scholarly journals Study of synthesis and combustion of composite fuels based on n-decane and Al nanoparticles

2021 ◽  
Vol 2127 (1) ◽  
pp. 012011
Author(s):  
E V Barmina ◽  
M I Zhilnikova ◽  
V D Kobtsev ◽  
S A Kostritsa ◽  
S N Orlov ◽  
...  
Keyword(s):  
Mass Concentration ◽  
Diagnostic Technique ◽  
Average Diameter ◽  
Diffusion Combustion ◽  
Final Size ◽  
Al Nanoparticles ◽  
Temperature Distributions ◽  
Transmission Electron ◽  
Laser Diagnostic ◽  
Composite Fuel

Abstract The article is devoted to the analysis of a diffusion combustion of a composite fuel (formed by an addition of non-oxidized aluminum (Al) nanoparticles (NP’s) to n-decane) with oxygen. The process of obtaining Al NP’s consisted of a laser fragmentation of initially large commercially produced NP’s (so called “Alex” with mean diameter is about 450 nm) in the solution of isopropanol. A final size distribution of NP’s was determined by a CPS DC2400 measuring disk centrifuge. The morphology of NP’s was characterized with the Transmission Electron Microscope (TEM) JEM-100C. The measured average diameter of NP’s was about 40 nm. In the final step of a preparation of a composite fuel an isopropanol was exchanged on n-decane. To characterize the composite fuel, diffusion combustion was used in combination with the laser diagnostic technique CARS. Temperature distributions along the x direction were measured at two values of distances from the nozzle. It has been shown that, for the fuel consistent of 0.1% mass concentration of Al NP’s in n-decane, the temperature at the distance equaled 14 mm downstream from the nozzle exit of a burner in the vicinity of the flame front was significantly higher (by 200–300 K) than that upon burning of pure n-decane.

Laser synthesis of nanocomposite hydrocarbon fuel and CARS diagnostics of its combustion flame

2022 ◽  
Vol 52 (1) ◽  
pp. 100-104
Author(s):  
E V Barmina ◽  
V D Kobtsev ◽  
S A Kostritsa ◽  
S N Orlov ◽  
V V Smirnov ◽  
...  
Keyword(s):  
Diagnostic System ◽  
Hydrocarbon Fuel ◽  
Transmission Electron Microscopy Data ◽  
Al Nanoparticles ◽  
Electron Microscopy Data ◽  
Transmission Electron ◽  
Composite Fuel ◽  
Microscopy Data ◽  
20 Nm ◽  
Anti Stokes

Abstract We report an analysis of diffusive combustion in oxygen of a composite fuel formed by the addition of aluminium nanoparticles (NPs) to isopropanol. The process of obtaining Al NPs consisted in laser fragmentation of initially large industrial NPs using radiation of a pulsed nanosecond neodymium laser. The size distribution of Al NPs was determined using a measuring disk centrifuge. The average nanoparticle size was 20 nm, which is confirmed by transmission electron microscopy data. A diagnostic system based on coherent anti-Stokes Raman scattering (CARS) was used to experimentally study the diffusive combustion of composite fuel. The temperature distributions were measured in two mutually orthogonal directions (along the flame and in the transverse direction) in pure isopropanol and in isopropanol with the addition of 0.15 wt % of Al nanoparticles.

Aspiration cytology and transmission electron microscopy (TEM): A novel tissue-collection technique with useful diagnostic applications

1984 ◽  
Vol 42 ◽  
pp. 90-93
Author(s):  
J.A. Maksem ◽  
C. VanDyke ◽  
H.W. Carter ◽  
C.F. Galang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Diagnostic Technique ◽  
Needle Aspiration ◽  
Large Series ◽  
Aspiration Cytology ◽  
Fine Needle ◽  
Transmission Electron ◽  
Diagnostic Applications ◽  
Microscopic Slide

In the last decade fine needle aspiraration biopsy has gained recognition as a valuable diagnostic technique, and its benefits have been demonstrated in large series of patients with almost every type of tumor (1,2). The usual way to collect cellular material from needle-aspiration biopsies is to discharge the needle and syringe contents onto a microscopic slide and smear the material with another slide. The entire specimen is contained on the slides prepared at the time of biopsy. Serious technical difficulties are inherent to this method. 1) Inconsistent fixation, 2) drying artifact, 3) loss of tissue fragments, 4) inability to confirm impressions by a “second method”, and 5) retention of significant diagnostic material in the needle hub. Our technique avoids these difficulties.

scholarly journals Development of Quantum Dot (QD) Based Color Converters for Multicolor Display

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1089
Author(s):  
Muhammad T. Sajjad ◽  
Ashu K. Bansal ◽  
Francesco Antolini ◽  
Eduard Preis ◽  
Lenuta Stroea ◽  
...  
Keyword(s):  
Polymer Matrix ◽  
Cost Effective ◽  
Final Size ◽  
Force Microscopy ◽  
Morphological Studies ◽  
Color Displays ◽  
Transmission Electron ◽  
Different Temperatures ◽  
Color Conversion ◽  
Temperature Time

Many displays involve the use of color conversion layers. QDs are attractive candidates as color converters because of their easy processability, tuneable optical properties, high photoluminescence quantum yield, and good stability. Here, we show that emissive QDs with narrow emission range can be made in-situ in a polymer matrix, with properties useful for color conversion. This was achieved by blending the blue-emitting pyridine based polymer with a cadmium selenide precursor and baking their films at different temperatures. To achieve efficient color conversion, blend ratio and baking temperature/time were varied. We found that thermal decomposition of the precursor leads to highly emissive QDs whose final size and emission can be controlled using baking temperature/time. The formation of the QDs inside the polymer matrix was confirmed through morphological studies using atomic force microscopy (AFM) and transmission electron microscopy (TEM). Hence, our approach provides a cost-effective route to making highly emissive color converters for multi-color displays.

scholarly journals A New Nanocomposite Packaging Based on LASiS-Generated AgNPs for the Preservation of Apple Juice

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 760
Author(s):  
Maria Chiara Sportelli ◽  
Antonio Ancona ◽  
Annalisa Volpe ◽  
Caterina Gaudiuso ◽  
Valentina Lavicita ◽  
...  
Keyword(s):  
Metal Ion ◽  
Chemical Characterization ◽  
Average Diameter ◽  
Biological Action ◽  
Metal Species ◽  
Ion Release ◽  
Bioactive Materials ◽  
Transmission Electron ◽  
Metal Ion Release ◽  
Bulk Chemical

Designing bioactive materials, with controlled metal ion release, exerting a significant biological action and associated to low toxicity for humans, is nowadays one of the most important challenges for our community. The most looked-for nanoantimicrobials are capable of releasing metal species with defined kinetic profiles, either by slowing down or inhibiting bacterial growth and pathogenic microorganism diffusion. In this study, laser ablation synthesis in solution (LASiS) has been used to produce bioactive Ag-based nanocolloids, in isopropyl alcohol, which can be used as water-insoluble nano-reservoirs in composite materials like poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Infrared spectroscopy was used to evaluate the chemical state of pristine polymer and final composite material, thus providing useful information about synthesis processes, as well as storage and processing conditions. Transmission electron microscopy was exploited to study the morphology of nano-colloids, along with UV-Vis for bulk chemical characterization, highlighting the presence of spheroidal particles with average diameter around 12 nm. Electro-thermal atomic absorption spectroscopy was used to investigate metal ion release from Ag-modified products, showing a maximum release around 60 ppb, which ensures an efficient antimicrobial activity, being much lower than what recommended by health institutions. Analytical spectroscopy results were matched with bioactivity tests carried out on target microorganisms of food spoilage.

Antifungal Effectiveness of Nanosilver Colloid against Rose Powdery Mildew in Greenhouses

2008 ◽  
Vol 135 ◽  
pp. 15-18 ◽  
Author(s):  
Hae Sic Kim ◽  
Hyun Suk Kang ◽  
Gyo Jin Chu ◽  
Hong Sik Byun
Keyword(s):  
Electron Microscopy ◽  
Powdery Mildew ◽  
Colloidal Solution ◽  
Physical Method ◽  
Average Diameter ◽  
Optical Microscope ◽  
Size Analysis ◽  
Large Area ◽  
Transmission Electron ◽  
Antifungal Effects

The antifungal effectiveness against rose powdery mildew using antimicrobial nanosilver colloidal solution was investigated. Double-capsulized nanosilver was prepared by chemical reaction of silver ion with aid of physical method, reducing agent and stabilizers. The average diameter of nanosilver was about 1.5 nm. They were highly stable and very well dispersive in aqueous solution. The Transmission electron microscopy and UV-vis spectrometer were used for measurements of size analysis and their stability, respectively. The nanosilver colloidal solution of concentration of 5000 ppm was diluted in 10 ppm of 500 kg and sprayed at large area of 3306 m2polluted by rose powdery mildew. The white rose powdery mildew fade out above 95 % after 2 days and was not recurred for a week. The antifungal effects were observed by an optical microscope and photographs.

Characterization of Al65.0Cu32.9Co2.1 Alloy Containing Nanofibres

2012 ◽  
Vol 186 ◽  
pp. 212-215
Author(s):  
Jacek Krawczyk ◽  
Włodzimierz Bogdanowicz ◽  
Grzegorz Dercz ◽  
Wojciech Gurdziel
Keyword(s):  
Electron Microscopy ◽  
Average Diameter ◽  
Chemical Compositions ◽  
X Ray ◽  
Transmission Electron ◽  
Orthogonal Set ◽  
T Phase ◽  
Terminal Area ◽  
Scanning Electron

Microstructure of terminal area of Al65Cu32.9Co2.1ingots (numbers indicate at.%), obtained via directional solidification was studied. Scanning Electron Microscopy, Transmission Electron Microscopy and X-ray powder diffraction were applied. Point microanalysis by Scanning Electron Microscope was used for examination of chemical compositions of alloy phases. It was found that tetragonal θ phase of Al2Cu stoichiometric formula was the dominate phase (matrix). Additionally the alloy contained orthogonal set of nanofibres of Al7Cu2Co T phase with the average diameter of 50-500 nm and oval areas of hexagonal Al3(Cu,Co)2H-phase, surrounded by monoclinic AlCu η1phase rim. Inside some areas of H-phase cores of decagonal quasicrystalline D phase were observed.

Tribological Behavior of Carbon Nanotubes as an Additive on Lithium Grease

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Alaa Mohamed ◽  
T. A. Osman ◽  
A. Khattab ◽  
M. Zaki
Keyword(s):  
Carbon Nanotubes ◽  
Arc Discharge ◽  
Average Diameter ◽  
Friction Reduction ◽  
Lithium Grease ◽  
X Ray ◽  
Transmission Electron ◽  
Boundary Film ◽  
Load Carrying ◽  
Worn Surface

Carbon nanotubes (CNTs) with 10 nm average diameter and 5 μm in length were synthesized by electric arc discharge. The morphology and structure of CNTs were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray powder diffraction. The tribological properties of CNTs as an additive on lithium grease were evaluated with a four ball tester. The results show that the grease with CNTs exhibit good performance in antiwear (AW) and decrease the wear scare diameter (WSD) about 63%, decrease friction reduction about 81.5%, and increase the extreme pressure (EP) properties and load carrying capacity about 52% with only 1% wt. of CNTs added to lithium grease. The action mechanism was estimated through analysis of the worn surface with a scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The results indicate that a boundary film mainly composed of CNTs, Cr, iron oxide, and other organic compounds was formed on the worn surface during the friction process.

Monodisperse Fe3O4/Fe Core/Shell Nanoparticles with Enhanced Magnetic Property

2011 ◽  
Vol 306-307 ◽  
pp. 410-415
Author(s):  
Li Sun ◽  
Fu Tian Liu ◽  
Qi Hui Jiang ◽  
Xiu Xiu Chen ◽  
Ping Yang
Keyword(s):  
Average Diameter ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Core Shell ◽  
X Ray Diffraction ◽  
Shell Nanoparticles ◽  
X Ray ◽  
Transmission Electron ◽  
Shell Particles ◽  
Core Shell Nanoparticles

Core/shell type nanoparticles with an average diameter of 20nm were synthesized by chemical precipitation method. Firstly, Monodisperse Fe3O4 nanoparticles were synthesized by solvethermal method. FeSO4ž7H2O and NaBH4 were respectively dissolved in distilled water, then moderated Fe3O4 particles and surfactant(PVP) were ultrasonic dispersed into the FeSO4ž7H2O solution. The resulting solution was stirred 2 h at room temperature. Fe could be deposited on the surface of monodispersed Fe3O4 nanoparticles to form core-shell particles. The particles were characterized by using various experimental techniques, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), AGM and DTA. The results suggest that the saturation magnetization of the nanocomposites is 100 emu/g. The composition of the samples show monodisperse and the sides of the core/shell nanoparticles are 20-30nm. It is noted that the formation of Fe3O4/Fe nanocomposites magnetite nanoparticles possess superparamagnetic property.

Preparation of a monodisperse poly (N-phenylmaleimide–acrylonitrile–styrene) structural nanolatex for heat-resistant modification of PVC

2018 ◽  
Vol 32 (3) ◽  
pp. 409-423
Author(s):  
Jin Wang ◽  
Hua Qiu ◽  
Bo Cheng ◽  
Fan Zhang ◽  
Shuhua Qi
Keyword(s):  
Electron Microscope ◽  
Elemental Analysis ◽  
Hybrid Composite ◽  
Average Diameter ◽  
Microemulsion Polymerization ◽  
Scanning Calorimetry ◽  
Thermogravimetric Analyzer ◽  
Melt Compounding ◽  
Transmission Electron ◽  
Ftir Spectrometer

A monodisperse poly ( N-phenylmaleimide–acrylonitrile–styrene) (PNAS) nanolatex was synthesized via seed microemulsion polymerization. The obtained PNAS nanolatex was then directly used as an organic nanofiller to prepare polyvinyl chloride (PVC)/PNAS hybrid composite through water blending and melt compounding. The characteristics of PNAS nanolatex were analyzed by Fourier transform infrared (FTIR) spectrometer, elemental analysis, scanning electron microscope, transmission electron microscope (TEM), dynamic laser lighting scattering (DLS), differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). FTIR and elemental analysis confirmed the formation of PNAS copolymer with high monomers conversion; meanwhile, for the PNAS nanoparticles, the morphology of a well-defined core–shell spherical structure with average diameter ranging from 156 nm to 249 nm was observed. DSC analysis and TGA indicated that both polymers had excellent compatibility, and the corresponding heat resistance of PVC was greatly improved with the addition of PNAS. When PNAS loading was 50 wt%, the glass transition temperature value of PVC/PNAS hybrid composite was increased by 22.4°C, compared with that of pristine PVC. The mechanical properties of the PVC composite were also enhanced with the addition of PNAS.

scholarly journals The formation of self-assembled structures of C60 in solution and in the volume of an evaporating drop of a colloidal solution

2020 ◽  
Vol 60 (3) ◽  
Author(s):  
Urol Kudratovich Makhmanov ◽  
Abdulmutallib Kokhkharov ◽  
Sagdilla Bakhramov ◽  
Donats Erts
Keyword(s):  
Electron Microscopy ◽  
Colloidal Solution ◽  
Substrate Surface ◽  
Flat Glass ◽  
Dissipative System ◽  
Average Diameter ◽  
Flat Substrate ◽  
Transmission Electron ◽  
Physical Features ◽  
Self Aggregation

The results of experiments on the self-aggregation of C60 fullerene molecules both inside a two-component solvent (xylene/tetrahydrofuran) and in the volume of an evaporating drop of C60 colloidal solution on a flat substrate surface are presented. The investigations of C60 solutions using dynamic light scattering, transmission electron microscopy and UV–Vis absorption spectroscopy methods revealed the possibility of synthesis of fractal nanoaggregates with a diameter of up to ~135 nm at low concentrations of C60 in the solutions. The final geometric dimensions of C60 nanoaggregates were determined by the initial concentration of fullerene in the solvent medium. Using the scanning electron microscopy method, we have shown that in an open dissipative system – in the volume of an evaporating droplet of the colloidal solution of fullerene C60 sessile on the surface of a flat glass substrate, large quasispherical nanoaggregates with an average diameter of ~380–800 nm are formed. The physical features and regularities that characterize the processes of self-aggregation of fullerene particles in the volume of a drying drop were determined.

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