Study on Thermal Conductivity of Multilayer Graphene/NR Composite

2014 ◽  
Vol 933 ◽  
pp. 3-7 ◽  
Author(s):  
Gui Long Wu ◽  
Long Liu ◽  
Xiao Zong ◽  
Yan He ◽  
Ze Peng Wang
Keyword(s):  
Thermal Conductivity ◽  
Differential Scanning Calorimetry ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Mass Fraction ◽  
Structure Change ◽  
Multilayer Graphene ◽  
Scanning Calorimetry ◽  
Structure And Morphology ◽  
Transmission Electron

Graphene/NR composite was prepared in emulsion blending and the multilayer graphene was about 4-8 layers. Different mass fraction of this kind of graphene was mixed into NR in this work.The thermal conductivity of this compositive system was respected to be improved apparently since the high thermal conductivity of graphene. In this work, TEM(Transmission electron microscope) was used to observe the structure and morphology of the multilayer graphene. NETZSCH LFA was used to research the change of thermal conductivity with the fraction of grahene changing. DSC(differential scanning calorimetry) was used to research the structure change in the series of composites. The TEM results showed that the graphene we used is 4-5 layers. LFA had proved that the multilayer graphene has affected the thermal conductivity of matrix greatly and DSC also provided evidence to support the same views.

Template Induced Synthesis of Nano-Hydroxyapatite by Co-Precipitation Method

2011 ◽  
Vol 311-313 ◽  
pp. 1713-1716 ◽  
Author(s):  
Yan Rong Sun ◽  
Tao Fan ◽  
Chang An Wang ◽  
Li Guo Ma ◽  
Feng Liu
Keyword(s):  
Electron Microscope ◽  
Chondroitin Sulfate ◽  
Aspartic Acid ◽  
Transmission Electron Microscope ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure And Morphology ◽  
Transmission Electron ◽  
Co Precipitation

Nano-hydroxyapatite with different morphology was synthesized by the co-precipitation method coupled with biomineralization using Ca(NO3)2•4H2O and (NH4)2HPO4 as reagents, adding chondroitin sulfate, agarose and aspartic acid as template. The structure and morphology of the prepared powders were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM).

scholarly journals Synthesis of BaTiO3 Nanoparticles via Hydrothermal Method

2017 ◽  
Vol 268 ◽  
pp. 172-176 ◽  
Author(s):  
Nurul Norfarina Hasbullah ◽  
Oon Jew Lee ◽  
Josephine Liew Ying Chyi ◽  
Soo Kien Chen ◽  
Zainal Abidin Talib
Keyword(s):  
Electron Microscope ◽  
Hydrothermal Method ◽  
Transmission Electron Microscope ◽  
Hydrothermal Process ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Tga And Dsc

In this work, BaTiO3 nanoparticles were synthesized through hydrothermal method. The powder obtained from the hydrothermal process (as-synthesized powder) was calcined at 1000 °C. The phase formation and morphology of the as-synthesized and calcined powders were studied using X-ray diffraction (XRD), thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyzer, and transmission electron microscope (TEM). The XRD data showed that the as-synthesized powder is partially amorphous. Upon calcining the powder at 1000 °C, highly crystalline BaTiO3 with tetragonal structure was obtained. As shown by TGA and DSC analysis, the precursor powder was completely transformed into BaTiO3 at 1000 °C. The presence of BaCO3 as an impurity phase in the powder is due to the lack of Ba2+ / Ti3+/4+. Transmission electron microscope images showed that the particle size of the as-synthesized powder increased after calcination due to crystal growth. In addition, nanocubes with the average size of around 11.66 nm were obtained as a result of the calcination compared to the ellipsoid like particles of the as-synthesized powder.

Study on the Activation Energy of Nanocrystallization of Amorphous Fe78Si9B13 Alloy Treated by Low Frequency Pulse Magnetic Field

2011 ◽  
Vol 299-300 ◽  
pp. 584-587 ◽  
Author(s):  
Ying Chun Zhou ◽  
Qi Jian Zhang
Keyword(s):  
Magnetic Field ◽  
Activation Energy ◽  
Differential Scanning Calorimetry ◽  
Electron Microscope ◽  
Single Phase ◽  
Pulse Magnetic Field ◽  
Low Frequency ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Frequency Pulse

The amorphous Fe78Si9B13 alloy was treated by low frequency pulse magnetic field (LFPMF). The microstructure was observed by Mössbauer spectroscopy and Transmission Electron Microscope. The activation energy of nanocrystallization of amorphous alloy Fe78Si9B13 treated by low frequency pulse magnetic field was determined by differential scanning calorimetry (DSC). The results indicated that the activation energy was decreased from 433.6kJ.mol-1 to less than 200kJ.mol-1 after LFPMF. The nucleating rate of α-Fe(Si) was increased and there was only single phase α-Fe(Si) crystalline formed.

Effects of Hydrogen on Machinability of BT25y Alloy

2010 ◽  
Vol 148-149 ◽  
pp. 385-388
Author(s):  
Xiao Zhen Hua ◽  
Xin Yuan Peng ◽  
Xian Liang Zhou ◽  
Qing Jun Chen
Keyword(s):  
Thermal Conductivity ◽  
Surface Roughness ◽  
Phase Composition ◽  
Electron Microscope ◽  
Cutting Force ◽  
Grain Refinement ◽  
Hydrogen Concentration ◽  
Transmission Electron Microscope ◽  
X Ray ◽  
Transmission Electron

Effects of hydrogen on machinability involving cutting force, surface roughness and chips morphology of BT25y alloy with semi finish machining were carried out. The microstructures and phase composition of different concentrations were studyed by metallurgical microscopy, transmission electron microscope (TEM), and X-ray diffractions (XRD). The results show that existing a optimum hydrogen concentration (0.20wt.%) for machinability of BT25y alloy in which cutting force decreases 179N and surface roughness reduces about 24%, in addition, chips morphology are transferred from continuous to segmental. The grain refinement, hydride precipitations and thermal conductivity resulting from hydrogen can improve the machinability of BT25y alloy.

A Reproducible Selective Stain for Cardiac Sarcoplasmic Reticulum

1974 ◽  
Vol 32 ◽  
pp. 214-215
Author(s):  
R. A. Waugh ◽  
J. R. Sommer
Keyword(s):  
Complex System ◽  
Electron Microscope ◽  
Sarcoplasmic Reticulum ◽  
Transmission Electron Microscope ◽  
Electron Microscopic ◽  
Cardiac Sarcoplasmic Reticulum ◽  
Transmission Electron

Cardiac sarcoplasmic reticulum (SR) is a complex system of intracellular tubules that, due to their small size and juxtaposition to such electron-dense structures as mitochondria and myofibrils, are often inconspicuous in conventionally prepared electron microscopic material. This study reports a method with which the SR is selectively “stained” which facilitates visualizationwith the transmission electron microscope.

Surface Structure of the Spores of Glugea Weissenbergi

1969 ◽  
Vol 27 ◽  
pp. 238-239
Author(s):  
Sanford H. Vernick ◽  
Anastasios Tousimis ◽  
Victor Sprague
Keyword(s):  
Electron Microscope ◽  
Surface Structure ◽  
Transmission Electron Microscope ◽  
Mature Spore ◽  
Spore Surface ◽  
Sectioned Material ◽  
Transmission Electron ◽  
Surface Detail

Recent electron microscope studies have greatly expanded our knowledge of the structure of the Microsporida, particularly of the developing and mature spore. Since these studies involved mainly sectioned material, they have revealed much internal detail of the spores but relatively little surface detail. This report concerns observations on the spore surface by means of the transmission electron microscope.

A New High Resolution Transmission Electron Microscope with Second-Zone Objective Lens

1969 ◽  
Vol 27 ◽  
pp. 176-177 ◽  
Author(s):  
H. Tochigi ◽  
H. Uchida ◽  
S. Shirai ◽  
K. Akashi ◽  
D. J. Evins ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Transmission Electron Microscope ◽  
Objective Lens ◽  
High Excitation ◽  
Transmission Electron ◽  
New Instrument

A New High Excitation Objective Lens (Second-Zone Objective Lens) was discussed at Twenty-Sixth Annual EMSA Meeting. A new commercially available Transmission Electron Microscope incorporating this new lens has been completed.Major advantages of the new instrument allow an extremely small beam to be produced on the specimen plane which minimizes specimen beam damages, reduces contamination and drift.

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

Aspects of microanalysis in a transmission electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 510-511
Author(s):  
R. Sinclair ◽  
B.E. Jacobson
Keyword(s):  
Grain Size ◽  
Electron Beam ◽  
Electron Microscope ◽  
Chemical Analysis ◽  
Transmission Electron Microscope ◽  
Vapor Deposition ◽  
Critical Currents ◽  
X Ray ◽  
Fine Grain ◽  
Transmission Electron

INTRODUCTIONThe prospect of performing chemical analysis of thin specimens at any desired level of resolution is particularly appealing to the materials scientist. Commercial TEM-based systems are now available which virtually provide this capability. The purpose of this contribution is to illustrate its application to problems which would have been intractable until recently, pointing out some current limitations.X-RAY ANALYSISIn an attempt to fabricate superconducting materials with high critical currents and temperature, thin Nb3Sn films have been prepared by electron beam vapor deposition [1]. Fine-grain size material is desirable which may be achieved by codeposition with small amounts of Al2O3 . Figure 1 shows the STEM microstructure, with large (∽ 200 Å dia) voids present at the grain boundaries. Higher quality TEM micrographs (e.g. fig. 2) reveal the presence of small voids within the grains which are absent in pure Nb3Sn prepared under identical conditions. The X-ray spectrum from large (∽ lμ dia) or small (∽100 Ǻ dia) areas within the grains indicates only small amounts of A1 (fig.3).

The direct determination of magnetic domain wall profiles using a split detector STEM

1978 ◽  
Vol 36 (1) ◽  
pp. 466-467
Author(s):  
J.N. Chapman ◽  
P.E. Batson ◽  
E.M. Waddell ◽  
R.P. Ferrier
Keyword(s):  
Electron Microscope ◽  
Domain Wall ◽  
Transmission Electron Microscope ◽  
Domain Walls ◽  
Photographic Plate ◽  
Magnetic Domain ◽  
Direct Determination ◽  
Quantitative Information ◽  
Scanning Transmission Electron Microscope ◽  
Transmission Electron

By far the most commonly used mode of Lorentz microscopy in the examination of ferromagnetic thin films is the Fresnel or defocus mode. Use of this mode in the conventional transmission electron microscope (CTEM) is straightforward and immediately reveals the existence of all domain walls present. However, if such quantitative information as the domain wall profile is required, the technique suffers from several disadvantages. These include the inability to directly observe fine image detail on the viewing screen because of the stringent illumination coherence requirements, the difficulty of accurately translating part of a photographic plate into quantitative electron intensity data, and, perhaps most severe, the difficulty of interpreting this data. One solution to the first-named problem is to use a CTEM equipped with a field emission gun (FEG) (Inoue, Harada and Yamamoto 1977) whilst a second is to use the equivalent mode of image formation in a scanning transmission electron microscope (STEM) (Chapman, Batson, Waddell, Ferrier and Craven 1977), a technique which largely overcomes the second-named problem as well.

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