Preparation and Mechanical Property of PLLA/Nano-SiO2 Composite

2012 ◽  
Vol 476-478 ◽  
pp. 367-370
Author(s):  
Xin Fan
Keyword(s):  
Mechanical Property ◽  
Cross Section ◽  
Bending Strength ◽  
Sio2 Content ◽  
X Ray Diffraction ◽  
Mixing Effect ◽  
X Ray ◽  
Nano Sio2 ◽  
Bending Modulus ◽  
Sio2 Powder

Blends of Poly(L-lactide) (PLLA) and nano-SiO2 powder were prepared via solution mixing. Effect of nano-SiO2 particles on the crystallinity of PLLA in composite was investigated by X-ray diffraction, the result indicated that the incorporation of nano-SiO2 did not influence the crystallinity of PLLA in composite. The bending strength and modulus of the PLLA/nano-SiO2 composites with varying nano-SiO2 content were tested, showing that the bending strength reduced with the increase of nano-SiO2 content and the bending modulus increased. The SEM graphs of PLLA/nano-SiO2 composites were illustrated that the cross-section of composites varied from brittle to ductile fracture with the content of nano-SiO2 increasing up to 10 %, and changed from ductile to brittle fracture with further increasing of nano-SiO2 content.

Study on the Propertyies of Magnesium-Doped Calcium Polyphosphate Scaffolds Ceramics

2011 ◽  
Vol 393-395 ◽  
pp. 334-337
Author(s):  
Yin Zhang ◽  
De Shuang Kong ◽  
Chang Jun Gu ◽  
Xiao Wei Han ◽  
Tai Qiu
Keyword(s):  
Cross Section ◽  
Bending Strength ◽  
Magnesium Content ◽  
Reaction Sintering ◽  
X Ray Diffraction ◽  
Solid Reaction ◽  
X Ray ◽  
Calcium Polyphosphate ◽  
The Stability ◽  
Porous Bioceramics

This Magnesium-doped calcium polyphosphate (MCPP) porous bioceramics of different magnesium content were prepared by the method of solid reaction sintering. The effect of magnesium on the structure and density of magnesium-doped calcium polyphosphate bioceramics was studied. Phases, cross section morphologies and porosity of MCPP bioceramics were analyzed with X-ray diffraction(XRD) and scanning electron microscopy (SEM). The results show that MCPP ceramics were successfully prepared by the solid reaction sintering, and the bending strength of ceramics began to increase and then to decrease with increasing amounts of magnesium content apart with the improvement of the stability improved.

Freeze-Fracture Replication of Frozen Outer Segments of Rat Retinal Rods

1969 ◽  
Vol 27 ◽  
pp. 392-393
Author(s):  
Thomas S. Leeson ◽  
C. Roland Leeson
Keyword(s):  
Electron Microscopy ◽  
Cross Section ◽  
Outer Segment ◽  
Freeze Fracture ◽  
X Ray Diffraction ◽  
X Ray ◽  
Outer Segments ◽  
Retinal Rods ◽  
Temperature Electron ◽  
Freeze Etching

Numerous previous studies of outer segments of retinal receptors have demonstrated a complex internal structure of a series of transversely orientated membranous lamellae, discs, or saccules. In cones, these lamellae probably are invaginations of the covering plasma membrane. In rods, however, they appear to be isolated and separate discs although some authors report interconnections and some continuities with the surface near the base of the outer segment, i.e. toward the inner segment. In some species, variations have been reported, such as longitudinally orientated lamellae and lamellar whorls. In cross section, the discs or saccules show one or more incisures. The saccules probably contain photolabile pigment, with resulting potentials after dipole formation during bleaching of pigment. Continuity between the lamina of rod saccules and extracellular space may be necessary for the detection of dipoles, although such continuity usually is not found by electron microscopy. Particles on the membranes have been found by low angle X-ray diffraction, by low temperature electron microscopy and by freeze-etching techniques.

Fractionation of polymethylene chains: An electron crystallographic investigation

1986 ◽  
Vol 44 ◽  
pp. 794-795
Author(s):  
Douglas L. Dorset
Keyword(s):  
Cross Section ◽  
Binary Systems ◽  
Linear Chain ◽  
Pure Component ◽  
Organic Substrates ◽  
Crystallographic Investigation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molecular Sizes ◽  
The Stability

A variety of linear chain materials exist as polydisperse systems which are difficultly purified. The stability of continuous binary solid solutions assume that the Gibbs free energy of the solution is lower than that of either crystal component, a condition which includes such factors as relative molecular sizes and shapes and perhaps the symmetry of the pure component crystal structures.Although extensive studies of n-alkane miscibility have been carried out via powder X-ray diffraction of bulk samples we have begun to examine binary systems as single crystals, taking advantage of the well-known enhanced scattering cross section of matter for electrons and also the favorable projection of a paraffin crystal structure posited by epitaxial crystallization of such samples on organic substrates such as benzoic acid.

Silicate-germanate K2Y[(Si3Ge)O10(OH)] with unusual complex corrugated layer and its correlation to ring silicate gerenite and chain silicate chkalovite

2020 ◽  
Vol 235 (4-5) ◽  
pp. 167-172
Author(s):  
Anastasiia P. Topnikova ◽  
Elena L. Belokoneva ◽  
Olga V. Dimitrova ◽  
Anatoly S. Volkov ◽  
Leokadiya V. Zorina
Keyword(s):  
Low Temperature ◽  
Cross Section ◽  
Complex Anion ◽  
Diffraction Experiment ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Chain Silicate ◽  
Novel Complex

AbstractA new silicate-germanate K2Y[(Si3Ge)O10(OH)] was synthesized hydrothermally in a system Y2O3:GeO2:SiO2 = 1:1:2 (T = 280 °C; P = 90–100 atm.); K2CO3 was added to the solution as a mineralizer. Single-crystal X-ray diffraction experiment was carried out at low temperature (150 K). The unit cell parameters are a = 10.4975(4), b = 6.9567(2), c = 15.4001(6) Å, β = 104.894(4)°; V = 1086.86(7) Å3; space group is P 21/c. A novel complex anion is presented by corrugated (Si,Ge) tetrahedral layers connected by couples of YO6 octahedra into the mixed microporous framework with the channels along b and a axes, the maximal size of cross-section is ~5.6 Å. This structure has similarity with the two minerals: ring silicate gerenite (Ca,Na)2(Y,REE)3Si6O18 · 2H2O and chain silicate chkalovite Na2BeSi2O6. Six-member rings with 1̅ symmetry as in gerenite are distinguished in the new layer. They are mutually perpendicular to each other and connected by additional tetrahedra. Straight crossing chains in chkalovite change to zigzag four-link chains in the new silicate-germanate layer.

INFLUENCE OF INTERFACE AND POLARIZATION ON MAGNETOELECTRIC COUPLING IN Ni-LEAD ZIRCONIUM TITANATE-Ni TRILAYERS DERIVED BY ELECTROLESS DEPOSITION

2012 ◽  
Vol 19 (03) ◽  
pp. 1250030
Author(s):  
K. BI ◽  
Y. G. WANG
Keyword(s):  
Cross Section ◽  
Electroless Deposition ◽  
Mechanical Deformation ◽  
Interface Roughness ◽  
Zirconium Titanate ◽  
Interface Conditions ◽  
Lead Zirconium Titanate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Voltage Coefficient

Magnetoelectric (ME) coupling in layered structures of magnetostrictive and piezoelectric phases are mediated by mechanical deformation and depends strongly on the interface conditions. Ni -lead zirconium titanate- Ni trilayers with neither electrodes nor bonding layers have been derived by electroless deposition. The structure of the electroless deposited Ni layer was characterized by X-ray diffraction. The cross-section of the Ni/PZT layers was investigated using scanning electron microscopy. The value of ME voltage coefficient (αE,31) increases as the interface roughness increases. The maximum of αE,31 for the Ni/PZT/Ni trilayers polarized after electroless deposition is higher than that for the Ni/PZT/Ni trilayers polarized before electroless deposition. It is essential to optimize the interface and the polarization to obtain higher ME voltage coefficient.

Laser Sintering of Greens Compacts of MoSi2

2006 ◽  
Vol 530-531 ◽  
pp. 364-368
Author(s):  
G. de Vasconcelos ◽  
R. Cesar Maia ◽  
Carlos Alberto Alves Cairo ◽  
R. Riva ◽  
N.A.S. Rodrigues ◽  
...  
Keyword(s):  
Cross Section ◽  
Laser Processing ◽  
Single Phase ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heating Source ◽  
Scanning Electron Microcopy ◽  
Conventional Sintering ◽  
Reduced Time

In this study, the results of the feasibility of sintering green compacts of metallic powder of MoSi2 by a CO2 laser beam as the heating source has been investigated. The main advantage of this technique is to promote a dense material in a reduced time when compared to the conventional sintering process. In order to sintering the MoSi2 powder, green compacts of 6mm of diameter and 1.6mm thickness were produced in a steel die in a uniaxial press at 100MPa and after, isostatic pressed at 350MPa. The micrograph of the samples exposed to the laser radiation performed by scanning electron microcopy (SEM) reveal the efficiency of the sintering process and the X-ray diffraction of the powders confirmed the presence of single phase after and before laser processing. The average microhardness of these compacts reached near to 700 Hv0.2 in the cross section to the laser irradiation, indicating the all sintering of the green compact.

Structure Characterization of Sintered CaO-Al2O3-SiO2 Glass-Ceramic Reinforced with Spodumene

2013 ◽  
Vol 834-836 ◽  
pp. 309-314
Author(s):  
Zi Fan Xiao ◽  
Jin Shu Cheng ◽  
Jun Xie
Keyword(s):  
Glass Ceramic ◽  
Energy Dispersive Spectrometry ◽  
Crystal Size ◽  
Bending Strength ◽  
Glass Ceramics ◽  
Structure Characterization ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

A glass-ceramic belonging to the CaO-Al2O3-SiO2(CAS) system with different composition of spodumene and doping the Li2O with amount between 0~2.5 % (mass fraction) were prepared by onestage heat treatment, under sintering and crystallization temperature at 1120 °C for two hours. In this paper, differential thermal analysis, X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry and bending strength test were employed to investigate the microstructure and properties of all samples. β-wollastonite crystals were identified as the major crystalline phases, and increasing Li2O was found to be benefit for the crystallization and tiny crystalline phases remelting, resulting in the content of major crystalline phases increased first and then decreased with increasing the expense of spodumene. Meanwhile, the crystal size can be positively related with the content of Li2O. The preferable admixed dosage of spodumene can be obtained, besides the strength of glass-ceramics can be more than 90 MPa.

scholarly journals Fabrication of Silk Resin with High Bending Properties by Hot-Pressing and Subsequent Hot-Rolling

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2716
Author(s):  
Hoang Anh Tuan ◽  
Shinji Hirai ◽  
Shota Inoue ◽  
Alharbi A. H. Mohammed ◽  
Shota Akioka ◽  
...  
Keyword(s):  
Hot Rolling ◽  
Hot Pressing ◽  
Bending Strength ◽  
Decomposition Temperature ◽  
Attenuated Total Reflectance ◽  
X Ray Diffraction ◽  
Bending Properties ◽  
X Ray ◽  
Bombyx Mori Silk ◽  
Increased Strength

This research reports the processability and mechanical properties of silk resins prepared by hot-pressing followed by hot-rolling and then analyzes their thermal and structural properties. The results show that regenerated silk (RS) resins are better suited for hot-rolling than Eri and Bombyx mori silk resins (untreated silk). When hot-rolling at 160 °C with a 50% of reduction ratio, maximum bending strength and Young’s modulus of RS resin reaches 192 MPa and 10.2 GPa, respectively, after pretreatment by immersion in 40 vol% ethanol, and 229 MPa and 12.5 GPa, respectively, after pretreatment by immersion in boiling water. Increased strength of the material is attributed to the increased content of aggregated strands and intramolecular linking of β sheets (attenuated total reflectance Fourier-transform infrared spectroscopy) and higher crystallinity (X-ray diffraction analysis). After hot-pressing and hot-rolling, RS resins have a stable decomposition temperature (297 °C).

Relationship Between Microstructure and Hardness of ZrN/TiN Multi-Layers with Various Bilayer Thicknesses

2010 ◽  
Vol 63 ◽  
pp. 392-395
Author(s):  
Yoshifumi Aoi ◽  
Satoru Furuhata ◽  
Hiromi Nakano
Keyword(s):  
Mechanical Property ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Beam Sputtering ◽  
Microstructure And Mechanical Property

ZrN/TiN multi-layers were synthesized by ion beam sputtering technique. Microstructure and mechanical property of the ZrN/TiN multi-layers were characterized and the relationships between microstructure and hardness of the ZrN/TiN multi-layers with various bilayer thicknesses and thickness ratios were investigated. The microstructure of multi-layers have been investigated using transmission electron microscope (TEM) and X-ray diffraction (XRD).

InAs Quantum Dots Grown on an AlGaAsSb Strain-Relief Buffer

2000 ◽  
Vol 642 ◽  
Author(s):  
A.L. Gray ◽  
L. R. Dawson ◽  
Y. Lin ◽  
A. Stintz ◽  
Y.-C. Xin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Cross Section ◽  
Gaas Substrate ◽  
Buffer Layers ◽  
Threading Dislocations ◽  
X Ray Diffraction ◽  
Strain Relief ◽  
Inas Quantum Dots ◽  
X Ray ◽  
Transmission Electron

ABSTRACTAn In(Ga)As-based self-assembled quantum dot laser test structure grown on strain-relief Al0.5Ga0.5As1-ySby strain-relief buffer layers (0≤y ≤ 0.24) on a GaAs substrate is investigated in an effort to increase dot size and therefore extend the emission wavelength over conventional InAs quantum dots on GaAs platforms. Cross-section transmission electron microscopy, and high-resolution x-ray diffraction are used to monitor the dislocation filtering process and morphology in the buffer layers. Results show that the buffer layers act as an efficient dislocation filter by drastically reducing threading dislocations, thus providing a relaxed, low dislocation, compositionally modulated Al0.5Ga0.5Sb0.24As0.76 substrate for large (500Å height x 300Å width) defect -free InAs quantum dots. Photoluminescence shows a ground-state emission of the InAs quantum dots at 1.45 μm.

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