Grigorios Kyriakopoulos

Adsorption of Pesticides on Carbonaceous and Polymeric Materials from Aqueous Solutions: A Review

Abstract Carbonaceous and polymeric materials have been extensively used in adsorption processes for the removal of pesticides from aqueous solutions. The aim of this review is the systematic and comparative presentation of the possibilities of the above adsorbents, arising from the data reported in the literature for the period 1990–2004. A brief description of each article is given in tables. The data is divided into two groups, based on the chemical structure of adsorbent (carbonaceous or polymeric material) and is given in tables. In each table information on the type of adsorbent (powder, granular, fibers, cloths, resins, cartridges etc), pesticide structure, experimental conditions, aim and results of each work, is reported. In addition, data is included concerning single pesticides adsorption, competitive adsorption, parameters of adsorption isotherms (Langmuir, Freundlich, Dubinin–Radushkevich) and kinetic models parameters (homogeneous surface diffusion model‐HSDM, equivalent background compound‐EBC, Peel model), such as surface diffusion coefficients and mass transfer coefficients. Information on adsorption yields, effect of various factors on adsorption effectiveness, static or continuous operation, laboratory, pilot or industrial scale process and combination of adsorption with other methods, is also included.

Environmental sustainability and financial feasibility evaluation of woodfuel biomass used for a potential replacement of conventional space heating sources. Part I: a Greek case study

The issue of the introduction of new environmental friendly and economical fuels to the everyday energy-consuming human activities is controversial and imperative. The recent European legislation, relative to the introduction of biofuels at local and national levels, is conformed to the above direction. The present study is driven to the wider implementation of biofuels, by applying the high heating value Woodfuel that is prolifically cultivated in the Northern Greece context. The administrative tool of the present study is the application of the RETScreen International software developed by Natural Resources Canada. The software methodology is oriented to simulate space heating of houses and domestic water heating by providing a rough and costless initial estimation of the proposed energy projects with very promising results, relevant to its financial feasibility and environmental sustainability.

Environmental sustainability and financial feasibility evaluation of woodfuel biomass used for a potential replacement of conventional space heating sources. Part II: a combined Greek and the nearby Balkan countries case study

Nowadays, the proposal of biofuels introduction to the existing energy network of European countries is directed through the recent European Legislation. The above proposal’s implementation would be successfully materialized by exploiting the Renewable Energy Sources, which are abundant in the Greek context. At the present study, the biofuels entrance to the Greek energy network is investigated through the three woodfuel biomass sources of Common Beech, Aleppo Pine and Common Fir. The above selection of the three specific woodfuel types is further examined via the potential imports of the above biomass from the nearby Balkan countries. The above woodfuel quantities are accumulated to the existing local woodfuel production, after appropriate modification of Part I experimental parameters. Additionally, the relevant proportion among the woodfuels types is examined and an environmental, economic and socioeconomic evaluation is conducted. Finally, a critical comparison between the Part I and Part II studies outcomes revealed the significant determining parameters of the scenarios’ prosperity.

Effect of ionic strength and pH on the adsorption of selected herbicides on Amberlite

The effect of ionic strength on the adsorption of alachlor, trifluralin, and prometryn on Amberlite XAD-4 polymeric resin is studied. Static adsorption experiments are carried out at pH 3–6.5 and ionic strength 0.01–2 M at 20°C. By increasing the ionic strength, the adsorption of herbicides can be significantly increased. The electrolyte addition affects both the effectiveness and efficiency of adsorption, leading eventually to a saturation of the resin surface. An explanation of the alteration of adsorption mechanisms, caused by ionic strength, is given, based mainly on the reduction in repulsive forces at the resin–herbicide interface and between adsorbing herbicide molecules, since both resin and herbicides have a polar ring as part of their structure.

Treatment of contaminated water with pesticides via adsorption

Static adsorption experiments of pesticides (alachlor, trifluralin and prometryn) on amberlite XAD-4 were carried out at pH 5. The effect of ionic strength (0.01–2 M) on the pesticides adsorption was also investigated. This effect is more pronounced for the adsorption of more polar molecules (alachlor and prometryn) compared to trifluralin adsorption. This phenomenon can be attributed to the enhancement of the polar interactions in combination with the salting out effect. Adsorption increase reached 373% for alachlor, 295% for prometryn and 234% for trifluralin. The estimated heat of adsorption (−9.8 to −23.8 kcalmol-1) based on the experimental data indicate that chemical adsorption as well as physical adsorption may occur.

Knowledge Management for Business Processes: Employees’ Recruitment and Human Resources’ Selection: A Combined Literature Review and a Case Study

Nowadays many businesses have been focused on the recruitment and selection of the appropriate employees, in order to deploy their entrepreneurial activities. Besides, on the employees’ behalf, the increased competitiveness in a worldwide level of analysis necessitates that all employees to be facilitated with advanced capabilities throughout the organizational hierarchy. In effect, these businesses adopt and develop contemporary processes for their employees’ recruitment and selection, in order to ensure increased productivity and effectiveness in a liquefied economic environment. The development of appropriate schemes of selection and recruitment, in line to the ongoing and in-field investment of education, skills and training, are determining factors to the prosperity of manufacturing industry. The ultimate goals of knowledge management in a strategic, innovative, and operational level of decision making is the achievement of greater awareness of the interactive role of science, engineering, and technology towards businesses’ success, as well as the development of flexible organizational structures that encourage entrepreneurial creativity, structural flexibility, and managerial change. In the present study, the determining parameters of employees’ recruitment and human resources’ selection are presented in a literature overview, while the inclusion of a Case Study –being based on an innovative-oriented pharmaceutical company– reveal this company’s prominent role of indentifying new markets and opportunities that might emerge and then choosing to respond to these long-term visions by activating its competitive advantages in a Management-Technology-Strategy tripartite pattern, rather than being forced into action by competitors.