Carbon Coated Nanoparticle Composites Synthesized in an RF Plasma Torch

ABSTRACTFeCo alloy nanoparticles are synthesized in an RF plasma torch reactor and characterized using X-ray powder diffraction (XRD) and transmission electron microscopy (XRD). Bare, uncoated particles exhibit a chain-like agglomeration morphology marked by large ring- and bridge-like structures surrounding open voids. Acetylene was used to generate large numbers of carbon-coated nanoparticles similar to those produced in carbon arc reactors. Conventional TEM of this powder revealed numerous particles below 50 nm in diameter embedded in a carbonaceous matrix. These results establish RF plasma torch processing as a well-characterized, scalable alternative to carbon arc synthesis of encapsulated nanoparticles.

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Morphology of Nanoparticles and Fullerene Blacks Produced in A Carbon Arc

MRS Proceedings ◽

10.1557/proc-359-41 ◽

1994 ◽

Vol 359 ◽

Author(s):

John Henry J. Scott ◽

S. A. Majetich ◽

S. Derrington

Keyword(s):

Inner Core ◽

Crystallographic Structure ◽

Cathode Deposit ◽

X Ray ◽

The Core ◽

Coated Nanoparticles ◽

Transmission Electron ◽

Carbon Coated ◽

Carbon Arc ◽

Graphite Rods

ABSTRACTUsing X-ray powder diffraction and transmission electron microscopy we examine the morphology and crystallographic structure of carbon-coated nanoparticles produced in a modified Huffman-Kratschmer carbon arc process. Graphite rods containing Ho were consumed in the arc and soots sampled from both the reactor walls and the inner core of the cathode deposit are compared. The inner core soot displays increased crystallinity and less amorphous carbon than wall-deposited soot, and nanoparticles in the inner core have more graphitic layers in the encapsulating shells, more gaps between the carbon coating and the core, and exhibit a greater degree of facetting than particles harvested from the reactor walls. These differences are interpreted as manifestations of the high temperature post-formation environment of the inner core of the cathode deposit.

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Cryomicroscopy of multiphase latices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089615 ◽

1991 ◽

Vol 49 ◽

pp. 1060-1061

Author(s):

O. L. Shaffer ◽

M.S. El-Aasser ◽

C. L. Zhao ◽

M. A. Winnik ◽

R. R. Shivers

Keyword(s):

Electron Microscopy ◽

Radiation Damage ◽

Freeze Fracture ◽

Particle Morphology ◽

Second Stage ◽

Transmission Electron ◽

Important Approach ◽

Carbon Coated ◽

Preparation Techniques

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

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Carbon-coated magnetic particles increase tissue temperatures after laser irradiation

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545815500182 ◽

2015 ◽

Vol 08 (05) ◽

pp. 1550018 ◽

Cited By ~ 1

Author(s):

Shupeng Liu ◽

Na Chen ◽

Fufei Pang ◽

Zhengyi Chen ◽

Tingyun Wang

Keyword(s):

Laser Irradiation ◽

Magnetic Particles ◽

Laser Energy ◽

Thermal Therapy ◽

Vibrating Sample Magnetometer ◽

X Ray Diffraction ◽

X Ray ◽

Fbg Sensor ◽

Transmission Electron ◽

Carbon Coated

Purpose: This work focused on the investigation the hyperthermia performance of the carbon-coated magnetic particles (CCMPs) in laser-induced hyperthermia. Materials and methods: We prepared CCMPs using the organic carbonization method, and then characterized them with transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectrophotometry, vibrating sample magnetometer (VSM) and X-ray diffraction (XRD). In order to evaluate their performance in hyperthermia, the CCMPs were tested in laser-induced thermal therapy (LITT) experiments, in which we employed a fully distributed fiber Bragg grating (FBG) sensor to profile the tissue's dynamic temperature change under laser irradiation in real time. Results: The sizes of prepared CCMPs were about several micrometers, and the LITT results show that the tissue injected with the CCMPs absorbed more laser energy, and its temperature increased faster than the contrast tissue without CCMPs. Conclusions: The CCMPs may be of great help in hyperthermia applications.

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Carbon-coated titania nanostructured particles: Continuous, one-step flame-synthesis

Journal of Materials Research ◽

10.1557/jmr.2003.0373 ◽

2003 ◽

Vol 18 (11) ◽

pp. 2670-2676 ◽

Cited By ~ 23

Author(s):

Hendrik K. Kammler ◽

Sotiris E. Pratsinis

Keyword(s):

Crystal Size ◽

Nitrogen Adsorption ◽

Titanium Tetraisopropoxide ◽

X Ray Diffraction ◽

Composite Powders ◽

Nanostructured Particles ◽

Carbon Particles ◽

Transmission Electron ◽

Carbon Coated ◽

One Step

Concurrent synthesis of titania-carbon nanoparticles (up to 52 wt.% in C) was studied in a diffusion flame aerosol reactor by combustion of titanium tetraisopropoxide and acetylene. These graphitically layered carbon-coated titania particles were characterized by high-resolution transmission electron microscopy (HRTEM), with elemental mapping of C and Ti, x-ray diffraction (XRD), and nitrogen adsorption [Brunauer-Emmett-Teller (BET)]. The specific surface area of the powder was controlled by the acetylene flow rate from 29 to 62 m2/g as the rutile content decreased from 68 to 17 wt.%. Light blue titania suboxides formed at low acetylene flow rates. The average XRD crystal size of TiO2 decreased steadily with increasing carbon content of the composite powders, while the average BET primary particle size calculated from nitrogen adsorption decreased first and then approached a constant value. The latter is attributed to the formation of individual carbon particles next to carbon-coated titania particles as observed by HRTEM and electron spectroscopic imaging.

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Microstructural Evolution of AI/Ni and Ni/AI Bilayer Thin Films

MRS Proceedings ◽

10.1557/proc-202-685 ◽

1990 ◽

Vol 202 ◽

Cited By ~ 2

Author(s):

J. A. Barnard ◽

E. Haftek ◽

A. Waknis ◽

M. Tan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Electron Diffraction ◽

Microstructural Evolution ◽

Interplanar Spacing ◽

Dc Magnetron Sputtering ◽

Varying Thickness ◽

Transmission Electron ◽

Reverse Sequence ◽

Carbon Coated

ABSTRACTThe growth and microstructural evolution of Al/Ni and Ni/AI bilayer thin films have been investigated as a function of Al and Ni layer thickness and thermal treatment by transmission electron microscopy. Studies were also made of Al and Ni single layers of varying thickness. All films were grown by dc magnetron sputtering using carbon coated Cu TEM grids as substrates. For the bilayers, the Al thickness was fixed at either 3.5 or 7.0 nm while the Ni thickness was varied systematically from 3.2 to 12.8 nm. Deposition sequence significantly influenced bilayer microstructure even in as-deposited samples. Al/Ni bilayers generally exhibited a finer microstructure than Ni/AI. In the 3.5 nm Al/Ni bilayers no conclusive electron diffraction evidence was found for elemental Al while for the reverse sequence both Al and NiAl3 diffraction rings were found. In the 7.0 nm Al/Ni bilayers diffraction rings due to Al were observed. The reverse sequence again produced both Al and NiAl3 diffraction rings. Interestingly, diffraction rings due to the Ni layers were found for all samples but were consistently measured at positions corresponding to a 2.5–3.5% increase in interplanar spacing. Annealing at 385°C produced evidence for generalized grain growth and strong accentuation of the electron diffraction rings due to the NiAl3 phase. Again, deposition significantly influenced annealed bilayer microstructure. For the Al/Ni sequence annealing produced polycrystalline N1AI3 island-like structures, while for Ni/AI bilayers, annealing promoted the growth of small NiAl3 crystals uniformly distributed in the film.

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A novel design of HA-coated nanoparticles co-encapsulating plasmid METase and 5-Fu shows enhanced application in targeting gastric cancer stem cells

Biological Chemistry ◽

10.1515/hsz-2017-0208 ◽

2018 ◽

Vol 399 (3) ◽

pp. 293-303 ◽

Cited By ~ 3

Author(s):

Weifeng Yang ◽

Houting Zhang ◽

Lin Xin

Keyword(s):

Gastric Cancer ◽

Tumor Growth ◽

Precipitation Method ◽

Inhibition Effect ◽

Coated Nanoparticles ◽

Transmission Electron ◽

Targeted Drug ◽

Gastric Cancer Stem Cells ◽

Novel Design

AbstractNanoparticles (NPs) are recognized as an attractive vehicles for cancer treatment due to their targeted drug release. Gastric cancer is an important killer disease, and its therapy methods still need improvement. The NPs were prepared using a precipitation method, and were evaluated using transmission electron microscopy (TEM). MTT and Transwell assays were used to determine cell viability and apoptosis.In vivoexperiments were performed to validate the effects of NPs on tumor growth. Methioninase (METase)/5-Fu co-encaspulated NPs showed highest ζ size and lowest ζ potential than other NPs. The migration and tumorsphere formation ability of CD44(+) was stronger than CD44(−). The effects of METase/5-Fu co-encaspulated NPs on inhibition cell growth was stronger than that of 5-Fu encaspulated NPs, while HA coated NPs showed significant target ability than that NPs without HA. METase supplementation promoted the inhibition effect of 5-Fu on thymidylate synthetase (TS), as well as cell apoptosis. Thein vivoexperiments demonstrated that HA coated NPs significantly inhibited tumor growth. It was concluded that HA-coated NPs enhance the target ability, while METase/5-Fu co-encaspulated NPs promote the inhibition effects on tumor growth in gastric cancer.

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In situ high-resolution transmission electron microscopy synthesis observation of nanostructured carbon coated LiFePO4

Journal of Power Sources ◽

10.1016/j.jpowsour.2011.04.003 ◽

2011 ◽

Vol 196 (18) ◽

pp. 7383-7394 ◽

Cited By ~ 45

Author(s):

M.L. Trudeau ◽

D. Laul ◽

R. Veillette ◽

A.M. Serventi ◽

A. Mauger ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Nanostructured Carbon ◽

Transmission Electron ◽

Carbon Coated

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Morphology and ultrastructure of oral strains of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus

Infection and Immunity ◽

10.1128/iai.30.2.588-600.1980 ◽

1980 ◽

Vol 30 (2) ◽

pp. 588-600

Author(s):

S C Holt ◽

A C Tanner ◽

S S Socransky

Keyword(s):

Electron Microscopy ◽

Ruthenium Red ◽

Actinobacillus Actinomycetemcomitans ◽

Electron Microscopic ◽

Transmission Electron ◽

Large Numbers ◽

Haemophilus Aphrophilus ◽

Ruthenium Red Staining ◽

Amorphous Surface ◽

Scanning Electron

Selected human oral and nonoral strains of the genera Actinobacillus and Haemophilus were examined by transmission and scanning electron microscopy. The strains examined were morphologically identical to recognized Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and Haemophilus paraphrophilus. By transmission electron microscopy, the cells were typically gram negative in morphology, with several strains possessing some extracellular ruthenium red-staining polymeric material. Numerous vesicular structures, morphologically identical to lipopolysaccharide vesicles, were seen to originate from and be continuous with the surface of the outer membrane. Large numbers of these vesicles were also found in the external environment. Scanning electron microscopic observations revealed that both actinobacilli and haemophili possessed surface projections and an amorphous surface material which connected and covered adjacent cells.

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