Mechanics of quasi-1D ZnO nanostructures for energy harvesting

2013 ◽  
Vol 1556 ◽  
Author(s):  
Antonio Rinaldi ◽  
Rodolfo Araneo ◽  
Marialilia Pea ◽  
Andrea Notargiacomo
Keyword(s):  
Mechanical Properties ◽  
Energy Harvesting ◽  
Numerical Simulations ◽  
Size Effects ◽  
Zno Nanowires ◽  
The Other ◽  
Failure Strength ◽  
Zno Nanostructures ◽  
First Time

ABSTRACTThe mechanical properties of ZnO nanowires are the “enabling factor” for piezotronic nanogenerators. Examining the size effects entail the determination of both elastic (i.e. the Young’s Modulus, E) and failure strength (e.g. fracture, fatigue, buckling, etc.) properties of ZnO nanostructures for nanogenerators. An investigation directed to both types of effects is presented here for the first time. On one hand the strength size effects are pointed out and discussed in the framework of a generalized Weibull framework that is set forward for ZnO NWs. On the other hand, the implications of the size effects on elasticity properties are discussed and quantified using numerical simulations. The results demonstrate that the stiffening of smaller NWs can adversely affect the performance in a non-negligible manner, suggesting that both mechanical size-effects have to be considered for design purposes.

Mechanical Properties and Size Effects of ZnO Nanowires Studied by First-Principles Calculation

2010 ◽  
Vol 654-656 ◽  
pp. 1670-1673
Author(s):  
Zhan Jun Gao ◽  
You Song Gu ◽  
Yue Zhang
Keyword(s):  
Mechanical Properties ◽  
First Principles ◽  
Size Effects ◽  
Density Functional ◽  
Elastic Moduli ◽  
Axial Direction ◽  
Zno Nanowires ◽  
First Principles Calculation ◽  
Different Diameters ◽  
Ground State Energies

First-principles density functional calculations were performed to investigate mechanical properties of ZnO nanowires and the size effects. Structural optimizations were performed first, and a series of strains were applied to the nanowires in the axial direction. The ground state energies were calculated and the elastic moduli of ZnO nanowires were obtained from the energy versus strain curves. It is found that the elastic moduli of the ZnO nanowires with three different diameters (1.2, 1.5 and 1.8nm) are 136.3, 138.7 and 138.0 GPa, respectively, and that of bulk ZnO along [0001] direction is 140.1 GPa. The elastic modulus of ZnO nanowire is slightly lower than that of the bulk and it decreases as the diameter decreases. Comparisons to experimental results and theoretical predications are made.

FURTHER NOTES ON PSYLLIDAE TAKEN IN ALBERTA. (HOMOPTERA)

1939 ◽  
Vol 71 (10) ◽  
pp. 212-215 ◽  
Author(s):  
E. H. Strickland
Keyword(s):  
The Other ◽  
First Time

In 1938 (1) we recorded twenty-eight species of Psyllidae which had been captured in Alberta. Of these, twenty-one were taken, for the first time on record, during the summer of 1937. Although psyllids were far less numerous in 1938 than they had been in 1937, it is now possible to add eleven additional records to the list of species which occur in this province. These include three previously undescribed forms all of which are described by Caldwell in an accompanying article. We are indebted to Mr. Caldwell, also, for the determination of the other species here recorded.

Experimental Determination of Mechanical Properties for the Purposes of Numerical Simulations of Car Bumper Tests

2015 ◽  
Vol 732 ◽  
pp. 59-62
Author(s):  
Petr Horník
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Numerical Simulations ◽  
Experimental Determination ◽  
Input Data ◽  
Fe Analysis ◽  
Experimental Methodology ◽  
Material Input

Finite-element (FE) analysis is important instrument for prediction of plastic car bumper tests. Accuracy of FE analysis depends on accuracy of material input data. It has developed experimental methodology for identification of mechanical properties. The methodology leads to more accurate material input data for numerical simulations.

scholarly journals Determination of the Mechanical Properties of Hot Stamped Parts from Numerical Simulations

Procedia CIRP ◽  
2015 ◽  
Vol 33 ◽  
pp. 167-172 ◽  
Author(s):  
Hinnerk Hagenah ◽  
Marion Merklein ◽  
Michael Lechner ◽  
Adam Schaub ◽  
Stefan Lutz
Keyword(s):  
Mechanical Properties ◽  
Numerical Simulations

scholarly journals Influence of Vibrations During Crystallization on Mechanical Properties and Porosity of EN AC-AlSi17 Alloy

2013 ◽  
Vol 13 (1) ◽  
pp. 5-18 ◽  
Author(s):  
T. Ciućka
Keyword(s):  
Mechanical Properties ◽  
Adverse Effect ◽  
Tilt Angle ◽  
The Other ◽  
Strength Tests ◽  
New Ideas ◽  
Machining Operations ◽  
Technology Of Production

Abstract Today’s industry aims at such situation, where number of defective products, so called defects shall approach to zero. Therefore, one introduces a various changes in technology of production, introduces improvements which would help in accomplishment of this objective. Another important factor is introduction of different type of testing, which shall help in assessment which factor has significant effect on quantity of rejects, and which one could be neglected. Existence of casting rejects is unavoidable; therefore a new ideas, technologies and innovations are necessary in the entire widely understood foundry branch, in order to minimize such adverse effect. Performance of tests aimed at unequivocal determination of an effect of vibrations during crystallization on mechanical properties and porosity of the EN ACAlSi17 alloy was the objective of the present work. To do this, there were produced 36 castings from EN AC-AlSi17 alloy. All the castings underwent machining operations. Half of the casting was destined to strength tests, the other half served to determination of an effect of vibrations on porosity of the alloy. The specimens were divided into 12 groups, depending on amplitude of vibrations and tilt angle of metal mould during pouring operation.

Determination of the suitable shape for tensile tests parallel to the fibers in Guadua angustifolia Kunth specimens

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 3214-3223
Author(s):  
Ricardo Acosta ◽  
Jorge A. Montoya ◽  
Johannes Welling
Keyword(s):  
Mechanical Properties ◽  
Tensile Tests ◽  
Tension Test ◽  
The Other ◽  
Fiber Direction ◽  
Test Pieces ◽  
Tension Tests ◽  
Dog Bone ◽  
Different Types

The tension test parallel-to-fiber in anisotropic materials, such as bamboo, is one of the most important tests because it makes it possible to evaluate mechanical properties used in calculations for different types of stresses. For this type of test there are standards that apply to wood in general, others to bamboo, and other more specific ones that apply to bamboo Guadua angustifolia Kunth. These rules suggest the use of dog bone test specimens. When performing such tests parallel to the fiber direction, failures are observed in undesired zones. This document characterizes and analyzes the possible types of failures. It also evidences the difficulties presented and quantifies them finding that, for 59 failed test pieces, only 18.6% had failures within the desired zones, while the other 81.4% had failures within undesired zones in the tension test parallel to the fiber. Finally, it can be concluded that there are gaps in the rules that influence the variation of the results obtained by different authors. The dog bone test specimens are not recommended for tension tests parallel to the Guadua fiber. Rather, utilization of straight specimens is recommended with a calculated clamping height and the standard equation and protected clamping area.

scholarly journals Barkedji virus, a novel mosquito-borne flavivirus identified in Culex perexiguus mosquitoes, Israel, 2011

2013 ◽  
Vol 94 (11) ◽  
pp. 2449-2457 ◽  
Author(s):  
Jolanta Kolodziejek ◽  
Karin Pachler ◽  
Hanna Bin ◽  
Ella Mendelson ◽  
Lester Shulman ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Gene Sequence ◽  
The Other ◽  
Virus Species ◽  
Structural Elements ◽  
Vertebrate Hosts ◽  
Polyprotein Precursor ◽  
Relationship Of ◽  
First Time

Barkedji virus, named after the area of its first identification in Senegal, is a newly discovered flavivirus (FV), for which we propose the abbreviation BJV. In the present study, we report the first-time detection of BJV in Culex perexiguus mosquitoes in Israel in 2011 and determination of its almost complete polyprotein gene sequence. We characterized the BJV genome and defined putative mature proteins, conserved structural elements and potential enzyme motifs along the polyprotein precursor. By comparing polyproteins and individual proteins of BJV with several other FVs, a distant relationship of BJV to Nounane virus (NOUV), a recently described African FV, is demonstrated. Phylogenetic analysis of 55 selected flaviviral polyprotein gene sequences exhibits two major clusters, one made up of the classical three clades of FVs: mosquito-borne, tick-borne and those without known vectors. The other cluster exclusively contains so-called ‘insect-specific’ FVs, which do not replicate in vertebrate cells. Based on our phylogenetic analysis, BJV is related to other members of the mosquito-borne clade with yet unknown vertebrate hosts, such as NOUV, Donggang virus, Chaoyang virus and Lammi virus. However, with a maximum identity of only 54 % to NOUV, BJV represents a distinct new virus species.

scholarly journals ПОЛІМЕР-ПОЛІМЕРНИЙ КОМПОЗИТ ОТРИМАНИЙ ШЛЯХОМ ПЕРЕРОБКИ ВІДХОДІВ ПВХ ЛІНОЛЕУМУ

2018 ◽  
Vol 122 (3) ◽  
pp. 45-51
Author(s):  
І. М. Костюк ◽  
Н. В. Сова ◽  
Б. М. Савченко ◽  
Р. Ш. Іскандаров ◽  
Б. П. Савчук
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Capillary Viscometer ◽  
Pet Waste ◽  
Waste Production ◽  
Hydrostatic Weighing ◽  
Mixed Waste ◽  
First Time ◽  
Positive Effect

Development of technology for the processing of mixed waste of vinyl flooring by their joint milling and plasticization. The determination of the MFI was carried out according to ISO 1133: 1997 on a capillary viscometer with a constant pressure and temperature (190 ± 0.5) ° C and a weight of 2.16 kg. The thermostability and melting temperature were determined on the Hipro RM 200C plastograph. Mechanical properties were determined on a breaking machine according to ASTM D638. Hardness - using a Shore D durometer, hydrostatic weighing density on an analytical balance RADWAG AS-X2. Equipment for milling and plasticization of a mixture of PVC / PET waste was selected. Qualitative milling of mixed waste is achieved by using a low speed rotary knife grinder with rotor speed of 300 rpm. The properties of the reinforced PVC were obtained. The strength of this film compared with the classic recipe is lower but when by using such materials in the composition it is possible to obtain a material with high physical and mechanical properties and achieve maximum non-waste production which will also have a positive effect on the economy of the enterprise. The technology for joint processing of mixed vinyl flooring waste was developed for the first time. The features of reinforcing PVC matrix with fibers of a PET was obtained at the receipt of films from mixed vinyl flooring waste. The developed technology allows to provide non-waste production of vinyl flooring at enterprises.

scholarly journals Nanoindentation of Phase and Structural Components of Pallasite Seymchan (PMG)

2019 ◽  
Vol 1 (1) ◽  
pp. 34
Author(s):  
Evgenia Brusnitsina ◽  
Razilia Muftakhetdinova ◽  
Grigoriy Yakovlev ◽  
Victor Grokhovsky
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Structural Components ◽  
Two Phase ◽  
Slow Cooling ◽  
Nanoindentation Technique ◽  
First Time

Determination of mechanical properties in multiphase bodies of extraterrestrial originis a fundamental task. In this work the hardness and Young’s modulus in the Seymchanpallasite were determined in kamacite α-Fe (Ni, Co), taenite γ-Fe (Ni, Co), plessite (α+γ),tetrataenite FeNi using nanoindentation technique. For the first time, the hardness andmodulus of elasticity of a two-phase nanostructure of cloudy zone FeNi+α-Fe(Ni,Co),formed as a result of very slow cooling (about 1 K/Myr), was determined.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

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