Assessment on the Release of Magnetite Nanoparticles Embedded with PVA Nanofiber in Hydrodynamics

2016 ◽  
Vol 41 ◽  
pp. 31-41
Author(s):  
Vikram Srinivas ◽  
Vasanthakumari Raju
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Polyvinyl Alcohol ◽  
Magnetite Nanoparticles ◽  
Average Diameter ◽  
Spectroscopic Technique ◽  
Release Mechanism ◽  
Static Mode ◽  
Magnetite Nanoparticle ◽  
Polymer Nanofiber

Magnetite nanoparticle with average size 7-10 nm was embedded with biocompatible polyvinyl alcohol nanofiber and the average diameter of nanofiber is 115 nm. The nanofiber was further assembled over polymeric mesh to analyse the release mechanism of nanoparticles from polymer nanofiber. A hydrodynamics setup was constructed to study this system. Prior to hydrodynamics the nanofiber was allowed to react with water in static mode and observed that the magnetite nanoparticles were released from the nanofiber with increase in time. UV-Visible Spectrophotometer is used for analysis of absorbance and transmittance of polyvinyl alcohol-magnetite nanoparticles solution, nanofiber and films. High-resolution scanning electron microscopy is used to analyze the dimension of nanofiber; High-resolution transmission electron microscopy is used to find the size of magnetite nanoparticles. Here, an online spectroscopic technique was used to study the release mechanism of nanoparticles from nanofibers samples of different layers during hydrodynamics. The results reveal that the quantity of magnetite nanoparticles can be controlled by embedding into nanofibers during hydrodynamics. Also, the spectroscopic results indicate the quantity of nanoparticles released from nanofiber. This mechanism can be utilized to control the required quantity of nanoparticles to release at particular location through a polymer mesh assembly.

High resolution scanning near field mapping of enhancement on SERS substrates: comparison with photoemission electron microscopy

2016 ◽  
Vol 18 (14) ◽  
pp. 9405-9411 ◽  
Author(s):  
C. Awada ◽  
J. Plathier ◽  
C. Dab ◽  
F. Charra ◽  
L. Douillard ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Near Field ◽  
Spectroscopic Technique ◽  
Proof Of Concept ◽  
Sers Substrates ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Enhanced Raman Scattering ◽  
Photoemission Electron

The need for a dedicated spectroscopic technique with nanoscale resolution to characterize SERS substrates pushed us to develop a proof of concept of a functionalized tip–surface enhanced Raman scattering (FTERS) technique.

SILICON CARBIDE NANOWIRES FROM POLYVINYL ALCOHOL/SILICA ELECTROSPUN NANOFIBERS

NANO ◽  
2011 ◽  
Vol 06 (01) ◽  
pp. 41-45 ◽  
Author(s):  
H. DELAVARI H. ◽  
M. KOKABI
Keyword(s):  
Electron Microscopy ◽  
Silicon Carbide ◽  
Polyvinyl Alcohol ◽  
Gas Flow ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Sic Nanowires ◽  
Transmission Electron ◽  
Temperature Scanning ◽  
Vs Mechanism

The catalyst-free synthesis of silicon carbide (SiC) nanowires was carried out from polyvinyl alcohol (PVA)/silica electrospun nanofibers at high temperature. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and thermogravimetery analysis (TGA) were employed to study morphology and formation of SiC nanowires. Based on the TGA analysis, the carbon yield was increased when inert gas flow rate and heating rate decreased and polymeric nanofibers has been stabilized. The XRD and TEM results showed that the produced nanowires were crystalline β- SiC and rather homogeneous in thickness with an average diameter around 50 to 70 nm and a length of more than 10 μm. Finally, a possible growth mechanism of β- SiC nanowire based on a vapor–solid (VS) mechanism was proposed.

The Raft-Like Structure of Supported PtRu5

1997 ◽  
Vol 497 ◽  
Author(s):  
J. C. Yang ◽  
S. Bradley ◽  
M. N. Nashner ◽  
R. Nuzzo ◽  
J. M. Gibson
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Analytical Electron Microscopy ◽  
Average Diameter ◽  
Atomic Concentration ◽  
Analytical Electron ◽  
Microscopy Techniques

ABSTRACTWe have examined supported PtRus specimens by a variety of electron microscopy techniques, including high resolution, analytical and a novel mass-spectroscopic electron microscopy techniques. Analytical electron microscopy results showed that the relative atomic concentration of Pt to Ru for each PtRu5 cluster is 1 to 5. The average diameter of the clusters was a 15.6Å, and the average number of atoms was measured to be 24 atoms per cluster. The combination of these techniques demonstrate that the PtRu5 clusters are raft-like on the carbon black support.

scholarly journals Derivatized silica spheres as immunospecific markers for high resolution labeling in electron microscopy.

1978 ◽  
Vol 78 (2) ◽  
pp. 309-318 ◽  
Author(s):  
K R Peters ◽  
G Rutter ◽  
H H Gschwender ◽  
W Haller
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Cell Surface ◽  
Hela Cells ◽  
Average Diameter ◽  
Surface Antigens ◽  
Silica Sphere ◽  
Silica Spheres ◽  
Cell Surface Antigens ◽  
Controlled Pore Glass

For high resolution labeling of influenza virus cell surface antigens on HeLa cells, an immunospecific marker is used with silica sphere cores of 13--14 nm average diameter. These markers are formed using commercially available silica sphere sols. Two other size ranges are available, 7--8 nm and 22--25 nm. The steps for chemical derivatization are described in detail. Amino and aldehyde functions are covalently introduced onto the sphere surface. Sols of these derivatized silica spheres (DSS) are physicochemically stable and therefore usable for years. Coupling of IgG to DSS followed by permeation chromatography on controlled pore glass results in size-defined immunospecific silica sphere markers (DSS-markers). Saturation labeling of cell surface antigens on HeLa cells on cover slips is obtained with the final sphere concentration of 10(14) DSS-marker/cm3 within 20 min. With usual protective conditions, the marker stability and labeling ability are preserved for months. The visibility and the fine structure of the DSS-marker on cell surfaces are shown by using transmission electron microscopy (TEM) with stereo replicas and ultrathin sections.

Synthesis and Characterization of Carbon Nanotube-Nickel/Nickel Oxide Core/shell Nanoparticle Heterostructures Incorporated in Polyvinyl Alcohol Hydrogel

2010 ◽  
Vol 1272 ◽  
Author(s):  
Wenwu Shi ◽  
Kristy Crews ◽  
Nitin Chopra
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotube ◽  
Polyvinyl Alcohol ◽  
Nickel Oxide ◽  
Photoelectron Spectroscopy ◽  
Average Diameter ◽  
Core Shell ◽  
Shell Nanoparticles ◽  
Core Shell Nanoparticles ◽  
Pva Hydrogel

AbstractCarbon nanotube (CNT)-nickel/nickel oxide (Ni/NiO) core/shell nanoparticles (CNC) heterostructures were prepared in a unique single-step synthetic route by direct chemical precipitation of nanoparticles on CNT surface. Chemical vapor deposition (CVD)-grown CNTs (average diameter ˜42.7±12.3 nm) allowed for direct nucleation and uniform coating of Ni/NiO core/shell nanoparticles (average diameter ˜11.8±1.7 nm). The crystal structure, morphology, and phases in CNC heterostructures were studied using high resolution transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Subsequently, the as-produced CNC heterostructures were incorporated into polyvinyl alcohol (PVA) hydrogel resulting in CNC heterostructure-PVA hydrogel with ˜ 75% water absorbing capability. These novel hydrogels were also characterized by SEM and showed actuation under 0.2 T magnet. They are promising for smart analytical devices and platform.

Synthesis of CuO and Cu2O crystalline nanowires using Cu(OH)2 nanowire templates

2003 ◽  
Vol 18 (12) ◽  
pp. 2756-2759 ◽  
Author(s):  
Wenzhong Wang ◽  
Oomman K. Varghese ◽  
Chuanmin Ruan ◽  
Maggie Paulose ◽  
Craig A. Grimes
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Average Diameter ◽  
Structural Features ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthesis Conditions ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron

Crystalline CuO and Cu2O nanowires with an average diameter of about 10 nm and lengths of several tens of microns were successfully synthesized, depending on synthesis conditions, using precursor Cu(OH)2 nanowires as templates. The crystallinity, purity, morphology, and structural features of the as-prepared nanowires were characterized by powder x-ray diffraction, selected-area electron diffraction, and high-resolution transmission electron microscopy. The results showed that the precursor polycrystalline Cu(OH)2 nanowires served as both reactants for the growth of CuO and Cu2O nanowires, and as templates controlling the size and shape of the resulting nanowires.

scholarly journals Coprecipitation Method of Synthesis, Characterization, and Cytotoxicity of Pr3+:LaF3 (CPr = 3, 7, 12, 20, 30%) Nanoparticles

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Maksim S. Pudovkin ◽  
Pavel V. Zelenikhin ◽  
Victoria Shtyreva ◽  
Oleg A. Morozov ◽  
Darya A. Koryakovtseva ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Light Scattering ◽  
High Resolution ◽  
Dynamic Light Scattering ◽  
Hydrodynamic Radius ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

The Pr3+:LaF3 (CPr = 3, 7, 12, 20, 30%) nanoparticles were characterized by means of high-resolution transmission electron microscopy, X-ray diffraction, optical spectroscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, and MTT assay. It was revealed that the average diameter of all the NPs is around 14–18 nm. The hydrodynamic radius of the Pr3+:LaF3 (CPr = 7%) nanoparticles strongly depends on the medium. It was revealed that hydrodynamic radii of the Pr3+:LaF3 (CPr = 7%) nanoparticles in water, DMEM, and RPMI-1640 biological mediums were 18 ± 5, 41 ± 6, and 186 ± 8 nm, respectively. The Pr3+:LaF3 (CPr = 7%) nanoparticles were nontoxic at micromolar concentrations toward COLO-320 cell line. The lifetime curves were fitted biexponentially, and for the Pr3+:LaF3 (CPr = 7%) NPs, the luminescence lifetimes of Pr3+ ions were 480 ± 2 and 53 ± 5 nanosec.

A Preparation of High Resolution Standards for Electron Microscopy. Part II

1971 ◽  
Vol 29 ◽  
pp. 160-161
Author(s):  
Akira Tanaka ◽  
David F. Harling
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Single Crystal ◽  
Dark Field ◽  
Graphitized Carbon Black ◽  
Graphitized Carbon ◽  
Dark Field Imaging ◽  
Crystal Films ◽  
Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

Structural analysis of the surface-layer protein of spirillum serpens by high-resolution electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 738-739
Author(s):  
W. H. Wu ◽  
R. M. Glaeser
Keyword(s):  
Electron Microscopy ◽  
Surface Layer ◽  
Structural Analysis ◽  
High Resolution ◽  
Low Dose ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
Surface Layer Protein ◽  
Morphological Unit ◽  
Resolution Electron

Spirillum serpens possesses a surface layer protein which exhibits a regular hexagonal packing of the morphological subunits. A morphological model of the structure of the protein has been proposed at a resolution of about 25 Å, in which the morphological unit might be described as having the appearance of a flared-out, hollow cylinder with six ÅspokesÅ at the flared end. In order to understand the detailed association of the macromolecules, it is necessary to do a high resolution structural analysis. Large, single layered arrays of the surface layer protein have been obtained for this purpose by means of extensive heating in high CaCl2, a procedure derived from that of Buckmire and Murray. Low dose, low temperature electron microscopy has been applied to the large arrays.As a first step, the samples were negatively stained with neutralized phosphotungstic acid, and the specimens were imaged at 40,000 magnification by use of a high resolution cold stage on a JE0L 100B. Low dose images were recorded with exposures of 7-9 electrons/Å2. The micrographs obtained (Fig. 1) were examined by use of optical diffraction (Fig. 2) to tell what areas were especially well ordered.

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