Graphene materials containing different functional groups were prepared from a natural graphite, by means of two different oxidation methods (Hummers and Brodie). It was observed that the differences in the structure of the resultant graphite oxides (GOs) greatly affect the structure of the graphenes resulting from their thermal exfoliation/reduction. Although the oxidation of the graphite was ...

Introduction The reaction of O2 with carbonaceous surfaces has been widely studied due to its important application in industry. In general, O2 is first chemisorbed on an electron-rich site of the carbon basal plane of graphite and then, it dissociates into oxygen atoms. Oxygen will diffuse on the surface until finds a structural defect to form covalent bonds. If temperature is appropriated, CO...

We report graphitic carbon growth on crystalline and amorphous oxide substrates by using carbon molecular beam epitaxy. The films are characterized by Raman spectroscopy and X-ray photoelectron spectroscopy. The formations of nanocrystalline graphite are observed on silicon dioxide and glass, while mainly sp2 amorphous carbons are formed on strontium titanate and yttria-stabilized zirconia. Int...

Polyurethanes are widely used in car paint formulations. During thermal degradation, such polymeric systems can generate powerful asthmatic sensitizing agents named isocyanates. In body repair shops, the thermal degradation of car paint can occur during abrasive processes that generate enough heat to involve release of isocyanates in air. An environmental monitoring study was performed in two b...

partners and the CEOS space agencies. Through CEOP, CEOS will be able to contribute greatly to the understanding and prediction of the water cycle through the integrated use of satellites of CEOS members in cooperation with the IGOS partnership. CEOP represents a unique opportunity to improve the scientific basis needed to achieve overall water cycle documentation and prediction goals. Continue...

Graphite oxide constitutes carbon network with oxygen atoms both on hexagonal arrangement and the edge sites. Structural and electronic properties for graphite-oxygen complexes have been explored using first-principles total-energy calculations within the local density approximation (LDA). Band structures and density of states for the propose carbon 3D models are reported. A finite energy gap and...

Climate change adaptation is increasingly being mainstreamed into all types of organizations across the world. A large number intergovernmental (IGOs), such as European Union, World Bank, or Food and Agriculture Organization, have already started to mainstream adaptation. Yet, despite a surge in scholarly interest climate policy integration over past decade, still predominantly studied local is...

Review Isocyanates, a group of reactive chemicals [with the functional group N = C = O (NCO)] used extensively in the production of numerous polyurethane foams, coatings, and a wide array of consumer products, are a major cause of occupational asthma worldwide. The polyurethane industry has expanded dramatically , along with the number of workers and consumers at risk for exposure. Inhalation h...

In this work, the reduced graphene nanosheets were synthesized from pre-exfoliated graphite flakes. The pristine graphite flakes were firstly pre-exfoliated to graphite nanoplatelets in the presence of acetic acid. The obtained graphite nanoplatelets were treated by Hummer’s method to produce graphite oxide sheets and were finally exfoliated to graphene nanosheets by ultrasonication and reducti...

Lungs comprise the primary organ exposed to environmental toxic chemicals, resulting in diverse respiratory ailments and other disorders, including carcinogenesis. Carcinogenesis is a multi-stage phenomenon, which involves a series of genetic alterations that begin with genomic instability provoked by certain factors such as inflammation and DNA damage and end with the development of cancer. Is...