THE INFLUENCE OF THE SUPERCOOLING ON THE MECHANICAL PROPERTIES AND CRYSTAL MORPHOLOGY OF WAXY OILS

2016 ◽  
Author(s):  
Diogo Andrade ◽  
Talita Janaina Heller ◽  
Moisés Marcelino Neto ◽  
Cezar Otaviano Ribeiro Negrao
Keyword(s):  
Mechanical Properties ◽  
Crystal Morphology

scholarly journals Fluconazole-tartaric acid co-crystal formation and its mechanical properties

2021 ◽  
pp. 116-122
Author(s):  
Fikri Alatas ◽  
Nia Suwartiningsih ◽  
Hestiary Ratih ◽  
Titta Hartyana Sutarna
Keyword(s):  
Mechanical Properties ◽  
Tartaric Acid ◽  
Crystal Morphology ◽  
Active Pharmaceutical Ingredient ◽  
Raw Material ◽  
Molar Ratio ◽  
Crystal Formation ◽  
Polarization Microscopy ◽  
Scanning Calorimetry ◽  
Pxrd Pattern

Introduction: The formation of co-crystal is widely studied to obtain more favourable physicochemical properties than the pure active pharmaceutical ingredient (API). The co-crystal formation between an anti-fungal drug, fluconazole (FLU), and tartaric acid (TAR) has been investigated and its impact on mechanical properties has also been studied. Methods: The co-crystal of FLU-TAR (1:1) molar ratio was prepared by ultrasound-assisted solution co-crystallization (USSC) method with ethanol as the solvent. Polarization microscopy was used to observe the crystal morphology. Meanwhile, powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) methods were used to characterise the co-crystal formation. The mechanical properties of the co-crystal, such as flowability and tablet-ability, were compared with pure FLU. Results: Photomicroscopes revealed the unique crystal morphology of the USSC product was different from the two starting components. The typical PXRD pattern was shown by the USSC product, which indicated the formation of FLU-TAR co-crystal. In addition, the DSC thermogram revealed 169.2°C as the melting point of the FLU-TAR co-crystal, which is between the melting points of FLU and TAR. It indicates that FLU-TAR co-crystal has better flowability and tablet-ability than pure FLU. Conclusion: FLU-TAR co-crystal is one of the alternative solid forms for a raw material in pharmaceutical tablet preparation because it has better mechanical properties than pure fluconazole.

Polyethylene/sepiolite fibers. Influence of drawing and nanofiller content on the crystal morphology and mechanical properties

2014 ◽  
Vol 55 (5) ◽  
pp. 1096-1103 ◽  
Author(s):  
Yanela Alonso ◽  
Raquel E. Martini ◽  
Antonio Iannoni ◽  
Andrea Terenzi ◽  
José M. Kenny ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Crystal Morphology ◽  
Nanofiller Content ◽  
Morphology And Mechanical Properties

Effect of Uniaxial Deformation, Annealing and Carbon Nanotubes on the Morphology and Mechanical Properties of Poly (Butylene Terephthalate) and PBT Nanocomposites

2007 ◽  
Author(s):  
Gaurav Mago ◽  
Jerry A. Dutreuil ◽  
Frank T. Fisher ◽  
Dilhan M. Kalyon
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Crystal Morphology ◽  
Polarized Light ◽  
Uniaxial Deformation ◽  
Multi Walled Carbon Nanotubes ◽  
Strain Induced Crystallization ◽  
Walled Carbon Nanotubes ◽  
Induced Crystallization ◽  
Morphology And Mechanical Properties

The goal of this investigation is to elucidate the interrelations between the strain-induced crystallization behavior, morphology and mechanical properties of poly (butylene terephthalate) PBT and its nanocomposites with multi-walled carbon nanotubes (MWNTs). The mechanical properties of semicrystalline polymers such as PBT depend upon the processing conditions, which affect the crystallization behavior and the resulting crystal morphology developed within the processed sample. PBT is observed to undergo strain-induced crystallization during uniaxial deformation, with concomitant changes in the polymer crystal as a function of the applied strain history. In the current work polymer morphology was investigated with wide angle XRD, differential scanning calorimetry (DSC) and polarized light microscopy (PLM). DSC results indicate an increase in crystallinity due to strain-induced crystallization during uniaxial cold-stretching, which was further confirmed with XRD analysis of the samples. Analyses of the samples under polarized light pre- and post-stretching clearly show that there is a transformation of the spherulitic crystals of the pre-stretch morphology into elongated oblong crystals, as the imposed strain exceeds a critical value. Annealing of PBT was done under different conditions to probe the effects of changes in the crystallinity obtained upon thermal treatment on polymer morphology and mechanical properties. The annealed samples were found to have high crystallinity, high Young’s modulus, and low yield stress values as compared to unannealed samples processed under similar conditions. To investigate the effects of nanoparticle loadings on PBT crystal morphology and mechanical properties, pure PBT was melt mixed with different concentrations of multi-walled carbon nanotubes (MWNTs). Due to the increased nucleation rate effect associated with the incorporation of MWNTs, the PBT crystallization temperature was increased and the crystal size decreased with the increasing concentration of MWNTs. Tensile tests performed on PBT and their nanocomposite samples revealed decreases in the elongation at break values. Research is ongoing to understand the relationship between the MWNT loading levels and mechanical properties along with study of orientation of MWNTs under tensile load and its effect on strain-induced crystallization.

Effect of Interlayers on the Structure and Properties of TiAlSiN Coatings Deposited on High-Speed Steel Substrate

2013 ◽  
Vol 842 ◽  
pp. 302-306
Author(s):  
Hao Du ◽  
Hai Bo Zhao ◽  
Ji Xiong ◽  
Lin Lin Wang ◽  
Guang Xian
Keyword(s):  
Mechanical Properties ◽  
High Speed ◽  
Crystal Morphology ◽  
Steel Substrate ◽  
High Speed Steel ◽  
Structure And Properties ◽  
Predominant Orientation ◽  
Tialsin Coating ◽  
Morphology And Mechanical Properties ◽  
Coating Growth

TiAlSiN coatings with Ti or Cr interlayers were deposited on high-speed steel using magnetron sputtering methods. The structure, crystal morphology and mechanical properties were investigated systematically. The results show that (200) is the dominant preferred orientation in Ti/TiAlSiN coating, while (111) become the predominant orientation of the deposited Cr/TiAlSiN coating, which is related to the surface energy. Due to the changes of the coating growth style, the Cr/TiAlSiN coating shows columnar crystals morphology. The Ti/TiAlSiN coating performs better adhesion and H/E ratio, which is proved to have better wear resistance. But the specimens with Cr interlayer have better hardness and elastic modulus, which is due to the growth style of the crystals.

Study on Self-Reinforcement of High-Density Polyethylene Extruded with Vibration in Low Temperature

2011 ◽  
Vol 337 ◽  
pp. 368-371
Author(s):  
Xue Mei Qin ◽  
Bao Shan Shi ◽  
Bing Li
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
High Density Polyethylene ◽  
Crystal Morphology ◽  
High Density ◽  
Axial Vibration ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Scanning Electron Microcopy

The effect of vibration on the microstructure and mechanical properties of high-density polyethylene (HDPE) sheets, obtained through vibration plasticating extruder in low temperature, were studied systematically. Property Tests show that the tensile strength and the Vika temperature were much improved under the reciprocating axial vibration in low temperature. Differential scanning calorimetry , scanning electron microcopy and wide angle X-ray diffraction were executed to analyze the microstructure of the samples. The results indicate that the vibration extrudate in low temperature has higher crystallinity, perfect crystallite, and new crystal morphology formed , which account for enhancement of the mechanical properties and Vika temperature of sheets, compared to conventional static extrudate.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

Effects of cooling rate on the mechanical properties of dual phase treated vanadium steels

1983 ◽  
Vol 41 ◽  
pp. 220-221
Author(s):  
L.J. Chen ◽  
H.C. Cheng ◽  
J.R. Gong ◽  
J.G. Yang
Keyword(s):  
Mechanical Properties ◽  
Cooling Rate ◽  
Automobile Industry ◽  
High Strength ◽  
Weight Percent ◽  
Low Alloy Steels ◽  
Dual Phase ◽  
Resource Requirement ◽  
Alloy Steels ◽  
Potential Weight

For fuel savings as well as energy and resource requirement, high strength low alloy steels (HSLA) are of particular interest to automobile industry because of the potential weight reduction which can be achieved by using thinner section of these steels to carry the same load and thus to improve the fuel mileage. Dual phase treatment has been utilized to obtain superior strength and ductility combinations compared to the HSLA of identical composition. Recently, cooling rate following heat treatment was found to be important to the tensile properties of the dual phase steels. In this paper, we report the results of the investigation of cooling rate on the microstructures and mechanical properties of several vanadium HSLA steels.The steels with composition (in weight percent) listed below were supplied by China Steel Corporation: 1. low V steel (0.11C, 0.65Si, 1.63Mn, 0.015P, 0.008S, 0.084Aℓ, 0.004V), 2. 0.059V steel (0.13C, 0.62S1, 1.59Mn, 0.012P, 0.008S, 0.065Aℓ, 0.059V), 3. 0.10V steel (0.11C, 0.58Si, 1.58Mn, 0.017P, 0.008S, 0.068Aℓ, 0.10V).

Lattice Imaging of Grain Boundaries in Ceramics

1977 ◽  
Vol 35 ◽  
pp. 114-115
Author(s):  
D. R. Clarke ◽  
G. Thomas
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Grain Boundaries ◽  
High Temperature Strength ◽  
Current Interest ◽  
Lattice Imaging ◽  
Special Significance ◽  
Structural Applications ◽  
Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Electron Microscopic ◽  
Aromatic Polyamides ◽  
Radial Arrangement ◽  
Scanning Electron ◽  
Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

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