Search Results (68)

Currently, the visual study of the structure of building materials and products is gradually supplemented by intelligent algorithms based on computer vision technologies. These algorithms are powerful tools for the visual diagnostic analysis of materials and are of great importance in analyzing the quality of production processes and predicting their mechanical properties. This paper considers the process of analyzing the visual structure of non-autoclaved aerated concrete products, namely their porosity, using the YOLOv11 convolutional neural network, with a subsequent prediction of one of the most important properties—thermal conductivity. The object of this study is a database of images of aerated concrete samples obtained under laboratory conditions and under the same photography conditions, supplemented by using the author’s augmentation algorithm (up to 100 photographs). The results of the porosity analysis, obtained in the form of a log-normal distribution of pore sizes, show that the developed computer vision model has a high accuracy of analyzing the porous structure of the material under study: Precision = 0.86 and Recall = 0.88 for detection; precision = 0.86 and recall = 0.91 for segmentation. The Hellinger and Kolmogorov–Smirnov statistical criteria, for determining the belonging of the real distribution and the one obtained using the intelligent algorithm to the same general population show high significance. Subsequent modeling of the material using the ANSYS 2024 R2 Material Designer module, taking into account the stochastic nature of the pore size, allowed us to predict the main characteristics—thermal conductivity and density. Comparison of the predicted results with real data showed an error less than 7%. Full article

Phalaenopsis is a widely cultivated ornamental plant of considerable economic value worldwide. However, traditional growing medium, sphagnum moss, is limited and non-renewable. It also decomposes slowly and is prone to environmental issues. Therefore, there is an urgent need to identify more environmentally friendly and efficient alternatives. Biochar, a sustainable material with excellent physical and chemical properties, has been recognized as an effective promoter of plant growth. In this study, we investigated the influence of biochar derived from three raw materials (corn straw, bamboo, and walnut) mixed1 with coconut shell at ratios of 1:2, 1:10, and 4:1, on the growth of Phalaenopsis ‘Big Chili’. Over a 150-day controlled experiment, we evaluated multiple growth parameters, including plant height, crown width, total root length, total projected area, total surface area, and root volume. Compared to the traditional growing medium, the optimal biochar-coconut shell mixture (maize straw biochar: coconut shell = 1:2) increased plant height and crown width by 7.55% and 6.68%, respectively. Root metrics improved substantially, with total root length increasing by 10.96%, total projected area by 22.82%, total surface area by 22.14%, and root volume by 38.49%. Root biomass in the optimal treatment group increased by 42.47%, while aboveground and belowground dry weights increased by 6.16% and 77.11%, respectively. These improvements were closely associated with favorable substrate characteristics, including low bulk density, high total and water-holding porosity, moderate aeration, and adequate nutrient availability. These findings demonstrate that substrate characteristics critically influence plant performance and that biochar–coconut shell mixtures, particularly at a 1:2 ratio, represent a viable and sustainable alternative to sphagnum moss for commercial cultivation of Phalaenopsis. Full article

Livestock production systems can negatively affect soil structure, resulting in negative changes in physical–hydraulic properties, compromising soil functioning and productivity. This research aimed to evaluate the effects of rotational silvopastoral systems on soil physical–hydraulic functioning in their second year of implementation. The study was performed under Oxisol soil with a loamy sand texture in Southeast Brazil. We considered four grazing systems: an intensive silvopastoral system with Panicum maximum in consortium with Leucaena leucocephala (ISPS + L), an intensive silvopastoral system with Panicum maximum in consortium with Tithonia diversifolia (ISPS + T), an silvopastoral system with Panicum maximum (SPS) with tree row (TRs), and open pasture under a rotational grazing system with Panicum maximum (OP). The treatments ISPS + L, ISPS + T, and SPS had tree rows (TRs) every 20 m composed of Khaya ivorenses, Leucaena leucocephala, Eucalyptus urograndis, Acacia mangium, and Gliricidia sepium. Nine physical–hydraulic indicators were evaluated in the first 0.40 m of depth: bulk density (Bd), total porosity (TP), macroporosity (MaP), microporosity (MiP), field capacity (FC), permanent wilting point (PWP), available water content (AWC), total soil aeration capacity (ACt), and S-index. The soil physical–hydraulic properties were sensitive to the effects of the livestock systems. The use of silvopastoral systems in consortium with grass (ISPS + L and ISPS + T) allowed for better soil water retention, resulting in higher FC and AWC than the OP, SPS, and TR. The indicators Bd, ACt, MaP, FC, MiP, and S-index presented the greatest variance; however, FC, ACt, MaP, and MiP enabled the greatest differentiation among systems. Therefore, these properties are important in studies on soil physical quality since they provide information about the soil porous status and its ability to retain water and exchange soil air and gases. Therefore, enhancing the physical–hydraulic attributes of the soil in silvopastoral systems with shrub species is crucial for ensuring long-term productive sustainability and strengthening environmental resilience against future climate challenges. Full article

Compaction leads to reduced crop yields, as the soil structure is destroyed. As soil structures respond differently to different degrees of compaction stress, early warnings for the risk of soil compaction caused by agricultural machinery need to be provided based on changes to the soil structure. In this study, we quantified the changes in the aeration porosity, aggregate mean weight diameter, structure coefficient, and cone index of different soil layers in response to compaction stress under different tyre axle weights (7.0 kN, 11.5 kN, 15.8 kN, and 20.4 kN) to analyse the risk of soil compaction in the topsoil layer (0–25 cm). The results showed that the compaction stresses that led to significant changes in soil structure in the 0–5 cm, 5–10 cm, 10–15 cm, and 15–20 cm soil layers were 130 kPa, 156 kPa, 111 kPa, and 103 kPa, respectively, and were significantly greater than the precompression stress of the soil in each layer. This finding proves that the changes in soil volume and structure caused by compaction are significant but not exactly equivalent; moreover, a threshold past which the stress caused by compaction results in soil structure failure still exists. Under 180 kPa of surface contact stress, the soil cone index, aeration porosity, aggregate mean weight diameters, and structure coefficient of the 0–5 cm and 5–10 cm soil layers gradually moved closer to the soil parameter levels of the subsoil layer before compaction. We suggest that the response of the soil structure to compaction stress proceeds along three stages, elastic deformation, plastic deformation without structure failure, and soil structure failure, within which soil structure failure stress and precompression stress are the two key threshold stresses. This study provides a more reliable theoretical basis upon which field managers can warn of soil compaction risk. Full article

Effective coal slurry water solid–liquid separation is indispensable for the recycling and sustainable development of coal resources. The interaction between bubble and coal particles plays a critical role in the process of dewatering for clean coal. In this study, we firstly conducted a comprehensive investigation of the impact of froth on the interactions between coal particles by rheological measurement and particle aggregation behavior. Furthermore, the macroscopic dewatering performance of coal slurry in the presence of froth and its microscopic cake structure were investigated using the filtration test and X-ray microtomography (CT). It was found that the interaction between coal particles in the presence of froth was enhanced as a result of the dynamic shear value, combined with the large floc size and compact structure, which led to a higher cake moisture and higher filtration velocity. The CT results indicated that the enhanced interaction of particles in the presence of froth also led to a dense microstructure of the filter cake. The porosity of the filter cake decreased to 2.05% when the aeration time increased from 0 s to 90 s, the throat radius in the filter cake was reduced to 1.32 μm, and the number of throat passages was reduced to one third. Multiple blind pores and low coordination numbers led to a poor connectivity of the pore network and high moisture content. Full article

Under the one-season-a-year cropping pattern in Northeast China, continuous cropping is one of the main factors contributing to the degradation of black soil. Previous studies (on maize–soybean, maize–peanut, and maize–wheat intercropping) have shown that intercropping can alleviate this problem. However, it is not known whether intercropping is feasible for maize and rice under dry cultivation, and its effects on yield and soil fertility are unknown. A three-year field-orientation experiment was conducted at Jilin Agricultural University in Changchun city, Jilin Province, China, consisting of three cropping regimes, namely rice under dry cultivation–maize intercropping (IRM), sole rice under dry cultivation (SR), and sole maize (SM). All straw was fully returned to the field after mechanical harvesting. Rice under dry cultivation–maize intercropping with a land-equivalent ratio of 1.05 (the average of three years values) increased the total yield by 8.63% compared to the monoculture system. The aggressivity (A), relative crowding coefficient (K), time–area-equivalent ratio (ATER), and competition ratio (CR) value were positive or ≥1, also indicating that the rice under dry cultivation–maize intercropping had a yield advantage of the overall intercropping system. This is because the intercropped maize root length density (RLD) increased by 33.94–102.84% in the 0–40 cm soil layer, which contributed to an increase in the soil porosity (SP) of 5.58–10.10% in the 0–30 cm soil layer, an increase in the mean weight diameter of soil aggregates (MWD) of 3.00–15.69%, an increase in the geometric mean diameter of soil aggregates (GMD) of 8.16–26.42%, a decrease in the soil bulk density (SBD) of 4.02–7.35%, and an increase in the soil organic matter content (SOM) of 0.60–4.35%. This increased the water permeability and aeration of the soil and facilitated the absorption of nutrients and water by the root system and their transportation above ground, and the plant nitrogen, phosphorus, and potassium accumulation in the intercropping system were significantly higher than that in monoculture treatment, further promoting the total yield of intercropping. This suggests that rice under a dry cultivation–maize intercropping system is feasible in Northeast China, mainly because it promotes belowground root growth, improves the soil environment, and increases the total yield of intercropping. Full article

Time-lapse ground-penetrating radar (GPR) surveys, combined with automated infiltration experiments, provide a non-invasive approach for investigating the distribution of infiltrated water within the soil medium and creating three-dimensional images of the wetting bulb. This study developed and validated an experimental protocol aimed at quantifying and visualizing water distribution fluxes in layered soils under both unsaturated and saturated conditions. The 3D images of the wetting bulb significantly enhanced the interpretation of infiltration data, enabling a detailed analysis of water movement through the layered system. We used the infiltrometer data and the Beerkan Estimation of Soil Transfer parameters (BEST) method to determine soil capacitive indicators and evaluate the physical quality of the upper soil layer. The field survey involved conducting time-lapse GPR surveys alongside infiltration experiments between GPR repetitions. These experiments included both tension and ponding tests, designed to sequentially activate the soil matrix and the full pore network. The results showed that the soil under study exhibited significant soil aeration and macroporosity (represented by AC and p_MAC), while indicators related to microporosity (such as PAWC and RFC) were notably low. The RFC value of 0.55 m³ m⁻³ indicated the soil’s limited capacity to retain water relative to its total pore volume. The PAWC value of 0.10 m³ m⁻³ indicated a scarcity of micropores ranging from 0.2 to 30 μm in diameter, which typically hold water accessible to plant roots within the total porosity. The saturated soil hydraulic conductivity, K_s, values ranged from 192.2 to 1031.0 mm h⁻¹, with a mean of 424.4 mm h⁻¹, which was 7.9 times higher than the corresponding unsaturated hydraulic conductivity measured at a pressure head of h = −30 mm (K₋₃₀). The results indicated that the upper soil layer supports root proliferation and effectively drains excess water to the underlying limestone layer. However, this layer has limited capacity to store and supply water to plant roots and acts as a restrictive barrier, promoting non-uniform downward water movement, as revealed by the 3D GPR images. The observed difference in hydraulic conductivity between the two layers suggests that surface ponding and overland flow are generated through a saturation excess mechanism. Water percolating through the soil can accumulate above the limestone layer, creating a shallow perched water table. During extreme rainfall events, this water table may rise, leading to the complete saturation of the soil profile. Full article

To investigate the long-term effects of organic manure on soil macro-porosity and nutrient stoichiometry in greenhouse production, we studied the physical and chemical properties of soils under different vegetable systems in Jiangsu Province. These systems included organic greenhouse vegetable (OGV), organic open-field vegetable (OFV), conventional greenhouse vegetable (CGV), and conventional open-field vegetable (CFV), with rice–wheat rotation (RWR) soils used as a reference.The results showed that, compared to conventional systems, organic vegetable production increased soil macro-porosity, soil organic carbon (SOC), and total nitrogen (TN) content, as well as C:N, C:P, and N:P, particularly in the tilled layer. SOC, TN, and total phosphorus (TP) levels increased rapidly during the first 14 years of OGV cultivation, followed by a decline. SOC, TN, and stoichiometric ratios were significantly positively correlated with soil macro-porosity. The study suggests that converting RWR to OGV does not degrade soil aeration, and long-term application of organic manure positively impacts nutrient retention in the tilled layer, although the effects are time- and depth-dependent. The study highlights the potential of long-term organic manure application to improve soil aeration and nutrient balance in OGV, underscoring the importance of optimizing fertilizer management in intensive agriculture to enhance soil quality and crop yield. Full article

Tourist trampling is a serious disturbance affecting the soil structure and microbial community in forests. However, it is still unclear whether the response of soil microorganisms to trampling is attributed to the alterations in soil physical (soil bulk density and total porosity) or soil chemical (total nitrogen and soil organic carbon) properties. To determine the response and mechanism of soil microbial community composition to tourist trampling, we conducted a field experiment including four levels of trampling intensity (control, mild, moderate, and severe) at the Baotianman forest ecotourism area. With increasing trampling intensity, soil bulk density showed a substantially increasing pattern, whereas soil total porosity, total nitrogen, and soil organic carbon showed a decreasing trend. Compared to the insignificant change under mild trampling, moderate and severe trampling significantly decreased soil bacterial PLFAs (phospholipid fatty acids) by 46.6% and 57.5%, and fungal PLFAs by 36.3% and 61.5%, respectively. Severe trampling showed a significantly negative effect (−4.37%) on the proportion of soil bacterial PLFAs. Changes in soil bulk density and porosity induced by trampling, rather than total nitrogen and soil organic carbon, played a greater role in regulating soil microbial community composition. These findings suggest that soil microbial community composition and biomass are significantly influenced by the changes in soil texture and aeration conditions caused by tourist trampling. Full article

Biochar is regarded as a soil improvement material possessing superior physical and chemical properties that can effectively enhance plant growth. However, there exists a paucity of research examining the efficacy of biochar in supplanting traditional materials and its subsequent impact on the growth of Ardisia crenata, which is currently domesticated as fruit ornamentals. In this study, the mechanism of biochar’s effect on Ardisia crenata was analyzed by controlled experiments. For 180 days, their growth and development were meticulously assessed under different treatments through the measurement of various indices. Compared with the references, the addition of biochar led to an average increase in soil nutrient content, including a 14.1% rise in total nitrogen, a 564.1% increase in total phosphorus, and a 63.2% boost in total potassium. Furthermore, it improved the physical and chemical properties of the soil by reducing soil bulk density by 6.2%, increasing total porosity by 6.33%, and enhancing pore water by 7.35%, while decreasing aeration porosity by 1.11%. The growth and development of Ardisia crenata were better when the appending ratio of biochar was in the range of 30% to 50%, with the root parameters, such as root length, root surface area, and root volume, 48.90%, 62.00%, and 24.04% higher to reference. At the same time, the biomass accumulation of roots in the best group with adding biochar also increased significantly (55.80%). The addition of biochar resulted in a significant improvement in the content of chlorophyll a and chlorophyll b (1.947 mg g⁻¹) and the net photosynthetic rate (5.6003 µmol m⁻² s⁻¹). This study’s findings underpinned the addition of biochar in soil improvement and plant response. Therefore, biochar can favor the cultivation and industrial application of Ardisia crenata in the future, leading to an efficient and environmentally friendly industrial development. Full article

In spite of the demonstrated efficacy of basalt stone powder as a cost-effective and readily available additive in enhancing the mechanical properties and durability of ordinary-weight concrete, its application in Structural Lightweight Concrete (SLWC) remains unexplored. This study introduced a mixing design for SLWC incorporating Light Expanded Clay Aggregates (LECAs) and basalt stone powder with a subsequent evaluation of its strength and durability characteristics. The experimental procedure involved creating various samples, considering differing proportions of cement, water, basalt stone powder, sand, LECA, superplasticizer, and aerating agent. The compressive strength and density of the 28-day-cured concrete specimens were determined. An optimal SLWC with a compressive strength of 42 MPa and a density of 1715 kg/m³ was identified. The flexural and tensile strength of the optimal SLWC exceeded those of ordinary-weight concrete by 6% and 3%, respectively. Further evaluation revealed that the optimal SLWC exhibited 1.46% water absorption and an electrical resistivity of 139.8 Ohm.m. Notably, the high porosity of LECA contributed to the low durability of SLWC. To address this, cost-effective external coatings of emulsion and fiberglass were applied to enhance the durability of the SLWC. Four coating scenarios, including one-layer bitumen, two-layer bitumen, three-layer bitumen, and three-layer bitumen with fiberglass, were investigated. The measurements of electrical resistance and compressive strength revealed that the use of three layers of emulsion bitumen and fiberglass improved the durability of the concrete by over 90% when the SLWC was exposed to severe chloride attack. Consequently, the durability of the SLWC with an external coating surpassed that of ordinary-weight concrete. Full article

The purpose of this research is to investigate the utilization potential of recycled powder made from spent coffee grounds (SCGs) and aerated concrete blocks (ACBs) in green-growing concrete. The green-growing concrete is prepared using ACB powder and SCG ash as raw materials instead of 5%, 15%, and 25% and 5%, 10%, and 15% cement, respectively. Then, the two raw materials are compounded with the optimal content. The compressive strength and alkalinity of green-growing concrete at 7d and 28d and the frost resistance after 25 freeze–thaw cycles at 28d are studied. The results showed that the optimum content of ACB powder and SCG ash was 5%. Replacing 5% cement with recycled powder could improve the strength of concrete. The alkalinity of concrete containing ACB powder gradually increased, while the alkalinity of concrete containing SCG ash gradually decreased. The alkalinity of ACB-SCG powder was lower than that of ACB powder but slightly higher than that of SCG ash. The frost resistance of concrete containing ACB powder decreased gradually, and the frost resistance of concrete containing SCG ash increased first and then decreased greatly. The frost resistance of ACB-SCG powder could neutralize that of ACB powder and SCG ash. Full article

The purpose of this work was to explore the feasibility of replacing all or part of peat with composted green waste (CGW) for vinca (Catharanthus roseus (L.) G. Don) and zinnia (Zinnia elegans Jacq.) cultivation. Seven different growing media were prepared as follows (volume/volume): T1, 100% CGW; T2, 80% CGW + 20% peat; T3, 60% CGW + 40% peat; T4, 50% CGW + 50% peat; T5, 40% CGW + 60% peat; T6, 20% CGW + 80% peat; and T7, 100% peat. In the course of the experiment, the physicochemical properties of the seven media were analyzed, and the growth of vinca and zinnia was determined. Studies showed that replacing peat completely or partially with CGW could significantly enhance the nutrient content, bulk density, water-holding capacity, total porosity, aeration porosity, water-holding porosity, organic matter, pH, and electrical conductivity of growing media. In comparison with what observed with T7 (control), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), root dry weight (RDW), plant height (HP), root length (RL), flower number (FN), total chlorophyll, and the content of chlorophyll a, chlorophyll b, and carotenoids in the leaves of vinca cultivated under T5 conditions increased by 36%, 34%, 84%, 27%, 34%, 25%, 157%, 62%, 60%, and 33%, respectively; SFW, SDW, RFW, RDW, HP, RL, FN, total chlorophylls, and the content of chlorophyll a, chlorophyll b, and carotenoids in the leaves of zinnia increased by 341%, 296%, 365%, 302%, 206%, 93%, 180%, 56%, 49%, 67%, 110%, respectively. Full article

The vast majority of different waste building units have negative environmental impacts around the world. Crushed building units can be recycled and utilized in the concrete industry to solve these problems and maintain natural resources. This study investigated the feasibility of employing crushed autoclaved aerated concrete (CAAC) and crushed clay brick (CCB) as a lightweight aggregate (LWA) to fabricate environmentally friendly recycled lightweight concrete (LWC). In addition, a lightweight expanded clay aggregate (LECA) was also used as an LWA, namely to study how the high porosity of an LWA can adversely affect the properties of LWC. Through the experimental program, all types of LWAs were pre-treated and strengthened with two cementitious grouts, and then the performance of the produced LWC was assessed by determining the slump of fresh concrete, the dry density, the unconfined compressive strength, and the splitting tensile strength at ages of 3, 7, 28, and 56 days. The laboratory results revealed that both CCB and CAAC can be reused as full substitutions for normal-weight coarse aggregate to manufacture LWC with appropriate properties. The obtained data show that the properties of an LECA, CCB, and CAAC were improved, and the porous structure can be strengthened by pre-treatment and coating with grouts. In the same way, the mechanical performance of produced LWC is also enhanced. Full article

Farming systems should be sustainable in order to protect the soil from diseases and pests while preserving the environment and generating economic and social benefits. The use of biological products can help reduce the negative characteristics that damage the soil and increase the likelihood of healthy plant growth. Therefore, the aim of this study was to investigate the influence of biotreatment on the physical properties of different soils and substrates as well as strawberry (Fragaria × ananassa) yield. In the laboratory trials, “Asia” strawberries were grown one by one in special containers on different soils and substrates: loam (L), clay (C), sandy loam (SL), compost soil (CS), and coconut fiber (CF). The soils and substrates were treated once a week with a biological product based on molasses and magnesium sulfate and fertilized with a complex fertilizer: NPK11-11-21 + K₂O + Mg, S, B, Cu, Fe, Mn, Mo, and Zn, enriched with potassium. Soil and substrate temperature, moisture, density, total porosity, aeration porosity, electrical conductivity as well as strawberry yield were measured in the test containers containing the plants. Studies have shown that the use of bioproducts does not significantly improve the physical properties of soils and substrates. However, the trend of the results shows that using the bioproduct for a longer period of time would have a greater effect on the physical properties of the soils and substrates, especially for peat-based substrates prepared for greenhouse use. Berry yields increased significantly (46.6% and 100%) with biotreatment in the CS and CF variants. Full article