Artykuły w czasopismach: „AFM Modes”

1

Cruz Valeriano, Edgar, José Juan Gervacio Arciniega, Christian Iván Enriquez Flores, Susana Meraz Dávila, Joel Moreno Palmerin, Martín Adelaido Hernández Landaverde, Yuri Lizbeth Chipatecua Godoy, Aime Margarita Gutiérrez Peralta, Rafael Ramírez Bon i José Martín Yañez Limón. "Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach". Beilstein Journal of Nanotechnology 11 (4.05.2020): 703–16. http://dx.doi.org/10.3762/bjnano.11.58.

Pełny tekst źródła

Streszczenie:

In this work, a high-resolution atomic force acoustic microscopy imaging technique is developed in order to obtain the local indentation modulus at the nanoscale level. The technique uses a model that gives a qualitative relationship between a set of contact resonance frequencies and the indentation modulus. It is based on white-noise excitation of the tip–sample interaction and uses system theory for the extraction of the resonance modes. During conventional scanning, for each pixel, the tip–sample interaction is excited with a white-noise signal. Then, a fast Fourier transform is applied to the deflection signal that comes from the photodiodes of the atomic force microscopy (AFM) equipment. This approach allows for the measurement of several vibrational modes in a single step with high frequency resolution, with less computational cost and at a faster speed than other similar techniques. This technique is referred to as stochastic atomic force acoustic microscopy (S-AFAM), and the frequency shifts of the free resonance frequencies of an AFM cantilever are used to determine the mechanical properties of a material. S-AFAM is implemented and compared with a conventional technique (resonance tracking-atomic force acoustic microscopy, RT-AFAM). A sample of a graphite film on a glass substrate is analyzed. S-AFAM can be implemented in any AFM system due to its reduced instrumentation requirements compared to conventional techniques.

Style APA, Harvard, Vancouver, ISO itp.

2

Eby, R. K., R. L. McEvoy i S. Marchese-Ragona. "AFM of polymers using force spectroscopy modes". Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 1076. http://dx.doi.org/10.1017/s042482010017311x.

Pełny tekst źródła

Streszczenie:

Several novel imaging modes in scanning-probe microscopy are capable of imaging the surface compliance properties of polymers. The atomic-force microscope is used with a silicon nitride cantilever, in contact mode. While scanning, the tip can be modulated with a low amplitude (25 Å) and low frequency (5 kHz), and the amplitude of tip deflection is compared with the input modulation signal. This mode, called modulated force, maps out the surface compliance of a sample, and gives pixel-to-pixel matching with a topography mode image. Alternatively, while scanning a topography mode image, a force-distance curve can be performed at each x-y pixel location. Several data points in the z-direction of the dF-dS curve can therefore be collected at each x-y data position. In result, one obtains a 3D dataset of force-distance curves with corresponding topography data. The dF-dS images that result are slices through the force-distance regime, each with pixel-to-pixel correspondence to the topography image. In this study, various polymer systems are examined with AFM force imaging modes.

Style APA, Harvard, Vancouver, ISO itp.

3

Dillon, Eoghan, Kevin Kjoller i Craig Prater. "Lorentz Contact Resonance Imaging for Atomic Force Microscopes: Probing Mechanical and Thermal Properties on the Nanoscale". Microscopy Today 21, nr 6 (listopad 2013): 18–24. http://dx.doi.org/10.1017/s1551929513000989.

Pełny tekst źródła

Streszczenie:

Atomic force microscopy (AFM) has been widely used in both industry and academia for imaging the surface topography of a material with nanoscale resolution. However, often little other information is obtained. Contact resonance AFM (CR-AFM) is a technique that can provide information about the viscoelastic properties of a material in contact with an AFM probe by measuring the contact stiffness between the probe and sample. In CR-AFM, an AFM cantilever is oscillated, and the amplitude and frequency of the resonance modes of the cantilever are monitored. When a probe or sample is oscillated, the tip sample interaction can be approximated as an ideal spring-dashpot system using the Voigt-Kelvin model shown in Figure 1. Contact resonance frequencies of the AFM cantilever will shift depending on the contact stiffness, k, between the tip and sample. The damping effect on the system comes from dissipative tip sample forces such as viscosity and adhesion. Damping, η, is observed in a CR-AFM system by monitoring the amplitude and Q factor of the resonant modes of the cantilever. This contact stiffness and damping information can then be used to obtain information about the viscoelastic properties of the material when fit to an applicable model.

Style APA, Harvard, Vancouver, ISO itp.

4

Xia, Fangzhou, i Kamal Youcef-Toumi. "Review: Advanced Atomic Force Microscopy Modes for Biomedical Research". Biosensors 12, nr 12 (2.12.2022): 1116. http://dx.doi.org/10.3390/bios12121116.

Pełny tekst źródła

Streszczenie:

Visualization of biomedical samples in their native environments at the microscopic scale is crucial for studying fundamental principles and discovering biomedical systems with complex interaction. The study of dynamic biological processes requires a microscope system with multiple modalities, high spatial/temporal resolution, large imaging ranges, versatile imaging environments and ideally in-situ manipulation capabilities. Recent development of new Atomic Force Microscopy (AFM) capabilities has made it such a powerful tool for biological and biomedical research. This review introduces novel AFM functionalities including high-speed imaging for dynamic process visualization, mechanobiology with force spectroscopy, molecular species characterization, and AFM nano-manipulation. These capabilities enable many new possibilities for novel scientific research and allow scientists to observe and explore processes at the nanoscale like never before. Selected application examples from recent studies are provided to demonstrate the effectiveness of these AFM techniques.

Style APA, Harvard, Vancouver, ISO itp.

5

Ignat, Ioan, Bernhard Schuster, Jonas Hafner, MinHee Kwon, Daniel Platz i Ulrich Schmid. "Intermodal coupling spectroscopy of mechanical modes in microcantilevers". Beilstein Journal of Nanotechnology 14 (19.01.2023): 123–32. http://dx.doi.org/10.3762/bjnano.14.13.

Pełny tekst źródła

Streszczenie:

Atomic force microscopy (AFM) is highly regarded as a lens peering into the next discoveries of nanotechnology. Fundamental research in atomic interactions, molecular reactions, and biological cell behaviour are key focal points, demanding a continuous increase in resolution and sensitivity. While renowned fields such as optomechanics have marched towards outstanding signal-to-noise ratios, these improvements have yet to find a practical way to AFM. As a solution, we investigate here a mechanism in which individual mechanical eigenmodes of a microcantilever couple to one another, mimicking optomechanical techniques to reduce thermal noise. We have a look at the most commonly used modes in AFM, starting with the first two flexural modes of cantilevers and asses the impact of an amplified coupling between them. In the following, we expand our investigation to the sea of eigenmodes available in the same structure and find a maximum coupling of 9.38 × 103 Hz/nm between two torsional modes. Through such findings we aim to expand the field of multifrequency AFM with innumerable possibilities leading to improved signal-to-noise ratios, all accessible with no additional hardware.

Style APA, Harvard, Vancouver, ISO itp.

6

Pishkenari, Hossein Nejat, i Ali Meghdari. "Effects of higher oscillation modes on TM-AFM measurements". Ultramicroscopy 111, nr 2 (styczeń 2011): 107–16. http://dx.doi.org/10.1016/j.ultramic.2010.10.015.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

7

Patel, Anisha N., i Christine Kranz. "(Multi)functional Atomic Force Microscopy Imaging". Annual Review of Analytical Chemistry 11, nr 1 (12.06.2018): 329–50. http://dx.doi.org/10.1146/annurev-anchem-061417-125716.

Pełny tekst źródła

Streszczenie:

Incorporating functionality to atomic force microscopy (AFM) to obtain physical and chemical information has always been a strong focus in AFM research. Modifying AFM probes with specific molecules permits accessibility of chemical information via specific reactions and interactions. Fundamental understanding of molecular processes at the solid/liquid interface with high spatial resolution is essential to many emerging research areas. Nanoscale electrochemical imaging has emerged as a complementary technique to advanced AFM techniques, providing information on electrochemical interfacial processes. While this review presents a brief introduction to advanced AFM imaging modes, such as multiparametric AFM and topography recognition imaging, the main focus herein is on electrochemical imaging via hybrid AFM-scanning electrochemical microscopy. Recent applications and the challenges associated with such nanoelectrochemical imaging strategies are presented.

Style APA, Harvard, Vancouver, ISO itp.

8

Li, Qing Fen, Li Zhu, Guo Jin i Xiu Fang Cui. "3D-Modeling and Numerical Analysis of Fracture Behavior in AFM-Specimen on Mixed-Mode I-II Loading Condition". Advanced Materials Research 450-451 (styczeń 2012): 1391–94. http://dx.doi.org/10.4028/www.scientific.net/amr.450-451.1391.

Pełny tekst źródła

Streszczenie:

The computational analysis of a three-dimensional (3D) finite element model of all fracture modes (AFM) specimen on mixed-mode I-II fracture was presented in this paper. The separated energy release rates (SERRs) along the crack front of the AFM-model were calculated by the modified virtual crack closure integral (MVCCI)-method and commercially available software ANSYS. The influence of finite geometry and loading angles on mixed mode I-II fracture was investigated.

Style APA, Harvard, Vancouver, ISO itp.

9

Guzman, Horacio V., Pablo D. Garcia i Ricardo Garcia. "Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments". Beilstein Journal of Nanotechnology 6 (4.02.2015): 369–79. http://dx.doi.org/10.3762/bjnano.6.36.

Pełny tekst źródła

Streszczenie:

We present a simulation environment, dForce, which can be used for a better understanding of dynamic force microscopy experiments. The simulator presents the cantilever–tip dynamics for two dynamic AFM methods, tapping mode AFM and bimodal AFM. It can be applied for a wide variety of experimental situations in air or liquid. The code provides all the variables and parameters relevant in those modes, for example, the instantaneous deflection and tip–surface force, velocity, virial, dissipated energy, sample deformation and peak force as a function of time or distance. The simulator includes a variety of interactions and contact mechanics models to describe AFM experiments including: van der Waals, Hertz, DMT, JKR, bottom effect cone correction, linear viscoelastic forces or the standard linear solid viscoelastic model. We have compared two numerical integration methods to select the one that offers optimal accuracy and speed. The graphical user interface has been designed to facilitate the navigation of non-experts in simulations. Finally, the accuracy of dForce has been tested against numerical simulations performed during the last 18 years.

Style APA, Harvard, Vancouver, ISO itp.

10

Starodubtseva, M. N. "Atomic force microscopy of cells as a method for the study of the pathogenesis and AS THE basis for the development of methods of DISEASE DIAGNOSIS". Health and Ecology Issues, nr 4 (28.12.2017): 99–106. http://dx.doi.org/10.51523/2708-6011.2017-14-4-21.

Pełny tekst źródła

Streszczenie:

The application of atomic force microscopy (AFM) for the study of micro- and nanoscale areas of the cell surface allows researchers to introduce new cell parameters and to obtain qualitatively new notions about the causes and mechanisms of changes of the cell properties. The aim of the work was to assess the prospects of AFM of cells using the example of blood cells for the study and development of new methods of disease diagnosis based on the specificity of AFM modes of operation and the recent AFM data on the cell surface properties.

Style APA, Harvard, Vancouver, ISO itp.

11

Tang, Deman, i Earl H. Dowell. "Reduced Order Model Analysis for Two-Dimensional Molecular Dynamic Chain Structure Attached to an Atomic Force Microscope". Journal of Dynamic Systems, Measurement, and Control 126, nr 3 (1.09.2004): 531–46. http://dx.doi.org/10.1115/1.1789969.

Pełny tekst źródła

Streszczenie:

Dynamic analysis and numerical simulation of a protein-ligand chain structure connected to a moving atomic force microscope (AFM) has been conducted. The elements of the chain are free to extend and rotate relative to each other in a two-dimensional plane. Sinusoidal base excitation of the cantilevered beam of the AFM is considered in some detail. Reduced order (dynamic) models are constructed using global modes for both linear and nonlinear dynamic systems with and without the “nearest neighbor assumption.” The agreement between the original and reduced order models (ROM) is very good even when only one global mode is included in the ROM for either the linear case or for the nonlinear case, provided the excitation frequency is lower than the fundamental natural frequency of the linear system. For higher excitation frequencies, more global modes are required. The computational advantage of the reduced order model is clear from the results presented.

Style APA, Harvard, Vancouver, ISO itp.

12

Blinov, Iliya V., Tatiana P. Krinitsina, Mikhail A. Milyaev, Vladimir V. Popov i Vladimir V. Ustinov. "Unidirectional Anisotropy in Nanostructures with Antiferromagnetic NiFeMn Layer". Solid State Phenomena 233-234 (lipiec 2015): 517–21. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.517.

Pełny tekst źródła

Streszczenie:

Magnetic properties of nanostructures including an antiferromagnetic (NiFe)1-хMnx alloy have been studied for various modes of this AFM layer preparation. The possibility for application of the AFM (NiFe)1-хMnx alloy as a material of the pinning layer in spin valves is discussed.

Style APA, Harvard, Vancouver, ISO itp.

13

Woodward, John T. "Choosing a Cantilever for In Situ Atomic Force Microscopy". Microscopy Today 11, nr 2 (kwiecień 2003): 42–43. http://dx.doi.org/10.1017/s1551929500052500.

Pełny tekst źródła

Streszczenie:

What is the best cantilever for intermittent contact mode (often called Tapping Mode™) atomic force microscope (AFM) imaging under water? This is a question I hear often and one that recently generated some interesting discussion on an AFM newsgroup (more on the newsgroup below). The ability of the AFM to image samples En physiologically relevant environments has made it a popular technique in the biological sciences. However, because scanning the AFM tip in contact mode easily perturbs many biological samples, it was the advent of intermittent contact modes that lead to AFM's widespread use in biology.

Style APA, Harvard, Vancouver, ISO itp.

14

Seewald, Lukas Matthias, Jürgen Sattelkow, Michele Brugger-Hatzl, Gerald Kothleitner, Hajo Frerichs, Christian Schwalb, Stefan Hummel i Harald Plank. "3D Nanoprinting of All-Metal Nanoprobes for Electric AFM Modes". Nanomaterials 12, nr 24 (17.12.2022): 4477. http://dx.doi.org/10.3390/nano12244477.

Pełny tekst źródła

Streszczenie:

3D nanoprinting via focused electron beam induced deposition (FEBID) is applied for fabrication of all-metal nanoprobes for atomic force microscopy (AFM)-based electrical operation modes. The 3D tip concept is based on a hollow-cone (HC) design, with all-metal material properties and apex radii in the sub-10 nm regime to allow for high-resolution imaging during morphological imaging, conductive AFM (CAFM) and electrostatic force microscopy (EFM). The study starts with design aspects to motivate the proposed HC architecture, followed by detailed fabrication characterization to identify and optimize FEBID process parameters. To arrive at desired material properties, e-beam assisted purification in low-pressure water atmospheres was applied at room temperature, which enabled the removal of carbon impurities from as-deposited structures. The microstructure of final HCs was analyzed via scanning transmission electron microscopy—high-angle annular dark field (STEM-HAADF), whereas electrical and mechanical properties were investigated in situ using micromanipulators. Finally, AFM/EFM/CAFM measurements were performed in comparison to non-functional, high-resolution tips and commercially available electric probes. In essence, we demonstrate that the proposed all-metal HCs provide the resolution capabilities of the former, with the electric conductivity of the latter onboard, combining both assets in one design.

Style APA, Harvard, Vancouver, ISO itp.

15

Moore, Steven Ian, Michael G. Ruppert i Yuen Kuan Yong. "Multimodal cantilevers with novel piezoelectric layer topology for sensitivity enhancement". Beilstein Journal of Nanotechnology 8 (6.02.2017): 358–71. http://dx.doi.org/10.3762/bjnano.8.38.

Pełny tekst źródła

Streszczenie:

Self-sensing techniques for atomic force microscope (AFM) cantilevers have several advantageous characteristics compared to the optical beam deflection method. The possibility of down scaling, parallelization of cantilever arrays and the absence of optical interference associated imaging artifacts have led to an increased research interest in these methods. However, for multifrequency AFM, the optimization of the transducer layout on the cantilever for higher order modes has not been addressed. To fully utilize an integrated piezoelectric transducer, this work alters the layout of the piezoelectric layer to maximize both the deflection of the cantilever and measured piezoelectric charge response for a given mode with respect to the spatial distribution of the strain. On a prototype cantilever design, significant increases in actuator and sensor sensitivities were achieved for the first four modes without any substantial increase in sensor noise. The transduction mechanism is specifically targeted at multifrequency AFM and has the potential to provide higher resolution imaging on higher order modes.

Style APA, Harvard, Vancouver, ISO itp.

16

Russell, Phillip E., i A. D. Batchelor. "AFM and Other Scanned Probe Microscopies Tutorial". Microscopy and Microanalysis 4, S2 (lipiec 1998): 878–79. http://dx.doi.org/10.1017/s143192760002451x.

Pełny tekst źródła

Streszczenie:

While the techniques offer high spatial resolution in some cases down to the atomic scale and three dimensional mapping of surface topography, there still remain issues related to quantitative interpretation of scanned probe data, particularly in the recently developed phase contrast imaging modes. In this talk, the various modes of force microscopy will be introduced, along with examples. New techniques are starting to emerge which allow us to use the scanned probe microscope to measure properties such as local adhesion and local elastic and plastic deformation of samples.Each scanned probe technique relies on a very sharp probe positioned within a few nanometers of the surface of interest. Some combination of probe and/or substrate positioning is required to provide sub-nm-resolution, three-dimensional motion of the probe relative to the substrate. When the probe translates laterally (horizontally) relative to the sample, any change in the height of the surface causes the detected probe signal to change.

Style APA, Harvard, Vancouver, ISO itp.

17

Ulcinas, Arturas, i Valentinas Snitka. "Intermittent contact AFM using the higher modes of weak cantilever". Ultramicroscopy 86, nr 1-2 (styczeń 2001): 217–22. http://dx.doi.org/10.1016/s0304-3991(00)00084-x.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

18

Ho, Huddee J. "Near Contact Mode AFM: Overcoming Surface Fluid Layer In Air And Achieve Ultra-High Resolution". Microscopy Today 6, nr 8 (październik 1998): 12–15. http://dx.doi.org/10.1017/s1551929500069170.

Pełny tekst źródła

Streszczenie:

A major goal of Atomic Force Microscopy (AFM) is to achieve nanometer resolution on surface topography, Vibrating cantilever mode (VCM) is an important configuration of an AFU instrument, It was proposed in the first AFM paper.VCM in ultra-high vacuum (UHV) results in true AFM atomic resolution, which reveals atomic scale surface defects such as a single missing atom in a lattice. However, the VCM operation in air has many difficulties due to the surface contamination on the sample and the AFM tip. The most popular operation modes of the VCM are the non-contact mode and the Tapping mode. Both of these have limited lateral resolution in air.

Style APA, Harvard, Vancouver, ISO itp.

19

Slattery, Ashley, Cameron Shearer, Joseph Shapter, Adam Blanch, Jamie Quinton i Christopher Gibson. "Improved Application of Carbon Nanotube Atomic Force Microscopy Probes Using PeakForce Tapping Mode". Nanomaterials 8, nr 10 (9.10.2018): 807. http://dx.doi.org/10.3390/nano8100807.

Pełny tekst źródła

Streszczenie:

In this work PeakForce tapping (PFT) imaging was demonstrated with carbon nanotube atomic force microscopy (CNT-AFM) probes; this imaging mode shows great promise for providing simple, stable imaging with CNT-AFM probes, which can be difficult to apply. The PFT mode is used with CNT-AFM probes to demonstrate high resolution imaging on samples with features in the nanometre range, including a Nioprobe calibration sample and gold nanoparticles on silicon, in order to demonstrate the modes imaging effectiveness, and to also aid in determining the diameter of very thin CNT-AFM probes. In addition to stable operation, the PFT mode is shown to eliminate “ringing” artefacts that often affect CNT-AFM probes in tapping mode near steep vertical step edges. This will allow for the characterization of high aspect ratio structures using CNT-AFM probes, an exercise which has previously been challenging with the standard tapping mode.

Style APA, Harvard, Vancouver, ISO itp.

20

Marcuello, Carlos. "Current and future perspectives of atomic force microscopy to elicit the intrinsic properties of soft matter at the single molecule level". AIMS Bioengineering 9, nr 3 (2022): 293–306. http://dx.doi.org/10.3934/bioeng.2022020.

Pełny tekst źródła

Streszczenie:

<abstract> <p>Soft matter encompasses multitude of systems like biomolecules, living cells, polymers, composites or blends. The increasing interest to better understand their physico-chemical properties has significantly favored the development of new techniques with unprecedented resolution. In this framework, atomic force microscopy (AFM) can act as one main actor to address multitude of intrinsic sample characteristics at the nanoscale level. AFM presents many advantages in comparison to other bulk techniques as the assessment of individual entities discharging thus, ensemble averaging phenomena. Moreover, AFM enables the visualization of singular events that eventually can provide response of some open questions that still remain unclear. The present manuscript aims to make the reader aware of the potential applications in the employment of this tool by providing recent examples of scientific studies where AFM has been employed with success. Several operational modes like AFM imaging, AFM based force spectroscopy (AFM-FS), nanoindentation, AFM-nanoscale infrared spectroscopy (AFM-nanoIR) or magnetic force microscopy (MFM) will be fully explained to detail the type of information that AFM is capable to gather. Finally, future prospects will be delivered to discern the following steps to be conducted in this field.</p> </abstract>

Style APA, Harvard, Vancouver, ISO itp.

21

Zhang, Suoxin, Jianqiang Qian, Yingzi Li, Yingxu Zhang i Zhenyu Wang. "A Novel Method to Reconstruct the Force Curve by Higher Harmonics of the First Two Flexural Modes in Frequency Modulation Atomic Force Microscope (FM-AFM)". Microscopy and Microanalysis 24, nr 3 (czerwiec 2018): 256–63. http://dx.doi.org/10.1017/s1431927618000363.

Pełny tekst źródła

Streszczenie:

AbstractAtomic force microscope (AFM) is an idealized tool to measure the physical and chemical properties of the sample surfaces by reconstructing the force curve, which is of great significance to materials science, biology, and medicine science. Frequency modulation atomic force microscope (FM-AFM) collects the frequency shift as feedback thus having high force sensitivity and it accomplishes a true noncontact mode, which means great potential in biological sample detection field. However, it is a challenge to establish the relationship between the cantilever properties observed in practice and the tip–sample interaction theoretically. Moreover, there is no existing method to reconstruct the force curve in FM-AFM combining the higher harmonics and the higher flexural modes. This paper proposes a novel method that a full force curve can be reconstructed by any order higher harmonics of the first two flexural modes under any vibration amplitude in FM-AFM. Moreover, in the small amplitude regime, short range forces are reconstructed more accurately by higher harmonics analysis compared with fundamental harmonics using the Sader–Jarvis formula.

Style APA, Harvard, Vancouver, ISO itp.

22

Boisgard, R., J. P. Aimé i G. Couturier. "Dynamic operation modes of AFM: Non-linear behavior and theoretical analysis of the stability of the AFM oscillator". International Journal of Non-Linear Mechanics 42, nr 4 (maj 2007): 673–80. http://dx.doi.org/10.1016/j.ijnonlinmec.2007.03.006.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

23

Kalafut, Devin, Ryan Wagner, Maria Jose Cadena, Anil Bajaj i Arvind Raman. "Cantilever signature of tip detachment during contact resonance AFM". Beilstein Journal of Nanotechnology 12 (24.11.2021): 1286–96. http://dx.doi.org/10.3762/bjnano.12.96.

Pełny tekst źródła

Streszczenie:

Contact resonance atomic force microscopy, piezoresponse force microscopy, and electrochemical strain microscopy are atomic force microscopy modes in which the cantilever is held in contact with the sample at a constant average force while monitoring the cantilever motion under the influence of a small, superimposed vibrational signal. Though these modes depend on permanent contact, there is a lack of detailed analysis on how the cantilever motion evolves when this essential condition is violated. This is not an uncommon occurrence since higher operating amplitudes tend to yield better signal-to-noise ratio, so users may inadvertently reduce their experimental accuracy by inducing tip–sample detachment in an effort to improve their measurements. We shed light on this issue by deliberately pushing both our experimental equipment and numerical simulations to the point of tip–sample detachment to explore cantilever dynamics during a useful and observable threshold feature in the measured response. Numerical simulations of the analytical model allow for extended insight into cantilever dynamics such as full-length deflection and slope behavior, which can be challenging or unobtainable in a standard equipment configuration. With such tools, we are able to determine the cantilever motion during detachment and connect the qualitative and quantitative behavior to experimental features.

Style APA, Harvard, Vancouver, ISO itp.

24

Mišić Radić, Tea, Petra Vukosav, Andrea Čačković i Alexander Dulebo. "Insights into the Morphology and Surface Properties of Microalgae at the Nanoscale by Atomic Force Microscopy (AFM): A Review". Water 15, nr 11 (23.05.2023): 1983. http://dx.doi.org/10.3390/w15111983.

Pełny tekst źródła

Streszczenie:

Atomic force microscopy (AFM) is a method that provides the nanometer-resolution three-dimensional imaging of living cells in their native state in their natural physiological environment. In addition, AFM’s sensitivity to measure interaction forces in the piconewton range enables researchers to probe surface properties, such as elasticity, viscoelasticity, hydrophobicity and adhesion. Despite the growing number of applications of AFM as a method to study biological systems, AFM is not yet an established technique for studying microalgae. Following a brief introduction to the basic principles and operation modes of AFM, this review highlights the major contributions of AFM in the field of microalgae research. A pioneering AFM study on microalgae was performed on diatoms, revealing the fine structural details of diatom frustule, without the need for sample modification. While, to date, diatoms are the most studied class of microalgae using AFM, it has also been used to study microalgae belonging to other classes. Besides using AFM for the morphological characterization of microalgae at the single cell level, AFM has also been used to study the surface properties of microalgal cells, with cell elasticity being most frequently studied one. Here, we also present our preliminary results on the viscoelastic properties of microalgae cell (Dunaliella tertiolecta), as the first microrheological study of microalgae. Overall, the studies presented show that AFM, with its multiparametric characterization, alone or in combination with other complementary techniques, can address many outstanding questions in the field of microalgae.

Style APA, Harvard, Vancouver, ISO itp.

25

Zhang, Rui, Evgeny Zhuravlev, René Androsch i Christoph Schick. "Visualization of Polymer Crystallization by In Situ Combination of Atomic Force Microscopy and Fast Scanning Calorimetry". Polymers 11, nr 5 (15.05.2019): 890. http://dx.doi.org/10.3390/polym11050890.

Pełny tekst źródła

Streszczenie:

A chip-based fast scanning calorimeter (FSC) is used as a fast hot-stage in an atomic force microscope (AFM). This way, the morphology of materials with a resolution from micrometers to nanometers after fast thermal treatments becomes accessible. An FSC can treat the sample isothermally or at heating and cooling rates up to 1 MK/s. The short response time of the FSC in the order of milliseconds enables rapid changes from scanning to isothermal modes and vice versa. Additionally, FSC provides crystallization/melting curves of the sample just imaged by AFM. We describe a combined AFM-FSC device, where the AFM sample holder is replaced by the FSC chip-sensor. The sample can be repeatedly annealed at pre-defined temperatures and times and the AFM images can be taken from exactly the same spot of the sample. The AFM-FSC combination is used for the investigation of crystallization of polyamide 66 (PA 66), poly(ether ether ketone) (PEEK), poly(butylene terephthalate) (PBT) and poly(ε-caprolactone) (PCL).

Style APA, Harvard, Vancouver, ISO itp.

26

Casuso, Ignacio, Lorena Redondo-Morata i Felix Rico. "Biological physics by high-speed atomic force microscopy". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, nr 2186 (26.10.2020): 20190604. http://dx.doi.org/10.1098/rsta.2019.0604.

Pełny tekst źródła

Streszczenie:

While many fields have contributed to biological physics, nanotechnology offers a new scale of observation. High-speed atomic force microscopy (HS-AFM) provides nanometre structural information and dynamics with subsecond resolution of biological systems. Moreover, HS-AFM allows us to measure piconewton forces within microseconds giving access to unexplored, fast biophysical processes. Thus, HS-AFM provides a tool to nourish biological physics through the observation of emergent physical phenomena in biological systems. In this review, we present an overview of the contribution of HS-AFM, both in imaging and force spectroscopy modes, to the field of biological physics. We focus on examples in which HS-AFM observations on membrane remodelling, molecular motors or the unfolding of proteins have stimulated the development of novel theories or the emergence of new concepts. We finally provide expected applications and developments of HS-AFM that we believe will continue contributing to our understanding of nature, by serving to the dialogue between biology and physics. This article is part of a discussion meeting issue ‘Dynamic in situ microscopy relating structure and function’.

Style APA, Harvard, Vancouver, ISO itp.

27

Meier, Dale J. "Application of various modes of scanning-probe microscopies in polymer systems". Proceedings, annual meeting, Electron Microscopy Society of America 54 (11.08.1996): 196–97. http://dx.doi.org/10.1017/s0424820100163447.

Pełny tekst źródła

Streszczenie:

The invention of the scanning tunneling microscope (STM) by Binnig and Rohrer in 1982 demonstrated an unparalleled ability to image materials at the sub-nanometer scale. The invention rapidly lead to an explosion of applications of STM in a wide variety of fields. However, imaging by an STM is essentially limited to materials which are conductive, or could be made conductive, so many materials of interest could not be imaged by STM. This limitation was removed a few years later (1985) by the invention of the atomic force microscope (AFM) by Binnig, Quate and Gerber, in which imaging is based on the response of a soft cantilever beam to the contact forces between an ultra-fine probe tip and a sample. The cantilever/probe systems could be made sensitive enough to enable the AFM to easily resolve atomic or molecular level features.

Style APA, Harvard, Vancouver, ISO itp.

28

Chen, Ying, Ke Ma, Ting Hu, Bo Jiang, Bin Xu, Wenjing Tian, Jing Zhi Sun i Wenke Zhang. "Investigation of the binding modes between AIE-active molecules and dsDNA by single molecule force spectroscopy". Nanoscale 7, nr 19 (2015): 8939–45. http://dx.doi.org/10.1039/c5nr01247c.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

29

Gibson, Christopher T. "The Attachment of Carbon Nanotubes to Atomic Force Microscopy Tips Using the Pick-Up Method". Applied Sciences 10, nr 16 (12.08.2020): 5575. http://dx.doi.org/10.3390/app10165575.

Pełny tekst źródła

Streszczenie:

In the last 30 years research has shown that the resolution and reproducibility of data acquired using the atomic force microscope (AFM) can be improved through the development of new imaging modes or by modifying the AFM tip. One method that has been explored since the 1990s is to attach carbon nanotubes (CNT) to AFM tips. CNTs possess a small diameter, high aspect ratio, high strength and demonstrate a high degree of wear resistance. While early indications suggested the widespread use of these types of probes would be routine this has not been the case. A number of methods for CNT attachment have been proposed and explored including chemical vapor deposition (CVD), dielectrophoresis and manual attachment inside a scanning electron microscope (SEM). One of the earliest techniques developed is known as the pick-up method and involves adhering CNTs to AFM tips by simply scanning the AFM tip, in tapping mode, across a CNT-covered surface until a CNT attaches to the AFM tip. In this work we will further investigate how, for example, high force tapping mode imaging can improve the stability and success rate of the pick-up method. We will also discuss methods to determine CNT attachment to AFM probes including changes in AFM image resolution, amplitude versus distance curves and SEM imaging. We demonstrate that the pick-up method can be applied to a range of AFM probes, including contact mode probes with relatively soft spring constants (0.28 N/m). Finally, we demonstrate that the pick-up method can be used to attach CNTs to two AFM tips simultaneously. This is significant as it demonstrates the techniques potential for attaching CNTs to multiple AFM tips which could have applications in AFM-based data storage, devices such as the Snomipede, or making CNT-AFM tips more commercially viable.

Style APA, Harvard, Vancouver, ISO itp.

30

Damircheli, Mehrnoosh, Amir F. Payam i Ricardo Garcia. "Optimization of phase contrast in bimodal amplitude modulation AFM". Beilstein Journal of Nanotechnology 6 (28.04.2015): 1072–81. http://dx.doi.org/10.3762/bjnano.6.108.

Pełny tekst źródła

Streszczenie:

Bimodal force microscopy has expanded the capabilities of atomic force microscopy (AFM) by providing high spatial resolution images, compositional contrast and quantitative mapping of material properties without compromising the data acquisition speed. In the first bimodal AFM configuration, an amplitude feedback loop keeps constant the amplitude of the first mode while the observables of the second mode have not feedback restrictions (bimodal AM). Here we study the conditions to enhance the compositional contrast in bimodal AM while imaging heterogeneous materials. The contrast has a maximum by decreasing the amplitude of the second mode. We demonstrate that the roles of the excited modes are asymmetric. The operational range of bimodal AM is maximized when the second mode is free to follow changes in the force. We also study the contrast in trimodal AFM by analyzing the kinetic energy ratios. The phase contrast improves by decreasing the energy of second mode relative to those of the first and third modes.

Style APA, Harvard, Vancouver, ISO itp.

31

Killgore, Jason P., William King, Kevin Kjoller i René M. Overney. "Heated-Tip AFM: Applications in Nanocomposite Polymer Membranes and Energetic Materials". Microscopy Today 15, nr 1 (styczeń 2007): 20–25. http://dx.doi.org/10.1017/s1551929500051142.

Pełny tekst źródła

Streszczenie:

Atomic Force Microscopy (AFM) is a key technique for the measurement and analysis of samples when nanoscale topography is of interest. It offers a number of complementary probing modes that extend an AFM's measurement capability to a wide range of material and transport properties of surfaces, including hardness, friction, conductivity and adhesion among others. Sample temperature controlled AFM extends the study of surface morphology and properties to include changes in the material phases.Recently, silicon microfabricated AFM cantilevers that have integrated heaters, as shown in figure 1, have become commercially available. These cantilevers were initially developed for probe based data storage by researchers at IBM Zurich, Figure 1. With the availability of these cantilevers, AFM measurements can be performed where the tip is heated as opposed to the sample.

Style APA, Harvard, Vancouver, ISO itp.

32

Surtchev, Marko, Mark Wall i Sergei Magonov. "Combined AFM/Raman Studies of Heterogeneous Polymer Materials". MRS Advances 1, nr 25 (2016): 1859–64. http://dx.doi.org/10.1557/adv.2016.412.

Pełny tekst źródła

Streszczenie:

ABSTRACTCompositional imaging of several immiscible polymer blends was examined with the combination of AFM-based mechanical and electric modes with chemically-specific Raman mapping. Results showed that these methods substantially complement each other in comprehensive characterization of surface morphology by helping to identify a composition of top surface and sub-surface materials in polymer heterogeneous systems.

Style APA, Harvard, Vancouver, ISO itp.

33

Stylianou, Andreas, Stylianos-Vasileios Kontomaris, Colin Grant i Eleni Alexandratou. "Atomic Force Microscopy on Biological Materials Related to Pathological Conditions". Scanning 2019 (12.05.2019): 1–25. http://dx.doi.org/10.1155/2019/8452851.

Pełny tekst źródła

Streszczenie:

Atomic force microscopy (AFM) is an easy-to-use, powerful, high-resolution microscope that allows the user to image any surface and under any aqueous condition. AFM has been used in the investigation of the structural and mechanical properties of a wide range of biological matters including biomolecules, biomaterials, cells, and tissues. It provides the capacity to acquire high-resolution images of biosamples at the nanoscale and allows at readily carrying out mechanical characterization. The capacity of AFM to image and interact with surfaces, under physiologically relevant conditions, is of great importance for realistic and accurate medical and pharmaceutical applications. The aim of this paper is to review recent trends of the use of AFM on biological materials related to health and sickness. First, we present AFM components and its different imaging modes and we continue with combined imaging and coupled AFM systems. Then, we discuss the use of AFM to nanocharacterize collagen, the major fibrous protein of the human body, which has been correlated with many pathological conditions. In the next section, AFM nanolevel surface characterization as a tool to detect possible pathological conditions such as osteoarthritis and cancer is presented. Finally, we demonstrate the use of AFM for studying other pathological conditions, such as Alzheimer’s disease and human immunodeficiency virus (HIV), through the investigation of amyloid fibrils and viruses, respectively. Consequently, AFM stands out as the ideal research instrument for exploring the detection of pathological conditions even at very early stages, making it very attractive in the area of bio- and nanomedicine.

Style APA, Harvard, Vancouver, ISO itp.

34

Liu, Hao, Zuned Ahmed, Sasa Vranjkovic, Manfred Parschau, Andrada-Oana Mandru i Hans J. Hug. "A cantilever-based, ultrahigh-vacuum, low-temperature scanning probe instrument for multidimensional scanning force microscopy". Beilstein Journal of Nanotechnology 13 (11.10.2022): 1120–40. http://dx.doi.org/10.3762/bjnano.13.95.

Pełny tekst źródła

Streszczenie:

Cantilever-based atomic force microscopy (AFM) performed under ambient conditions has become an important tool to characterize new material systems as well as devices. Current instruments permit robust scanning over large areas, atomic-scale lateral resolution, and the characterization of various sample properties using multifrequency and multimodal AFM operation modes. Research of new quantum materials and devices, however, often requires low temperatures and ultrahigh vacuum (UHV) conditions and, more specifically, AFM instrumentation providing atomic resolution. For this, AFM instrumentation based on a tuning fork force sensor became increasingly popular. In comparison to microfabricated cantilevers, the more macroscopic tuning forks, however, lack sensitivity, which limits the measurement bandwidth. Moreover, multimodal and multifrequency techniques, such as those available in cantilever-based AFM carried out under ambient conditions, are challenging to implement. In this article, we describe a cantilever-based low-temperature UHV AFM setup that allows one to transfer the versatile AFM techniques developed for ambient conditions to UHV and low-temperature conditions. We demonstrate that such a cantilever-based AFM offers experimental flexibility by permitting multimodal or multifrequency operations with superior force derivative sensitivities and bandwidths. Our instrument has a sub-picometer gap stability and can simultaneously map not only vertical and lateral forces with atomic-scale resolution, but also perform rapid overview scans with the tip kept at larger tip–sample distances for robust imaging.

Style APA, Harvard, Vancouver, ISO itp.

35

Williams, R. E. "Acoustic Emission Characteristics of Abrasive Flow Machining". Journal of Manufacturing Science and Engineering 120, nr 2 (1.05.1998): 264–71. http://dx.doi.org/10.1115/1.2830123.

Pełny tekst źródła

Streszczenie:

Abrasive Flow Machining (AFM) is a nontraditional finishing process that deburrs and polishes by forcing an abrasive-laden viscoelastic polymer across the workpiece surface. Current applications include improvement in air and fluid flow for cylinder heads, intake manifold runners and injector nozzles. Present manufacturing methods include a series of flow test and AFM operations which require significant material handling and operator adjustment. An effective on-line monitoring and adaptive control system for AFM is needed. This paper reports on the development of an acoustic emission (AE) based monitoring strategy and the AE characteristics of abrasive flow machining. Initial results showed AE to be a viable sensing method for determining the performance characteristics of AFM for simple extrusion passage geometries in a selected part design. The root mean square (RMS) voltage of the AE signal was mainly determined by the metal removal and related AFM process parameters. Frequency decomposition of the AE signals revealed distinct frequency bands which have been related to the different material removal modes in AFM and to the workpiece material. Research was also performed on the application of AFM to finish orifices of varying sizes. Extremely high correlations were found between the AE signal and both the orifice diameter and the volumetric flow rate. Work is continuing with the equipment manufacturer and key industrial users to apply the monitoring strategy as part of a prototype Flow Control AFM.

Style APA, Harvard, Vancouver, ISO itp.

36

Villeneuve-Faure, Christina, Abdelhaq Boumaarouf, Vishal Shah, Peter M. Gammon, Ulrike Lüders i Rosine Coq Germanicus. "SiC Doping Impact during Conducting AFM under Ambient Atmosphere". Materials 16, nr 15 (1.08.2023): 5401. http://dx.doi.org/10.3390/ma16155401.

Pełny tekst źródła

Streszczenie:

The characterization of silicon carbide (SiC) by specific electrical atomic force microscopy (AFM) modes is highly appreciated for revealing its structure and properties at a nanoscale. However, during the conductive AFM (C-AFM) measurements, the strong electric field that builds up around and below the AFM conductive tip in ambient atmosphere may lead to a direct anodic oxidation of the SiC surface due to the formation of a water nanomeniscus. In this paper, the underlying effects of the anodization are experimentally investigated for SiC multilayers with different doping levels by studying gradual SiC epitaxial-doped layers with nitrogen (N) from 5 × 1017 to 1019 at/cm3. The presence of the water nanomeniscus is probed by the AFM and analyzed with the force–distance curve when a negative bias is applied to the AFM tip. From the water meniscus breakup distance measured without and with polarization, the water meniscus volume is increased by a factor of three under polarization. AFM experimental results are supported by electrostatic modeling to study oxide growth. By taking into account the presence of the water nanomeniscus, the surface oxide layer and the SiC doping level, a 2D-axisymmetric finite element model is developed to calculate the electric field distribution nearby the tip contact and the current distributions at the nanocontact. The results demonstrate that the anodization occurred for the conductive regime in which the current depends strongly to the doping; its threshold value is 7 × 1018 at/cm3 for anodization. Finally, the characterization of a classical planar SiC-MOSFET by C-AFM is examined. Results reveal the local oxidation mechanism of the SiC material at the surface of the MOSFET structure. AFM topographies after successive C-AFM measurements show that the local oxide created by anodization is located on both sides of the MOS channel; these areas are the locations of the highly n-type-doped zones. A selective wet chemical etching confirms that the oxide induced by local anodic oxidation is a SiOCH layer.

Style APA, Harvard, Vancouver, ISO itp.

37

Ouyang, Qijian, Zhiwei Xie, Jinhai Liu, Minghui Gong i Huayang Yu. "Application of Atomic Force Microscopy as Advanced Asphalt Testing Technology: A Comprehensive Review". Polymers 14, nr 14 (13.07.2022): 2851. http://dx.doi.org/10.3390/polym14142851.

Pełny tekst źródła

Streszczenie:

In the past three decades, researchers have engaged in the relationship between the composition, macro performance, and microstructure of asphalt. There are many research results in the use of atomic force microscopy (AFM) to study the microstructure and related mechanisms of asphalt. Based on previous studies, the performance of asphalt from its microstructure has been observed and analyzed, and different evaluation indices and modification methods have been proposed, providing guidance toward improving the performance of asphalt materials and benefiting potential applications. This review focuses on the typical application and analysis of AFM in the study of the aging regeneration and modification properties of asphalt. Additionally, this review introduces the history of the rheological and chemical testing of asphalt materials and the history of using AFM to investigate asphalt. Furthermore, this review introduces the basic principles of various modes of application of AFM in the microstructure of asphalt, providing a research direction for the further popularization and application of AFM in asphalt or other materials in the future. This review aims to provide a reference and direction for researchers to further popularize the application of AFM in asphalt and standardize the testing methods of AFM. This paper is also helpful in further exploring the relationship between the microstructure and macro performance of asphalt.

Style APA, Harvard, Vancouver, ISO itp.

38

Carmichael, Stephen W., i Julio M. Fernandez. "Unzipping a Membrane". Microscopy Today 8, nr 9 (listopad 2000): 3–7. http://dx.doi.org/10.1017/s1551929500059368.

Pełny tekst źródła

Streszczenie:

The atomic force microscope (AFM) is well known for its outstanding spatial resolution, but it is becoming increasingly useful as the instrument for force spectroscopy. In the force spectroscopy mode, the AFM can measure tiny tension forces, in the piconewton (pN) range. Daniel Müller, Wolfgang Baurmeister, and Andreas Engel have used the AFM in both the imaging and force spectroscopy modes to pull proteins out of membranes in a controlled fashion.Müller et al. used Deinococcus radiodurans, a bacterium best known for its high resistance to radiation (as its Genus name implies), as their test subject. They extracted a highly regular membrane from the bacterium, the hexagonally packed intermediate (HPl) layer. They mounted the HPI on mica, so that the hydrophilic outer surface of the HPI adsorbed strongly to the mica, exposing the hydrophobic inner surface to the silicon nitride AFM stylus.

Style APA, Harvard, Vancouver, ISO itp.

39

Abbasi, Mohammad, i Seyed E. Afkhami. "Resonant Frequency and Sensitivity of a Caliper Formed With Assembled Cantilever Probes Based on the Modified Strain Gradient Theory". Microscopy and Microanalysis 20, nr 6 (10.09.2014): 1672–81. http://dx.doi.org/10.1017/s1431927614013117.

Pełny tekst źródła

Streszczenie:

AbstractThe resonant frequency and sensitivity of an atomic force microscope (AFM) with an assembled cantilever probe (ACP) is analyzed utilizing strain gradient theory, and then the governing equation and boundary conditions are derived by a combination of the basic equations of strain gradient theory and Hamilton’s principle. The resonant frequency and sensitivity of the proposed AFM microcantilever are then obtained numerically. The proposed ACP includes a horizontal cantilever, two vertical extensions, and two tips located at the free ends of the extensions that form a caliper. As one of the extensions is located between the clamped and free ends of the AFM microcantilever, the cantilever is modeled as two beams. The results of the current model are compared with those evaluated by both modified couple stress and classical beam theories. The difference in results evaluated by the strain gradient theory and those predicted by the couple stress and classical beam theories is significant, especially when the microcantilever thickness is approximately the same as the material length-scale parameters. The results also indicate that at the low values of contact stiffness, scanning in the higher cantilever modes decrease the accuracy of the proposed AFM ACP.

Style APA, Harvard, Vancouver, ISO itp.

40

Castanié, Fabien, Laurent Nony, Sébastien Gauthier i Xavier Bouju. "Graphite, graphene on SiC, and graphene nanoribbons: Calculated images with a numerical FM-AFM". Beilstein Journal of Nanotechnology 3 (2.04.2012): 301–11. http://dx.doi.org/10.3762/bjnano.3.34.

Pełny tekst źródła

Streszczenie:

Background: Characterization at the atomic scale is becoming an achievable task for FM-AFM users equipped, for example, with a qPlus sensor. Nevertheless, calculations are necessary to fully interpret experimental images in some specific cases. In this context, we developed a numerical AFM (n-AFM) able to be used in different modes and under different usage conditions. Results: Here, we tackled FM-AFM image calculations of three types of graphitic structures, namely a graphite surface, a graphene sheet on a silicon carbide substrate with a Si-terminated surface, and finally, a graphene nanoribbon. We compared static structures, meaning that all the tip and sample atoms are kept frozen in their equilibrium position, with dynamic systems, obtained with a molecular dynamics module allowing all the atoms to move freely during the probe oscillations. Conclusion: We found a very good agreement with experimental graphite and graphene images. The imaging process for the deposited nanoribbon demonstrates the stability of our n-AFM to image a non-perfectly planar substrate exhibiting a geometrical step as well as a material step.

Style APA, Harvard, Vancouver, ISO itp.

41

Li, Qing Fen, Li Zhu, Sheng Yuan Yan i Xiao Nan Zhang. "Computational Analysis of the AFM Specimen on Mixed-Mode I+II+III Fracture". Key Engineering Materials 488-489 (wrzesień 2011): 258–61. http://dx.doi.org/10.4028/www.scientific.net/kem.488-489.258.

Pełny tekst źródła

Streszczenie:

The computational analysis of an all fracture modes (AFM) specimen on mixed-mode I+II+III fracture is presented in this paper. The separated energy release rates (SERRs) along the crack front of the AFM-model are calculated by the modified virtual crack closure integral (MVCCI)-method and the commercially available software ANSYS. A transition model is built by adopting several 3D elements of SOLID45 and one point element of MASS21 in the ANSYS program. Under the related constraint conditions, the separate force and moments are respectively applied on the point element of the transition model, so the corresponding desired reaction forces can be obtained. When the desired loads are superimposed and applied on the AFM-model, the mixed-mode I+II+III fracture can then be achieved. Thereby, the SERR results are calculated. The calculation results show that the facture behavior of GII and GIII appears complex due to the global deformation and Poisson’s ratio, although the distribution of SEERs GI is symmetrical with respect to the middle point along the crack front. The total SERRs, GTn-values increase along the crack front with the minim value at one corner and the maxim value at the other corner. It can therefore be predicted that the fracture will occur initially at one corner on the crack front of the AFM-specimen in this case.

Style APA, Harvard, Vancouver, ISO itp.

42

Kheirodin, Mohsen, Hossein Nejat Pishkenari, Ali Moosavi i Ali Meghdari. "Study of Biomolecules Imaging Using Molecular Dynamics Simulations". Nano 10, nr 07 (październik 2015): 1550096. http://dx.doi.org/10.1142/s1793292015500964.

Pełny tekst źródła

Streszczenie:

The process of imaging a biomolecule by atomic force microscope (AFM) is modeled using molecular dynamics (MD) simulations. Since the large normal force exerted by the tip on the biosample in contact and tapping modes may damage the sample structure and produce irreversible deformation, the noncontact mode of AFM (NC-AFM) is employed as the operating mode. The biosample is scanned using a carbon nanotube (CNT) as the AFM probe. CNTs because of their small diameter, high aspect ratio and high mechanical resistance attract many attentions for imaging purposes. The tip–sample interaction is simulated by the MD method. The protein, which has been considered as the biomolecule, is ubiquitin and a graphene sheet is used as the substrate. The effects of CNT's geometric parameters such as the CNT height, the diameter, the tilt angle, the flexibility and the number of layers on the image quality have been evaluated.

Style APA, Harvard, Vancouver, ISO itp.

43

Coq Germanicus, R., i U. Lüders. "Electrical Characterizations Based on AFM: SCM and SSRM Measurements with a Multidimensional Approach". EDFA Technical Articles 24, nr 3 (1.08.2022): 24–31. http://dx.doi.org/10.31399/asm.edfa.2022-3.p024.

Pełny tekst źródła

Streszczenie:

Abstract This article demonstrates the value of atomic force microscopes, particularly the different electrical modes, for characterizing complex microelectronic structures. It presents experimental results obtained from deep trench isolation (DTI) structures using SCM and SSRM analysis with emphasis on the voltage applied by the AFM. From these measurements, a failure analysis workflow is proposed that facilitates AFM voltage optimization to reveal the structure of cross-sectioned samples, make comparisons, and determine the underlying cause of failures.

Style APA, Harvard, Vancouver, ISO itp.

44

Dorozhkin, P., E. Kuznetsov, A. Schokin, S. Timofeev i V. Bykov. "AFM + Raman Microscopy + SNOM + Tip-Enhanced Raman: Instrumentation and Applications". Microscopy Today 18, nr 6 (listopad 2010): 28–32. http://dx.doi.org/10.1017/s1551929510000982.

Pełny tekst źródła

Streszczenie:

Atomic Force Microscopy (AFM) has developed into a very powerful tool for characterization of surfaces and nanoscale objects. Many physical properties of an object can be studied by AFM with nanometer-scale resolution. Local stiffness, elasticity, conductivity, capacitance, magnetization, surface potential and work function, friction, piezo response—these and many other physical properties can be studied with over 30 AFM modes. What is typically lacking in information provided by AFM studies is the chemical composition of the sample and information about its crystal structure. To obtain this information other characterization techniques are required, such as Raman and fluorescence microscopy. The Raman effect (inelastic light scattering) provides extensive information about sample chemical composition, quality of crystal structure, crystal orientation, presence of impurities and defects, and so on. Information provided by Raman and fluorescence spectroscopy is complementary to the information obtained by AFM. So it is a natural requirement in many research fields to integrate these techniques in one piece of equipment—to provide comprehensive physical, chemical, and structural characterization of the same object. Of course, for routine studies of various samples, it is important to be able to obtain AFM and Raman/fluorescence images of exactly the same sample area, preferably with the same sample scan.

Style APA, Harvard, Vancouver, ISO itp.

45

Jazvinšćak Jembrek, Maja, Goran Šimić, Patrick R. Hof i Suzana Šegota. "Atomic force microscopy as an advanced tool in neuroscience". Translational Neuroscience 6, nr 1 (1.01.2015): 117–30. http://dx.doi.org/10.1515/tnsci-2015-0011.

Pełny tekst źródła

Streszczenie:

AbstractThis review highlights relevant issues about applications and improvements of atomic force microscopy (AFM) toward a better understanding of neurodegenerative changes at the molecular level with the hope of contributing to the development of effective therapeutic strategies for neurodegenerative illnesses. The basic principles of AFM are briefly discussed in terms of evaluation of experimental data, including the newest PeakForce Quantitative Nanomechanical Mapping (QNM) and the evaluation of Young’s modulus as the crucial elasticity parameter. AFM topography, revealed in imaging mode, can be used to monitor changes in live neurons over time, representing a valuable tool for high-resolution detection and monitoring of neuronal morphology. The mechanical properties of living cells can be quantified by force spectroscopy as well as by new AFM. A variety of applications are described, and their relevance for specific research areas discussed. In addition, imaging as well as non-imaging modes can provide specific information, not only about the structural and mechanical properties of neuronal membranes, but also on the cytoplasm, cell nucleus, and particularly cytoskeletal components. Moreover, new AFM is able to provide detailed insight into physical structure and biochemical interactions in both physiological and pathophysiological conditions.

Style APA, Harvard, Vancouver, ISO itp.

46

Boussu, K., B. Van der Bruggen, A. Volodin, J. Snauwaert, C. Van Haesendonck i C. Vandecasteele. "Roughness and hydrophobicity studies of nanofiltration membranes using different modes of AFM". Journal of Colloid and Interface Science 286, nr 2 (czerwiec 2005): 632–38. http://dx.doi.org/10.1016/j.jcis.2005.01.095.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

47

GENG, Y. L., i Z. H. SUN. "GROWTH MODES AND DEFECTS OF MANGANESE MERCURY THIOCYANATE CRYSTALS OBSERVED BY AFM". Surface Review and Letters 16, nr 01 (luty 2009): 19–22. http://dx.doi.org/10.1142/s0218625x09012238.

Pełny tekst źródła

Streszczenie:

Growth mechanisms and defects formation of the manganese mercury thiocyanate (MMTC) crystal have been investigated by atomic force microscopy (AFM). Both screw dislocation controlled growth and 2D nucleation growth occur on the {110} faces. Stacking faults are observed among dislocation hillocks and the formation of them probably results from the different crystallization orientations of different spirals. Hollow channels are found around the nucleation islands and the formation of them is due to the instability of the interface generated by the rapid nucleation and growth speeds.

Style APA, Harvard, Vancouver, ISO itp.

48

Xie, Xian Ning, Hong Jing Chung, Dipankar Bandyopadhyay, Ashutosh Sharma, Chorng Haur Sow, Andrew Anthony Bettiol i Andrew Thye Shen Wee. "Two Coexisting Modes in Field‐Assisted AFM Nanopatterning of Thin Polymer Films". Macromolecular Chemistry and Physics 209, nr 13 (3.07.2008): 1358–66. http://dx.doi.org/10.1002/macp.200800074.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

49

Rodriguez, D. J., A. V. Kotosonova, H. A. Ballouk, N. A. Shandyba, O. I. Osotova i A. S. Kolomiytsev. "Fabrication of probe tips via the FIB method for nanodiagnostics of the surface of solids by atomic force microscopy". Journal of Physics: Conference Series 2086, nr 1 (1.12.2021): 012204. http://dx.doi.org/10.1088/1742-6596/2086/1/012204.

Pełny tekst źródła

Streszczenie:

Abstract In this work, we carried out an investigation of commercial atomic force microscope (AFM) probes for contact and semi-contact modes, which were modified by focused ion beam (FIB). This method was used to modify the original tip shape of silicon AFM probes, by ion-etching and ion-enhance gas deposition. we show a better performance of the FIB-modified probes in contrast with the non-modified commercial probes. These results were obtained after using both probes in semi-contact mode in a calibration grating sample.

Style APA, Harvard, Vancouver, ISO itp.

50

Musa, Ishaq, Naser Qamhieh, Khadija Said, Saleh T. Mahmoud i Hussain Alawadhi. "Fabrication and Characterization of Aluminum Nitride Nanoparticles by RF Magnetron Sputtering and Inert Gas Condensation Technique". Coatings 10, nr 4 (21.04.2020): 411. http://dx.doi.org/10.3390/coatings10040411.

Pełny tekst źródła

Streszczenie:

Aluminum nitride nanoparticles (AlN-NPs) were fabricated by a RF magnetron sputtering and inert gas condensation technique. By keeping the source parameters and sputtering time of 4 h fixed, it was possible to produce AlN-NPs with a size in the range of 2–3 nm. Atomic force microscopy (AFM), Raman spectroscopy, X-ray diffraction (XRD), and UV-visible absorption were used to characterize the obtained AlN-NPs. AFM topography images showed quazi-sphere nanoparticles with a size ranging from 2 to 3 nm. The XRD measurements confirmed the hexagonal wurtzite structure of AlN nanoparticles. Furthermore, the optical band gap was determined by the UV-visible absorption spectroscopy. The Raman spectroscopy results showed vibration transverse-optical modes A1(TO), E1(TO), as well as longitudinal-optical modes E1(LO), A1(LO).

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „AFM Modes”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych