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The increasing scarcity of virgin natural resources and the need for sustainable waste management in densely populated urban areas have heightened the importance of developing new recycling technologies. One promising approach involves recycling agricultural waste in construction applications and transforming it into secondary products. This is anticipated to reduce the demand for new resources and lower the environmental impact, aligning with industrial ecology principles. Combined with a low carbon emission binder (i.e., alkali-activated), utilizing agro-waste to produce zero-cement particle boards is a promising method for green construction. Traditionally, particle boards are engineered from wood or agricultural waste products that are pressed and bonded with a binder, such as cement or synthetic resins. However, alternative binders replace cement in zero-cement particle boards to address environmental concerns, such as the carbon dioxide emissions associated with cement production. This study investigated the effects of accelerated aging on the performance of alkali-activated agro-waste particle boards. Accelerated aging conditions simulate natural aging phenomena. Repeated wetting–drying and freezing–thawing cycles increased water absorption and thickness swelling and reduced flexural strength. The thermal performance of the alkali-activated particle boards did not exhibit significant changes. Hence, it was confirmed that agro-waste has a high potential for utilization in producing particle boards provided that the working environment is carefully selected to optimize performance. [ABSTRACT FROM AUTHOR]

The control of pathogens is of great importance to maintaining safe water quality for animal consumption and reducing the spread of pathogens in the environment and throughout the production chain. Titanium dioxide (TiO2) is an attractive nanoparticle for disinfection purposes because it is easy to use, highly effective under UV radiation and cost effective. The goal of this study was to assess the disinfection effectiveness of TiO2-coated materials (high-density polyethylene, HDPE and stainless steel, SS) and UV-A LED light of non-coated materials, and the impacts of temperature and bacteria concentration in disinfection. Three TiO2 composites, two synthesized and one commercial (namely, TiO2, Ag- TiO2 and P25 TiO2), were assessed for their removal photocatalytic efficiency of methylene blue (10 mg/L). P25 TiO2 showed fast photocatalytic efficiency after two hours of treatment, reaching 98% efficiency after 4 h. The immobilization method M1 (fast cured epoxy) of particles in the material showed the best adhesion to substrates (scale = 4 ASTM D 3359) and for TiO2-coated stainless steel in a pre-disinfection test at a temperature of 32.3 °C and efficiency of 55.2%. There were statistically significant differences in disinfection treatments between of TiO2-coated and non-coated materials under the influence of UV-A LED light (p < 0.05) at a control temperature of 26 °C. The resulting disinfection efficiencies for typical trough materials (coated (C) or non-coated (NC) HDPE; and SS) were ranked as follows: SS-C-Light (100%) > SS-Light (81.4%) > HDPE-C-Light (63.9%) > HDPE-Light (51.3%). High ambient temperature and initial bacteria concentration tended to reduce the disinfection efficiency. The presence of TiO2 on the coated surface was confirmed using a scanning electron microscope (SEM) and energy dispersive X-ray microanalyses (EDS). These results demonstrate the disinfection potential of TiO2-coated materials and UV-A LED light, and thus, they should be considered as valuable alternatives to deal with persistent E. coli contamination of cattle troughs. [ABSTRACT FROM AUTHOR]

The passive flux sampling is an economic and easy way to estimate gas emissions from agriculture sources. In the last decade, specific passive flux samplers (PFSs) have been developed to estimate nitrous oxide (N2O) emissions from agriculture sources. Packed with silica gel and zeolite 5A, the PFSs were placed facing the emission source direction close to the ventilation shafts. For validation, air samples were taken at different sampling time during 3 days on two commercial sites. The adsorbed mass of N2O in PFSs was recovered by thermal desorption in the laboratory. Results indicated that the mass of N2O adsorbed in PFSs was from 1.5 to 5.5 μg. A specific adsorption pattern was observed for each sampling. In farm 1, the mass of N2O adsorbed in the PFSs presented a linear behavior as a function of sampling time, and the most determined coefficient values were higher than 0.80. In farm 2, in addition to the sampling time, the N2O concentration and the air flow rate presented an effect on the mass adsorbed in the PFSs. On the other hand, comparison of PFSs versus other techniques indicated that PFSs offer different advantages. However, the selectivity and capacity of the adsorbent bed used need to be improved to enhance the use of PFSs proposed as a tool to estimate N2O emissions. [ABSTRACT FROM AUTHOR]

Simple Summary: An increment pattern in the worldwide egg production, as well as in the farm's capacity in laying hen housing systems, have been observed for the last fifty years. Also, animal welfare has become a subject of interest due to consumer awareness. These issues have introduced new challenges to respond to international markets' demands while ensuring animal welfare and environmental footprint. Cage-free systems have been alternative systems to ensure the well-being of laying hens. Likewise, environmental control strategies have been implemented to improve air quality since airborne contaminants' concentration can be high inside these systems. Thus, the analysis of the effect of these strategies on natural behavior and flock distribution is essential to assess a comprehensive analysis. Four strategies and a control were tested in an experimental cage-free system. Spatial occupancy and animal behaviors were tracked using video recordings. Neither the four environmental strategies nor the control applied in this experiment affected the natural behaviors of hens. However, changes in flock distribution and stress patterns were identified in the treatment with a reduction in litter allowance. This study provides evidence that it is possible to implement strategies to improve air quality without disrupting natural animal behaviors in cage-free systems. Animal welfare concerns have been a challenging issue for producers and international marketing. In laying hen production, cage-free systems (CFS) have been identified as an alternative to ensure the laying hens' well-being. Nevertheless, in CFS, important environmental issues have been reported, decreasing indoor air quality. Environmental control strategies (ECS) have been designed to enhance indoor air quality in CFSs. However, little information exists about the effect of these ECSs on natural animal behaviors. Four strategies and one control were tested in an experimental CFS, previously designed to track behavioral variables using video recordings over seven time-lapses of 1 hour per day. Spatial occupancy (SO) and laying hen behaviors (LHB) were registered. One statistical analysis was applied to evaluate the effect of ECS on SO and LHB using a multinomial response model. Results show lower chances to use litter area within the reduction of litter allowance treatment (T17) (p < 0.05). Neither the four ECSs nor the control implemented in this experiment affected the natural behaviors of the hens. However, stress patterns and high activity were reported in the T17 treatment. This study shows that it is possible to use these ECSs without disrupting laying hens' natural behaviors. [ABSTRACT FROM AUTHOR]

Passive flux samplers (PFSs) packed with adsorbents are used to estimate gaseous emissions. A key condition of their use is maintaining a linear relationship between internal and external air velocities. The performance of PFSs designs depends on the characteristics of the adsorption bed and on the sampler design. The parameters required to enable PFSs to estimate greenhouse (GHG) emissions from agricultural sources were studied. The effect of the particle size of the adsorbent used as collector medium was analyzed theoretically using the Ergun equation. Three orifice plates with 0.5, 0.7 and 1 mm bore diameter were evaluated in order to determine the most appropriate diameter to control air flow through a new passive flux sampler (PFS) prototype while maintaining adequate linearity between internal and external air velocity. The effect of the adsorbent bed thickness (19, 50, 100 and 200 mm) on the internal-external air velocity relationship in the PFS was evaluated. The best performance was obtained using the 0.7 mm orifice plate and an adsorbent bed thickness of 50 mm. Spherical adsorbents with high adsorption capacity are recommended in order to decrease the adsorbent bed thickness and improve sampling performance. A series of experiments showed that the estimated mass flow obtained by the developed PFS was close to the confidence interval of values obtained by direct detection. Thus, the developed PFS can be used as a tool for the estimating of GHG emissions from agricultural sources. [ABSTRACT FROM AUTHOR]

The present study analyzes the effect of parameters that determine the use of the zeolite 5A as collector medium in passive flux samplers (PFS) developed to estimate N 2 O emissions from livestock buildings. The study analyzes the mass of N 2 O collected on the zeolite 5A as a function of gas flow rate (40 and 130 ml/min), inlet mass of N 2 O to the PFS (from 7 to 84 μg), adsorbent mass (4 and 13.6 g), length of the adsorbent bed (1.9 and 10.9 cm), and inlet N 2 O concentration (0.6 and 2 ppmv). The mass of N 2 O collected on the zeolite 5A ranged from 1.24 to 6.19 μg of N 2 O/g of adsorbent, which was mainly affected by inlet N 2 O concentration and mass of adsorbent contained in the PFS. The mass of N 2 O collected presented a significant relationship with the inlet N 2 O concentration and the adsorbent bed. Tests were performed using PFS in a laboratory farm under semi-real conditions. It was found that at sampling time of 1.5 h, the accuracy and precision of PFS was appropriate. Under evaluated conditions, a maximum variation between PFS and direct detection of around 12% was estimated.