The effect of prior air exposure on rupture life of superalloys is reported. Oxygen is identified as a damaging species leading to severe losses in both rupture life and ductility. Similar embrittlement is observed in pure nickel and a mechanism is proposed in terms of reduced grain boundary mobility. Two cobalt base alloys and an oxide dispersion strengthened nickel base alloy do not embrittle...

Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subseq...

Mesoporous semimetal bismuth film and magnetic metal nickel and cobalt thin films have been electrodeposited from hexagonal or lamellar structured lyotropic liquid crystalline phases with polyoxyethylene surfactant. The liquid crystalline templates are characterized by low-angle X-ray diffraction (XRD) and polarized-light optical microscopy (POM). The metal films are characterized by low-angle ...

Metallic materials are the basis of dental materials science, which is an important part of dentistry. As a result of their good mechanical properties and some biological properties, metals are widely used in oral rehabilitation of dentition and mandibular defects, orthodontic and dental implants, as well as in the equipment for dental operations. Commonly used metals include nickel chromium, c...

During the 1998-2003 period, patch testing was carried out in 65 atopic dermatitis patients, 20 (31%) male and 45 (69%) female, mean age 34.7 (range 6-77) years. Twenty-six (40%) patients, 7 (27%) male and 19 (73%) female, showed positive reaction to one or more allergens. Allergic reactions were more common in women. The most common allergens were nickel (33.3%), cobalt (11.1%), fragrance mix ...

Metal allergies can be a clinical problem, especially in atopic individuals. This study is unique and contributes with new knowledge in everyday life skin care of irritant and atopic dermatitis patients. The aim of the study was to determine the frequency of positive patch test reactions to metal contact allergens (potassium dichromate, cobalt chloride, nickel sulfate, white mercury precipitate...

Mechanical properties of nickel-cobalt alloys (0-10% Co) electroformed with low internal stress in sulfamate-based solutions were investigated in as deposited and heat treated conditions. It was demonstrated that alloy properties can be modified by selecting deposition conditions and alloy composition. Recommendations on alloy selection are made based on application requirements. The higher str...

Slow strain rate tests were performed on quenched and tempered AISI 4340 steel to measure the extent of hydrogen embrittlement caused by electroplating with zinc-cobalt alloys. The effects of bath composition and pH were studied and compared with results for electrodeposited cadmium and zinc-10%nickel. It was found that Zinc-1%cobalt alloy coatings caused serious hydrogen embrittlement (EI 0.63...

The aim of the study was to determine the frequency of positive patch test reaction to different contact allergens according to patients age, sex, occupation and clinical features. Between 1999 and 2003, patch testing was performed in 3,293 patients with respective clinical diagnoses. Patch testing was done by the standard technique proposed by the International Contact Dermatitis Research Grou...

Aim: The aim of the study was to analyse the trends of allergy to the 10 most frequent contact allergens and to assess ageand sex-dependent changes of the trends in patients examined in 1996-2009. Material and methods: 4433 patients underwent patch tests with a set of allergens containing: potassium dichromate, nickel sulfate, cobalt chloride, 4-phenylenediamine, formaldehyde, thiuram mix, merc...