IMPURITY INDUCED WRINKLING PATTERNS IN METAL FILMS DEPOSITED ON SOFT ELASTIC SUBSTRATES

Metal (iron and nickel) films have been deposited on soft elastic polydimethylsiloxane (PDMS) substrates by direct current sputtering technique and the impurity induced wrinkling patterns are investigated by using optical microscopy and atomic force microscopy. It is found that the metal films can spontaneously form disordered wrinkles due to the isotropic compressive stress. In the vicinity of film impurities such as extraneous particles, linear defects, cracks and thickness-gradient film edges, the stress field becomes anisotropic owing to symmetry breaking and thus complex wrinkling patterns including straight stripes, herringbones, crossings, labyrinths and their transitions can be observed. The morphological evolutions, structural characteristics and physical mechanisms of the impurity induced wrinkles have been discussed and analyzed based on the continuum elastic theory.

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Conductance distribution in granular metal films: a combined study by conducting atomic force microscopy and computer simulation

Physica B Condensed Matter ◽

10.1016/s0921-4526(99)00679-1 ◽

2000 ◽

Vol 279 (1-3) ◽

pp. 98-101 ◽

Cited By ~ 5

Author(s):

E.Z. Luo ◽

A.B. Pakhomov ◽

Zhao-Qing Zhang ◽

M.-C. Chan ◽

I.H. Wilson ◽

...

Keyword(s):

Computer Simulation ◽

Atomic Force Microscopy ◽

Metal Films ◽

Force Microscopy ◽

Atomic Force ◽

Conductance Distribution

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Surface morphology of metal films deposited on mica at various temperatures observed by atomic force microscopy

Applied Surface Science ◽

10.1016/j.apsusc.2005.07.034 ◽

2006 ◽

Vol 252 (14) ◽

pp. 5083-5099 ◽

Cited By ~ 36

Author(s):

Morihide Higo ◽

Katsuya Fujita ◽

Yuya Tanaka ◽

Masaru Mitsushio ◽

Toshifumi Yoshidome

Keyword(s):

Atomic Force Microscopy ◽

Surface Morphology ◽

Metal Films ◽

Force Microscopy ◽

Atomic Force

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Topological Structures and Membrane Nanostructures of Erythrocytes after Splenectomy in Hereditary Spherocytosis Patients via Atomic Force Microscopy

Cell Biochemistry and Biophysics ◽

10.1007/s12013-016-0755-4 ◽

2016 ◽

Vol 74 (3) ◽

pp. 365-371 ◽

Cited By ~ 4

Author(s):

Ying LI ◽

Liyuan Lu ◽

Juan LI

Keyword(s):

Atomic Force Microscopy ◽

Cell Membrane ◽

Hereditary Spherocytosis ◽

Structural Characteristics ◽

Cytoskeletal Proteins ◽

Clinical Practices ◽

Average Cell ◽

Force Microscopy ◽

Atomic Force ◽

Membrane Ultrastructure

Abstract Hereditary spherocytosis is an inherited red blood cell membrane disorder resulting from mutations of genes encoding erythrocyte membrane and cytoskeletal proteins. Few equipments can observe the structural characteristics of hereditary spherocytosis directly expect for atomic force microscopy In our study, we proved atomic force microscopy is a powerful and sensitive instrument to describe the characteristics of hereditary spherocytosis. Erythrocytes from hereditary spherocytosis patients were small spheroidal, lacking a well-organized lattice on the cell membrane, with smaller cell surface particles and had reduced valley to peak distance and average cell membrane roughness vs. those from healthy individuals. These observations indicated defects in the certain cell membrane structural proteins such as α- and β-spectrin, ankyrin, etc. Until now, splenectomy is still the most effective treatment for symptoms relief for hereditary spherocytosis. In this study, we further solved the mysteries of membrane nanostructure changes of erythrocytes before and after splenectomy in hereditary spherocytosis by atomic force microscopy. After splenectomy, the cells were larger, but still spheroidal-shaped. The membrane ultrastructure was disorganized and characterized by a reduced surface particle size and lower than normal Ra values. These observations indicated that although splenectomy can effectively relieve the symptoms of hereditary spherocytosis, it has little effect on correction of cytoskeletal membrane defects of hereditary spherocytosis. We concluded that atomic force microscopy is a powerful tool to investigate the pathophysiological mechanisms of hereditary spherocytosis and to monitor treatment efficacy in clinical practices. To the best of our knowledge, this is the first report to study hereditary spherocytosis with atomic force microscopy and offers important mechanistic insight into the underlying role of splenectomy.

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Unusual DNA Structures Formed on Bare Highly Oriented Pyrolytic Graphite Surfaces Studied by Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927613000275 ◽

2013 ◽

Vol 19 (3) ◽

pp. 544-552 ◽

Cited By ~ 7

Author(s):

Zhiguo Liu ◽

Lin Zhao ◽

Yuangang Zu ◽

Shengnan Tan ◽

Yuanlin Wang ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Structural Characteristics ◽

Pyrolytic Graphite ◽

Dna Molecules ◽

Highly Oriented Pyrolytic Graphite ◽

Dna Structures ◽

Force Microscopy ◽

Single Dna Molecules ◽

Research Areas ◽

Atomic Force

AbstractIt is important to know the detailed DNA structure on carbonaceous surfaces for further application of DNA-functionalized carbonaceous materials in diverse research areas. In this study, the topographic and structural characteristics of the separated single DNA molecules and their assembly on highly oriented pyrolytic graphite (HOPG) surfaces have been investigated by atomic force microscopy (AFM). AFM results indicate that both circular and linear DNA molecules tend to form hexagonal patterns along with some unusual structures that include node, protrusion, cruciform, parallel single-stranded DNA (ssDNA), and compact zigzag. Furthermore, parallel ssDNA patterns and their crossed structures have been obtained under high-temperature conditions. Our AFM results reveal that a bare HOPG surface can induce DNA molecules to form various unusual structures. This finding is helpful for understanding the adsorption behavior of DNA on other carbonaceous surfaces such as carbon nanotubes and graphene. In addition, the hexagonal DNA patterns in this study are similar to those formed on the alkylamine-modified HOPG surface, which implies that a bare HOPG, without any chemical modification, has a strong ability to align biomolecules. This study could expand our knowledge of the diversities of DNA structures and the aligning ability of carbonaceous surfaces.

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Simultaneous atomic force microscopy measurement of topography and contact resistance of metal films and carbon nanotubes

Review of Scientific Instruments ◽

10.1063/1.1590750 ◽

2003 ◽

Vol 74 (8) ◽

pp. 3653-3655 ◽

Cited By ~ 10

Author(s):

M. Stadermann ◽

H. Grube ◽

J. J. Boland ◽

S. J. Papadakis ◽

M. R. Falvo ◽

...

Keyword(s):

Carbon Nanotubes ◽

Atomic Force Microscopy ◽

Contact Resistance ◽

Metal Films ◽

Atomic Force Microscopy Measurement ◽

Force Microscopy ◽

Atomic Force ◽

Microscopy Measurement

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Ultrastructure and fourier transform infrared spectrum of exopolysaccharide produced by Lactobacillus rhamnosus NBRC 3425

Annals of Tropical Research ◽

10.32945/atr4219.2020 ◽

2020 ◽

pp. 117-127

Author(s):

Ivy Emnace

Keyword(s):

Electron Microscopy ◽

Atomic Force Microscopy ◽

Fourier Transform ◽

Structural Characteristics ◽

Lactobacillus Rhamnosus ◽

Test Organism ◽

Fourier Transform Infrared ◽

Oh Groups ◽

Force Microscopy ◽

Atomic Force

In the search for exopolysaccharide (EPS)—producing LAB strains as potential additive for industrial applications, EPS produced by Lactobacillus rhamnosus NBRC 3425 was subjected to partial characterization to provide further information on its structure and composition. The crude EPS was subjected to scanning electron microscopy (SEM), atomic force microscopy (AFM),transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). Results of TEM analysis confirmed that the test organism is an EPS producer due to the presence of an unstained, clear cell wall or halo that surrounds the bacterial cell typical of a capsular EPS. SEM analysis showed that the crude EPS has pores and spaces between particles. Atomic force microscopy (AFM) at a concentration of 10μg per mL revealed spike-shaped lumps with an average size of 17.81±2.89nm. The FTIR spectrum suggested the presence of hydroxyl (OH) groups of carbohydrate and carbonyl group (C=O). Results showed that based on its structural characteristics, such EPS has the potential for use as stabilizer in food products.

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