OBJECTIVE To compare the deflection load characteristics of homogeneous and heterogeneous joints made by laser welding using various types of orthodontic wires. MATERIALS AND METHODS Four kinds of straight orthodontic rectangular wires (0.017 inch × 0.025 inch) were used: stainless-steel (SS), cobalt-chromium-nickel (Co-Cr-Ni), beta-titanium alloy (β-Ti), and nickel-titanium (Ni-Ti). Homogene...

Duckweeds are of special interest, as they are naturally growing weeds that have the capacity to tolerate and remove toxic pollutants, including heavy metals from the environment. Studies have revealed that duckweed (Lemna minor) can tolerate and remove heavy metals from aqueous solutions. In the present study, the efficiency of L. minor in the removal of Ni and Cr individually from aqueous sol...

The effects of metal combinations on cytotoxicity were examined following dynamic extraction by freely gyrating two spherical metals in a glass vessel. The cell viabilities of an Au alloy, a Ag-Pd-Au alloy and Ti were little affected by combinations among three metals. Cell viability ranged between 60 and 80% when precious alloys were in combination with Co-Cr or Ni-Cr alloys. Ti showed a clear...

Laurate (LA−)-intercalated nickel–chromium-layered double hydroxides (LDHs) were synthesized using the co-precipitation method and investigated as a potential photocatalyst for methylene orange (MO) degradation. For comparison, series of LDHs with various molar ratios Ni2+(or Mg2+)/Cr3+(or Fe3+)/LA−(or CO32−) prepared. X−ray diffraction (XRD) element analysis showed that Ni/Cr(2/1)−1.0 LA LDH h...

A total of 45 children's toys and jewelry were tested for total and bioaccessible metal concentrations. Total As, Cd, Sb, Cr, Ni, and Pb concentrations were 0.22-19, 0.01-139, 0.1-189, 0.06-846, 0.14-2894 and 0.08-860,000 mg kg(-1). Metallic products had the highest concentrations, with 3-7 out of 13 samples exceeding the European Union safety limit for Cd, Pb, Cr, or Ni. However, assessment ba...

introduction the pollution of the aquatic environment with heavy metals and trace elements has become a worldwide problem during recent years, because they are indestructible and most of them have toxic effects on organisms. potentially toxic elements (ptes) added to an aquatic system by anthropogenic and natural sources are distributed during their transport between different compartments of a...

Metallic piercing which have lack of resistance to sweat corrosion might be able to release metallic ions in the local tissue producing adverse effects in the human body, including allergic contact dermatitis (ACD). The aim of this study was double: 1) the metallic characterization of piercings and 2) the release of metals (Al, Co, Cr, Cu, Fe, Ir, Mn, Ni, Pd, Pt, Rh, Ti, V and Zn) in artificial...

Reticulated nickel foams were alloyed with chromium by pack-chromizing, resulting in Ni–Cr foams with 9–32 wt.% Cr and 2.6–3.5% relative density. The oxidation resistance at 1000 ◦C of the Ni–Cr foams and the corresponding bulk Ni–Cr alloys is the same, provided the foam’s higher surface area is taken into account. The foam compressive yield stress at ambient temperature is in agreement with mo...