scholarly journals Preparation, Characterization, and Application of Magnetic Fe-SBA-15 Mesoporous Silica Molecular Sieves

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Huayu Huang ◽  
Yongsheng Ji ◽  
Zhenfeng Qiao ◽  
Chuande Zhao ◽  
Jianguo He ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Magnetic Materials ◽  
Magnetic Separation ◽  
Electron Micrographs ◽  
Molecular Sieves ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Metal Form ◽  
Scanning Electron

Magnetic Fe-SBA-15 mesoporous silica molecular sieves were prepared, characterized, and used for magnetic separation. Wet impregnation, drying, and calcination steps led to iron inclusion within the mesopores. Iron oxide was reduced to the metal form with hydrogen, and the magnetic Fe-SBA-15 was obtained. Fourier-transform infrared spectroscopy confirmed the preparation process from the oxide to metal forms. The structure of magnetic materials was confirmed by Mössbauer spectra. Powder X-ray diffraction data indicated that the structure of Fe-SBA-15 retained the host SBA-15 structure. Brunauer-Emmett-Teller analysis revealed a decrease in surface area and pore size, indicating Fe-SBA-15 coating on the inner surfaces. Scanning electron micrographs confirmed the decrease in size for modified SBA-15 particles. From scanning electron micrographs, it was found that the size of the modified SBA-15 particles decreased. Transmission electron micrographs also confirmed that modified SBA-15 retained the structure of the parent SBA-15 silica. Fe-SBA-15 exhibited strong magnetic properties, with a magnetization value of 8.8 emu g-1. The iron content in Fe-SBA-15 was determined by atom adsorption spectroscopy. Fe-SBA-15 was successfully used for the magnetic separation of three aromatic compounds in water. Our results suggest wide applicability of Fe-SBA-15 magnetic materials for the rapid and efficient separation of various compounds.

The ultrastructure of the epidermis of the redia and cercaria of Parorchis acanthus, Nicoll. A study by scanning and transmission electron-microscopy

Parasitology ◽  
1971 ◽  
Vol 62 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Gwendolen Rees
Keyword(s):  
Electron Micrographs ◽  
Technical Assistance ◽  
Ventral Surface ◽  
The Body ◽  
Muscle Fibres ◽  
Scanning Electron Micrographs ◽  
Large Area ◽  
Transmission Electron ◽  
Parorchis Acanthus ◽  
Scanning Electron

Scanning electron-micrographs have shown the covering of microvilli on the surface of the redia of Parorchis acanthus. In the contracted state the elongated microvilli with bulbous extremities seen in the surface grooves may be the result of compression. The surface of the epidermis of the cercaria is smooth on a large area of the ventral surface and lattice-like with microvilli, laterally, anteriorly, dorsally and on the tail. The spines on the body can be withdrawn into sheaths by the contraction of muscle fibres inserted into the basement lamina below each spine.I would like to express my sincere gratitude to Dr I. ap Gwynn of this department for preparing the scanning electron-micrographs and the School of Engineering Science, University of North Wales, Bangor for the use of their stereoscan. I should also like to thank Mr M. C. Bibby for technical assistance and Professor E. G. Gray and Dr W. Sinclair for assistance with the transmission electron-micrographs.

Synthesis, Characterization and Catalytic Application of Mesoporous PW/SBA-15 for Epoxidation of α-Pinene

2012 ◽  
Vol 538-541 ◽  
pp. 2382-2386 ◽  
Author(s):  
Dan Dan Zhu ◽  
Chun Hua Wu ◽  
Chang Fu Zhuang ◽  
Guan Ben Du ◽  
Jia Yan Zhang
Keyword(s):  
Electron Micrographs ◽  
Hexagonal Structure ◽  
Scanning Electron Micrographs ◽  
The Novel ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Catalytic Application ◽  
Transmission Electron ◽  
Ft Ir ◽  
High Degree

Supported phosphotungstic acid SBA-15 were synthesized under hydrothermal conditions and characterized by X-ray diffraction (XRD), N2 adsorption, transmission electron micrographs (TEM), scanning electron micrographs (SEM), Fourier-transform infrared spectroscopy (FT-IR). XRD and FT-IR results indicated that the substitution of tungsten occurs in the silicate framework structure of SBA-15. TEM and SEM investigations confirmed the presence of ordered high degree ordering hexagonal structure in the novel PW/SBA-15 material. Their catalytic activity was evaluated in the epoxidation of α-pinene. 2,3-epoxypinane was the main product. The results of epoxidation of α-pinene by PW(40)/SBA-15 were fellows: the conversion rate of α-pinene and the selectivity were 87.61% and 79.90% respectively.

scholarly journals Characterization of Dark-Colored Nanoporous Anodic Films on Zinc

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1014
Author(s):  
Ryoya Masuda ◽  
Damian Kowalski ◽  
Sho Kitano ◽  
Yoshitaka Aoki ◽  
Taisuke Nozawa ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Metal Film ◽  
Metal Nanoparticle ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Anodic Films ◽  
X Ray ◽  
Transmission Electron ◽  
Film Interface

In this study, zinc is anodized at different voltages in 0.1 mol·dm−3 KOH electrolyte to form nanoporous anodic films. Dark-colored anodic films are formed at anodizing voltages ≤6 V, whereas colorless anodic films are developed at voltages ≥7 V. The anodic films formed at all voltages consist of crystalline ZnO, which was identified by X-ray diffraction and Raman spectroscopy. The Raman spectra of the dark-colored anodic films show the enhanced intensity of the LO phonon mode due to electric-field-induced Raman scattering, which may be associated with the presence of metallic Zn nanoparticles in the anodic films. Scanning electron micrographs and transmission electron micrographs of the cross-section of the dark-colored anodized zinc reveal the formation of two-layer porous anodic films with a highly rough metal/film interface. In contrast, nanoporous anodic films of uniform thickness with a relatively flat metal/film interface are formed for the colorless anodized zinc. The transmission electron microscopy (TEM)/energy dispersive X-ray spectroscopy (EDS) analysis suggested the presence of zinc nanoparticles in the dark-colored anodic films. The non-uniform anodizing and the formation of metal-nanoparticle-dispersed porous anodic films cause the formation of dark-colored anodic films on zinc.

Synthesis of NaY Zeolite Molecular Sieves from Calcined Diatomite

2011 ◽  
Vol 236-238 ◽  
pp. 362-368
Author(s):  
Jin Hong Li ◽  
Zhen Qing Chi ◽  
Hui Fen Chen
Keyword(s):  
Electron Microscope ◽  
Molecular Sieves ◽  
High Yield ◽  
Mass Ratio ◽  
X Ray Diffraction ◽  
Nay Zeolite ◽  
Hydrothermal Temperature ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

NaY zeolite molecular sieves have been synthesized using diatomite as a main starting material via a hydrothermal method. In this approach, the mixture of diatomite and Na2CO3 in mass ratio of 1.0/1.46 was first calcined at temperature of 830 °C for about 1.5 h. The calcined materials were then dissolved in water to obtain a solution and the composition is 15.1 Na2O : 1 Al2O3 : 11.5 SiO2 : 832 H2O. The solution was used to synthesize NaY zeolite by the crystals seeds (27.76Na2O·1.00Al2O3·25.07SiO2·305.66H2O) via hydrothermal treatment. The hydrothermal temperature is 100 °C and the percentage of added crystal seeds is 10% (volume) relative to calcined materials. The obtained zeolite was identified by X-ray diffraction (XRD), and was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and nitrogen sorption analysis, which showed that a high yield of NaY type with a high crystalinity was obtained.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

The Effect of the Microstructure of Diffusion Barriers on the Palladium Activation for Electroless Copper Deposition

2002 ◽  
Vol 716 ◽  
Author(s):  
Seok Woo Hong ◽  
Yong Sun Lee ◽  
Ki-Chul Park ◽  
Jong-Wan Park
Keyword(s):  
Electron Microscopy ◽  
Diffusion Barriers ◽  
Copper Deposition ◽  
X Ray Diffraction ◽  
Plan View ◽  
X Ray ◽  
Transmission Electron ◽  
Electroless Copper ◽  
Sheet Resistance Measurement ◽  
Scanning Electron

AbstractThe effect of microstructure of dc magnetron sputtered TiN and TaN diffusion barriers on the palladium activation for autocatalytic electroless copper deposition has been investigated by using X-ray diffraction, sheet resistance measurement, field emission scanning electron microscopy (FE-SEM) and plan view transmission electron microscopy (TEM). The density of palladium nuclei on TaN diffusion barrier increases as the grain size of TaN films decreases, which was caused by increasing nitrogen content in TaN films. Plan view TEM results of TiN and TaN diffusiton barriers showed that palladium nuclei formed mainly on the grain boundaries of the diffusion barriers.

A new genus and four new species of millipedes from Tasmania, Australia (Diplopoda: Polydesmida: Dalodesmidae), with notes on male leg setae in some Tasmanian dalodesmids

Zootaxa ◽  
2004 ◽  
Vol 558 (1) ◽  
pp. 1 ◽  
Author(s):  
ROBERT MESIBOV
Keyword(s):  
New Species ◽  
Electron Micrographs ◽  
Type Species ◽  
New Genus ◽  
Scanning Electron Micrographs ◽  
Scanning Electron

Bromodesmus catrionae n. gen., n. sp. (type species), B. militaris n. sp., B. riparius n. sp. and B. rufus n. sp. are described. The new genus is characterized by greatly reduced paranota and a gonopod telopodite expanded at the distal end into a posteriorly concave hood fringed with teeth; the hood partly protects a long, curved, acutely pointed solenomerite. Male leg setation in the type species of six Tasmanian dalodesmid genera is briefly discussed and illustrated with scanning electron micrographs. The sphaerotrichome shaft is sharply pointed in Atrophotergum; gently tapered in Dasystigma, Lissodesmus and Tasmanodesmus; expanded at the tip in Bromodesmus; and entirely absent in Gasterogramma. Tips of the setae forming the dense ventral brush on male podomeres are gently tapered in Dasystigma and Lissodesmus, truncated in Gasterogramma, expanded in Bromodesmus and forked in Tasmanodesmus.

Organoclay-reinforced polyethersulfone-modified epoxy-based hybrid nanocomposites

2011 ◽  
Vol 23 (7) ◽  
pp. 526-534 ◽  
Author(s):  
Yang Wang ◽  
Boming Zhang ◽  
Jinrui Ye
Keyword(s):  
Electron Microscopy ◽  
Fracture Toughness ◽  
Electron Microscope ◽  
Optical Microscope ◽  
Mechanical Analysis ◽  
Hybrid Nanocomposites ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Modified Epoxy ◽  
Scanning Electron

Hybrid nanocomposites were successfully prepared by the incorporation of polyethersulfone (PES) and organoclay into epoxy resin. They had higher fracture toughness than the prepared PES/epoxy blend and organoclay/epoxy nanocomposites. The microstructures of the hybrid nanocomposites were studied. They were comprised of homogeneous PES/epoxy semi-interpenetrating network (semi-IPN) matrices and organoclay micro-agglomerates made up of tactoid-like regions composed of ordered exfoliated organoclay with various orientations. The former was confirmed with dynamic mechanical analysis, scanning electron microscopy and transmission electron microscopy, while the latter was successfully observed with X-ray diffraction measurements, optical microscope, scanning electron microscope and transmission electron microscope. The improvement of their fracture toughness was due to the synergistic toughening effect of the PES and the organoclay and related to their microstructures.

Aphid parasitoids infesting cotton, citrus, tobacco, and cereal crops in southeastern Europe: aphid-plant associations and keys

2005 ◽  
Vol 137 (5) ◽  
pp. 516-531 ◽  
Author(s):  
Nickolas G. Kavallieratos ◽  
Željko Tomanović ◽  
Christos G. Athanassiou ◽  
Petr Starý ◽  
Vladimir Žikić ◽  
...  
Keyword(s):  
Electron Micrographs ◽  
Separate Group ◽  
Cereal Crops ◽  
Scanning Electron Micrographs ◽  
Southeastern Europe ◽  
Line Drawings ◽  
Plant Associations ◽  
New Information ◽  
Aphid Parasitoids ◽  
Scanning Electron

AbstractWe present new information on the parasitoids (Hymenoptera: Braconidae: Aphidiinae) of aphids infesting cotton, tobacco, citrus, and cereal agroecosystems in southeastern Europe. Nineteen species are keyed and illustrated with scanning electron micrographs and line drawings. The aphidiines presented in this work have been identified from 18 aphid taxa. Furthermore, 96 original parasitoid–aphid–plant associations are presented. Cotton, tobacco, and citrus agroecosystems are connected through aphids and their parasitoids, whereas cereal agroecosystems represent a separate group of associations.

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