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期刊论文 41

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关键词

原子力显微镜 4

纳米加工 2

360°表征 1

SIM 1

三维原子力显微镜 1

三维形貌重建 1

乳液 1

二次谐波产生（SHG）-SIM 1

二氧化硅 1

产品设计 1

光学活检 1

共聚焦内窥镜 1

关键尺寸 1

分子间和表面间相互作用 1

分散机理 1

单晶铜 1

周期性纳米结构 1

多光子结构光照明超分辨显微成像 1

宫内节育器；盆腔炎性疾病；细菌生物膜；SEM 1

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Characterization of particle deposition during crossflow filtration as influenced by permeate flux and crossflow velocity using a microfluidic filtration system

Hongzhan Di, Gregory J. O. Martin, Dave E. Dunstan

《化学科学与工程前沿（英文）》 2021年第15卷第3期页码 552-561 doi: 10.1007/s11705-020-1962-5

摘要： Particle deposition during crossflow filtration is significantly influenced by the operating conditions, in particular the permeate flux and crossflow velocity. However, there is a lack of detailed knowledge about how deposit layer structures and distributions depend on operating parameters. This study uses a microfluidic visualisation filtration system to examine the influence of operating conditions on the deposition process during crossflow ultrafiltration from a microscopic perspective. Increasing the permeate flux caused an increasing amount of deposition and a thicker deposit layer. Higher crossflow velocities reduced the extent of deposition. The degree of deposition varied over a range of operating conditions due to the altered hydrodynamic forces exerted on the particles, which can be examined by the deposition probability according to an existing model. Building on this, an empirical correlation between the deposition probability and volume of deposition as function of filtration time was developed, which gave good agreement with experimental results. The effect of solution conditions was also involved in this correlation as a interaction energies. This could be useful for predicting the dynamic deposition process during crossflow filtration over a range of operating and solution conditions.

关键词： particle deposition crossflow filtration microfluidics confocal microscopy

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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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Chemical mapping of cement pastes by using confocal Raman spectroscopy

Fengjuan LIU,Zhihui SUN

《结构与土木工程前沿（英文）》 2016年第10卷第2期页码 168-173 doi: 10.1007/s11709-015-0323-9

摘要： In the present study, chemical mapping on the hydration process of cement paste with water-to-cement ( / ) ratio of 0.60 was implemented by Raman spectroscopy (RS). The RS was applied to study the paste from 12 hours after mixing to 28 days. Cement ingredients and hydration products, including calcium silicates (C S and C S), calcium hydroxide (CH), and ettringite, were quantitatively studied. From the research, it is observed that calcium silicates were consumed gradually with the increased hydration age. Calcium hydroxide increased and tended to cluster in the pore vicinity during hydration. Ettringite was found to form on the surface of the unreacted particles, which was shown as a mixed zone of ettringite and calcium silicates in the maps. It is concluded from the study that chemical mapping was an effective method to assist in visualizing particle dispersion and connection on top of the quantitative analysis.

关键词： chemical mapping Raman spectroscopy calcium silicates calcium hydroxide ettringite

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topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic force microscopy

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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4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomal cellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

《化学科学与工程前沿（英文）》 2020年第14卷第1期页码 61-75 doi: 10.1007/s11705-019-1862-8

摘要： Four new fluorescent sensors ( - ) based on the 4-amino-1,8-naphthalimide fluorophores ( ) have been synthesized based on the classical fluorophore-spacer-receptor model. These four compounds all gave rise to emission bands centred at 535 nm, which were found to be highly pH dependent, the emission being ‘switched on’ in acidic media, while being quenched due to PET from the amino moieties to the excited state of the at more alkaline pH. The luminescent pH dependence for these probes was found to be highly dependent on the substitution on the imide site, as well as the polyamine chain attached to the position 4-amino moiety. In the case of sensor the presence of the 4-amino-aniline dominated the pH dependent quenching. Nevertheless, at higher pH, PET quenching was also found to occur from the polyamine site. Hence, is better described as a receptor -spacer -fluorophore-spacer -receptor system, where the dominant PET process is due to (normally less favourable) ‘directional’ PET quenching from the 4-amino-aniline unit to the site. Similar trends and pH fluorescence dependences were also seen for and . These compounds were also tested for their imaging potential and toxicity against HeLa cells (using DRAQ5 as nuclear stain which does now show pH dependent changes in acidic and neutral pH) and the results demonstrated that these compounds have reduced cellular viability at moderately high concentrations (with IC values between ca. 8‒30 µmol∙L ), but were found to be suitable for intracellular pH determination at 1 µmol∙L concentrations, where no real toxicity was observed. This allowed us to employ these as lysosomal probes at sub-toxic concentrations, where the based emission was found to be pH depended, mirroring that seen in aqueous solution for , with the main fluorescence changes occurring within acidic to neutral pH.

关键词： sensors pH photoinduced electron transfer cellular imaging confocal microscopy

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Three-dimensional reconstruction of light microscopy image sections: present and future

null

《医学前沿（英文）》 2015年第9卷第1期页码 30-45 doi: 10.1007/s11684-014-0337-z

摘要：

Three-dimensional (3D) image reconstruction technologies can reveal previously hidden microstructures in human tissue. However, the lack of ideal, non-destructive cross-sectional imaging techniques is still a problem. Despite some drawbacks, histological sectioning remains one of the most powerful methods for accurate high-resolution representation of tissue structures. Computer technologies can produce 3D representations of interesting human tissue and organs that have been serial-sectioned, dyed or stained, imaged, and segmented for 3D visualization. 3D reconstruction also has great potential in the fields of tissue engineering and 3D printing. This article outlines the most common methods for 3D tissue section reconstruction. We describe the most important academic concepts in this field, and provide critical explanations and comparisons. We also note key steps in the reconstruction procedures, and highlight recent progress in the development of new reconstruction methods.

关键词： microtomy 3D imaging computer-assisted image processing 3D printing tissue scaffold

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用于细胞成像的共聚焦内窥镜 Article

王家福,杨敏,杨莉,张云,袁菁,刘谦,侯晓华,付玲

《工程（英文）》 2015年第1卷第3期页码 351-360 doi: 10.15302/J-ENG-2015081

摘要：

使用内窥镜的目的是实现与组织病理诊断相符的即时诊断。在过去的十年里，共聚焦激光扫描显微成像技术被引入内窥镜领域。共聚焦内窥镜使得对活体组织的显微观察能够达到与组织学样品的体外显微成像相当的放大倍数和分辨率。发展这种内窥镜的主要挑战在于具有微米级分辨率的显微成像光纤探头的小型化。笔者研制了一套基于光纤束，分辨率为1.4 μm，成像速度可达8 fps的共聚焦内窥镜系统。光纤探头的直径为2.6 mm，可与常规内窥镜的活检通道兼容。该共聚焦内窥镜的样机已经被用于观察小鼠胃肠道上皮细胞，并将进一步被用于临床试验。此外，该共聚焦内窥镜能够被用于上皮细胞功能的转化研究，以监测自然生理环境中细微颗粒的功能和细胞间的相互作用。

关键词：细胞分辨率共聚焦内窥镜光学活检

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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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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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基于谐波的多光子扫描结构光照明超分辨显微成像

汪磊, 郑晓敏, 周洁, 王美婷, 陈嘉杰, 曾佑君, 许改霞, 王颖, 邱海霞, 邵永红, 屈军乐, 高志, 顾瑛

《工程（英文）》 2022年第16卷第9期页码 65-72 doi: 10.1016/j.eng.2021.12.010

摘要： style="text-align: justify;">本文提出了一种利用多光子非线性效应的多光子结构光照明超分辨显微成像（multiphoton-structured illumination microscopy

关键词：超分辨显微成像结构光照明超分辨显微成像多光子结构光照明超分辨显微成像 SIM 二次谐波产生（SHG）-SIM

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Surface modification of cellulose nanocrystals

WANG Neng, DING Enyong, CHENG Rongshi

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 228-232 doi: 10.1007/s11705-007-0041-5

摘要： In order to improve the dispersibility of cellulose nanocrystal (CNC) particles, three different grafted reactions of acetylation, hydroxyethylation and hydroxypropylation were introduced to modify the CNC surface. The main advantages of these methods were the simple and easily controlled reaction conditions, and the dispersibility of the resulting products was distinctly improved. The properties of the modified CNC were characterized by means of Fourier transform infrared spectroscopy (FT-IR), C nuclear magnetic resonance (NMR), transmission electron microscopy (TEM) and thermogravimetric analyses (TGA). The results indicated that after desiccation, the modification products could be dispersed again in the proper solvents by ultrasonic treatments, and the diameter of their particles had no obvious changes. However, their thermal degradation behaviors were quite different. The initial decomposition temperature of the modified products via hydroxyethylation or hydroxypropylation was lower than that of modified products via acetylation.

关键词： acetylation degradation transform microscopy desiccation

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Analysis of behavior of melted dark green silty soil

TANG Yiqun, ZHOU Nianqing, YANG Ping, SHEN Feng

《结构与土木工程前沿（英文）》 2008年第2卷第3期页码 242-245 doi: 10.1007/s11709-008-0022-x

摘要： The behavior of dark green silty soil of the 6th storey is studied by means of scanning electron microscopy (SEM). The shape, size and contact condition of the basic elements of the soil microstructure, and the shape and the size of the pore are further studied. In addition, a comparative study is made to analyze the experiment results of Cu and dynamic test. The mechanic characteristics of common soil and those of melted soil are presented and their influences on dark silty soil after being frozen are theoretically illustrated from a microscopic perspective.

关键词： electron microscopy mechanic microscopic perspective addition dynamic

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光学显微镜分辨率提升至亚纳米级

Chris Palmer

《工程（英文）》 2023年第31卷第12期页码 11-14 doi: 10.1016/j.eng.2023.11.002

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Preparation of solar selective absorbing CuO coating for medium temperature application

HUANG Qunwu, WANG Yiping, LI Jinhua

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 256-260 doi: 10.1007/s11705-007-0046-0

摘要： A new method of preparing CuO solar selective absorbing coating for medium temperature is presented. After pretreatment, brass was overlaid with CuO by chemical plating. The effects of reactant concentration, reaction temperature and reaction time on the absorptivity of CuO coating were investigated. The optimized condition of preparing CuO coating was obtained. The CuO coating was analyzed with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). In order to prolong the period of use, the CuO coating was protected by TiO. The experiment shows that the TiO/CuO coating is more heat-resistant, acid-resistant, and wear resistant than CuO coating, without losing absorptivity markedly. The TiO coating can reduce emissivity and protect the CuO coating.

关键词： photoelectron spectroscopy temperature pretreatment absorptivity microscopy

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Visualization of vascular ultrastructure during osteogenesis by tissue engineering technique

ZHANG Kaigang, ZENG Bingfang, ZHANG Changqing

《医学前沿（英文）》 2007年第1卷第2期页码 181-184 doi: 10.1007/s11684-007-0034-2

摘要： The aim of this paper was to observe and visualize the changes in osteoblasts by electron microscopy during osteogenesis using tissue engineering technique. We also studied the feasibility of improving tissue vascularization of th

关键词： feasibility engineering osteogenesis vascularization microscopy

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标题作者时间类型操作

Characterization of particle deposition during crossflow filtration as influenced by permeate flux and crossflow velocity using a microfluidic filtration system

Hongzhan Di, Gregory J. O. Martin, Dave E. Dunstan

期刊论文

Applications of atomic force microscopy in immunology

Jiping Li, Yuying Liu, Yidong Yuan, Bo Huang

期刊论文

Chemical mapping of cement pastes by using confocal Raman spectroscopy

Fengjuan LIU,Zhihui SUN

期刊论文

topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic force microscopy

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

期刊论文

4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomal cellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

期刊论文

Three-dimensional reconstruction of light microscopy image sections: present and future

null

期刊论文

用于细胞成像的共聚焦内窥镜

王家福,杨敏,杨莉,张云,袁菁,刘谦,侯晓华,付玲

期刊论文

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

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

期刊论文

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