Chlorophyll is utilized as a simple, inexpensive and environment-friendly (“green”) colorimetric indicator for nitrogen dioxide (NO2) gas. A drastic color change from green to yellow was observed when chlorophyll, either dissolved in CH2Cl2 solution or absorbed into paper, was exposed to NO2 gas. Other gases such as CO2 and SO2 did not exhibit any color change with chlorophyll. Spectroscopic an...

Purpose: The purpose of the current study was to examine the effect of accelerated aging on color stability of the In-Ceram and Cergogold ceramic materials. Materials and Methods: Ceramic samples with 1.0 mm in diameter and 1.5 mm in thickness were prepared in three commonly used shades. CIE Lab readings were recorded with a spectrophotometer prior to experiments and after 100-hour accelerated ...

When a visual object is briefly flashed, it appears to lag behind another moving object (flash-lag effect; FLE). Previous studies showed that a sudden change to the moving object at the time of the flash presentation would eliminate the FLE. We examined whether the FLE would be eliminated when a sudden color change was embedded in a sequence of color alternations on a moving object. Observers v...

OBJECTIVE To examine the amount of change in color and color parameters of a composite resin (Filtek P60) polymerized by five different polymerization methods. METHODS A Teflon mold (6mm in diameter, 2mm in height) was used to prepare the composite resin discs (n=10). G1: Polymerization with inlay oven; G2: Polymerization with HQTH and autoclave; G3: Polymerization with LED and autoclave; G4:...

PURPOSE In the authors' experience, the color of silicone elastomer following polymerization in molds made of gypsum products is slightly different from the color that was matched in the presence of the patient, before the silicone is packed. It is hypothesized that the investing materials and separating media have an effect on the color during the polymerization process of the silicone. MATE...

objectives: the aim of this study was to evaluate the effect of six herbal teas on the color stability of two types of nanohybrid and one microhybrid resin composite.  materials and methods: 70 disc-shaped specimens, 210 in total (7*2mm), were fabricated from each of the following materials in metal mould : tetric n ceram, grandio, gradia direct anterior. specimens were stored in distilled wate...

BACKGROUND Because Amsorb changes color when it dries, the authors investigated whether Amsorb combined with different strong base-containing carbon dioxide absorbents signals dehydration of such absorbents. METHODS Five different carbon dioxide absorbents (1,330 g) each topped with 70 g of Amsorb were dried in an anesthesia machine (Modulus CD, Datex-Ohmeda, Madison, WI) with oxygen (Amsorb ...

AIM The purpose of this study was to evaluate the effect of different denture cleansers on the color stability, surface hardness, and roughness of different denture base resins. MATERIALS AND METHODS Three denture base resin materials (conventional heat cure resin, high impact resin, and polyamide denture base resin) were immersed for 180 days in commercially available two denture cleansers (...