TETRAHEDRON
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2023
·
IF 2.1
Yuangui Ye,Quan Zhu,Mingquan Yuan,Rong Huang,Yunhai Tao
The publisher regrets that this article has been temporarily removed. A replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal .
研究领域:
昆虫学
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有机化学
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农业科学
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DOI
高影响因子
Acta Crystallographica Section C-Structural Chemistry
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2018
·Vol. 74
·期 9
·1058-1067
·
IF 8.678
Tan X.-J.,Wang D.,Lei X.-G.,Chen J.-P.
A global glide disorder has been discovered during an X-ray investigation of the crystal structure of (Z)-2-[(E)-(4-methoxybenzylidene)hydrazinylidene]-1,2-diphenylethanone (MHDE, C22H18N2O2) at room temperature. In another crystal, however, such disorder disappears (still at room temperature). Even though the disorder may be partly due to the poor quality of the harvested crystal, the structure can shed light on the nature of disorder. With the help of quantum chemical calculations, it is found that the global disorder seems to be connected with the need for stabilization of the somewhat rigid but mobile and unstable molecular structure. The most relevant feature driving the packing of the disordered structure concerns the slight perturbations (such as glide) of two or more disorder components (fractional occupancies) distributed throughout the crystal.
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DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
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2026
·
IF 5.3
Qingqing Zou,Dan Zhou,Shan Mou,Shuixin Ding,Yingjuan Wang,Chunyan Su,Qianchun Zhang
Vanillin is widely used in food and industrial applications, but excessive intake of vanillin can pose health risks. Therefore, the development of novel detection strategies with high sensitivity and selectivity is essential for the accurate identification of vanillin. Ethyl ( Z )-2-cyano-4-oxo-3,4-diphenylbut-2-enoate (ECOD), a novel fluorescent probe, was synthesized by an elimination reaction using ethyl cyanoacetate, benzil, and aqueous ammonia as raw materials. The probe exhibited maximum fluorescence excitation and emission wavelengths at 300 and 340 nm, respectively, with a quantum yield of 22.6%. ECOD was found to have high selectivity and sensitivity for the detection of vanillin. This was attributed to ECOD binding to vanillin, which induced conformational changes and triggered intermolecular charge transfer (ICT), ultimately resulting in fluorescence quenching. Therefore, a fluorescence-based method was established for the quantification of vanillin in biscuits, candy, and milk sauce. The linear detection range was 1.0–100 µM and the detection limit was 0.33 µM. The recoveries ranged from 93.2% to 113%, with an RSD ranging from 2.8% to 10%. These results indicated that ECOD had significant application potential in food analysis, suggesting that the fluorescence method based on ECOD could provide a novel approach for rapid vanillin determination in complex food matrices.
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DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2013
·Vol. 160
·期 3
·H173
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IF 2.588
Bin Hu,Xiaojing Lv,Jingwei Sun,Mi Ouyang,Zhiyan Fu,Cheng Zhang
In this study, a novel material, Z-2, 3-bis(4-(thiophen-3-yl)-phenyl) –acrylonitrile (Z-TPA), was synthesized and characterized. Optical and electrochromic properties of its homopolymer and copolymer with 3, 4-Ethylenedioxythiophene (EDOT) were investigated in details. UV–vis absorption and fluorescence spectra showed that this material possessed the properties of aggregation-induced emission (AIE) due to the introduction of acrylonitrile, which could show sky-blue emitting at the aggregation state and almost no emitting at the solution state. Both its polymer and copolymer displayed better redox activity. Spectroelectrochemical analysis displayed that the copolymer film exhibited multicolor showing, with a claret red in the fully reduced form and a blue-green color in the fully oxidized. Spectrochronoamperometry data revealed that the copolymer films had fast switching time and high chromatic contrast as compared to the homopolymer P(Z-TPA). What's more, the copolymer film was used to construct a dual type polymer electrochromic device (ECDs) with PEDOT. The performance of ECDs were also investigated.
研究领域:
材料科学
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光学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Jia Huang,Yuping Liu,Wenxi Yang,Yingqiao Liu,Yu Zhang,Mingquan Huang,Baoguo Sun
Beijing douzhi (BD) is a traditional snack in Beijing, China, and it has been listed as a part of Beijing’s intangible cultural heritage. The potent odorants that contribute to the characteristic aroma of BD were investigated by analyzing the isolates from solvent-assisted flavor evaporation (SAFE) and simultaneous distillation–extraction. Using aroma extract dilution analysis based on gas chromatography–mass spectrometry and gas chromatography-olfactometry, 31 aroma-active compounds with flavor dilution (FD) factors ranging from 1 to 2187 were identified by comparison of their odor characteristics, MS data, and retention indices with those of reference compounds. To further determine their contribution to the aroma of BD, the odorants isolated using SAFE with FD factors ≥9 were quantified, and their odor activity values (OAVs; ratio of concentration to the respective odor threshold in water) were calculated. Eleven compounds were found to have OAVs ≥ 1, which indicated they were the potent odorants that contributed substantially to the characteristic aroma of BD. Among the 11 odorants, (E,Z)-2,6-nonadienal, eugenol, methional, p-cresol, 1-octen-3-one, and 3-methylbutanoic acid were not previously identified in BD.
研究领域:
食品科学
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分析化学
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香料化学
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产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Dan Li,Zheqi Zhang,Kaihua Zhang,Shouwei Wang,Xiaoman Li,Mingwu Zang
Fatty acids and volatile substances in hybrid pork (Duroc × Landrace × Yorkshire; DLY) and four indigenous pork (Guangdong small-ear spotted; hill black; Beijing black, BB; and Qingyu) in raw, cooked, and reheated states were explored. The objectives were to determine odor differences between DLY and indigenous pork and the difference in changes after heating and reheating and to clarify the reasons for these changes. Results revealed that C 18:1 and C 20:4 fatty acids are the key to distinguishing DLY pork from indigenous pork. After cooking, the greatest decrease was observed in the proportion of polyunsaturated fatty acids in pork, and after reheating, monounsaturated fatty acids were detected, except in the BB pork. The substances that accounted for the difference between DLY and indigenous pork were 2,3-octadione, hexanal, 1-octen-3-ol, 2-nonanone (after heating), and (Z)-2-nonenal (after reheating). Reheating reduced the content of nonanal, 2,3-octandione, hexanal, and ( E , E )-2,4-decadienal, resulting in the deterioration of the aroma. In the DLY pork, the dramatic increase in the ( Z )-2-nonenal content may be the key factor. Principal component analysis identified that the difference in aroma between DLY and indigenous pork increased after reheating, but hierarchical cluster analysis showed that regardless of treatment, flavor difference was smaller between DLY and indigenous pork than among indigenous pigs. The analysis results show that differences in fatty acid content and oxidation path in unsaturated fatty acids were the reasons for the difference in aroma and the deterioration of flavor after reheating.
研究领域:
食品科学
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农业化学
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动物科学
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产品关联
DOI
高影响因子
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