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Introduction: Glass fibers with polyester resin structural composites are highly sought after in many sectors such as transportation industries, thanks to their low density and fairly good mechanical properties. However, their end-of-life management is not yet satisfactory. Composites mostly end in energy recovery in the best-case scenario or, worse, in landfills. Transformation into shreds and powders for reuse as a new source of raw material for the construction sector (concrete) is an economically and environmentally attractive recovery solution. The present study investigates the development of a concrete filled with glass/polyester composite shreds. Methods: To this end, rheological (cone spread) and physico-mechanical (density and mechanical strength in flexion and compression) characterization tests were carried out. Several mix designs were tested in order to understand the impact of introducing composite shreds as a substitute for sand. Composite shreds were introduced in the following ratios by volume: 0, 1, 1.5, 2, 2.5, 3, and 7% with water and cement ratio equal to 0.5, 0.6, and 0.7. Results and discussion: The results obtained indicate that workability decreases with the substitution of sand by shreds. For a substitution of sand by shreds of 2%, it is relatively small, and the pouring of the mortar is still feasible. The decrease can be attributed to the water absorption of the composite shreds. Concerning mechanical results, for formulations with a substitution percentage of composite shreds lower than 3%, the mechanical strength (both compression test and flexure test) is slightly higher than that of the reference sample. The increase in compressive strength that can be observed is at its maximum, equal to 10%, compared to that of the reference sample. These results are in line with density results, which are also slightly higher than that of the reference sample. This effect can be attributed to water absorption of composite shreds and the filling effect of the powders. For a percentage of substitution equal to 7%, the mechanical strength is lower than that of the reference sample (30% decrease), with a compressive strength equal to 33 MPa (47 MPa for the reference sample). For this percentage of substitution equal to 7%, a decrease in density is also observed (6% decrease) and can be explained by the porosity created by the incorporation of the composite shreds into the mortar. [ABSTRACT FROM AUTHOR]

IntroductionGlass fibers with polyester resin structural composites are highly sought after in many sectors such as transportation industries, thanks to their low density and fairly good mechanical properties. However, their end-of-life management is not yet satisfactory. Composites mostly end in energy recovery in the best-case scenario or, worse, in landfills. Transformation into shreds and powders for reuse as a new source of raw material for the construction sector (concrete) is an economically and environmentally attractive recovery solution. The present study investigates the development of a concrete filled with glass/polyester composite shreds.MethodsTo this end, rheological (cone spread) and physico-mechanical (density and mechanical strength in flexion and compression) characterization tests were carried out. Several mix designs were tested in order to understand the impact of introducing composite shreds as a substitute for sand. Composite shreds were introduced in the following ratios by volume: 0, 1, 1.5, 2, 2.5, 3, and 7% with water and cement ratio equal to 0.5, 0.6, and 0.7.Results and discussionThe results obtained indicate that workability decreases with the substitution of sand by shreds. For a substitution of sand by shreds of 2%, it is relatively small, and the pouring of the mortar is still feasible. The decrease can be attributed to the water absorption of the composite shreds. Concerning mechanical results, for formulations with a substitution percentage of composite shreds lower than 3%, the mechanical strength (both compression test and flexure test) is slightly higher than that of the reference sample. The increase in compressive strength that can be observed is at its maximum, equal to 10%, compared to that of the reference sample. These results are in line with density results, which are also slightly higher than that of the reference sample. This effect can be attributed to water absorption of composite shreds and the filling effect of the powders. For a percentage of substitution equal to 7%, the mechanical strength is lower than that of the reference sample (30% decrease), with a compressive strength equal to 33 MPa (47 MPa for the reference sample). For this percentage of substitution equal to 7%, a decrease in density is also observed (6% decrease) and can be explained by the porosity created by the incorporation of the composite shreds into the mortar.

In this work, the performance of the TEROS 12 electromagnetic sensor, which measures volumetric soil water content (θ), bulk soil electrical conductivity (σb), and temperature, is examined for a number of different soils, different θ and different levels of the electrical conductivity of the soil solution (ECW) under laboratory conditions. For the above reason, a prototype device was developed including a low-cost microcontroller and suitable adaptation circuits for the aforementioned sensor. Six characteristic porous media were examined in a θ range from air drying to saturation, while four different solutions of increasing Electrical Conductivity (ECw) from 0.28 dS/m to approximately 10 dS/m were used in four of these porous media. It was found that TEROS 12 apparent dielectric permittivity (εa) readings were lower than that of Topp's permittivity–water content relationship, especially at higher soil water content values in the coarse porous bodies. The differences are observed in sand (S), sandy loam (SL) and loam (L), at this order. The results suggested that the relationship between experimentally measured soil water content (θm) and εa0.5 was strongly linear (0.869 < R2 < 0.989), but the linearity of the relation θm-εa0.5 decreases with the increase in bulk EC (σb) of the soil. The most accurate results were provided by the multipoint calibration method (CAL), as evaluated with the root mean square error (RMSE). Also, it was found that εa degrades substantially at values of σb less than 2.5 dS/m while εa returns to near 80 at higher values. Regarding the relation εa-σb, it seems that it is strongly linear and that its slope depends on the pore water electrical conductivity (σp) and the soil type. [ABSTRACT FROM AUTHOR]

Damage from petrochemical plastics is not only a problem for the environment, but also for human health. Damage reduction is often based on consumption avoidance by making harmful products more expensive, e.g. through emission taxes for producers. This rather regulates future damage. A consumption-independent tax for citizens, on the other hand, is rare, but could be used to remedy past environmental damage. Whether and how high such a private income tax should be and what regulatory objectives it should pursue was investigated in a quasi-experimental study of 456 German households. The majority of 73%, especially women and younger people, accepted the tax, and this was initially independent of environmental awareness and own plastic avoidance efforts. Only 20% of respondents would initially favour higher taxes to be used for oil-resource preservation, followed by 30% for damage control to humans only, and this was positively associated with environmental awareness. At 37%, most people wanted to remedy damages to human and eco-capital simultaneously, which also generated the maximum tax revenues at 13% rate. Consequently, an effective levy should increasingly consider social factors of the taxed and announce for what revenues are used. This achieves maximum acceptance for better protection of environmental and human capital. The results can guide the design of a future EU plastic tax. [ABSTRACT FROM AUTHOR]

Implementing sustainable principles when landscaping parks is vital for the development of the built environment, and should take into account environmental, social, economic, and cultural aspects, in order to eliminate conflict between developmental requirements, and the need to preserve cultural and natural resources. This paper reviews the guidelines that should be considered for current and future sustainable parks in regions with a moderate climate, in order to ensure that they incorporate ecotourism, cost effective operation and maintenance, a clean environment, the promotion of renewable energy, and resource preservation. A number of parks, located in moderate climate zones, are studied in terms of aspects such as their location, topography, operation, and landscaping characteristics, to demonstrate the prevailing normative values that can be applied to sustainable park design. Prince Meshari Park, in Al-Baha city, Saudi Arabia, is employed as a case study for applying all of the guidelines proposed in this investigation, and to highlight some of their merits and limitations in terms of the current situation of the park.

Implementing sustainable principles when landscaping parks is vital for the development of the built environment, and should take into account environmental, social, economic, and cultural aspects, in order to eliminate conflict between developmental requirements, and the need to preserve cultural and natural resources. This paper reviews the guidelines that should be considered for current and future sustainable parks in regions with a moderate climate, in order to ensure that they incorporate ecotourism, cost effective operation and maintenance, a clean environment, the promotion of renewable energy, and resource preservation. A number of parks, located in moderate climate zones, are studied in terms of aspects such as their location, topography, operation, and landscaping characteristics, to demonstrate the prevailing normative values that can be applied to sustainable park design. Prince Meshari Park, in Al-Baha city, Saudi Arabia, is employed as a case study for applying all of the guidelines proposed in this investigation, and to highlight some of their merits and limitations in terms of the current situation of the park. [ABSTRACT FROM AUTHOR]

The article represents offered for use resource-preservation conceptions of effective sound-absorbing substances and noise-reducing constructions which are based on ecologically clean («green») techniques of recycled recovery of hard polymer wastes, represented by predominantly porous fiber and foamed sound-absorbing materials. The article describes results of experimental evaluation of acoustic effectiveness (reverberation sound absorption coefficient α r and equivalent sound absorption area A eq ) of breadboard models of noise-reducing constructions, composed from different types of fragmented polymer substances of porous air-permeable and air-impermeable structure. Results obtained under the conditions of diffuse sound field with the use of small reverberation room, results obtained in experimental studies give evidence of broadband effect of silencing sound energy including current low frequency range. [ABSTRACT FROM AUTHOR]

A powerful concept to cope with resource limitations and information redundancy in wireless sensor networks is the use of collaboration groups to distill information within the network and suppress unnecessary activities. When the phenomena to be monitored have large geographical extents, it is not obvious how to define these collaboration groups. This article presents the application of geometric duality to form such groups for sensor selection and non-local phenomena tracking. Using a dual-space transformation, which maps a non-local phenomenon (e.g., the edge of a half-plane shadow) to a single point in the dual space and maps locations of distributed sensor nodes to a set of lines that partitions the dual space, one can turn off the majority of the sensors to achieve resource preservation without losing detection and tracking accuracy. Since the group so defined may consist of nodes that are far away in physical space, we propose a hierarchical architecture that uses a small number of computationally powerful nodes and a massive number of power constrained motes. By taking advantage of the continuity of physical phenomena and the duality principle, we can greatly reduce the power consumption in non-local phenomena tracking and extend the lifetime of the network. [ABSTRACT FROM PUBLISHER]

The German Waste Avoidance, Recovery and Disposal Act (KrW-/AbfG) creates the demand to select for “high quality” and “environmentally sound” waste treatment and disposal techniques. Waste disposers have to choose the most “high quality” and “environmentally sound” technique among different treatment and disposal options, and therefore must have a way to comparably evaluate the different techniques. Prognos developed an assessment method called HoVe to evaluate waste treatment and disposal facilities based on these new guidelines. It adheres to international standards of life cycle assessments (DIN/ ISO 14 040). The assessment is based on emission, material, energy and economic data which already exists, making it practical, time and cost efficient. HoVe employs three Impact Categories (IC) to evaluate the impact of waste treatment. Each IC is characterized by Impact Clusters (ICL) to which original plant data are allocated. The ICL consider the amount and quality of produced products and residues from treatment processes, as well as the issues of ecological impact and energy balance. Further they incorporate economic aspects in order to assess the economic soundness of treatment and disposal plants, a requirement of the KrW-/AbfG. A pilot assessment of treatment options for shredder residues proves the viability of the method. [ABSTRACT FROM AUTHOR]

Views on the preservation of resources versus their development for recreation are compared among participants in three types of outdoor recreation: “appreciative”; activities (cross‐country skiing, hiking, and canoeing); “consumptive”; activities (fishing and hunting); and “mechanized”; activities (motorboating, snowmo‐biling, and trail biking). The results from a 1984 questionnaire survey conducted in Edmonton and Calgary, Canada, indicate a stronger preservationist orientation among participants in appreciative activities, whereas (with the exception of hunters) participants in consumptive and mechanized activities hold stronger pro‐development views. These differences cannot be attributed to simultaneous variations in socioeco‐nomic characteristics or environmental attitudes among the recreational groups. The findings suggest that differences in outdoor recreational activity preferences represent an important source of variation in views about appropriate levels of preservation versus development of Alberta's natural and wildernesss resources. [ABSTRACT FROM PUBLISHER]