Quasi-Hamilton Principle of Quasi-Crystals Beam.

2011 ◽  
Vol 197-198 ◽  
pp. 1540-1544
Author(s):  
Zong Min Liu ◽  
Hai Yan Song ◽  
Ji Ze Mao
Keyword(s):  
Mechanical Properties ◽  
Research And Development ◽  
Structural Materials ◽  
Hamilton Principle ◽  
Phonon Field ◽  
New Class ◽  
Conservative Systems ◽  
Quasi Crystals

Quasi-crystals is not only a new structure of solids but also a new class of functional and structural materials. With the research and development of quasi-crystals, the mechanical properties of quasi-crystals get more and more attention. In the paper, quasi-Hamilton principle of quasi-crystals beam is established in non-conservative systems. And applying the quasi-Hamilton principle, all the equations of non-conservative quasi-crystals beam problem are obtained in the phonon field and the phason field respectively.

Microstructure and Mechanical Properties of The L12/L21 Two-Phase Alloys In The Quaternary Co-Al-Ni-Ti System

1994 ◽  
Vol 364 ◽  
Author(s):  
Takeo Matano ◽  
Yoshisato Kimura ◽  
Seiji Miura ◽  
Yoshinao Mishima
Keyword(s):  
Mechanical Properties ◽  
Elevated Temperature ◽  
Room Temperature ◽  
Structural Materials ◽  
Two Phase ◽  
Elevated Temperature Strength ◽  
New Class ◽  
Room Temperature Ductility ◽  
Microstructure And Mechanical Properties ◽  
Bend Ductility

AbstractAn attempt is made to develop a two-phase alloy consisting of the Ll2 and L21(Heusler) phases in the Co–Al–Ni–Ti quaternary sytem exhibiting a high elevated temperature strength as well as some room temperature ductility as a new class of heat resisting structural materials. The idea behind this approach is expectations for the L21 phase to provide high elevated temperature strength, whereas the Ll2 phase provides some room temperature ductility. Compositional optimization in the room temperature ductility of the Ll2 (Co,Ni)3(Al,Ti) is first carried out and then, based on the result, several L12/L21 two phase alloys are designed. It is found that a few to several per cent room temperature bend ductility is obtained in such two-phase alloys.

scholarly journals Progress in Biodegradable Flame Retardant Nano-Biocomposites

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 741
Author(s):  
Zorana Kovačević ◽  
Sandra Flinčec Grgac ◽  
Sandra Bischof
Keyword(s):  
Mechanical Properties ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Circular Economy ◽  
Nanocomposite Materials ◽  
Thermal And Mechanical Properties ◽  
Specific Group ◽  
New Class ◽  
Research Initiatives ◽  
Positive Properties

This paper summarizes the results obtained in the course of the development of a specific group of biocomposites with high functionality of flame retardancy, which are environmentally acceptable at the same time. Conventional biocomposites have to be altered through different modifications, to be able to respond to the stringent standards and environmental requests of the circular economy. The most commonly produced types of biocomposites are those composed of a biodegradable PLA matrix and plant bast fibres. Despite of numerous positive properties of natural fibres, flammability of plant fibres is one of the most pronounced drawbacks for their wider usage in biocomposites production. Most recent novelties regarding the flame retardancy of nanocomposites are presented, with the accent on the agents of nanosize (nanofillers), which have been chosen as they have low or non-toxic environmental impact, but still offer enhanced flame retardant (FR) properties. The importance of a nanofiller’s geometry and shape (e.g., nanodispersion of nanoclay) and increase in polymer viscosity, on flame retardancy has been stressed. Although metal oxydes are considered the most commonly used nanofillers there are numerous other possibilities presented within the paper. Combinations of clay based nanofillers with other nanosized or microsized FR agents can significantly improve the thermal stability and FR properties of nanocomposite materials. Further research is still needed on optimizing the parameters of FR compounds to meet numerous requirements, from the improvement of thermal and mechanical properties to the biodegradability of the composite products. Presented research initiatives provide genuine new opportunities for manufacturers, consumers and society as a whole to create a new class of bionanocomposite materials with added benefits of environmental improvement.

Intermetallics of Aluminum

2019 ◽  
Author(s):  
Georg Frommeyer ◽  
Sven Knippscheer
Keyword(s):  
Crystal Structure ◽  
Mechanical Properties ◽  
Plastic Deformation ◽  
High Temperature ◽  
Physical Properties ◽  
Intermetallic Compounds ◽  
Oxidation Behavior ◽  
Physical And Mechanical Properties ◽  
Structural Materials

Aluminum-rich intermetallic compounds of the Al3X-type with transmission metals (X = Ti. Zr, Nb, V) of Groups IVb and Vb are of interest in the development of novel high-temperature and lightweight structural materials. This article describes the important physical and mechanical properties of trialuminides with DO22 structure and their L12 variations. Topical coverage includes: crystal structure and selected physical properties, plastic deformation, oxidation behavior, and applications.

scholarly journals Optical Properties and Mechanical Modeling of Acetylated Transparent Wood Composite Laminates

Materials ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2256
Author(s):  
Kyle E. O. Foster ◽  
Kristen M. Hess ◽  
Garret M. Miyake ◽  
Wil V. Srubar
Keyword(s):  
Mechanical Properties ◽  
Composite Laminates ◽  
Plate Theory ◽  
Tensile Modulus ◽  
Fiber Direction ◽  
New Class ◽  
Polymer Resin ◽  
Optical Responses ◽  
Optical And Mechanical Properties ◽  
Wood Template

Transparent wood composites (TWCs) are a new class of light-transmitting wood-based materials composed of a delignified wood template that is infiltrated with a refractive- index-matched polymer resin. Recent research has focused primarily on the fabrication and characterization of single-ply TWCs. However, multi-ply composite laminates are of interest due to the mechanical advantages they impart compared to the single ply. In this work, 1- and 2-ply [0°/90°] TWC laminates were fabricated using a delignified wood template (C) and an acetylated delignified wood template (AC). The optical and mechanical properties of resultant C and AC TWC laminates were determined using ultraviolet-visible spectroscopy (UV-Vis) and tensile testing (5× replicates), respectively. In addition, the ability of classical lamination plate theory and simple rule of mixtures to predict multi-ply tensile modulus and strength, respectively, from ply-level mechanical properties were investigated and are reported herein. Experimental results highlight tradeoffs that exist between the mechanical and optical responses of both unmodified and chemically modified TWCs. Template acetylation reduced the stiffness and strength in the 0° fiber direction by 2.4 GPa and 58.9 MPa, respectively, compared to the unmodified samples. At high wavelengths of light (>515 nm), AC samples exhibited higher transmittance than the C samples. Above 687 nm, the 2-ply AC sample exhibited a higher transmittance than the 1-ply C sample, indicating that thickness-dependent optical constraints can be overcome with improved interfacial interactions. Finally, both predictive models were successful in predicting the elastic modulus and tensile strength response for the 2-ply C and AC samples.

scholarly journals New Class of Crosslinker-Free Nanofiber Biomaterials from Hydra Nematocyst Proteins

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Theresa Bentele ◽  
Federico Amadei ◽  
Esther Kimmle ◽  
Mariam Veschgini ◽  
Philipp Linke ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Disulfide Bonds ◽  
Human Mesenchymal Stem Cells ◽  
Bulk Water ◽  
Volume Changes ◽  
E Coli ◽  
New Class ◽  
Polyproline Motif ◽  
Protein Components ◽  
Novel Protein

AbstractNematocysts, the stinging organelles of cnidarians, have remarkable mechanical properties. Hydra nematocyst capsules undergo volume changes of 50% during their explosive exocytosis and withstand osmotic pressures of beyond 100 bar. Recently, two novel protein components building up the nematocyst capsule wall in Hydra were identified. The cnidarian proline-rich protein 1 (CPP-1) characterized by a “rigid” polyproline motif and the elastic Cnidoin possessing a silk-like domain were shown to be part of the capsule structure via short cysteine-rich domains that spontaneously crosslink the proteins via disulfide bonds. In this study, recombinant Cnidoin and CPP-1 are expressed in E. coli and the elastic modulus of spontaneously crosslinked bulk proteins is compared with that of isolated nematocysts. For the fabrication of uniform protein nanofibers by electrospinning, the preparative conditions are systematically optimized. Both fibers remain stable even after rigorous washing and immersion into bulk water owing to the simultaneous crosslinking of cysteine-rich domains. This makes our nanofibers clearly different from other protein nanofibers that are not stable without chemical crosslinkers. Following the quantitative assessment of mechanical properties, the potential of Cnidoin and CPP-1 nanofibers is examined towards the maintenance of human mesenchymal stem cells.

Application of Microbial Polyesters-Polyhydroxyalkanoates as Tissue Engineering Materials

2005 ◽  
Vol 288-289 ◽  
pp. 437-440 ◽  
Author(s):  
Guo Qiang Chen ◽  
Qiong Wu ◽  
Ya Wu Wang ◽  
Zhong Zheng
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Surface Treatment ◽  
Surface Properties ◽  
Three Dimensional ◽  
Material Surface ◽  
New Class ◽  
Molecular Studies ◽  
Cartilage Cells ◽  
Engineering Materials

Poly(hydroxybutyrate-co-hydroxyhexanoate) (PHBHHx) has improved mechanical properties over the existing PHA and our results have shown that PHBHHx has better biocompatibility over polyhydroxybutyrate (PHB) and polylactic acid (PLA). Surface treatment with lipases dramatically changed the material surface properties and increased the biocompatibility of the PHBHHx. PHBHHx and its PHB blends had been used to make three dimensional structures and it has been found that cartilage, osteoblast, and fibroblasts all showed strong growth on the PHBHHx scaffolds. The growth was much better compared with PLA. The molecular studies also showed that mRNA encoding cartilages were strongly expressed when cartilage cells were grown on the PHBHHx. As PHBHHx has strong mechanical properties, easily processible and biodegradable, this material can be used to develop a new class of tissue engineering materials.

Sign in / Sign up

Export Citation Format

Share Document