A LISA Model of the Nonlinear and Hysteretic Response of Interstitial Regions to Applied Stresses

1986 ◽

Vol 44 ◽

pp. 500-501

Author(s):

R-R. Lee

Keyword(s):

Martensitic Transformation ◽

High Strength ◽

Nucleation And Growth ◽

In Situ Observation ◽

Considerable Potential ◽

Transmission Electron ◽

Structural Applications ◽

Applied Stresses ◽

Kinetics Of

Partially-stabilized ZrO2 (PSZ) ceramics have considerable potential for advanced structural applications because of their high strength and toughness. These properties derive from small tetragonal ZrO2 (t-ZrO2) precipitates in a cubic (c) ZrO2 matrix, which transform martensitically to monoclinic (m) symmetry under applied stresses. The kinetics of the martensitic transformation is believed to be nucleation controlled and the nucleation is always stress induced. In situ observation of the martensitic transformation using transmission electron microscopy provides considerable information about the nucleation and growth aspects of the transformation.

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Effects of Loading Rates on the Hysteretic Response of Resilient Variable Friction Dampers

International Journal of Steel Structures ◽

10.1007/s13296-021-00519-5 ◽

2021 ◽

Author(s):

Yongwei Wang ◽

Zhen Zhou ◽

Linjie Huang

Keyword(s):

Friction Dampers ◽

Loading Rates ◽

Variable Friction ◽

Hysteretic Response

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Mechanical Properties and Corrosion Resistance of TiAl6V4 Alloy Produced with SLM Technique and Used for Customized Mesh in Bone Augmentations

Applied Sciences ◽

10.3390/app11125622 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5622

Author(s):

Nicola De Angelis ◽

Luca Solimei ◽

Claudio Pasquale ◽

Lorenzo Alvito ◽

Alberto Lagazzo ◽

...

Keyword(s):

Sem Analysis ◽

Bone Augmentation ◽

Specific Test ◽

Chemical Action ◽

Three Point Bending ◽

Custom Made ◽

Manufacturing Techniques ◽

Mechanical Properties And Corrosion ◽

Flexural Tests ◽

Applied Stresses

Bone augmentation procedures represent a real clinical challenge. One option is the use of titanium meshes. Additive manufacturing techniques can provide custom-made devices in titanium alloy. The purpose of this study was to investigate the material used, which can influence the outcomes of the bone augmentation procedure. Specific test samples were obtained from two different manufacturers with two different shapes: surfaces without perforations and with calibrated perforations. Three-point bending tests were run as well as internal friction tests to verify the Young’s modulus. Test samples were placed in two different buffered solutions and analyzed with optical microscopy. A further SEM analysis was done to observe any microstructural modification. Three-point flexural tests were conducted on 12 specimens. Initial bending was observed at lower applied stresses for the perforated samples (503 MPa) compared to non-perforated ones (900 MPa); the ultimate flexural strength was registered at 513 MPa and 1145 MPa for perforated and non-perforated samples, respectively. Both microscopic analyses (optical and SEM) showed no significant alterations. Conclusions: A normal masticatory load cannot modify the device. Chemical action in the case of exposure does not create macroscopic and microscopic alterations of the surface.

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Stochastic Fracture Analysis of the Laminated Composite Plates Subjected to Different Types of Biaxially Applied Stresses by Implementing SXFEM

Iranian Journal of Science and Technology Transactions of Mechanical Engineering ◽

10.1007/s40997-021-00434-4 ◽

2021 ◽

Author(s):

Shailesh P. Palekar ◽

Achchhe Lal

Keyword(s):

Laminated Composite ◽

Composite Plates ◽

Fracture Analysis ◽

Laminated Composite Plates ◽

Different Types ◽

Applied Stresses

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Investigation of Hydrothermally Stressed Silicone Rubber/Silica Micro and Nanocomposite for the Coating High Voltage Insulation Applications

Materials ◽

10.3390/ma14133567 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3567

Author(s):

Faiza Faiza ◽

Abraiz Khattak ◽

Safi Ullah Butt ◽

Kashif Imran ◽

Abasin Ulasyar ◽

...

Keyword(s):

Silicone Rubber ◽

Structural Changes ◽

Polymer Chains ◽

Hydrothermal Conditions ◽

Silica Filler ◽

Before And After ◽

Aging Conditions ◽

The Stability ◽

Micro Silica ◽

Applied Stresses

Silicone rubber is a promising insulating material that has been performing well for different insulating and dielectric applications. However, in outdoor applications, environmental stresses cause structural and surface degradations that diminish its insulating properties. This effect of degradation can be reduced with the addition of a suitable filler to the polymer chains. For the investigation of structural changes and hydrophobicity four different systems were fabricated, including neat silicone rubber, a micro composite (with 15% micro-silica filler), and nanocomposites (with 2.5% and 5% nanosilica filler) by subjecting them to various hydrothermal conditions. In general, remarkable results were obtained by the addition of fillers. However, nanocomposites showed the best resistance against the applied stresses. In comparison to neat silicone rubber, the stability of the structure and hydrophobic behavior was better for micro-silica, which was further enhanced in the case of nanocomposites. The inclusion of 5% nanosilica showed the best results before and after applying aging conditions.

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Multicellular and unicellular responses of microbial biofilms to stress

Biological Chemistry ◽

10.1515/hsz-2020-0213 ◽

2020 ◽

Vol 401 (12) ◽

pp. 1365-1374

Author(s):

Daniel K.H. Rode ◽

Praveen K. Singh ◽

Knut Drescher

Keyword(s):

Microbial Communities ◽

Stress Responses ◽

Spatial Scales ◽

Organizational Level ◽

Internal Stresses ◽

Microbial Life ◽

Microbial Biofilms ◽

Applied Stresses

AbstractBiofilms are a ubiquitous mode of microbial life and display an increased tolerance to different stresses. Inside biofilms, cells may experience both externally applied stresses and internal stresses that emerge as a result of growth in spatially structured communities. In this review, we discuss the spatial scales of different stresses in the context of biofilms, and if cells in biofilms respond to these stresses as a collection of individual cells, or if there are multicellular properties associated with the response. Understanding the organizational level of stress responses in microbial communities can help to clarify multicellular functions of biofilms.

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Kaolin based protective barrier in municipal landfills against adverse chemo-mechanical loadings

Scientific Reports ◽

10.1038/s41598-021-89787-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Partha Das ◽

Tadikonda Venkata Bharat

Keyword(s):

Ionic Strength ◽

High Ionic Strength ◽

The Self ◽

Design Parameters ◽

Layered System ◽

Geosynthetic Clay Liners ◽

Clay Liners ◽

Landfill Liner ◽

First Time ◽

Applied Stresses

AbstractIn this work, we assess the self-sealing and swelling ability of the compacted granular bentonite (GB) under an inorganic salt environment and induced overburden stresses from the landfill waste. The laboratory permeation tests with high ionic strength salt solutions reveal that the GB fails to seal and exhibits a significant mechanical collapse under different applied stresses. The applicability of GB in the form of geosynthetic clay liners as the bottom liner facilities in landfills that produce high ionic strength salt leachates, therefore, remains a serious concern. We propose an additional barrier system based on kaolin, for the first time, to address this problem. The proposed kaolin-GB layered system performs satisfactorily in terms of its sealing and swelling ability even in adverse saline conditions and low overburden stresses. The kaolin improves the osmotic efficiency of the self and also helps the underlying GB layer to seal the inter-granular voids. The estimated design parameters by through-diffusion test suggest that the kaolin-GB layered system effectively attenuates the permeant flux and suitable as a landfill liner.

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