WAlPO-5) was designed and synthesized by the incorporation of tungsten atoms into the AlPO-5 skeleton with triethylamine as a structure template from pseudoboehmite, H3PO4 and tungstophosphoric acid. The incorporation of tungsten atoms into the AlPO-5 skeleton has been demonstrated by systematic characterizations. WAlPO-5 can be used as an efficient heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles by [3+2] cycloaddition from nitriles and sodium azide. As a novel heterogeneous catalyst, WAlPO-5 exhibits a high catalytic activity, a superior cycling stability and an excellent substrate applicability. The significant advantages of WAlPO-5, such as the simple procedure and the mild reaction conditions and as an alternative to those corrosive, hazardous and polluting homogeneous catalysts, warrant its potential application in industrial processes.
研究领域:
化学
·
催化科学
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DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2016
·
IF 3.169
Xialin Chen,Yujie Guo,Yuanjia Hu,Boyang Yu,Jin Qi
Salvianolate Lyophilized Injection (SLI), a traditional Chinese medicinal (TCM) preparation which is used to treat stroke, is composed of multiple salvianolic acids from the aqueous extracts of Salvia miltiorrhiza , and includes mainly protocatechualdehyde, rosmarinic acid, salvianolic acid B, salvianolic acid D, salvianolic acid E, diastereomer of salvianolic acid E, salvianolic acid Y, lithospermic acid and diastereomer of lithospermic acid. It is difficult to quantitatively control the quality of SLI using traditional high performance liquid chromatography due to the highly similar structure of these constituents including three pairs of diastereomers and the lack of commercial resources for most of these constituents as standards. Thus, a highly reproducible, fast, accurate and simple 1 H quantitative nuclear magnetic resonance (qNMR) method without the need for calibration curves and complex computation was established by optimizing the solvent system and acquisition parameters to simultaneously determine the nine salvianolic acids and mannitol in SLI. This method was validated and successfully used to determine 10 batches of SLI and the qNMR data were further analyzed with a vector including angle cosine and the partial least squares method for the quality control of SLI. The results indicated that qNMR can be used as a routine method for the quality control of SLI and may have potential in the quantification of diastereomers in other TCM preparations.
研究领域:
药学
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分析化学
·
传统中医药
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Pengbo Wang,Xingshuang Lv,Bingqian Zhang,Tengbin Wang,Chenbo Wang,Jiaxi Sun,Kun Zhang,Ya’nan Wu,Jian Zhao,Yongqin Zhang
Under the assistance of 13 C NMR and 1 H- 13 C HSQC, we develop a novel 1 H NMR assay for the substitution sites and degrees in hydroxypropyl chitosan (HPCS) by optimizing sample preparation and measurement method. We find that the chemical shift of HOD peak increases linearly with the increase of DCl concentration but declines with the rise of measurement temperature. According to the regression line, the HOD peak could be moved to a desired position of non-interference with other peaks by changing DCl concentration. Other DCl-responsive peaks are found and elucidated. Accordingly, the substitution fraction (NH 2 -substitution and OH-substitution) and the degree of acetylation are well discriminated and determined. The total molar degree of substitution (MS) obtained is basically consistent with those of elemental analysis and the existing NMR methods. This structural analysis is extendable to other amino-containing saccharides. The 1 H NMR method could be used widely in acid-soluble polysaccharides and their derivatives.
研究领域:
生物化学
·
分析化学
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DOI
PubMed
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2023
·
IF 5.4
Yi Huang,Chenyang Zhao,Yue Li,Chen Wang,Tao Shen,Di Cheng,Hui Yang
Zeolitic imidazolate framework-8 (ZIF-8)-based pH-responsive nanocontainers present a new pathway to endowing sol-gel anticorrosion coatings with self-healing ability. The organic nature of the ZIF-8-based nanocontainers, however, makes them less compatible with the inorganic sol-gel coating matrix, thus ineffective in protection against corrosion. In this paper, a novel pH-responsive corrosion inhibitor release system (BTA-ZIF-8@SiO 2 ) based on ZIF-8 for self-healing sol-gel anticorrosion coating was reported. A facile one-step self-assembly procedure was used to create the 1H-benzotriazole (BTA)-encapsulated ZIF-8 core, on which a layer of silica was subsequently coated using a standard sol-gel method. The silica shell can provide better compatibility of the nanocontainers with the sol-gel matrix, thus improving the overall corrosion protection . Characterizations of the BTA-ZIF-8@SiO 2 nanocontainers via X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy , thermogravimetric analysis , Brunauer−Emmett−Teller, scanning electron microscopy/energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy confirmed the successful synthesis of ZIF-8-based nanocontainers with high loading content of BTA and mesoporous SiO 2 shell. Inhibitor release studies revealed the pH-responsive smart release of inbuilt BTA at both acidic and alkaline media. The anticorrosion performance of sol-gel coating incorporating the nanocontainers was investigated by electrochemical impedance spectroscopy , scanning Kelvin probe , and salt spray test , and the results indicated that BTA-ZIF-8@SiO 2 could effectively enhance the corrosion protection properties of the coating and exhibit excellent self-healing performance, in which the |Z| 0.01Hz was >2 orders of magnitude higher and coating resistance and oxide layer resistance were >3 orders of magnitude higher than these of pure sol-gel coating after 28 d of immersion. This could be attributed to the synergistic effect of enhanced passive protection, improved nanocontainer compatibility with the sol-gel matrix, and corrosion inhibitor film formed on metal surface .
研究领域:
材料科学
·
腐蚀与防护
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·
IF 5.8
Meng Hui-Hui,Liu Wen-Ya,Zhao Wen-Long,Zheng Qi,Wang Jun-Song
Trichlorfon, one of the most widely used organophosphate insecticides, is commonly employed in aquaculture and agriculture to combat parasitic infestations. However, its inherent instability leads to rapid decomposition into dichlorvos (DDVP), increasing its toxicity by eightfold. Therefore, the environmental effects of trichlorfon in real-world scenarios involve the combined effects of trichlorfon and its degradation product, DDVP. In this study, we systematically investigated the degradation of trichlorfon in tap water over time using HPLC and LC–MS/MS analysis. Subsequently, an experiment was conducted to assess the acute toxicity of trichlorfon and DDVP on goldfish ( Carassius auratus ), employing a 1 H NMR-based metabolic approach in conjunction with serum biochemistry, histopathological inspection, and correlation network analysis. Exposure to trichlorfon and its degradation product DDVP leads to increased lipid peroxidation, reduced antioxidant activity, and severe hepatotoxicity and nephrotoxicity in goldfish. Based on the observed pathological changes and metabolite alterations, short-term exposure to trichlorfon significantly affected the liver and kidney functions of goldfish, while exerting minimal influence on the brain, potentially due to the presence of the blood–brain barrier. The changes in the metabolic profile indicated that trichlorfon and DDVP influenced several pathways, including oxidative stress, protein synthesis, energy metabolism, and nucleic acid metabolism. This study demonstrated the applicability and potential of 1 H NMR-based metabonomics in pesticide environmental risk assessment, providing a feasible method for the comprehensive study of pesticide toxicity in water environments. Graphical abstract
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DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2017
·
IF 5.099
Sisheng Wu,Cuiyuan Jin,Yueyi Wang,Zhengwei Fu,Yuanxiang Jin
Propamocarb (PM) is a widely used fungicide with property of affecting fatty acid and phospholipid biosynthesis in funguses. In this study, we explored its effects on mice gut microbiota and metabolism by exposing mice to 3, 30, and 300 mg/L PM through drinking water for a duration of 28 days. We observed that the transcription of hepatic genes related to regulate lipid metabolism were perturbed by PM exposure. The microbiota in the cecal contents and feces changed during or after PM exposure at phylum or genus levels. 16S rRNA gene sequencing for the cecal content revealed shifted in overall microbial structure after PM exposure, and operational taxonomic unit (OTU) analysis indicated that 32.2% of OTUs changed by 300 mg/mL PM exposure for 28 days. In addition, based on 1 H NMR analysis,a total of 20 fecal metabolites mainly including succinate, short chain fatty acids, bile acids and trimethylamine were found to be significantly influenced by exposure to 300 mg/L PM.,. These metabolites were tightly correlated to host metabolism. Our findings indicated that high doses of PM exposure could disturb mice metabolism through, or partly through, altering the gut microbiota and microbial metabolites.
研究领域:
毒理学
·
微生物学
·
代谢组学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）