61 research outputs found
Developing a green register of Eco-labeled products in Romania
No full textThe green products market is growing up fast, but there is still a strong need to provide clear and verified information about their environmental performances in order to create a real consuming preference. The main preliminary results of a market survey conducted in Romania in 2010-2013 within the LIFE+ project -Promoting green products, aimed at evaluating the availability of eco-labeled products and at promoting their use, are presented in this paper. A national Green Register of type I eco-labeled products available in eight main Romanian supermarket chains was implemented and the main technical, environmental and financial characteristics were analysed for each product and product category. While the price difference between eco and non-eco products for the non-electric and non-electrical equipment products is very limited (<1%), for the eco products entailing operational costs it is significant (>13%) and still supports the widespread opinion that green products are more expensive. Further investigation is being carried out to draw a detailed comparison on the "real" costs of green products analysing their possible competitiveness in terms of operational costs an payback periods
PRODUCTION CAPACITY OF LEACHATE FROM BIHOR LANDFILL
No full textLandfilling is one of the most important issues that can be discussed nowadays related to waste management, mainly concerning the importance of what we have to do with waste quantities and how energy can be recovered. The paper proposes a threedimensional mathematical model applied to calculate the production capacity of leachate from Bihor landfill, situated in Bihor County, Romania. The leachate production capacity is related to the total amount of waste disposed in landfill during active phase. The parameters taken into consideration in the research refer only to the municipal solid waste quantity disposed and the life of the landfill. Leachate production time was divided into two well-defined periods: active phase, in which the waste was stored in landfill and the post-closure phase - the period of time until the landfill is definitively closed (30 years). The mathematical model has been elaborated and tested using TableCurve 3D software based on data provided by SC EcoBihor SA and based on the assessment of leachate quantity that can be collected from the landfill. The mathematical model proposed offers a viable solution to determine the maximum leachate production capacity during municipal solid waste landfillin
CIRCULAR ECONOMY IN ROMANIA WITHIN EUROPEAN CONTEXT
Get PDFIn the present paper we have approached some conceptual and coordinated marks of the societal reality connected to the circular economy. Generated by „the limits of certainty” regarding the future of the world business, the operationalization of the circular economy has become a part of the EU strategies and started the various stages of implementation as an active process in all countries. We have highlighted the opportunities and the risks related to the circular economy, the European dimension and, in particular, the Romanian one of this process, the role of the triad: consumer-company-natural environment, while implementing the circular economy. Circular economy is both a new approach of the societal life, based on changing the mentalities of the individuals having the role of decision makers at the company level and public administration and the decision makers – consumers, as well as a policy meant to be made operational across all entities: governmental, entrepreneurial, individually – human
The Cracking Behavior of Two Dental Composite Materials Validated through Multifractal Analyzes
No full textThe aim of this in vitro study was to analyze, both experimentally and theoretically, the mechanical behavior of two types of composite materials used in restoring dental integrity. The samples of each composite resin, namely Filtek Supreme XT (3M ESPE, St. Paul, MN, USA) and Filtek Z250 (3M ESPE, St. Paul, MN, USA), were experimentally analyzed by determining their compressive strength and fracture behavior. The fractured fragments of the samples were subjected to surface evaluation by scanning electron microscopy. The compressive stress—compressive strain dependencies revealed stronger cracking of the Filtek Supreme XT composite than Filtek Z250 prior to fracture. Theoretically, the evaluation was made by means of holographic implementations of such types of composite materials. A Hooke-type equation in a differential form is presented, which links the proposed theoretical model with the experimentally obtained data
The Role of Hidden Symmetry in Inertial Instability Dynamics
No full textInertial instability is a key process in the dynamics of rotating and stratified fluids, which arises when the absolute vorticity of the flow becomes negative. This study explored the nonlinear behavior of inertial instability by incorporating a hidden symmetry into the equations of motion governing atmospheric dynamics. The atmosphere was modeled as a complex system composed of interacting structural elements, each capable of oscillatory motion influenced by planetary rotation and geostrophic shear. By applying a symmetry-based framework rooted in projective geometry and Riccati-type transformations, we show that synchronization and structural coherence can emerge spontaneously, independent of external forcing. This hidden symmetry leads to rich dynamical behavior, including phase coupling, quasi-periodicity, and bifurcations. Our results suggest that inertial instability, beyond its classical linear interpretation, may play a significant role in organizing large-scale atmospheric patterns through internal geometric constraints
Some practical approaches of the poultry slaughter wastewater treatment by apply physico-chemical treatment
No full textAs a result of slaughtering processes, large volumes of effluents with high concentrations of organic, inorganic and microbiological pollutants are generated. The pollutants composition must be reduced by apply simultaneous processes in order, to obtain an proper effluent before discharge. In this paper, the efficiency of the physico-chemical treatment process was determined, in which a rotary sieve and the Dissolved Air Flotation (DAF) system were used. The efficiency of the DAF process was determined by comparing the quality indicators of effluents from a poultry slaughterhouse, analyzed both before and after treatment. To carry out the analysis, the samples were taken in October and November 2023, and they were determined by using certified laboratory procedures. After setting the DAF process to an optimal operating regime and chemicals dosages, the quality indicators were significantly reduced, reaching a maximum of 99%, 98%, 93%, 92%, 85%, 84%, for TSS, PO4, NO3, TKN, BOD5 and COD
Analytical Study Regarding the Seismic Response of a Moment-Resisting (MR) Reinforced Concrete (RC) Frame System with Reduced Cross Sections of the RC Beams
No full textIn the last few decades, a series of earthquakes were recorded which pointed out several deficiencies regarding the ductile seismic response of MR RC frame structures. Thus, the research problem centres around the failure mechanisms registered by the structures, which differ from the general notions of seismic response commonly found in current design standards and norms regarding seismic actions. In these conditions, in the present paper—by using comparative methods—the analytical validation of the solution of plastic hinge concentration and seismic energy dissipation in the marginal beam areas is proposed. Therefore, the RC beam sections were reduced (weakened) in the marginal areas which exhibit a plastic deformation potential, as well as in the corner areas of concrete slabs with vertical rectangular holes. The significant outcomes of this research imply the partial “guiding” of plastic hinges in the zones adjacent to beam ends. Furthermore, a reduction of both the negative effects of horizontal rigidization of the beams and the cracking and plastic deformation effects of beam-column frame joints was observed. With these technical implications, a complex mechanism of plastic deformation of MR RC frame models is registered in which all lateral elements (including RC columns) participate in the dissipation of seismic energy, without the occurrence of the “weak storey” mechanism for any of the analytical RC frame models. Furthermore, it is possible to observe the partial formation of the global plastic mechanism “Strong Columns—Weak Beams” (SCWB) for some of the structural models. Finally, the analytically studied innovative element regarding the improvement of the seismic response of pure MR RC frame structures is successfully validated
Numerical Study Regarding the Seismic Response of a Moment-Resisting (MR) Reinforced Concrete (RC) Frame Structure with Reduced Cross-Sections of the RC Slabs
No full textIn the first part of the current study, the effectiveness of the transversal cross-section reduction method for RC beams in marginal areas (by means of mechanical drilling) was validated. The said method “encourages” the formation of plastic hinges at the beam ends and, at the same time, allows for taking into account the bending stiffness of RC slabs, which is exerted upon the RC beams. In these conditions, the second part of the current research study (i.e., the current manuscript) highlights the real mode of reducing the lateral stiffness of the slabs upon the RC beams. These elements form a common body, together with the beam–column frame node. The same method as in the first part of the study—“weakening” the plates in the corner area through vertical drilling, without affecting the integrity of the reinforcing elements—was used. The analytical MR RC frame model, studied by means of the comparative method, highlights the efficiency of the transversal cross-section reduction method for RC slabs. Basically, the directing of the plastic deformations from the weakened slab areas towards the marginal areas of the reinforced concrete beams takes place. The beams rotate as far as the weakened slab areas allow its plastic deformation, thus being possible to observe the partial conservation effect of the beam–column frame joint. Furthermore, for the analytical model with the maximum number of vertical holes in the corner areas of the concrete plate, minimal plastic deformations are recorded for the marginal areas of the concrete columns. A partial conservation of the formation mechanism of the “beam-slab-frame node” common rigid block is also noted. Consequently, the dissipation of the seismic energy is made in a partially controlled and directed manner, in the “desired” areas, according to the “Strong Columns—Weak Beams” (SCWB) ductile mechanism of the lateral behavior to seismic actions for reinforced concrete frame structures. The mechanism is specified in current design norms for RC frame systems. The effectiveness of the method for reducing the transversal section of the RC plates in the corner areas by means of transversal drilling is highlighted and validated from the perspective of the local and global ductile seismic response of reinforced concrete frame structures. A significant reduction in the bending stiffness of the slabs upon the beams and a real development of the plastic hinges in the marginal areas of the beams (together with partial implications and plastic deformations) were observed
Greywater Vertical Treatment and Possibility of Reuse in the Fields from Peri-Urban Area
No full textThis study highlighted the potential for greywater reuse in irrigation of olive trees. An experimental field was set up in a household of Soukra, located northwest of Tunis City, to test the performance of vertical greywater treatment. Treated greywater (TGW) was used for the irrigation of two olive tree varieties (Chétoui and Picholine) during five years. The results show high performance of the treatment, as reflected by the good quality of TGW. The chemical and biological parameters of this TGW are under the threshold values of the Tunisian Norms of Treated Wastewaters for agriculture use (NT106.03). The BOD5 average decreased from 160.44 mg O2/L for UGW (Untreated greywater) to 15.32 mg O2/L for TGW. The COD average recorded a high reduction from 290.15 mg O2/L for UGW to 49.58 mg O2/L for TGW. The average removal rate was 90% for BOD5 and 83% for COD, proving the high performance of the treatment. The average increases in height, diameter, and olive production are significantly high for the two varieties of olive trees irrigated with treated greywater (ITGW), compared to those not irrigated and under natural conditions. In this regard, the present study has shown promising potentials for the reuse of TGW in agriculture
Studies on the Accumulation, Translocation, and Enrichment Capacity of Soils and the Plant Species Phragmites Australis (Common Reed) with Heavy Metals
No full textIn the present study, heavy metal concentrations (Cu, Zn, Pb, As) from former industrial areas were analyzed in soil and the plant species Phragmites Australis (common reed), a plant species found in shallow river banks. The objectives of the study were to determine the accumulation, translocation, and enrichment capacity of soils and plants (root, stem, leaf, and flower) with heavy metals, and to evaluate the potential of the plant species Phragmites Australis (common reed) in the phytoremediation of heavy-metal-polluted soils. The sediments and plants investigated were particularly rich in heavy metals such as Cu, Zn, Pb, and As, and Pb and Zn concentrations were determined to be of phytotoxic level. The highest transfer coefficient of heavy metals from the soil to the root of the plant species Phragmites Australis (common reed) was for the metals Cu and Zn. The transfer of heavy metals from the root of the plant species Phragmites Australis (common reed) to the aerial part of the plant was lowest for Cu. A very low enrichment factor value was recorded for the metal As. The mobility of heavy metals was generally higher from the sediment to the plant roots, with the order of the average transfer coefficient values being Cu > Zn > Pb > As for all three areas analyzed. The translocation of heavy metals from the root to the upper aerial part of the plant was in the form of As > Pb > Zn > Cu in the plant species Phragmites australis (common reed). According to the average values obtained for the three coefficients, the accumulation, translocation, and enrichment capacity of heavy metals in soil and the plant species Phragmites Australis (common reed), it can be stated that the plant species Phragmites Australis (common reed) is very suitable for use in the process of soil remediation by phytoremediation
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