The New Rehabilitation

Sustainable Civil Infrastructures, 2018

Bituminous concrete is a premix widely used in road construction as a surface course. A high amount of expenditure is required for the construction of pavement structure. Due to increase in the magnitude of commercial vehicles, bituminous mixes are now exposed to greater stresses, and hence the performance of bituminous mixes is not good enough for paving applications. The present investigation, primly emphasizes to study the effect of filler materials and stress levels based on tensile strength on the number of load repetition sustained against the initiation of the first crack of a bituminous concrete mix. At controlled test temperature 25°C, Indirect tensile fatigue test is conducted on bituminous concrete mix prepared using Stone dust and Cement as filler materials at 10%, 20%, and 30% stress level. Further regression analysis Based on the data obtained from Indirect Tensile Fatigue test and cost estimation per km for the construction of one kilometer of bituminous concrete mix prepared using both types of filler materials is carried out. As per the limited laboratory studies carried out, It can be concluded that no of load repetition varies with the addition of filler content and filler type. Fatigue life against the cracks decreases with an increase in stress level irrespective of filler materials. In the mathematical model Stress level and tensile stress are statistically significant with fatigue life, i.e., no of load repetition of a bituminous concrete mix.

Journal of Engineering and Technological Sciences, 2018

This paper discusses the effect of nanocrystalline cellulose (NCC) when used as filler on polylactic acid (PLA)-based nanocomposites and on its mechanical properties and permeability. NCC was produced from commercial cellulose and another cellulose source, i.e. oil palm empty fruit bunch, by hydrolysis of microcrystalline cellulose with sulphuric acid and by oxidation with ammonium persulfate. The nanocomposites were made by adding nanocrystalline cellulose with varying compositions into PLA. A solvent casting method was used to produce a nanocomposite film with 5% v/v triacetin as a coupling agent. Both methods produced crystalline celluloses within the micro and nano range with mean particle size at 99.5 nm and 157.9 nm for the sulphuric acid hydrolysis and the ammonium persulfate oxidation method, respectively. The utilization of NCC as PLA composite filler increased the percentage of elongation at break with a highest percentage 19.02% for addition of 1% NCC filler. However, hig...

2012

The mechanical properties of wood polymer composites (WPC) consisting of polypropylene (PP) and mixed sawdust (SD) of meranti shorea spp. dominant and rice husk (RH) filler have been studied. Three different fillers loading of 50 wt. %, 60 wt. % and 70 wt. % were used and the process of compounding and extrusion was carried out using a twin screw extruder. Increase in flexural modulus and tensile modulus are observed while tensile strength, elongation at break, flexural strength and Izod impact strength decrease with increasing filler loading. Water absorption capability increased significantly with the increased of filler loading especially composite with 70 wt. % filler loading. Composites with 50 wt. % of filler found to have an optimum mechanical and physical property, thus being used for further study on the effect of coupling agent. The interfacial bonding between wood filler and PP matrix were studied using maleic anhydride grafted polypropylene (MAPP). Three different loadin...

Dermatologic Surgery, 2008

BACKGROUND The rapid market expansion of filler treatment options requires physicians and health care providers to fully understand differences among comparable products. OBJECTIVE The objective was to compare commercially available polymethylmethacrylate (PMMA)based soft tissue fillers to determine if there are meaningful variations in these products that could result in significantly different therapeutic profiles, especially with respect to safety. METHODS AND MATERIALS PMMA particles were evaluated for size and morphology using scanning electron microscopy (SEM) techniques. PMMA microsphere soft tissue filler products from the United States, Europe, Brazil, and Canada were compared with respect to size, homogeneity/irregularity, surface smoothness/roughness, and the presence or absence of sediment and particulate debris. RESULTS Marked differences with respect to PMMA particle morphology and related particle characteristics from a variety of products were found. Of note, some products demonstrated potentially concerning significant variability in particle size and irregular morphology. CONCLUSION It is anticipated that the variability detected in these products, based on the literature, could result in different therapeutic profiles, especially with respect to safety. Physicians and health care providers should be aware that ''comparable'' products that at a glance appear similar may not be equal.

Intervention in School and Clinic, 2014

Two diametrically opposed beliefs are held concerning the meaning of the least restrictive environment (LRE) when determining the class placements of students with disabilities. One group adheres to the placement philosophy that the LRE is always the general education setting. The other group believes that the LRE is where the students’ needs may best be met. The controversy concerning placement has resulted in a number of court cases that can provide guidance to individualized education program (IEP) teams when discussion of the LRE occurs. A checklist for use in IEP meetings is offered.

e-Polymers, 2008

The potential of exfoliated graphite nano platelets (xGnP™) as reinforcing fillers in flouroelastomer has been investigated. The dispersion of the nano graphite platelets in the polymer matrix has been investigated by WAXD, SEM, TEM, EPMA and AFM. WAXD studies indicated that the processing of composites did not change the inter-gallery distance (d-spacing) of the graphite platelets. The effect of increasing nano graphite loadings on mechanical properties like tensile strength, modulus and tear resistance has been studied. Formation of weld lines on the fracture surface of the composite has been observed by SEM. The thermal stability was determined using thermogravimetric analysis. The composites showed higher thermal stability in comparison with nonreinforced polymer.

Acta Mechanica et Automatica, 2016

The aim of the study was to compare microhardness and wear resistance of ceramic-polymer composites with micro and nano-hybrid structure. For the studies commercial composites were used, containing filler particles of the same type but different sizes, nano-sized (Filtek Ultimate) and micro-sized (Filtek Z250) composites. Tribological testing was conducted using ball-on-disc micro-tribometer. Vickers testing method was applied for microhardness studies with the use of Futertech FM 700 device. It has been demonstrated that the wear of Filtek Ultimate is almost twice lower in comparison to wear of Filtek Z250 composite. It has been concluded that the use of filler nanoparticles significantly increased wear resistance of the material. Additionally, lack of correlation between material microhardness and wear resistance has been demonstrated.

Polymer Engineering & Science, 2013

The improvement of physical and mechanical properties of nanofilled matrices significantly depends on the average size of dispersed fillers. In particular, the aspect ratio of lamellar nanofillers, such as graphene stacks, results from a combination of both filler morphology and processing techniques. In this study, nanocomposites were obtained dispersing three different graphene precursors in an epoxy resin: expanded graphite, commercial graphene nanoplatelets, and natural graphite. Epoxy matrix nanocomposites reinforced with graphene stacks, ranging from 1 wt% to 3 wt% were prepared and characterized. The structural, mechanical, and thermal properties of expanded graphitebased nanocomposites, as well as the rheological properties of liquid resin/filler suspensions, were studied and compared with those of the unfilled epoxy matrix and of the matrix filled with natural graphite and commercial nanoplatelets. The comparison of mechanical and rheological properties with simple mathematical models indicated that the aspect ratio of expanded graphite is in the order of 1000, i.e., a dispersion of nanoscale graphene stacks was obtained. This result suggests that the measurement of engineering properties of nanocomposites not only represents an objective but can also provide information about the average degree of dispersion.

2012