Nanomaterials have unique application features which can mainly be associated with their size properties. These materials have much higher surface area than the normal size interval variant of the same materials. Due to these properties nanomaterials are widely used in the industry. Food industry and the agrarian sector are using these materials to an increasing extent [1-2]. The main goal of the nano size components and additives are the improvement of some parameters of the food manufacturing process, the elongation of the best before date of the food and the improvement of the texture, stability and the consistence of the food. Probably nanomaterials will play an important role in the development of the food industry, moreover, it can be anticipated that nanotechnology will also appear there and will influence the whole food chain. It should be remarked that food industry is using several nano size materials which are not referred to as nanomaterials. Some examples are the micelles of some proteins and fatty acids. The particle size of milk protein is in the 2-200 nm interval [3]. Considering all these, the aim of our present work was a thorough review and summary of the current applications.

During their application, behavior of nanomaterials can differ from the generally known, widely applied, considering their risks, familiar, legislated materials. Since they gained importance rapidly, we did not have enough time to study the mechanism of action of these materials in details. The short- and long-term effects of these materials are only scarcely known or not known. However, since the middle of the 2000s decade, an increasing trend can be noticed regarding the scientific literature dealing with the risk assessment of nanomaterials. It is important to pay special attention to the full life-cycle of the nanomaterials and to know the short- and long-term effects of some processes like mining, production, application, deposition, neutralization on our environment and on the health and security of the directly or indirectly affected people. In our paper we examine in detail the effects which can have an effect on human health and safety during the application of nanomaterials. We summarized the collected parameters to be tested, and we cathegorized them into topic areas in order to give assistance in the preparation risk assessments associated with nanomaterials, thus even the laymen can have a good overview on the critical factors in aspects of human health.

During the evaluation of certain hydrocarbon fields, for the petroleum engineering tests, natural rock core samples are needed. If there is a shortage of such samples, preparation and development of artificially consolidated rock samples become necessary. These samples can be made of different compositions and by using different technologies. The used model materials can play a role in the exploitation of petroleum and natural gas, and they can also promote the development, selection or application of secondary or tertiary technologies in conventional and non-conventional reservoirs. The process developed and used by us makes it available to construct these rock samples from different raw materials, under different pressure and temperature conditions and by using different post-treatment methods. In this paper, the changes of petrophysical parameters (porosity, permeability) originating from a CO2-rich environment ensured by a post-treatment (cure) were analyzed. The authors proposed further investigations of additional important parameters – zeta-potential, wettability – which could alter during different preparation methods of artificially consolidated rock samples, and by this, they could also enhance the research of geological storage of CO2 and EOR technologies.

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The stability of different type nanomaterials play an important role among recent scientific and industrial challenges, including the examination of the effect of polymers, surfactants and their mixture on surface and electric surface properties and aggregation extent of dispersed particles, which are of utmost importance. Bentonite and its composite with different nanomaterials are frequently used for instance in environmental protection for wastewater treatment, since due to their great specific surface area they have excellent sorption properties. There are several publications in the literature for the application of bentonite in drilling muds. By using them the fluid loss can be decreased during the drilling process, the filtration of the fluid can be increased, it also improves the rheological properties and the formation damage can also be mitigated. During research the investigation and the analysis of the zeta-potential of nanoparticles and their composites at different pH and salt content can be an interesting topic. During our experiments the electric surface properties of nanomagnetite synthetized in laboratory (NM), cation exchanged bentonite from Mád (Be) and the composite particles of these particles were investigated. Hybrid particles of different compositions (9:1, 7:3, 1:1, 3:7, 1:9) were analyzed at different potassium chloride concentrations (0.1 – 0.0001 M). The surface adsorption on the surface, i.e. the change in the surface charge can be traced well by analyzing the obtained zeta-potential values. The behavior of such systems was observed in the full pH interval, thus, valuable data were obtained regarding the colloidal stability. As for the stability, different requirements may emerge in practice, there are application fields where the colloidally stable system is advantageous, on the other hand, in some cases, ceasing the stabile system is the goal. Our investigations are of high importance in terms of stability and its characterization [1].