there are no appreciable amounts of nickel resources in iran; therefore, secondary resources of this element are to be more considered in future. spent nickel catalysts that are used in various industrial processes are one of them. for example nickel catalyst that is used in hydrogenation of edible oil have large amounts of nickel and they are generally supported on porous materials like silica...

The thesis is focussed on low consistency (LC) refining of mechanical pulp. The research included evaluations of energy efficiency, development of pulp properties, the influence of fibre concentration on LC refining and effects of rotor position in a two-zoned LC refiner. Trials were made in mill scale in a modern TMP line equipped with an MSD Impressafiner for chip pre-treatment, double disc (...

The carcinogenicity of nickel compounds has been shown in numerous epidemiological and animal studies. Carcinogenesis is generally considered as a multistep accumulation of genetic alterations. Nickel, however, being highly carcinogenic is only a weak mutagen. We hypothesize that nickel may act by modulating signaling pathways, and subsequently by reprogramming transcription factors. Insoluble ...

The in vivo binding of nickel to chromatin, nucleic acids, and nuclear proteins from rat kidney and liver was investigated. Evidence is presented for the direct interaction of nickel with chromatin from rat tissues following i.p. injection of nickel carbonate. A gentle DNA isolation procedure was developed and used to isolate nickel-bound whole chromatin, DNA + histone octamer complex (polynucl...

BACKGROUND The former 'EU Nickel Directive' and, since 2009, the REACH Regulation (item 27 of Annex XVII) do not include all metallic objects. The nickel content of tools is not regulated by the REACH Regulation, even if they may come into in prolonged contact with the skin. Tools might be possible sources of nickel and cobalt sensitization, and may contribute to elicitation and maintenance of ...

The facultative anaerobic enterobacterium Escherichia coli requires the activity of nickel-containing hydrogenase for its anaerobic growth. Deficiency of the specific nickel transport system led to a hydrogenase-minus phenotype and slowed down the fermentative growth in the nik mutant. Addition of 300 microM nickel to the growth medium could restore the hydrogenase activity. This restoration re...

The many chemical forms of nickel differ in physicochemical properties and biological effects. Health assessments for each main category of nickel species are needed. The carcinogenicity assessment of water-soluble nickel compounds has proven particularly difficult. Epidemiologic evidence indicates an association between inhalation exposures to nickel refinery dust containing soluble nickel com...

Nickel serves as a cofactor for various microbial enzymes including superoxide dismutase (SOD) found in Streptomyces spp. In Streptomyces coelicolor, nickel represses and induces production of Fe-containing and Ni-containing SODs, respectively, primarily at the transcriptional level. We identified the nickel-responsive regulator (Nur), a Fur (ferric-uptake regulator) homologue, which binds to t...

possibility of replacing whole soy flour for chocolate fat in chocolate production and its impact on textural, rheological and sensory properties of low fat chocolate was explored. for doing this, whole soy flour in 5 levels (0, 2,4,6,8 percent) and two refining times (105 and 135 minutes) was employed. results indicated that longer refining time gave rise to reduction in particles size and inc...