JOURNAL OF MOLECULAR STRUCTURE
·
2021
·
IF 3.196
Jiancheng Zhao,Rui Liu,Zhenzhou Zhang,Qianqian Xing,Honghong Chang,Xianglin Hou,Yingxiong Wang
The tautomer structure of monosaccharides plays an important role in its conversion and utilization, which is mainly manifested in the selectivity of the product and the reaction mechanism. The tautomer distributions of N -acetyl- D -glucosamine (GlcNAc), a natural nitrogen-containing monosaccharide were investigated by quantitative 1 H NMR ( 1 H qNMR) and 13 C NMR ( 13 C qNMR) at 298 K under the condition commonly utilized for biorefinery. Catalysts used for biorefinery, i.e. BaCl 2 , KCl, ZnCl 2 , MgCl 2 , B(OH) 3 , SnCl 4 ·5H 2 O and amino acid ionic liquid were introduced into D 2 O or DMSO‑ d 6 to explore the tautomer distributions of GlcNAc. The introduction of ZnCl 2 and SnCl 4 ·5H 2 O promoted the conversion of α-pyranose to β-pyranose. The introduction of amino acid ionic liquid has little effect on the percentage of tautomers in D 2 O. However, when the amino acid ionic liquid, such as [Thr]Cl, was introduced into DMSO‑ d 6 , the proportion of β-pyranose increased to 29.06%, compared with no catalyst introduced. Besides, we also studied the tautomer distributions of GlcNAc in commonly utilized reaction solvents for biorefinery, such as N,N -dimethylformamide, N , N -dimethylacetamide, N -methyl-2-pyrrolidinone, ethylene and glycerol. In these solvents, the proportion of β-pyranose in N,N -dimethylformamide and glycerol was reduced to 25.84% and 38.38%, respectively. This study provides the basic experimental data of tautomer distributions of GlcNAc, and guided the conversion and utilization of GlcNAc in the future.
研究领域:
生物化学
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分析化学
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Jiahao Liu,Xiaojie Jin,Xi Lu,Xinyu Huang,Hongyan Chen,Long Qiu,Xiaowei Huang,Yongxiu Li,Jing Li
The application of rare earth micro-nano materials requires first formulating them into slurries with high dispersion stability, including polishing powders, catalysts, phosphors, ceramics, and other materials. To achieve this, it is essential not only to prepare monodisperse micro-nano particles but also incorporate appropriate dispersants to prevent particle aggregation. For this purpose, the study designed and synthesized a core-shell structured Gd 3 + -doped CeO 2 -coated SiO 2 composite abrasive: SiO 2 /CeO 2 :Gd. Low-field nuclear magnetic resonance technique was employed to investigate the sedimentation behavior of polishing slurries and explore the mechanism by which different dispersants enhance slurry dispersion stability, achieving real-time nuclear magnetic resonance imaging tracking of the sedimentation process. Results show that: The strong paramagnetic properties of Gd 3+ significantly enhance the relaxation efficiency of water molecules within the particle surface region, thereby serving as a sensitive probe for characterizing the liquid environment at the particle surface. Based on the T 2 distributions, settling can be divided into three stages: homogenization, sedimentation, and agglomeration. In polishing slurries, water molecules primarily exist in three forms: bulk water (P1), hydration layer water (P4) and surface-bound water (P5), attributing to different peaks of T 2 relaxation times. However, only one T 2 peak (P2) was observed for the homogenization slurry due to the rapid exchange among the three kind of water molecules. With the sedimentation proceeding, P2 transforms into two peaks of P1 and P3. The rate of change in the peak areas of P1 and P2 can reflect the sedimentation rate of the slurry. In the agglomeration stage, the overlapping of hydration layers forms interstitial water, leading to an increase in its T 2 relaxation time. Therefore, the P3 can further split into two peaks of P4 and P5, corresponding to interstitial water and surface-bound water in the sediment layer.
研究领域:
材料科学
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核磁共振（NMR）
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化学机械抛光（CMP）
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胶体与界面科学
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纳米技术
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DOI
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Shinuo Kang,Fushan Geng,Xiaobing Lou,Guozhong Lu,Yuxin Liao,Ming Shen,Bingwen Hu
The extreme fast charging (XFC) capability of graphite anodes is becoming increasingly important with the development of electric vehicles due to the usage and safety requirement. In this work, the XFC performance of the graphite anodes is improved by simply adding fluoroethylene carbonate (FEC) into the electrolyte. This robust system is studied by in situ nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) experiments to unravel the kinetic mechanism. The Li local environments in the graphite are detected by in situ NMR, which reveals the phase transitions during XFC without and with the FEC additive and the corresponding Li-ion mobility. The graphite conductivity variation is estimated by in situ EPR, and the plated Li can be clearly observed in the later period of XFC. The kinetics of graphite lithiation is deduced to be surface-controlled during the dilute stages and bulk-controlled during the dense stages. The solid electrolyte interphase (SEI) formed with FEC is more homogeneous and richer in LiF, which delivers a faster Li+ transport ability and results in the improvement of the surface kinetics. The major advantage of FEC additive is in the optimization of the Li plating behavior. Without FEC, the Li deposits grow locally, while the FEC additive consumes more currents to form the SEI and facilitate the uniform deposition of metallic Li on graphite during XFC. These results display the versatility of in situ NMR and EPR technologies in the research of XFC kinetics.
研究领域:
电化学
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电池技术
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材料科学
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原位表征
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储能
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2026
·
IF 6.7
Sen Guo,Jing Gao,Yu Zhang,Jinchang Xiang,Haoyu Li,Wei Zhou,Tianchen Ma,Lu Bai,Naisheng Bai,Wei Cao
In-depth chemical characterization provides key fingerprints for honey authentication. An integrated approach combining UHPLC-Q-TOF/MS-based molecular networking (MN) with HSQC NMR-based small molecule accurate recognition technology (SMART) was applied to characterize the chemical profile of Apis cerana honey from the Qinling Mountains. Twenty-eight metabolites were identified, with alkaloids and lipids being the most abundant. Targeted isolation of predominant fractions yielded four alkaloids (lumichrome, chestnutamide, deoxyvascinone, and 2-quinolone), one ionone derivative (plasiaticine I), and one ester (cetyl triacontanoate), all first reported in A. cerana honey as potential markers. 1H NMR-based metabolomics coupled with OPLS-DA showed 13 unifloral honeys clustered by botanical origin. With this model, characteristic NMR signals of A. cerana honey (δH 2.28 [t], 3.45 [s], 4.05 [t] ppm) were identified, among which the two triplets match the oxygenated methylene of the isolated compounds. These findings clarify the chemical basis of A. cerana honey and provide an integrated approach for authentication.
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DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 9
·期 7
·3985-3994
·
IF 11.301
Ruidi Wang,Bei-Bei Xu,Jiachen Wang,Xue Lu Wang,Ye-Feng Yao
The relationship between the structural characteristics and photocatalytic reaction mechanisms of graphitic carbon nitride (g-C3N4) still remains unclarified at the molecular level, which severely hinders the further development of this field. The present study addresses this issue by employing an innovative strategy to investigate the relationship between the H-containing structures of g-C3N4 and its water splitting properties. The exchangeable and unexchangeable protons of the H-containing groups of g-C3N4 were differentiated by selective deuteration, providing a way to distinguish the hydrophilic and relatively non-hydrophilic H-containing groups of g-C3N4. A combination of advanced solid-state NMR approaches reveals that amino group defects (CN2(NHx)) on the C–N skeleton of the photocatalyst likely serve as hydrophilic active sites for facilitating the photocatalytic hydrogen evolution reaction. Accordingly, the newly synthesized g-C3N4 sample having a high concentration of CN2(NHx) by design demonstrates an enhanced H2 yield by a factor of 17 compared to that of pure g-C3N4.
研究领域:
材料化学
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光催化
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固体核磁共振
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表面科学
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能源材料
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Yingqing Zhao,Rui Liu,Christian Marcus Pedersen,Zhenzhou Zhang,Zhaohui Guo,Honghong Chang,Yingxiong Wang,Yan Qiao
Lactic acid (2-hydroxypropionic acid, LA) can be produced from abundant and renewable biomass resources via chemocatalytic processes, which exhibited high potential for meeting its tremendous demand in a wide range of applications. The basic Ba(OH) 2 could efficiently catalyze the conversion of d -glucose into LA. In the present study, by utilizing various NMR techniques including, chemical shift titration, 2D diffusion ordered spectroscopy (DOSY) analysis, heteronuclear singular quantum correlation ( 1 H– 13 C HSQC), the binding sites and catalytic interaction between d -glucose and catalyst were clarified. The experimental results by NMR and electrospray ionization mass spectrometry (ESI–MS) were used to explore the reaction mechanism. Experimental results disclosed that the catalyst, Ba(OH) 2 , may exist in the form of [Ba(OH)(H 2 O) 2 ] + under the reaction condition. The OH – of [Ba(OH)(H 2 O) 2 ] + is attached to the C5-O of d -glucose, and Ba 2+ is connected to the C1-O of d -glucose. Herein, we suppose that Ba(OH) 2 and d -glucose interact and form a complex, d -glucopyranose-[Ba(OH)(D 2 O) 2 ] + . Furthermore, when the reaction was performed in D 2 O, we were surprised to find that LA underwent varying degrees of deuteration. The reaction mechanism, binding sites and deuteration of the product have shed light on the efficient conversion of biomass to LA.
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DOI
高影响因子
Scientific Reports
·
2016
·
IF 5.228
Shufang Wang,Haiqiang Wang,Yining Liu,Yi Wang,Xiaohui Fan,Yiyu Cheng
The traditional activity-guided approach has the shortcoming of low accuracy and efficiency in discovering active compounds from TCM. In this work, an approach was developed by integrating activity index (AI), liquid chromatography - mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR) to rapidly predict and identify the potential active constituents from TCM. This approach was used to discover and identify the anti-inflammatory constituents from a TCM formula, Gui-Zhi-Jia-Shao-Yao-Tang (GZJSYT). The AI results indicated that, among the 903 constituents detected in GZJSYT by LC-MS, 61 constituents with higher AI values were very likely to have anti-inflammatory activities. And eight potential active constituents of them were isolated and validated to have significant inhibitory effects against NO production on LPS-induced RAW 264.7 cell model. Among them, glycyrrhisoflavone (836), glisoflavanone (893) and isoangustone A (902) were reported to have anti-inflammatory effects for the first time. The proposed approach could be generally applicable for rapid and high efficient discovery of anti-inflammatory constituents from other TCM formulae or natural products.
研究领域:
药理学
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分析化学
·
中医药
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Yongqiang Li,Peixiang Ma,Quan Tao,Hans-Joachim Krause,Siwei Yang,Guqiao Ding,Hui Dong,Xiaoming Xie
The rapid and sensitive diagnosis of the highly contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the crucial issues at the outbreak of the ongoing global pandemic that has no valid cure. Here, we propose a SARS-CoV-2 antibody conjugated magnetic graphene quantum dots (GQDs)-based magnetic relaxation switch (MRSw) that specifically recognizes the SARS-CoV-2. The probe of MRSw can be directly mixed with the test sample in a fully sealed vial without sample pretreatment, which largely reduces the testers’ risk of infection during the operation. The closed-tube one-step strategy to detect SARS-CoV-2 is developed with home-made ultra-low field nuclear magnetic resonance (ULF NMR) relaxometry working at 118 μT. The magnetic GQDs-based probe shows ultra-high sensitivity in the detection of SARS-CoV-2 due to its high magnetic relaxivity, and the limit of detection is optimized to 248 Particles mL ‒1 . Meanwhile, the detection time in ULF NMR system is only 2 min, which can significantly improve the efficiency of detection. In short, the magnetic GQDs-based MRSw coupled with ULF NMR can realize a rapid, safe, and sensitive detection of SARS-CoV-2.
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DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2021
·
IF 6.165
Hui Ma,Dan Luo,Qi Zhao,Rui Liu,Zhenzhou Zhang,Xianglin Hou,Xiaohuan Sun,Yingxiong Wang
Diffusion-ordered spectroscopy (DOSY) is a powerful and efficient technique for the analysis of complex mixtures, relying on their differential in self-diffusion coefficient. However, DOSY is often struggled to separate signals pertaining to isomeric species, especially positional isomers. Here, for the first time, we describe the novel design of 18-crown ether-6 (18C6) and 18C6/K + complex as matrixes to discriminate and identify positional isomeric mixtures of phenylenediamine, nitroaniline, phthalic acid, dimethoxybenzoic acid, aminophthalic acid and even amino acids using 1 H DOSY spectrum. The superior performance of 18C6 and 18C6/K + complex as matrix depends on that they can interact with different components with varying binding energy as demonstrated by MMMF calculations and the DFT calculation. The methodology presented here is simple yet efficient. Moreover, the crown ether and crown ether/K + complex provide the dual mode discrimination for both amino and carboxylic substituted positional isomers.
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高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2017
·Vol. 46
·期 12
·2281-2292
·
IF 1.342
Liu Bijun,Tian Yin,Yu Qianhong,Li Qiang,Mu Wanjun,Tan Zhaoyi,Wu Fengchang,Wang Dongqi,Li Xingliang
O-Phospho- l -serine is one of the naturally occurring phosphorylated amino acids, having important pharmacological activity and bioactivity. The protonation constants of O-phospho- l -serine were determined by means of potentiometric titrations at 25 °C and ionic strength of 0.5 mol·L −1 (NaCl). The heat effects of the protonation reaction of the O-phospho- l -serine were measured by direct calorimetry. NMR spectroscopy has demonstrated that the first protonation site occurs at the nitrogen atom in the amino group, followed by one of the oxygen atoms in the phosphono group, and finally the carboxyl oxygen atom. This trend is in good agreement with the enthalpy of protonation and quantum chemical calculations. These data will help to predict the speciation of O-phospho- l -serine in physiological systems.
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高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2022
·Vol. 24
·期 34
·20073-20081
·
IF 3.945
Ruifen Shi,Fengyi Zhou,Yu Chen,Zhenghui Liu,Shuzi Liu,Tiancheng Mu
Deep eutectic solvents (DESs) are well-known as novel solvents due to their unique properties, which are indispensable for the development of green chemistry in the future. CoCl2·6H2O and NiCl2·6H2O-based DESs, which could be called magnetic DESs (MDESs) for short in view of their responsive behavior to an external magnetic field, have been widely used in many industrial applications, such as biomass treatment, electrolytes, and material preparation. For better application and full-scale development of these MDESs in various fields, eleven MDESs were prepared in this work by using CoCl2·6H2O and NiCl2·6H2O as hydrogen bond acceptors (HBAs) with alcohols, carboxylic acids and amides as hydrogen bond donors (HBDs), respectively. The intermolecular interactions between the components of MDESs were characterized via FTIR, 1H NMR and DSC analysis. In addition, physicochemical properties including density, viscosity, conductivity, ionicity, pH values, surface tension, thermostability and solvatochromic parameters were investigated. All MDESs exhibit acid characteristics and have good conductivity comparable with ionic liquids (ILs) and other DESs used for electrolytes. The results show that stronger H-bonding networks in Ni-based MDESs make them have higher density, viscosity, polarity and surface tension values than Co-based MDESs. Moreover, all prepared MDESs possess a good conductivity behavior which could be comparable to that of common organic solvents and ILs. According to this work, we could better comprehend the behavior of Co/Ni-based MDESs and choose the appropriate one for particular applications.
研究领域:
化学
·
材料科学
·
绿色化学
·
工业应用
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DOI
高影响因子
Journal of Magnetic Resonance Open
·
2025
·
IF 2
Yue Dou,Qing Wang,Hengxing Ji,Haiming Liu
The spatial dynamics of cations have a significant impact on the photodynamic behavior of excited states in high-performance hybrid organic-inorganic perovskites. Multinuclear ( 1 H, 2 H, and 14 N) solid-state NMR (SSNMR) spectroscopy has traditionally been utilized to study the motion of methylammonium (MA) cations in methylammonium lead (II) halides MAPbX 3 (X = I, Br, Cl). NMR methods based on spin-lattice relaxation or quadrupolar line shape analysis over a limited temperature range demonstrate rapid MA reorientation, but the cation dynamics in a wider temperature range covering phase transition of all major crystallographic phases is lacking. Due to its low sensitivity, 13 C NMR is rarely used to assess MA dynamics in these perovskites. Herein, we adopte variable-temperature (VT) 13 C MAS NMR at very high resolution and dipolar-coupled transverse relaxation analysis as a new tool for dynamical characterization without isotopic enrichment, and systematically investigated MA dynamics in MAPbX 3 across phase transitions. This new approach enables retrieval of activation energy of MA reorientation and assessment of motion regimes. We propose a generalized “Camel model” that describes the common trend of cation dynamics for MAPbX 3 , suggesting possible complicated reorientation modes. Furthermore, we discover the evolution of multiple MA sites in orthorhombic MAPbCl 3 , consistent with X-ray crystallography, demonstrating its unique advantage in resolving and characterizing multi-cation dynamics. The VT 13 C SSNMR effectively probes organic ion motions and phase transitions in hybrid perovskites, helpful for further elucidating the structure-property relationship in photovoltaic conversion mechanisms.
研究领域:
材料科学
·
物理化学
·
光电子学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）