CERAMICS INTERNATIONAL
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2020
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IF 3.83
Shengdong Sun,Hui Liu,Longlong Fan,Yang Ren,Xianran Xing,Jun Chen
Grain size effect plays a vital role in piezoelectric performance from both scientific and technological view. However, the underlying structural mechanism related to grain size is still unclear. In the present study, the structural mechanism of grain size effect on piezoelectric performance has been revealed in the prototype Pb(Zr,Ti)O 3 system by using in-situ synchrotron X-ray diffraction. The miniaturization of grain size tends to favor the appearance of higher symmetric tetragonal phase, while a single monoclinic phase is determined in the coarse-grained ceramics. The direct structural evidence reveals that both tetragonal and monoclinic phases in the fine-grained ceramics are less sensitive to the electric field, corresponding to the inferior piezoelectric performance, while the single monoclinic phase in the coarse-grained ceramics is more active to be driven by the electric field, generating good piezoelectric behavior. Both domain switching ability and lattice strain are suppressed with decreasing grain size, which directly leads to the deterioration in piezoelectric performance. The current results will benefit the structural understanding of the size effect of piezoelectric and other related systems.
研究领域:
材料科学
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物理学
✓ 已验证
DOI
高影响因子
Journal of the American Chemical Society
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2022
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IF 16.383
Guohua Xu,Jiajing Zhao,Hao Yu,Chen Wang,Yangyu Huang,Qiang Zhao,Xin Zhou,Conggang Li,Maili Liu
A 36-mer guanine (G)-rich DNA aptamer (OBA36) is able to distinguish one atomic difference between ochratoxin analogues A (OTA) and B (OTB), showing prominent recognition specificity and affinity among hundreds of aptamers for small molecules. Why OBA36 has >100-fold higher binding affinity to OTA than OTB remains a long-standing question due to the lack of high-resolution structure. Here we report the solution NMR structure of the aptamer–OTA complex. It was found that OTA binding induces the aptamer to fold into a well-defined unique duplex–quadruplex structural scaffold stabilized by Mg2+ and Na+ ions. OTA does not directly interact with the G-quadruplex, but specifically binds at the junction between the double helix and G-quadruplex through π–π stacking, halogen bonding (X-bond), and hydrophobic interaction. OTB has the same binding site as OTA but lacks the X-bond. The strong X-bond formed between the chlorine atom of OTA and the aromatic ring of C5 is the key to discriminating the strong binding toward OTA. The present research contributes to a deeper insight of aptamer molecular recognition, reveals structural basis of the high-affinity binding of aptamers, and provides a foundation for further aptamer engineering and applications.
研究领域:
生物化学
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分子生物学
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结构生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Chemistry-X
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2025
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IF 8.2
Zi-Yue Wang,Yun-Zhe Ma,Xin-Yue Jiang,Chen-Ying Wang,Ying-Qiu Li,Yan Liang,Xi-Dong Ren,Li-Cheng Qin,Xiang-Zhong Zhao
Thermal processing could reduce tenderness of cooked tuna. Papain, bromelain and ficin were employed to solve this issue, and their tenderizing mechanisms were investigated. Protein profiles showed that macromolecular proteins in tuna were degraded into smaller fractions by proteases, which led to increases in the myofibrillar fragmentation index (MFI) values. All proteases reduced shear force and hardness but increased cooking loss of tuna (except ficin), accompanied by the formation of unevenly distributed pores in tuna microstructures. Compared with control, bromelain decreased shear force and hardness by 86.95 % and 58.25 %, showing the best tenderizing effect. Moreover, reduction in content of disulfide bonds, the primary molecular force in tuna network, also contributed to the improvement of tenderness. Additionally, the ordered structures (α-helix and β-sheet) were transformed to disordered structures (β-turn and random coil) by proteases. These findings showed that proteases could significantly enhance the tenderness of tuna, especially bromelain.
研究领域:
食品科学
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生物化学
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蛋白质组学
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质构分析
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酶学
✓ 已验证
DOI
PubMed
高影响因子
DYES AND PIGMENTS
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2025
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IF 4.2
Weilong Du,Jie Ren,Haonan Hu,Yan Zhao,Lei Cao,Dongjun Wang,Xiangkui Ren
In recent years, non-traditional intrinsic luminophores (NTILs) have garnered significant attention due to their ability to produce bright fluorescence after simple treatments. In this study, by employing a straightforward methodology of oxygen purging and controlled thermal treatment (40–120 °C), we demonstrated that non-traditional small-molecule amines (mainly diethylenetriamine, DETA) can exhibit rare dual fluorescence characteristics, including excitation-independent (EIF) and excitation-dependent (EDF) behaviors. More importantly, through structure characterization, fluorescence lifetime analysis, and simulation calculations, we confirmed the following structure-mechanism relationship underlying DETA luminescence: when pure DETA molecules were heated within the 40–80 °C, a stable dimeric structure (DETA-dimers) formed through hydrogen-bond interactions resulted in fluorescence centers exhibiting EIF characteristics. Notably, when the temperature increased further (80–120 °C), DETA-dimers in their excited state interact with oxygen molecules under external light, which formed dynamic excimers through space conjugation, denoted as [DETA-dimer … O 2 ], resulting in EDF phenomenon. Finally, capitalizing on DETA dual fluorescence properties, we successfully implemented EIF-based ion detection and EDF-enabled fluorescence staining applications. Consequently, this work advanced the mechanistic understanding of NTILs' intrinsic luminescence and established a framework for optimizing their performance in high-sensitivity fluorescence imaging and probe development.
研究领域:
材料科学
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物理化学
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有机化学
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荧光光谱学
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分析化学
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生物成像
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传感技术
✓ 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）