Helically Perforated Thin Films -- Dependence of Mechanical Properties on Microstructure

2006 ◽  
Vol 977 ◽  
Author(s):  
Sumudu P. Fernando ◽  
Anastasia L. Elias ◽  
Michael J. Brett
Keyword(s):  
Thin Film ◽  
Pitch Angle ◽  
Finite Size ◽  
Element Model ◽  
Film Structure ◽  
Minor Effect ◽  
Helical Pitch ◽  
Microstructural Parameters ◽  
A Minor ◽  
Infinite Model

AbstractThe effects of several microstructural parameters on the mechanical behaviour of a helically perforated thin film structure, or inverse microspring, were investigated using a finite element model[1]. The parameters investigated were the helical pitch angle, the cross-section radius, and the coil spacing. The elastic modulus was found to depend most strongly on the helical pitch angle (changing by a factor of 1.3 as the pitch angle went from 35° to 70°). Variations in the coil radius and the film thickness had a minor effect on the modulus. It was also found that using a finite size model (as opposed to an infinite model using periodic boundary conditions) produced better conditioned results. A preliminary confirmation of the model's validity was performed by comparison to nanoindentation results of a nickel helically perforated thin film.

Updating the Damping Matrix Using Frequency Response Data

1995 ◽  
Author(s):  
Cécile Reix ◽  
Alain Gerard ◽  
Christian Tombini
Keyword(s):  
Frequency Response ◽  
Weighted Least Squares ◽  
Element Model ◽  
Mode Shapes ◽  
Minor Effect ◽  
Sensitivity Matrix ◽  
Damping Matrix ◽  
Stiffness Matrices ◽  
Weighted Least Squares Estimation ◽  
A Minor

Abstract This paper presents a method for the updating of the damping matrix of a linear dynamic system. For this dynamic study, it is presumed that the characteristic mass and stiffness matrices are perfectly known thanks to the updating of the experimental and calculed frequencies and mode shapes as from a finit element model. Furthermore, it is accepted that damping has only a minor effect on the frequencies and mode shapes of a structure (a hypothesis that has been verified for structures with low damping). It is proposed to adjuste the coefficients of the [D] hysteretic damping matrix as from the superposition of the experimental and analytical Frequency Response Functions (FRF). The frequencies and mode shapes are extracted from the solutions of the caracteristic equation (3) resulting from the classic dynamic equation. An analytical FRF is calculed and then used to establish the sensitivity matrix, translating the influence of the updating parameters on the FRF. To update the [D] matrix, we use a non-linear weighted least squares estimation.

Mechanical properties of helically perforated thin films

2006 ◽  
Vol 21 (5) ◽  
pp. 1101-1105 ◽  
Author(s):  
S.P. Fernando ◽  
A.L. Elias ◽  
M.J. Brett
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Pitch Angle ◽  
Film Structure ◽  
Thin Film Sample ◽  
Film Sample ◽  
Element Analysis ◽  
Nanoindentation Measurement

The mechanical behavior of a helically perforated thin film structure was simulated by finite element analysis. The validity of the results was confirmed by comparison to a nanoindentation measurement performed on a nickel helically perforated thin film sample. It was found that variation of the helical pitch angle from 35° to 70° resulted in a change of 1.5 times in the elastic modulus. Since the fabrication process used to create the actual samples allows for variation of the pitch angle, this result may enable the tailoring of materials for use in micro- and nanoscale devices.

The effect of an aluminum heat-sink layer on the laser-induced amorphization of SiOx/TeGeSn/SiOx phase-change recording films

1989 ◽  
Vol 47 ◽  
pp. 574-575
Author(s):  
Matthew R. Libera ◽  
Martin Chen
Keyword(s):  
Thin Film ◽  
Phase Change ◽  
Heat Sink ◽  
Multilayer Film ◽  
Glassy Phase ◽  
Film Structure ◽  
Glass Forming ◽  
Active Storage ◽  
Dielectric Layers ◽  
Amorphous States

Phase-change erasable optical storage is based on the ability to switch a micron-sized region of a thin film between the crystalline and amorphous states using a diffraction-limited laser as a heat source. A bit of information can be represented as an amorphous spot on a crystalline background, and the two states can be optically identified by their different reflectivities. In a typical multilayer thin-film structure the active (storage) layer is sandwiched between one or more dielectric layers. The dielectric layers provide physical containment and act as a heat sink. A viable phase-change medium must be able to quench to the glassy phase after melting, and this requires proper tailoring of the thermal properties of the multilayer film. The present research studies one particular multilayer structure and shows the effect of an additional aluminum layer on the glass-forming ability.

Improvement of monitoring of tertiary filtration with particle counting

2006 ◽  
Vol 6 (1) ◽  
pp. 1-9
Author(s):  
V. Miska ◽  
J.H.J.M. van der Graaf ◽  
J. de Koning
Keyword(s):  
Particle Surface ◽  
Minor Effect ◽  
Particle Size Distributions ◽  
Particle Volume ◽  
Mass Distributions ◽  
Particle Counting ◽  
Total Particle ◽  
Particle Counts ◽  
A Minor ◽  
Sample Dilution

Nowadays filtration processes are still monitored with conventional analyses like turbidity measurements and, in case of flocculation–filtration, with phosphorus analyses. Turbidity measurements have the disadvantage that breakthrough of small flocs cannot be displayed, because of the blindness regarding changes in the mass distributions. Additional particle volume distributions calculated from particle size distributions (PSDs) would provide a better assessment of filtration performance. Lab-scale experiments have been executed on a flocculation–filtration column fed with effluent from WWTP Beverwijk in The Netherlands. Besides particle counting at various sampling points, the effect of sample dilution on the accuracy of PSD measurements has been reflected. It was found that the dilution has a minor effect on PSD of low turbidity samples such as process filtrate. The correlation between total particle counts, total particle volume (TPV) and total particle surface is not high but is at least better for diluted measurements of particles in the range 2–10 μm. Furthermore, possible relations between floc-bound phosphorus and TPV removal had been investigated. A good correlation coefficient is found for TPV removal versus floc-bound phosphorus removal for the experiments with polyaluminiumchloride and the experiments with single denitrifying and blank filtration.

OPTIMIZATION OF THIN FILM STRUCTURE Ge2Sb2Te5 FOR OPTICAL SWITCHES

2018 ◽  
Vol 66-2 ◽  
pp. 2-8 ◽  
Author(s):  
N. V. Vishnyakov ◽  
◽  
N. M. Tolkach ◽  
P. S. Provotorov ◽  
◽  
...  
Keyword(s):  
Thin Film ◽  
Film Structure ◽  
Optical Switches ◽  
Thin Film Structure

scholarly journals Thin-Film Processing of Polypropylene and Polystyrene Sheets by a Continuous Wave CO2 Laser with the Cu Cooling Base

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1448
Author(s):  
Nobukazu Kameyama ◽  
Hiroki Yoshida ◽  
Hitoshi Fukagawa ◽  
Kotaro Yamada ◽  
Mitsutaka Fukuda
Keyword(s):  
Thin Film ◽  
Co2 Laser ◽  
Continuous Wave ◽  
Cw Laser ◽  
Heat Effects ◽  
Film Processing ◽  
Carbon Dioxide Co2 ◽  
A Minor ◽  
Residual Heat ◽  
Thin Film Processing

Carbon dioxide (CO2) laser is widely used in commercial and industrial fields to process various materials including polymers, most of which have high absorptivity in infrared spectrum. Thin-film processing by the continuous wave (CW) laser is difficult since polymers are deformed and damaged by the residual heat. We developed the new method to make polypropylene (PP) and polystyrene (PS) sheets thin. The sheets are pressed to a Cu base by extracting air between the sheets and the base during laser processing. It realizes to cut the sheets to around 50 µm thick with less heat effects on the backside which are inevitable for thermal processing using the CW laser. It is considered that the boundary between the sheets and the base is in thermal equilibrium and the base prevents the sheets from deforming to support the backside. The method is applicable to practical use since it does not need any complex controls and is easy to install to an existing equipment with a minor change of the stage.

scholarly journals Linkage mapping identifies a non-synonymous mutation in FLOWERING LOCUS T (FT-B1) increasing spikelet number per spike

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jonathan Brassac ◽  
Quddoos H. Muqaddasi ◽  
Jörg Plieske ◽  
Martin W. Ganal ◽  
Marion S. Röder
Keyword(s):  
Flowering Time ◽  
Aspartic Acid ◽  
Synonymous Substitution ◽  
Minor Effect ◽  
Phenotypic Variance ◽  
Spikelet Number ◽  
Wheat Varieties ◽  
Trait Locus ◽  
A Minor ◽  
Spikelet Number Per Spike

AbstractTotal spikelet number per spike (TSN) is a major component of spike architecture in wheat (Triticumaestivum L.). A major and consistent quantitative trait locus (QTL) was discovered for TSN in a doubled haploid spring wheat population grown in the field over 4 years. The QTL on chromosome 7B explained up to 20.5% of phenotypic variance. In its physical interval (7B: 6.37–21.67 Mb), the gene FLOWERINGLOCUST (FT-B1) emerged as candidate for the observed effect. In one of the parental lines, FT-B1 carried a non-synonymous substitution on position 19 of the coding sequence. This mutation modifying an aspartic acid (D) into a histidine (H) occurred in a highly conserved position. The mutation was observed with a frequency of ca. 68% in a set of 135 hexaploid wheat varieties and landraces, while it was not found in other plant species. FT-B1 only showed a minor effect on heading and flowering time (FT) which were dominated by a major QTL on chromosome 5A caused by segregation of the vernalization gene VRN-A1. Individuals carrying the FT-B1 allele with amino acid histidine had, on average, a higher number of spikelets (15.1) than individuals with the aspartic acid allele (14.3) independent of their VRN-A1 allele. We show that the effect of TSN is not mainly related to flowering time; however, the duration of pre-anthesis phases may play a major role.

scholarly journals IL-6 Is Not Absolutely Essential for the Development of a TH17 Immune Response after an Aerosol Infection with Mycobacterium tuberculosis H37rv

Cells ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 9
Author(s):  
Kristina Ritter ◽  
Jan Christian Sodenkamp ◽  
Alexandra Hölscher ◽  
Jochen Behrends ◽  
Christoph Hölscher
Keyword(s):  
Immune Response ◽  
Inflammatory Diseases ◽  
Mycobacterial Infection ◽  
Minor Effect ◽  
Mycobacterium Tuberculosis H37rv ◽  
Th 17 ◽  
Anti Inflammatory ◽  
A Minor ◽  
Aerosol Infection ◽  
Deficient Mice

Anti-inflammatory treatment of chronic inflammatory diseases often increases susceptibility to infectious diseases such as tuberculosis (TB). Since numerous chronic inflammatory and autoimmune diseases are mediated by interleukin (IL)-6-induced T helper (TH) 17 cells, a TH17-directed anti-inflammatory therapy may be preferable to an IL-12-dependent TH1 inhibition in order to avoid reactivation of latent infections. To assess, however, the risk of inhibition of IL-6-dependent TH17-mediated inflammation, we examined the TH17 immune response and the course of experimental TB in IL-6- and T-cell-specific gp130-deficient mice. Our study revealed that the absence of IL-6 or gp130 on T cells has only a minor effect on the development of antigen-specific TH1 and TH17 cells. Importantly, these gene-deficient mice were as capable as wild type mice to control mycobacterial infection. Together, in contrast to its key function for TH17 development in other inflammatory diseases, IL-6 plays an inferior role for the generation of TH17 immune responses during experimental TB.

scholarly journals Sweet taste of heavy water

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Natalie Ben Abu ◽  
Philip E. Mason ◽  
Hadar Klein ◽  
Nitzan Dubovski ◽  
Yaron Ben Shoshan-Galeczki ◽  
...  
Keyword(s):  
Heavy Water ◽  
Calcium Release ◽  
Homology Modelling ◽  
Taste Receptor ◽  
Chemical Properties ◽  
Sweet Taste ◽  
Minor Effect ◽  
Dynamics Simulations ◽  
A Minor ◽  
Physical And Chemical

AbstractHydrogen to deuterium isotopic substitution has only a minor effect on physical and chemical properties of water and, as such, is not supposed to influence its neutral taste. Here we conclusively demonstrate that humans are, nevertheless, able to distinguish D2O from H2O by taste. Indeed, highly purified heavy water has a distinctly sweeter taste than same-purity normal water and can add to perceived sweetness of sweeteners. In contrast, mice do not prefer D2O over H2O, indicating that they are not likely to perceive heavy water as sweet. HEK 293T cells transfected with the TAS1R2/TAS1R3 heterodimer and chimeric G-proteins are activated by D2O but not by H2O. Lactisole, which is a known sweetness inhibitor acting via the TAS1R3 monomer of the TAS1R2/TAS1R3, suppresses the sweetness of D2O in human sensory tests, as well as the calcium release elicited by D2O in sweet taste receptor-expressing cells. The present multifaceted experimental study, complemented by homology modelling and molecular dynamics simulations, resolves a long-standing controversy about the taste of heavy water, shows that its sweet taste is mediated by the human TAS1R2/TAS1R3 taste receptor, and opens way to future studies of the detailed mechanism of action.

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