Background: There are a limited number of studies about the effects microbial aging on mechanical properties restorative materials. Therefore, this study aimed to evaluate effect simulated with Streptococcus mutans flexural strength different resin-based Materials and Methods: This experimental was performed blocks types materials including composite resin, giomer, resin-modified glass ionomer ...

Electro-mechanical impedance (EMI) sensing technique based on smart piezoelectric materials has emerged as a potential tool for the implementation of an online monitoring system for structural health monitoring. Many nondestructive methods have limited capabilities in monitoring of the rubber aging in a continuous manner. In this study, the feasibility of the EMI sensing technique for the onlin...

statement of problem: esthetic materials undergo some physical and mechanical changes, during their service in oral cavity. purpose: the aim of this study was the evaluation of the color and opacity stability of ideal makoo (idm) composites and compare it with tetric ceram. material and methods: fifteen disk shaped samples of each material was divided into three groups of five. different aging ...

When processing polymers in laser sintering, material aging occurs. The consequences of these aging effects are changes of material and part properties. A reduction of surface quality and the occurrence of orange peel are often found when using a material of too high viscosity. These effects are well known when processing polyamide 12. For alternative materials there is only little knowledge on...

In this paper, accelerated multi-factor aging tests in laboratory have been conducted on the stator ham of a large generator. During the period of aging, the temperature spectra of dielectric dissipation factor tan 6 of stator insulation were employed to investigate aging characteristics of insulation materials. Test results showed that the peak temperature T,,, of the tan 6 -T curve under 0.2U...

The color stability of seven commercial composite restorative materials under conditions of accelerated aging was evaluated by reflection spectrophotometry at baseline and 300, 600, and 900 h. During early aging the composites generally became darker, more chromatic, and more opaque. Changes in color of the conventional composites during aging were influenced by erosion of the resin matrices an...

AIMS/INTRODUCTION Impaired growth and premature death of β-cells are implicated in the progression of islet pathology in type 2 diabetes. It remains unclear, however, how aging affects islet cells, or whether the islet change in diabetes is an augmented process of aging. We studied age-related changes of the islet structure in Japanese non-diabetic subjects and explored the underlying mechanism...

In the advanced research fields of solar cell and energy storing materials, graphene and graphene oxide (GO) are two of the most promising materials due to their high specific surface area, and excellent electrical and physical properties. However, they was seldom studied in the traditional materials because of their high cost. Nowadays, graphene and GO are much cheaper than before with the dev...

modified bituminous materials can bring real benefits to highway maintenance/construction, in terms of better and longer lasting roads, and savings in total road life castings. this paper present the effect of there novel modifier as precipitated calcium carbonate (pcc) and two type of nanoclay on rheological properties of bitumen binder. various blends of modifier and bitumen were selected and...