SURFACE AND INTERFACE ANALYSIS
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2021
·Vol. 53
·期 12
·1027-1034
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IF 1.607
Qi Chen,Renhui Zhang,Zhongyi He,Liping Xiong
N-containing heterocyclic compound (NCHC) was a common used green lubricant addictive due to their extreme pressure, antiwear and friction–reduction performance, and high thermal stability, and ethylene glycol (EG) as lubricant exhibited superior tribological performance, combining of NCHCs, which was a suitable candidate for further improving the tribosystems' tribological properties. Thus, in this work, the synergistic effect between EG and 2,4,6-Tris(2-pyridinyl)-s-triazine (TPT) on the tribological performance was explored coupling of the applied loads and rotational speed. The tribological tests showed that TPT played an important role in improving the tribological properties as sliding in TPT@EG; the formation of the tribofilms induced by tribochemical reaction was in charge of enhancing the tribosystem's lubrication performance sliding in TPT@EG.
研究领域:
材料科学
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化学工程
·
机械工程
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产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 23
·7876
·
IF 4.6
Zhang Hu,Hongrui Dong,Zhenyu Si,Yurong Zhao,Yuanwei Liang
Infectious diseases pose a major challenge to human health, and there is an urgent need to develop new antimicrobial agents with excellent antibacterial activity. A series of novel triazolo[4,3-a]pyrazine derivatives were synthesized and their structures were characterized using various techniques, such as melting point,1H and13C nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis. All the synthesized compounds were evaluated for in vitro antibacterial activity using the microbroth dilution method. Among all the tested compounds, some showed moderate to good antibacterial activities against both Gram-positiveStaphylococcus aureusand Gram-negativeEscherichia colistrains. In particular, compound2eexhibited superior antibacterial activities (MICs: 32 μg/mL againstStaphylococcus aureusand 16 μg/mL againstEscherichia coli), which was comparable to the first-line antibacterial agent ampicillin. In addition, the structure–activity relationship of the triazolo[4,3-a]pyrazine derivatives was preliminarily investigated.Keywords:nitrogen-containing heterocycles;triazole compounds;triazolo[4,3-a]pyrazine derivatives;antibacterial activity
研究领域:
药物化学
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微生物学
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有机合成
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DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Qiqiao Liu,Wei Chen,Ying Wang,Zihan Ye,Sheng Liu,Jiang Yu,Guangyi Liu
The molybdenite is a typical layered sulfide mineral with extremely high natural hydrophobicity and therefore it is extracted by flotation technology. However, molybdenite is usually depressed by the flotation regulator lime and needs activization. In this study, we introduced 10 kinds of N-heterocycles to systematically study the structure–activity relationship of the N-heterocyclic flotation activators for the lime inhibited molybdenite, mainly through flotation tests, surface detection and DFT calculation. The flotation results showed that the lime almost irreversibly depressed the molybdenite flotation when using kerosene as collector alone, and adding these N-heterocyclic reagents effectively helped molybdenite regain its high flotability. When lime was used as 120 mg/L and kerosene at 30 mg/L, the activator effect could be ranked as: 3MI ≈ 2Phl ≈ 5 MB ≈ 5MI ≈ TTA > IND ≈ BTA ≈ Bzlm ≈ 5PhTH > 2MZ, which was decided by the recovery increment. The surface detection indicated that the depression mechanism of the lime was mainly through the adsorption of the CaOH + , Ca 2+ , Ca(OH) 2 on the basal plane of molybdenite crystal, thus the chelating affinity of the N-heterocyclic reagents towards the lime components decided its activation ability. The DFT calculation suggested that the N-heterocycles was also able to interact with the Mo sites exposed by surface oxidation on the basal plane, thus the reactivity towards the Mo as well as the steric configuration also determined the activator effect. Therefore, the chelating ability of the activator towards the lime components/exposed Mo sites and the steric configuration of the rest alkyl group both contribute to the structure–activity relationship.
研究领域:
矿物加工
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表面化学
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浮选技术
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计算化学
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DOI
高影响因子
FOOD CHEMISTRY
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2022
·
IF 9.231
Yongkang Ye,Shuangshuang Ye,Zhangxiang Wanyan,Hao Ping,Zixun Xu,Shudong He,Xiaodong Cao,Xiangyang Chen,Wanwan Hu,Zhaojun Wei
This work investigated the effect of oxidized beef tallow on the volatile compositions and sensory properties of soybean meal-based Maillard reaction products (MRPs). Various tallow oxidation methods included thermal treatment (TT), enzymatic hydrolysis (ET) and enzymatic hydrolysis combined with mild thermal (ETT) treatment. Results showed that all these oxidized tallow contained more types of volatile compounds than those of untreated tallow. Moreover, the composition of almost all types of volatile substances was greatly increased with the addition of the oxidized beef tallow into the hydrolyzed soybean meal-based Maillard reaction system. More importantly, the composition of oxygen-containing heterocycles (63.89 μg/mL), sulfur-containing compounds (76.64 μg/mL), and nitrogen-containing heterocycles (19.81 μg/mL) that contribute positively to sensory properties in ETT-MRPs was found to be the highest among all the MRPs. Correlation assessment revealed that ETT was closely related to the most typical volatile products and sensory attributes, indicating this approach can effectively enhance the sensory and flavor of hydrolyzed soybean meal derived MRPs.
研究领域:
食品科学
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化学
·
感官评价
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Yu Liu,Linlin Qin,Yiming Qin,Tong Yang,Haoran Lu,Yulong Liu,Qiqi Zhang,Wenyan Liang
Nitrogen-containing heterocyclic compounds (NHCs) are hazardous, toxic, and persistent pollutants, thereby requiring urgent solutions. Herein, ZIF-67 was compounded with powder-activated carbon (PAC) to prepare Co/NC/PAC (NC i.e. nitrogen-doped carbon) particle electrodes for the electrocatalytic treatment of pyridine and diazines . Co/NC/PAC reflected the confinement of Co 3 O 4 /CoN/Co 0 into the N-doped graphitic-carbon layer to generate both pyrrolic-N and graphitic-N active sites. Under the optimal conditions (0.3 A, 12 mL min −1 , and initial pH 7.00), the degradation of four NHCs realized 90.2–93.7% efficiencies. The number and position of N atoms in NHCs directly affected the degradation efficiency. The following increasing order of facilitated degradation was recorded: pyridazine < pyrimidine < pyrazine < pyridine. The as-obtained Co/NC/PAC possessed the direct redox effect on NHCs, achieving fast electrocatalytic rate. Species like ·OH and H* were detected in Co/NC/PAC system with contributions to NHCs degradation estimated to 24% and 34%, respectively. Density functional theory (DFT) calculations revealed H* susceptible to attacking the N position, while the meta-position of C was subject to hydroxyl radical (·OH) addition. Overall, degradation of NHCs was achieved by hydro-reduction, oxidation , ring opening cleavage, hydroxylation, and mineralization. Ring-cleavage and mineralization of NHCs provided a novel electrochemical strategy to refractory wastewater treatment .
研究领域:
环境科学
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电化学
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材料科学
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废水处理
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Chunying Song,Gaowa Jin,Dongping Yu,Zhimou Guo,Xinmiao Liang
A novel silica stationary phase was designed and prepared through thiol-epoxy click chemistry for supercritical fluid chromatography (SFC). The developed stationary phase was characterized by elemental analysis, Fourier transform infrared spectrometry and solid-state 13 C/CP MAS NMR spectroscopy. In order to evaluate the chromatographic performance and retention mechanisms of the prepared column, a variety of alkaloids were used, including indoles, isoquinolines, pyrrolidines, piperidines, quinolizidines and organic amines. The stationary phase showed more symmetrical peak shapes and better performance for these compounds compared to the conventional SFC stationary phases. The investigations on the effects of pressure and temperature on retention provided information that the selectivity of the compounds can be improved by changing the density of the supercritical fluids. Moreover, it shows improved separation efficiency of three natural products with alkaloids as the main components at high sample loading. In conclusion, the developed stationary phase could offer flexible selectivity toward alkaloids and complex samples.
研究领域:
分析化学
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色谱技术
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超临界流体技术
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有机化学
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产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2022
·
IF 7.425
Zuoyong Zhang,Shudong He,Luji Zhang,Xinjiang Li,Risheng Jin,Qian Liu,Shuguan Chen,Junhui Wang,Hanju Sun
Vegetable oils with different unsaturated degrees (corn > peanut > olive > palm > coconut) and corresponding enzymatic hydrolysis-thermal oxidation (ENTH) oils were added into D-xylose and L-cysteine Maillard reaction (MR) system, respectively, for potential meaty aroma production. Results indicated that coconut oil and palm oil had lower peroxide, p -anisidine, total antioxidant values, and malondialdehyde content after ENTH and MR. Corn, peanut, and olive oils after ENTH could significantly promote MR because they caused the lower pH, higher reactants depletion, and higher browning degree in the water phase separated from the oil-Maillard reaction system. Additionally, the volatiles were mainly formed from oil phase. Corn, peanut, and olive oils were beneficial to volatiles formation in the oil-MR system due to fatty acid oxidation, especially oleic acid and linoleic acid. Meanwhile, compared to raw oils, adding ENTH oils to the MR system could reduce the content of oxygen, nitrogen, and sulfur-containing heterocycles.
研究领域:
食品科学
·
化学工程
·
农业化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）