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Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

《能源前沿（英文）》 2018年 第12卷 第1期   页码 43-71 doi: 10.1007/s11708-018-0524-8

摘要： Vibrational spectroscopy is one of the key instrumentations that provide non-invasive investigation of structural and chemical composition for both organic and inorganic materials. However, diffraction of light fundamentally limits the spatial resolution of far-field vibrational spectroscopy to roughly half the wavelength. In this article, we thoroughly review the integration of atomic force microscopy (AFM) with vibrational spectroscopy to enable the nanoscale characterization of emerging energy materials, which has not been possible with far-field optical techniques. The discussed methods utilize the AFM tip as a nanoscopic tool to extract spatially resolved electronic or molecular vibrational resonance spectra of a sample illuminated by a visible or infrared (IR) light source. The absorption of light by electrons or individual functional groups within molecules leads to changes in the sample’s thermal response, optical scattering, and atomic force interactions, all of which can be readily probed by an AFM tip. For example, photothermal induced resonance (PTIR) spectroscopy methods measure a sample’s local thermal expansion or temperature rise. Therefore, they use the AFM tip as a thermal detector to directly relate absorbed IR light to the thermal response of a sample. Optical scattering methods based on scanning near-field optical microscopy (SNOM) correlate the spectrum of scattered near-field light with molecular vibrational modes. More recently, photo-induced force microscopy (PiFM) has been developed to measure the change of the optical force gradient due to the light absorption by molecular vibrational resonances using AFM’s superb sensitivity in detecting tip-sample force interactions. Such recent efforts successfully breech the diffraction limit of light to provide nanoscale spatial resolution of vibrational spectroscopy, which will become a critical technique for characterizing novel energy materials.

关键词： vibrational spectroscopy     atomic force microscopy     photo-thermal induced resonance     scanning near-field optical microscopy     tip-enhanced Raman spectroscopy     photo-induced force microscopy     molecular resonances     surface phonon polaritons     energy materials    

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Photo-induced surface frustrated Lewis pairs for promoted photocatalytic decomposition of perfluorooctanoic

《环境科学与工程前沿（英文）》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1603-6

摘要：

● Terminal carboxylate group activation is PFOA degradation’s rate-limiting step.

关键词： Heterogeneous photocatalysis     Surface frustrated Lewis pairs     Perfluorooctanoic acid     Defluorination efficiency     Environmental remediation    

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Applications of atomic force microscopy in immunology

Jiping Li, Yuying Liu, Yidong Yuan, Bo Huang

《医学前沿（英文）》 2021年 第15卷 第1期   页码 43-52 doi: 10.1007/s11684-020-0769-6

摘要： Cellular mechanics, a major regulating factor of cellular architecture and biological functions, responds to intrinsic stresses and extrinsic forces exerted by other cells and the extracellular matrix in the microenvironment. Cellular mechanics also acts as a fundamental mediator in complicated immune responses, such as cell migration, immune cell activation, and pathogen clearance. The principle of atomic force microscopy (AFM) and its three running modes are introduced for the mechanical characterization of living cells. The peak force tapping mode provides the most delicate and desirable virtues to collect high-resolution images of morphology and force curves. For a concrete description of AFM capabilities, three AFM applications are discussed. These applications include the dynamic progress of a neutrophil-extracellular-trap release by neutrophils, the immunological functions of macrophages, and the membrane pore formation mediated by perforin, streptolysin O, gasdermin D, or membrane attack complex.

关键词： cellular mechanics     atomic force microscopy     neutrophil extracellular trap     macrophage phagocytosis     pore formation    

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Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 105-111 doi: 10.1007/s11705-019-1791-6

摘要： The synthesis of -cyclohexyl carbamate-attached fluorene- -phenylene copolymer (PFPNCC) and the use of PFPNCC as a “ligand-free” fluorescent chemosensor for Cu(II) are described. Addition of Cu(II) can efficiently quench the fluorescence of PFPNCC in nucleophilic solvents such as DMF and DMSO, but not in low nucleophilic solvents such as 1,4-dioxane and THF. Ultraviolet-visible spectra of the mixture of the conjugated polymer and Cu(II) indicate the presence of a reduced Cu(I) ion in the solution. Furthermore, fluorescence recovery of PFPNCC observed at low temperature suggests that the quenching and reducing mechanism is most probably due to a photo-induced electron transfer from excited PFPNCC to Cu(II). Our findings provide a novel strategy for highly selective conjugated polymer-based chemosensors for various target analytes, albeit “ligand-free”.

关键词： ligand-free     fluorescent chemosensor     copper     photo-induced electron transfer    

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Shape and topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic forcemicroscopy cantilever probe

Qi XIA,Tao ZHOU,Michael Yu WANG,Tielin SHI

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 50-57 doi: 10.1007/s11465-014-0286-x

摘要：

In an operation mode of atomic force microscopy that uses a higher eigenmode to determine the physical properties of material surface, the ratio between the eigenfrequency of a higher flexural eigenmode and that of the first flexural eigenmode was identified as an important parameter that affects the sensitivity and accessibility. Structure features such as cut-out are often used to tune the ratio of eigenfrequencies and to enhance the performance. However, there lacks a systematic and automatic method for tailoring the ratio. In order to deal with this issue, a shape and topology optimization problem is formulated, where the ratio between two eigenfrequencies is defined as a constraint and the area of the cantilever is maximized. The optimization problem is solved via the level set based method.

关键词： atomic force microscopy     cantilever probe     eigenfrequency     optimization    

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Hypoxia-induced activity loss of a photo-responsive microtubule inhibitor azobenzene combretastatin A4

Yang An, Chao Chen, Jundong Zhu, Pankaj Dwivedi, Yanjun Zhao, Zheng Wang

《化学科学与工程前沿（英文）》 2020年 第14卷 第5期   页码 880-888 doi: 10.1007/s11705-019-1864-6

摘要： The conformation-dependent activity of azobenzene combretastatin A4 (Azo-CA4) provides a unique approach to reduce the side-effects of chemotherapy, due to the light-triggered conformation transition of its azobenzene moiety. Under hypoxic tumor microenvironment, however, the high expression of azoreductase can reduce azobenzene to aniline. It was postulated that the Azo-CA4 might be degraded under hypoxia, resulting in the decrease of its anti-tumor activity. The aim of this study was to verify such hypothesis in HeLa cells . The quantitative drug concentration analysis shows the ratiometric formation of degradation end-products, confirming the bioreduction of Azo-CA4. The tubulin staining study indicates that Azo-CA4 loses the potency of switching off microtubule dynamics under hypoxia. Furthermore, the cell cycle analysis shows that the ability of Azo-CA4 to induce mitotic arrest is lost at low oxygen content. Therefore, the cytotoxicity of Azo-CA4 is compromised under hypoxia. In contrast, combretastatin A4 as a positive control maintains the potency to inhibit tubulin polymerization and break down the nuclei irrespective of light irradiation and oxygen level. This work highlights the influence of hypoxic tumor microenvironment on the anti-tumor potency of Azo-CA4, which should be considered during the early stage of designing translational Azo-CA4 delivery systems.

关键词： hypoxia     microtubule inhibitor     drug delivery     azo-combretastatin A4     photo-responsive    

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Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous

GUO Jin, MA Jun, SHI Xuehua

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 251-256 doi: 10.1007/s11783-007-0043-z

摘要： To understand the water purification mechanism of potassium permanganate as a coagulation-aid during the preoxidation process, the microtopography of its reductive products, the newly formed hydrous manganese dioxide and the aged hydrous manganese dioxide, was investigated. The morphology of natural organic matter (NOM) adsorbed by the newly formed hydrous manganese dioxide was also compared with that of NOM alone. By using the tapping mode atomic force microscopy (AFM), the observation results show that the newly formed hydrous manganese dioxide possess a perforated sheet (with a thickness of 0 1.75 nm) as well as some spherical particle structures compared with the hydrous manganese dioxide with 2 h aging time, which demonstrated that the newly formed hydrous manganese dioxide had a large surface area and adsorption capacity. When 1 mmol/L newly formed hydrous manganese dioxide was added, the microtopography of NOM molecules shifted from a loosely dispersed pancake shape (with adsorption height of 5 8.5 nm) to a densely dispersed and uniform spherical structure. These results provide a valid proof that it is the perfect adsorption capability of the newly formed hydrous manganese dioxide that might result in the coagulation aid effect of potassium permanganate preoxidation.

关键词： spherical     microtopography     potassium permanganate     uniform spherical     morphology    

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Experimental and computational assessment of 1,4-Dioxane degradation in a photo-Fenton reactive ceramic

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1341-y

摘要：

• 1,4-Dioxane was degraded via the photo-Fenton reactive membrane filtration.

关键词： Photo-Fenton     Ceramic membrane     1     4-Dioxane     Goethite    

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用于预测涡振稳态振幅的箱梁竖向涡激力简化非线性模型

朱乐东, 孟晓亮, 杜林清, 丁明畅

《工程（英文）》 2017年 第3卷 第6期   页码 854-862 doi: 10.1016/j.eng.2017.06.001

摘要：
采用同步测力测振大比例节段模型风洞试验方法，研究了作用在全封闭、半封闭和中央开槽三种典型箱梁上竖向涡激力的非线性特性，通过分析竖向涡激力不同成分的能量演化规律和对涡振响应的贡献，探索了竖向涡激共振的起振、发展和自限幅的机理。结果显示：不同类型箱梁的竖向涡激力的非线性成分通常会有所不同，但控制竖向涡激振动稳态响应幅值的最重要涡激力成分都是速度一次线性和三次非线性气动阻尼力成分。前者向振动系统提供了一个恒定的负气动阻尼比，因而是驱动涡振振幅发展的根本动力，而后者则向系统提供了一个与涡振速度平方成正比的正气动阻尼比，从而实质上成为导致涡振自限幅现象的内在因素。有鉴于此，本文提出了一个能高精度预测大跨度桥梁涡振稳态振幅的箱梁断面竖向涡激力通用简化非线性数学模型，并进行了验证。

关键词： 箱形桥梁     竖向涡激振动     竖向涡激力     简化非线性模型     风洞试验     大比例节段模型     同步测力测振    

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Aerodynamic impact of train-induced wind on a moving motor-van

Jiajun HE; Huoyue XIANG; Yongle LI; Bin HAN

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 909-927 doi: 10.1007/s11709-022-0833-1

摘要： The newly-built single-level rail-cum-road bridge brings the issue of the aerodynamic impact of train-induced wind on road automobiles. This research introduced a validated computational fluid dynamics (CFD) model regarding this concern. Such an aerodynamic impact mechanism was explored; a relationship between the transverse distance between train and motor-van (hereinfafter referred to as van) and the aerodynamic effects on the van was explored to help the optimization of bridge decks, and the relationship between the automobile speed and aerodynamic variations of a van was fitted to help traffic control. The fitting results are accurate enough for further research. It is noted that the relative speed of the two automobiles is not the only factor that influences the aerodynamic variations of the van, even at a confirmed relative velocity, the aerodynamic variations of the van vary a lot as the velocity proportion changes, and the most unfavorable case shows an increase of over 40% on the aerodynamic variations compared to the standard case. The decay of the aerodynamic effects shows that not all the velocity terms would enhance the aerodynamic variations; the coupled velocity term constrains the variation amplitude of moments and decreases the total amplitude by 20%–40%.

关键词： rail-cum-road bridge     aerodynamic impact     train-induced wind     CFD     aerodynamic force     quantitative analysis     fitting    

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Selective reduction of NO by photo-SCR with ammonia in an annular fixed-film photoreactor

YiangChen CHOU, Young KU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 149-155 doi: 10.1007/s11783-010-0296-9

摘要： Gaseous NO was photocatalytically reduced at room temperature by photo-assisted selective catalytic reduction (photo-SCR) with ammonia over TiO in this study. NO reduction efficiency and N selectivity were determined from gases composition at the outlet stream of photoreactor. Effect of operating conditions, e.g. light intensity and inlet concentrations of ammonia and oxygen, on the NO reduction efficiency and N selectivity were discussed to determine the feasible operating condition for photocatalytic reduction of NO. Experimental results showed that selective catalytic reduction of NO with ammonia over TiO in the presence of oxygen was a spontaneous reaction in dark. The photoirradiation on the TiO surface caused remarkable photocatalytic reduction of NO to form N , NO , and N O under 254 nm UV illuminations, while almost 90% of N selectivity was achieved in this study. The ammonia and oxygen molecules played the roles of reductant and oxidant for NO reduction and active sites regeneration, respectively. The reduction of NO was found to be increased with the increase of inlet ammonia and oxygen concentrations until specific concentrations because of the limited active sites on the surface of TiO . The kinetic model proposed in this study can be used to reasonably describe the reaction mechanism of photo-SCR.

关键词： photo-SCR     photocatalysis     NO reduction     Eley-Rideal model    

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Lignin-based electrospun nanofiber membrane decorated with photo-Fenton Ag@MIF-100(Fe) heterojunctions

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 930-941 doi: 10.1007/s11705-023-2309-9

摘要： Membrane technology for wastewater remediation has aroused wide interest owing to its unique properties and potential applications. However, it remains challenging to explore green, efficient and robust membrane material and technique for complex wastewater treatment. Herein, we proposed using a simple electrospinning and in situ seeding method to fabricate a lignin-based electrospun nanofiber membrane (LENM) decorated with photo-Fenton Ag@MIL-100(Fe) heterojunctions for efficient separation of oil/water emulsions and degradation of organic dye. Thanks to the embedded lignin in LENM, an ultrahigh MIL-100(Fe) loading (53 wt %) with good wettability and high porosity was obtained. As a result, the hybrid Ag@MIL-100(Fe)/LENM exhibited excellent oil/water emulsions separation efficiency (more than 97%) without a compromise of water flux. Moreover, the hybrid membrane showed an excellent dye removal with degradation of 99% methylene blue within 30 min under illumination, which is attributed to a synergy of dye adsorption/enrichment and photo-Fenton catalytic degradation from Ag@MIL-100(Fe). Therefore, the lignin-based photo-Fenton hybrid membrane can lay the foundation for the preparation and application of green, sustainable and versatile membrane materials and technologies for efficient complex wastewater remediation.

关键词： lignin     electrospinning     heterojunctions     photo-Fenton catalysis     wastewater remediation    

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木质素磺酸盐/二氧化硅无机颗粒体系中的原子力显微镜力学测试——从分散机理研究到产品设计 Article

王静禹, 钱勇, 周义杰, 杨东杰, 邱学青

《工程（英文）》 2021年 第7卷 第8期   页码 1140-1148 doi: 10.1016/j.eng.2021.07.004

摘要：

设计和制备高性能木质素基分散剂是实现木质素工程化高值利用的关键。这一过程很大程度上取决于对木质素基分散剂分散机理的理解。本文通过原子力显微镜（AFM）量化研究了木质素磺酸盐/二氧化硅（LS/SiO2）体系在不同pH条件下的分散机理。结果表明，SiO2颗粒之间在LS溶液中比在水中有更强的排斥力，因此具有更好的分散稳定性。分别使用Derjaguin-Landau-Verwey-Overbeek (DLVO)理论以及结合空间位阻排斥力的DLVO理论方程对水中和LS溶液中的SiO2探针与基材之间的AFM力/距离曲线（F/D）进行拟合。基于拟合结果，分别计算出静电排斥力和空间位阻排斥力，证明LS在SiO2粒子之间提供了较强的空间位阻排斥力。进一步研究证明，LS在SiO2上的吸附量（Q）、归一化作用常数（A）和特征长度（L）是影响LS/SiO2体系空间位阻排斥力的三个关键因素。基于上述研究，设计并制备了新型季铵化接枝磺化木质素基分散剂（QAGSL）。QAGSL对SiO2和真实水泥颗粒均具有良好的分散性能。相关研究既为LS/无机颗粒体系中的分散机理提供了基础和定量的理解，也为高性能木质素基分散剂的开发提供了重要的技术指导。

关键词： 木质素     二氧化硅     原子力显微镜     分散机理     产品设计    

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Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene and carbazole

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 192-195 doi: 10.1007/s11705-009-0015-x

摘要： Two donor-σ-acceptor molecules containing tetrathiafulvalene (TTF) and carbazole moieties were synthesized by the reaction of 9-(4-bromo-butyl)-carbazole ( ) with 2,6-bis(hexylthio)-3-(2-cyanoethylthio)-7-(methylthio)-tetrathiafulvalene ( ) or 2,6-bis(2-cyanoethylthio)-3,7-bis(methylthio)tetrathiafulvalene ( ) in the presence of CsOH·H O, respectively. The structures of the molecules were characterized by H NMR, C NMR, MS, and elemental analyses. They showed negligible intramolecular charge-transfer interaction in their ground states as indicated by their UV-Vis spectroscopics and cyclic voltammetry results. Compared with carbazole, their fluorescence was strongly quenched, which implied that a photo induced electron transfer (PET) interaction between TTF and carbazole moieties occurred.

关键词： donor-σ-acceptor molecule     intramolecular charge transfer interaction     photo induced electron transfer     tetrathiafulvalene     carbazole    

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Insight into the role of cholesterol in modulation of morphology and mechanical properties of CHO-K1 cells: An in situ AFM study

Lei Zhang, Lisha Zhao, Ping-Kai Ouyang, Pu Chen

《化学科学与工程前沿（英文）》 2019年 第13卷 第1期   页码 98-107 doi: 10.1007/s11705-018-1775-y

摘要：

Cholesterol plays a significant role in the organization of lipids and modulation of membrane dynamics in mammalian cells. However, the effect of cholesterol depletion on the eukaryotic cell membranes seems controversial. In this study, the effects of cholesterol on the topography and mechanical behaviors of CHO-K1 cells with manipulated membrane cholesterol contents were investigated by atomic force microscopy (AFM) technique. Here, we found that the depletion of cholesterol in cell membranes could increase the membrane stiffness, reduce the cell height as well as promote cell retraction and detachment from the surface, whereas the cholesterol restoration could reverse the effect of cholesterol depletion on the membrane stiffness. Increased methyl-β-cyclodextrin levels and incubation time could significantly increase Young’s modulus and degree of stiffing on cell membrane and cytoskeleton. This research demonstratede importance of cholesterol in regulating the dynamics of cytoskeleton-mediated processes. AFM technique offers excellent advantages in the dynamic monitoring of the change in membranes mechanical properties and behaviors during the imaging process. This promising technology can be utilized in studying the membrane properties and elucidating the underlying mechanism of distinct cells in the near-native environment.

关键词： cholesterol     methyl-β-cyclodextrin     atomic force microscopy     Young’s modulus     CHO-K1 cell    

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标题 作者 时间 类型 操作

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

期刊论文

Photo-induced surface frustrated Lewis pairs for promoted photocatalytic decomposition of perfluorooctanoic

期刊论文

Applications of atomic force microscopy in immunology

Jiping Li, Yuying Liu, Yidong Yuan, Bo Huang

期刊论文

Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

期刊论文

Shape and topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic forcemicroscopy cantilever probe

Qi XIA,Tao ZHOU,Michael Yu WANG,Tielin SHI

期刊论文

Hypoxia-induced activity loss of a photo-responsive microtubule inhibitor azobenzene combretastatin A4

Yang An, Chao Chen, Jundong Zhu, Pankaj Dwivedi, Yanjun Zhao, Zheng Wang

期刊论文

Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous

GUO Jin, MA Jun, SHI Xuehua

期刊论文

Experimental and computational assessment of 1,4-Dioxane degradation in a photo-Fenton reactive ceramic

期刊论文

用于预测涡振稳态振幅的箱梁竖向涡激力简化非线性模型

朱乐东, 孟晓亮, 杜林清, 丁明畅

期刊论文

Aerodynamic impact of train-induced wind on a moving motor-van

Jiajun HE; Huoyue XIANG; Yongle LI; Bin HAN

期刊论文

Selective reduction of NO by photo-SCR with ammonia in an annular fixed-film photoreactor

YiangChen CHOU, Young KU

期刊论文

Lignin-based electrospun nanofiber membrane decorated with photo-Fenton Ag@MIF-100(Fe) heterojunctions

期刊论文

木质素磺酸盐/二氧化硅无机颗粒体系中的原子力显微镜力学测试——从分散机理研究到产品设计

王静禹, 钱勇, 周义杰, 杨东杰, 邱学青

期刊论文

Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene and carbazole

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

期刊论文

Insight into the role of cholesterol in modulation of morphology and mechanical properties of CHO-K1 cells: An in situ AFM study

Lei Zhang, Lisha Zhao, Ping-Kai Ouyang, Pu Chen

期刊论文