Publications by authors named "Yi-Fan Bao"

Reference electrode (RE) plays the core role in accurate potential control in electrochemistry. However, nanoresolved electrochemical characterization techniques still suffer from unstable potential control of pseudo-REs, because the commercial RE is too large to be used in the tiny electrochemical cell, and thus only pseudo-RE can be used. Therefore, microsized RE with a stable potential is urgently required to push the nanoresolved electrochemical measurements to a new level of accuracy and precision, but it is quite challenging to reproducibly fabricate such a micro RE until now.

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Materials and their interfaces are the core for the development of a large variety of fields, including catalysis, energy storage and conversion. In this case, tip-enhanced Raman spectroscopy (TERS), which combines scanning probe microscopy with plasmon-enhanced Raman spectroscopy, is a powerful technique that can simultaneously obtain the morphological information and chemical fingerprint of target samples at nanometer spatial resolution. It is an ideal tool for the nanoscale chemical characterization of materials and interfaces, correlating their structures with chemical performances.

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Collective excitations including plasmons, magnons, and layer-breathing vibration modes emerge at an ultralow frequency (<1 THz) and are crucial for understanding van der Waals materials. Strain at the nanoscale can drastically change the property of van der Waals materials and create localized states like quantum emitters. However, it remains unclear how nanoscale strain changes collective excitations.

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Despite great advances in protein structure analysis, label-free and ultrasensitive methods to obtain the natural and dynamic three-dimensional (3D) structures are still urgently needed. Surface-enhanced Raman spectroscopy (SERS) can be a good candidate, whereas the complexity originated from the interactions between the protein and the gradient surface electric field makes it extremely challenging to determine the protein structure. Here, we propose a deciphering strategy for accurate determination of 3D protein structure from experimental SERS spectra in seconds by simply summing SERS spectra of isolated amino acids in electric fields of different strength with their orientations in protein.

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Investigation of proteins in their native state is the core of proteomics towards better understanding of their structures and functions. Surface-enhanced Raman spectroscopy (SERS) has shown its unique advantages in protein characterization with fingerprint information and high sensitivity, which makes it a promising tool for proteomics. It is still challenging to obtain SERS spectra of proteins in the native state and evaluate the native degree.

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Solid phase extraction combined with ultra-performance liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of 31 endocrine-disrupting chemicals in fish plasma. The strong anion exchange/primary-secondary amine cartridge and the mixed cation exchange cartridge were used in tandem instead of using a single mixed cation exchange cartridge for sample purification. Suitable eluents were selected for each of the two cartridges: 4.

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Defects can locally tailor the electronic properties of 2D materials, including the band gap and electron density, and possess the merit for optical and electronic applications. However, it is still a great challenge to realize rational defect engineering, which requires quantitative study of the effect of defects on electronic properties under ambient conditions. In this work, we employed tip-enhanced photoluminescence (TEPL) spectroscopy to obtain the PL spectra of different defects (wrinkle and edge) in mechanically exfoliated thin-layer transition metal dichalcogenides (TMDCs) with nanometer spatial resolution.

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Revealing the intrinsic relationships between the structure, properties, and performance of the electrochemical interface is a long-term goal in the electrochemistry and surface science communities because it could facilitate the rational design of electrochemical devices. Achieving this goal requires in situ characterization techniques that provide rich chemical information and high spatial resolution. Electrochemical tip-enhanced Raman spectroscopy (EC-TERS), which provides molecular fingerprint information with nanometer-scale spatial resolution, is a promising technique for achieving this goal.

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Electrochemical tip-enhanced Raman spectroscopy (EC-TERS) is a powerful technique for the in situ study of the physiochemical properties of the electrochemical solid/liquid interface at the nanoscale and molecular level. To further broaden the potential window of EC-TERS while extending its application to opaque samples, here, we develop a top-illumination atomic force microscopy (AFM) based EC-TERStechnique by using a water-immersion objective of a high numerical aperture to introduce the excitation laser and collect the signal. This technique not only extends the application of EC-TERS but also has a high detection sensitivity and experimental efficiency.

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Defects can induce drastic changes of the electronic properties of two-dimensional transition metal dichalcogenides and influence their applications. It is still a great challenge to characterize small defects and correlate their structures with properties. Here, we show that tip-enhanced Raman spectroscopy (TERS) can obtain distinctly different Raman features of edge defects in atomically thin MoS, which allows us to probe their unique electronic properties and identify defect types (e.

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is a natural plant with high nutritional and pharmacological value. Leaves of contain a variety of active substances. In our previous research, we had obtained a polysaccharide separated from leaf, namely MOs-2-a (1.

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The article Occurrence of 25 pharmaceuticals in Taihu Lake and their removal from two urban drinking water treatment plants and a constructed wetland, written by Xia-Lin Hu, Yi-Fan Bao, Jun-Jian Hu, You-Yu Liu and Da-Qiang Yin, was originally published electronically on the publisher's internet portal.

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A confirmatory method for the simultaneous detection of 29 pharmaceuticals in fish muscle and plasma was developed by using solid-phase extraction combined with ultra-high performance liquid chromatography and tandem mass spectrometry. Fish samples were extracted with methanol and enriched using Oasis HLB solid-phase extraction columns in one step. Twenty-nine target pharmaceuticals were quantified by the internal standard method and the calibration curves showed good linearity in a wide range with determination coefficients of greater than 0.

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Pharmaceuticals in drinking water sources have raised significant concerns due to their persistent input and potential human health risks. The seasonal occurrence of 25 pharmaceuticals including 23 antibiotics, paracetamol (PAR), and carbamazepine (CMZ) in Taihu Lake was investigated; meanwhile, the distribution and removal of these pharmaceuticals in two drinking water treatment plants (DWTPs) and a constructed wetland were evaluated. A high detection frequency (>70%) in the Taihu Lake was observed for nearly all the 25 pharmaceutics.

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We investigated the ameliorative effects and potential mechanisms of tannic acid (TA) in carbon tetrachloride (CCl4)-intoxicated mice and hepatic stellate cells (HSCs). Liver fibrosis was observed in CCl4 (800 ml/kg)-induced mice, and high viability was observed in CCl4 (10 mM)-intoxicated HSCs. Pre-treatment of mice with TA (25 or 50 g/kg/day) significantly ameliorated hepatic morphology and coefficient values and reduced the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), the concentrations of malondialdehyde (MDA) and serum levels of endothelin-1 (ET-1).

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