Structure and Nanocrystallites of Ni and NiO Three Dimensional Ordered Macromeshes

2001 ◽  
Vol 703 ◽  
Author(s):  
W.L. Zhou ◽  
L. Xu ◽  
A.A. Zakhidov ◽  
R.H. Baughman ◽  
J.B. Wiley
Keyword(s):  
Electron Microscope ◽  
Three Dimensional ◽  
Temperature Treatment ◽  
Inverse Opal ◽  
Preferential Growth ◽  
Transmission Electron ◽  
Higher Temperature ◽  
Ordered Macroporous ◽  
Nio Nanocrystals ◽  
20 Nm

ABSTRACTThree dimensional Ni and NiO inverse opal macromeshes were characterized by scanning electron microscope (SEM) and transmission electron microscope (SEM). The octahedral cubes of the macroporous Ni were found mostly grown as single crystals with staking faults and microtwins. There was no preferential growth of these cubes as determined by selected area diffraction pattern (SADP). Some NiO nanocrystals with size of about 5 nm were formed on the surface of inverse Ni opal membrane during etching away of silica spheres. The oxidation of Ni mesh turned it into NiO macromesh with grain size of about 20 nm at 550°C. The nanocrystalline NiO mesh is suitable for further fabrication of three dimensional nanobeads. By annealing the meshes at 650°C, the NiO nanograins grew to a size of over 50 nm. This three dimensional ordered macroporous structure with higher temperature treatment is considered as stable and important for further application.

scholarly journals Meso-Scale Transmission Electron Microscope Tomography Applied for Wax Distribution in Toner Particles

2013 ◽  
Vol 19 (S5) ◽  
pp. 58-61 ◽  
Author(s):  
Mino Yang ◽  
Jun-Ho Lee ◽  
Hee-Goo Kim ◽  
Euna Kim ◽  
Young-Nam Kwon ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Three Dimensional ◽  
Chromatic Aberration ◽  
Laser Printer ◽  
Medium Voltage ◽  
Transmission Electron ◽  
Z Contrast ◽  
Contrast Image

AbstractDistribution of wax in laser printer toner was observed using an ultra-high-voltage (UHV) and a medium-voltage transmission electron microscope (TEM). As the radius of the wax spans a hundred to greater than a thousand nanometers, its three-dimensional recognition via TEM requires large depth of focus (DOF) for a volumetric specimen. A tomogram with a series of the captured images would allow the determination of their spatial distribution. In this study, bright-field (BF) images acquired with UHV-TEM at a high tilt angle prevented the construction of the tomogram. Conversely, the Z-contrast images acquired by the medium-voltage TEM produced a successful tomogram. The spatial resolution for both is discussed, illustrating that the image degradation was primarily caused by beam divergence of the Z-contrast image and the combination of DOF and chromatic aberration of the BF image from the UHV-TEM.

Fast Throughput Low Voltage Scanning Transmission Electron Microscope Imaging of Nano-Resolution Three Dimensional Tissue

2009 ◽  
Vol 15 (S2) ◽  
pp. 642-643
Author(s):  
M Bolorizadeh ◽  
HF Hess
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Low Voltage ◽  
Three Dimensional ◽  
Scanning Transmission Electron Microscope ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Microscope Imaging ◽  
Electron Microscope Imaging ◽  
Voltage Scanning

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

scholarly journals Synthesis, Characterization and Photocatalytic Activity of Nanocrystalline First Transition-Metal (Ti, Mn, Co, Ni and Zn) Oxisde Nanofibers by Electrospinning

2018 ◽  
Vol 9 (1) ◽  
pp. 8 ◽  
Author(s):  
Yu Chen ◽  
Weipeng Lu ◽  
Yanchuan Guo ◽  
Yi Zhu ◽  
Haojun Lu ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Transition Metal ◽  
Metal Oxide ◽  
Specific Surface ◽  
Three Dimensional ◽  
Photogenerated Electron ◽  
Practical Applications ◽  
Surface Areas ◽  
Tio2 Nanofiber ◽  
Transmission Electron

In this work, five nanocrystalline first transition-metal (Ti, Mn, Co, Ni and Zn) oxide nanofibers were prepared by electrospinning and controlled calcination. The morphology, crystal structure, pore size distribution and specific surface area were systematically studied by scanning electron microscope (SEM), transmission electron microscope (TEM), surface and pore analysis, and thermo gravimetric analyzer (TGA). The results reveal that the obtained nanofibers have a continuously twisted three-dimensional scaffold structure and are composed of neat nanocrystals with a necklace-like arrangement. All the samples possess high specific surface areas, which follow the order of NiO nanofiber (393.645 m2/g) > TiO2 nanofiber (121.445 m2/g) > ZnO nanofiber (57.219 m2/g) > Co3O4 nanofiber (52.717 m2/g) > Mn2O3 nanofiber (18.600 m2/g). Moreover, the photocatalytic degradation of methylene blue (MB) in aqueous solution was investigated in detail by employing the five kinds of metal oxide nanofibers as photocatalysts under ultraviolet (UV) irradiation separately. The results show that ZnO, TiO2 and NiO nanofibers exhibit excellent photocatalytic efficiency and high cycling ability to MB, which may be ascribed to unique porous structures and the highly efficient separation of photogenerated electron-hole pairs. In brief, this paper aims to provide a feasible approach to achieve five first transition-metal oxide nanofibers with excellent performance, which is important for practical applications.

scholarly journals Ultrastructure of Human Fertile Hydatid Cysts Using a Scanning Electron Microscope (SEM)

2020 ◽  
Vol 1 (3) ◽  
pp. 52-55
Author(s):  
Hadi M. Hamza Al-Mayali ◽  
Hind A. Abdul Kadhim
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Three Dimensional ◽  
Zoonotic Diseases ◽  
Hydatid Cysts ◽  
Germinal Layer ◽  
Transmission Electron ◽  
The World ◽  
Laminated Layer ◽  
Scanning Electron

Introduction: Echinococcosis and hydatidosis caused by the metacestode of Echinococcus granulosus are among the most important zoonotic diseases in the world. This study aims to study the ultrastructure of fertile hydatid cysts that infect humans using a scanning electron microscope (SEM). Materials and Methods: Twenty samples of human fertile hydatid cysts were collected from the human liver and lung after performing surgery operations and examined with an SEM. Results: The results of the electron microscopy with different magnifications revealed that the laminated layer (LL) consists of sheets that appeared more compact and aligned. The brood capsules appeared, consisting of a net of finger-shaped structures that emerged from bulges of various sizes and shapes. Conclusion: Under a transmission electron microscope, it was found that the LL had a coherent and flexible structure, settling on a three-dimensional microscopic network of hydrophilic fibers, with high humidity. These fibers were arranged irregularly and had a diameter of about 10 nm; therefore, the fibers adjacent to the germinal layer (GL) were possibly attached to microtriches of tegument, which reached a thickness of 1 mm in the LL.

Self-Organized Composition Modulation In Omvpe Ga1−xInxAsySb1−y/GaSb Epitaxial Heterostructures

1999 ◽  
Vol 583 ◽  
Author(s):  
Y-C. Chen ◽  
V. Bucklen ◽  
K. Rajan ◽  
C. A. Wang ◽  
G. W. Charache ◽  
...  
Keyword(s):  
Cross Section ◽  
Three Dimensional ◽  
Component Composition ◽  
Organometallic Vapor Phase Epitaxy ◽  
Composition Modulation ◽  
Self Organized ◽  
Transmission Electron ◽  
Epitaxial Heterostructures ◽  
20 Nm ◽  
Lattice Matched

AbstractMicrostructures of lattice-matched Ga1−xInxAsySb1−y grown by organometallic vapor phase epitaxy (OMVPE) on (100) 6°→ (111)B GaSb substrates have been examined in detail by transmission electron microscopy. A three-dimensional self-organized composition modulation (SOCM) microstructure was found with an orientation inclined 10 degrees to the surface orientation when viewed in (011) cross-section. The periodicity of the SOCM increased from ˜13 nm to 20 nm, as x increased from 0.1 to 0.2 while the orientation of the SOCM remained the same. The fact that the orientation was not sensitive to the component composition indicated that substrate misorientation plays a major role in deciding this SOCM orientation. This may open fabrication opportunities for three-dimensional natural superlattices by engineering on the substrate misorientation.

Effect of Aging Treatment on Damping Capacity in Mncunife Alloy

2012 ◽  
Vol 246-247 ◽  
pp. 1158-1162
Author(s):  
Xu Fu ◽  
Ning Li ◽  
Yu Hua Wen ◽  
Jing Teng ◽  
Ying Zhang
Keyword(s):  
Electron Microscope ◽  
Aging Treatment ◽  
Damping Capacity ◽  
Torsion Pendulum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The Relationship

M2052 alloys with various aging treatments are obtained in order to investigate the relationship between aging treatment and damping capacity by the torsion pendulum, X-Ray Diffraction (XRD) and Transmission Electron Microscope (TEM) methods. The results show that M2052 can obtain high damping capacity (δ>0.2) when aged at a range from 400°C to 450°C, and the damping capacity after aged at a lower temperature is higher than that aged at a higher temperature for the maximum values. TEM and XRD results show that fcc-fct transformation occurs after aging treatment. The volumes of fct structures are one of reason to affect the damping capacity in M2052 alloy. The better understanding aging treatment could promote the applications of M2052 alloy.

Electron Microscope Studies of Some Vapor Deposited Materials: Nucleation, Epitaxial Growth and Surface Topography

1991 ◽  
Vol 237 ◽  
Author(s):  
William Krakow
Keyword(s):  
Electron Microscope ◽  
Epitaxial Growth ◽  
Three Dimensional ◽  
Film Surface ◽  
Ex Situ ◽  
Growth Regime ◽  
Growth Modes ◽  
Transmission Electron ◽  
Resolution Electron ◽  
High Resolution Electron Microscope

ABSTRACTThe nucleation and epitaxial growth of deposits at both low and high temperature substrate conditions and the resulting two and three dimensional growth modes have been investigated using electron diffraction and transmission electron microscopy. At high temperatures, the growth of small particles such as Au, Pt and Ge grown under low rate conditions similar to MBE are revealed by lattice imaging. Using an intermediate bufler layer Ag film, surface growth of (100) and (310) Au thin film layers are revealed by diffraction contrast to be in a step ledge growth regime. While the above investigations were performed ex situ to the microscope vacuum environment, an in situ evaporator has been also been installed on a high resolution electron microscope. Observations can be made in real time of cluster growth from atomic diameters on up. The resulting atomic motion around cluster edges is similar in appearance to surface melting.

scholarly journals Effects of Crystallinity on the Photocatalytic Polymerization of 3,4-Ethylenedioxythiophene over CsPbBr3 Inverse Opals

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1331
Author(s):  
Siwei Zhao ◽  
Shaohua Jin ◽  
Huanmin Liu ◽  
Shengfu Li ◽  
Kun Chen
Keyword(s):  
Colloidal Crystal ◽  
Three Dimensional ◽  
Inverse Opal ◽  
Porous Structures ◽  
Novel Approach ◽  
Transmission Electron ◽  
Hierarchical Porous ◽  
Antisolvent Crystallization ◽  
Colloidal Crystal Templating ◽  
High Absorption Coefficient

Due to their high absorption coefficient and long carrier lifetime, halide perovskites are promising candidates for photocatalysts. For this study, the antisolvent crystallization protocol and the colloidal crystal templating approach were combined to fabricate the highly crystalline cesium lead bromide perovskite with inverse opal morphology (IO-CsPbBr3). Scanning electron microscopy and transmission electron microscope images demonstrate the three-dimensional well-ordered porous structures of the IO-CsPbBr3 and their single-crystalline features. The presented approach not only provides hierarchical porous structures but also enhances overall crystallinity. When used as catalysts to promote the polymerization of 2,2′,5′,2″-ter-3,4-ethylenedioxythiophene, the highly crystalline IO-CsPbBr3 exhibits a superior photocatalytic performance compared to its polycrystalline counterpart. Furthermore, the morphology and the crystalline structure of the highly crystalline IO-CsPbBr3 are well preserved under photocatalytic conditions. This novel approach enables the preparation of a halide perovskite inverse opal with high crystallinity.

Analysis of electron-specimen interactions of thick biological specimens in Transmission Electron Microscopy at 200 KEV

1993 ◽  
Vol 51 ◽  
pp. 204-205
Author(s):  
Karen F. Han ◽  
Alexander J. Gubbens ◽  
Abraham J. Koster ◽  
Michael B. Braunfeld ◽  
John W. Sedat ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Mass Density ◽  
Three Dimensional ◽  
Chromatic Aberration ◽  
Background Intensity ◽  
Objective Lens ◽  
Dimensional Electron ◽  
Accurate Representation ◽  
Transmission Electron

The primary project of our laboratory is the investigation of chromatin structure by three dimensional electron microscope tomography. The goal is to understand how 30nm fibers fold into higher order chromatin structures. Three dimensional tomography involves the reconstruction of an object by combining multiple projection views of the object at different tilt angles. Due to the electronspecimen interaction and the characteristics of lens aberration in the electron microscope, however, the image is not always an accurate representation of the projected object mass density. In this abstract, we analyze the various types of electron-specimen interaction for thick biological specimens up to 0.7 microns thickness.Electron-specimen interactions include single elastic and inelastic, and multiple elastic and inelastic scattering. Of the imaging electrons, the single elastic and the plasmon electrons give rise to image intensities that can be linearly related to the projected object mass density. Multiply scattered elastic electrons contribute to an increase in background intensity. In addition, due to the chromatic aberration of the TEM’s objective lens, multiply scattered inelastic electrons cause a blurring of the image because of an effective broadening of the focus spread.

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