Low Strength
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2022 ◽  
Vol 12 (2) ◽  
pp. 713
Esther Nneka Anosike-Francis ◽  
Paschal Ateb Ubi ◽  
Ifeyinwa Ijeoma Obianyo ◽  
Godwin Mong Kalu-Uka ◽  
Abdulhakeem Bello ◽  

This study investigates the feasibility of creating a clay polymer-based composite using cowpea husk (CPH) as filler for production of roof tiles. Polymeric composites were fabricated by mixing unsaturated polyester (UPT) resin with cowpea husk at different filler weights and curing. A hybrid composite was produced with the addition of 3 wt.% clay and all samples produced were subjected to flexural, hardness and dynamic mechanical analysis (DMA) tests. The effect of clay addition on the mechanical and thermo-mechanical behaviour of formulated composites was investigated. The morphological analysis of the mono and hybrid system shows a rough and coarse inhomogeneous surface with voids created due to the addition of CPH filler for the mono reinforced and clay uniformly filling the voids that were created by the CPH in the hybrid composite. It is observed that hardness, tensile modulus and flexural modulus of hybrid composites increase with an increase in the CPH contents, while the strength and flexural strength all decrease with filler content. The optimal composition was obtained using Grey relational analysis (GRA) at 18% CPH for both mono and hybrid composite. The results imply that the composite combination can be used in making rooftiles and/or also in applications where low strength is required.

Microstructure and corrosion behavior of nanocrystalline SUS304 by dry ice shot peening has been investigated in detail in term of phase transformation. SUS304 as metastable austenitic stainless has excellent corrosion resistance and induced martensite by shot peening process. However, the SUS304 has quite low strength which is difficult to wear as metallic component. The dry ice shot peening process was carried out on SUS304 surface for one and three hours. The microstructure was observed by transmission electron microscope (TEM) and scanning electron microscope (SEM) equipped with electron back-scattered diffraction (EBSD). The phase transformation was analyzed by X-ray diffraction (XRD). The corrosion testing was carried out in 3.5% NaCl solution. The result indicated that the grain size of SUS304 surface was finer by deformation due to dry ice shot peened process. The hardness was improved properly by the increasing the shot peened time, and the corrosion resistance was increased. The XRD results showed that three hours shot peening process induced martensite phase of SUS304 by 15 m thickness. It can be summarized that the dry ice shot peening can be induced phase transformation due to high deformation on the SUS304 surface

2022 ◽  
Hyun-Seok Yun ◽  
Seong-Woo Moon ◽  
Yong-Seok Seo

Abstract Determining the mechanical properties of fault-core-zone materials is challenging because of the low strength of such materials, which affects field sampling, specimen preparation, and laboratory testing. We overcame this problem by preparing and testing mechanical properties of 132 artificial fault-core-zone specimens consisting of mixtures of breccia, sand, clay, and water. The unconfined compressive strength (UCS), elastic modulus (E), and penetration resistance value (PRV) of these fault-core-zone materials were measured, and the effects of breccia content and water content on mechanical properties were assessed. Results show that UCS is inversely proportional to breccia content and water content, and that E is inversely proportional to water content. Furthermore, the inverse relationship of UCS with water content varies with breccia content. UCS is proportional to both PRV and E, and the relationship for each varies with breccia content. High coefficients of determination (R2 = 0.62–0.88) between the parameters suggest that breccia content, water content, and PRV are potentially useful parameters for estimating the mechanical properties of fault core zones.

2022 ◽  
Vol 905 ◽  
pp. 221-230
Hong Wei Pan ◽  
Chong Guang Zang ◽  
Yu Long Zhang

To solve the problems of low strength and high viscosity of room temperature vulcanized liquid silicone rubber, a series of terminated vinyl silicone oil were designed and synthesized, and low viscosity and high strength silicone rubber were prepared by the mechanical reinforcing agent. the results show that the molecular structure of the vinyl-terminated silicone oil has a significant effect on the mechanical properties and viscosity of the silicone rubber, and the best performance is found when the content of vinyl-terminated silicone oil is 0.16%. The low viscosity and high strength silicone rubber prepared from it was reinforced by vinyl MQ resin and fumed silica, which had a significant effect on improving the performance. Its tensile strength increased to 5.03 MPa, elongation at break to 338.90%, and tear strength to 7.15 kN/m compared to conventional silicone rubber, while the hardness increased to 43°. The viscosity is 34.9 Pa•s. The compression modulus is 7.48 MPa.

Sebastiaan Dalle ◽  
Jolan Dupont ◽  
Lenore Dedeyne ◽  
Sabine Verschueren ◽  
Jos Tournoy ◽  

Abstract The age-related loss of muscle strength and mass, or sarcopenia, is a growing concern in the ageing population. Yet, it is not fully understood which molecular mechanisms underlie sarcopenia. Therefore, the present study compared the protein expression profile, such as catabolic, oxidative, stress-related and myogenic pathways, between older adults with preserved (8 ♀ and 5 ♂; 71.5 ±2.6 years) and low muscle strength (6 ♀ and 5 ♂; 78.0±5.0 years). Low muscle strength was defined as chair stand test time >15 seconds and/or handgrip strength <16kg (women) or <27kg (men) according the EWGSOP2 criteria. Catabolic signaling (i.e. FOXO1/3a, MuRF1, MAFbx, LC3b, Atg5, p62) was not differentially expressed between both groups, whereas the mitochondrial marker COX-IV, but not PGC1α and citrate synthase, was lower in the low muscle strength group. Stress factors CHOP and p-ERK1/2 were higher (~1.5-fold) in older adults with low muscle strength. Surprisingly, the inflammatory marker p-p65NF-κB was ~7-fold higher in older adults with preserved muscle strength. Finally, expression of myogenic factors (i.e. Pax7, MyoD, desmin; ~2-fold) was higher in adults with low muscle strength. To conclude, whereas the increased stress factors might reflect the age-related deterioration of tissue homeostasis, e.g. due to misfolded proteins (CHOP), upregulation of myogenic markers in the low strength group might be an attempt to compensate for the gradual loss in muscle quantity and quality. These data might provide valuable insights in the processes that underlie sarcopenia.

2022 ◽  
Hazlami Fikri Basri ◽  
Aznah Nor Anuar ◽  
Mohd Hakim Abdul Halim

Abstract Aerobic granular sludge (AGS) technology is a promising biological method for modern wastewater treatment. However, granulation time have become a major issue for the application of AGS technology especially in low strength wastewater. Recent studies on granulation are focusing towards rapid start-up granulation process. Diatomite, a friable light-coloured sedimentary rock was introduces in this study to enhanced the granules formation. This study highlight the effect of diatomite towards the microbial community during the transformation of seed sludge until development of granules. DNA extraction and Metagenomic analysis was conducted with three samples (seed sludge, control AGS, AGS diatomite) to compare the microbial community. The microbial community analysis revealed the alpha diversity, phylum and class level, and the abundance of EPS producing bacteria of each bacteria samples respectively. Diatomite has a significant influence towards the microbial diversity (High Shannon index alpha diversity). Also, diatomite promotes the abundance of functional bacteria especially EPS producing bacteria, which seen as a crucial elements in granulation process.

2022 ◽  
Vol 2163 (1) ◽  
pp. 012009
N Y Perez-Rangel ◽  
E Florez-Solano ◽  
E Espinel-Blanco

Abstract At present, it is necessary to use various materials to manufacture parts used in different fields such as industry, food, automotive, aviation, etc. Depending on the purpose of the part is the manufacturing process and the materials used, the most widely used material is aluminum, for its mechanical properties and low strength/weight ratio, aluminum is one of the most demanded materials, you can find various manufacturing processes, by casting, molding, injection and machining, This last process is developed by separating materials in the form of fragments, so that the required parts can be created, the chips are completely discarded, causing environmental contamination. This research aims to recover aluminum chips produced in the metal processing workshop and machine tool laboratory of the Universidad Francisco de Paula Santander, Seccional Ocaña, Colombia, to create a metal sponge of aluminum that will also allow nano-reinforcement with carbon nanotubes under special conditions for the collection of petroleum or petroleum derivatives when environmental impacts occur on water sources, in this way, the use of aluminum chip will help protect the environment and the metal sponge will reduce the risk that oil and its derivatives will generate environmental impact reflected by the spill in water sources.

2022 ◽  
Vol 76 (1) ◽  
Diana R. Feldhacker ◽  
Whitney Lucas Molitor ◽  
Lou Jensen ◽  
Helene Lohman ◽  
Angela M. Lampe

Importance: Interventions that promote function, medication reconciliation, and skin integrity assist occupational therapy practitioners in demonstrating professional value, improving quality, and reducing health care costs. Objective: In this systematic review, we focus on three outcome areas of the Improving Medicare Post-Acute Care Transformation (IMPACT) Act of 2014: functional status, medication reconciliation, and skin integrity. Data Sources: We conducted a search of the literature published between 2009 and 2019 in CINAHL, Cochrane, MEDLINE, PsycINFO, OTseeker, and Scopus. We also hand searched the systematic reviews and meta-analyses in our search results for articles that met our inclusion criteria. Study Selection and Data Collection: This study used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Findings: We found 47 articles that address the three outcome areas. Regarding functional status, low strength of evidence is available for cognition and functional mobility interventions to support functional performance, moderate strength of evidence supports interventions for vision, and moderate evidence supports task-oriented and individualized interventions to promote activities of daily living (ADL) outcomes among people with neurological conditions. Strong strength of evidence supports individualized occupational therapy interventions focusing on medication adherence. Low strength of evidence was found for occupational therapy interventions to reduce pressure ulcers and promote skin integrity. Conclusion and Relevance: The evidence supports occupational therapy interventions to improve functional status in ADLs and medication management. Additional research is needed that examines the outcomes of occupational therapy interventions for other areas of function and skin integrity. What This Article Adds: We found evidence to support occupational therapy interventions that align with value-based measures in the three outcome areas of interest. The effectiveness of these interventions highlights the viability of occupational therapy as an essential profession and the worth of occupational therapy to the public, potential clients, and payers.

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