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This study investigated the impact of soil-structure interaction on the seismic performance of masonry ancient pagodas. For this purpose, shaking table tests were conducted using a pagoda model to simulate the seismic damage patterns and damage evolution of the pagoda under conditions considering soil-structure interaction. Additionally, numerical models were established for both rigid foundation conditions and soil-structure interaction conditions, validated through dynamic characteristic testing and shaking table experiments. The results indicated that under soil-structure interaction conditions, the top of the pagoda cracked first, with severe damage occurring on the second floor. The damage characteristics of the pagoda differ significantly from those observed under rigid foundation conditions. The numerical simulations effectively predicted the dynamic response of the structure. Compared to the results obtained under rigid foundation conditions, the acceleration of the upper structure decreased by 34 %-79 % after considering soil-structure interaction, while the horizontal displacement at the top of the pagoda increased by 1.4 mm-7.8 mm. The inter-story displacement angle of the first floor was amplified by 3-10 times, with significant degradation of stiffness, while the impact on the stiffness of the top floor was relatively minor. The tensile damage to the pagoda was more pronounced, and the damage area shifted from the first floor to the second floor. The findings provide important references for the seismic assessment of masonry ancient pagodas.

期刊论文 2025-08-01 DOI: 10.1016/j.jobe.2025.112719

The negative ramifications of invasive alien species (IAS) are considered the second-most cause of biodiversity extinction and endangerment after habitat modification. IAS movements are mainly anthropogenically driven (e.g., transport of shipping containers) and require fast detection to minimize damage and cost. The present study is the first to use molecular biosurveillance of international shipping containers to detect IAS and regulated species identification in Canada. Thirty-eight samples were collected from debris (soil, stems, seeds, individual specimens) found in containers arriving in Canada. A multi-marker approach using COI, ITS, ITS2, and 16S was used to identify four main taxonomic groups: arthropods, fungi, plants, and bacteria, respectively. Eleven IAS species were identified via metabarcoding based on environmental DNA samples, including two arthropods, six fungi, two plants, and one bacteria. The origin of the eDNA detected from each species was linked to their native distribution and country of origin, except for Lymantria dispar. Four physical specimens were also collected from shipping container debris and DNA barcoded, identifying three non-regulated species (two arthropods and one fungus). Altogether, these results demonstrate the importance of integrating molecular identification into current toolkits for the biosurveillance of invasive alien species and provide a set of validated protocols ready to be used in this context. Additionally, it reaffirms international shipping containers as a pathway for multiple invasive aliens and regulated species introduction in Canada. It also highlights the need to establish regular and effective molecular biosurveillance at the Canadian border to avoid new or recurrent invasions. Las ramificaciones negativas de las especies ex & oacute;ticas invasoras (EEI) se consideran la segunda causa de extinci & oacute;n y peligro de la biodiversidad despu & eacute;s de la modificaci & oacute;n del h & aacute;bitat. Los movimientos de EEI son impulsados principalmente por causas antropog & eacute;nicas (por ejemplo, transporte de contenedores de env & iacute;o) y requieren una detecci & oacute;n r & aacute;pida para minimizar da & ntilde;os y costos. El presente estudio es el primero en utilizar biovigilancia molecular de contenedores de env & iacute;o internacionales para detectar EEI y la identificaci & oacute;n de especies reguladas en Canad & aacute;. Se recolectaron treinta y ocho muestras de material (tierra, tallos, semillas, espec & iacute;menes individuales) encontrados en contenedores que llegaron a Canad & aacute;. Se utilizaron m & uacute;ltiples marcadores moleculares, COI, ITS, ITS2 y 16S, para identificar cuatro grupos taxon & oacute;micos principales: artr & oacute;podos, hongos, plantas y bacterias, respectivamente. Se identificaron once especies de EEI mediante matabarcoding basado en ADN ambiental, incluidos dos artr & oacute;podos, seis hongos, dos plantas y una bacteria. El origen del ADN ambiental detectado de cada especie estuvo vinculado a su distribuci & oacute;n nativa y pa & iacute;s de origen, excepto Lymantria dispar. Tambi & eacute;n se recolectaron cuatro espec & iacute;menes en los contenedores de env & iacute;o y se analizaron mediante c & oacute;digo de barras de ADN, identificando tres especies no reguladas (dos artr & oacute;podos y un hongo). En conjunto, estos resultados demuestran la importancia de integrar la identificaci & oacute;n molecular dentro de las herramientas actuales para la biovigilancia de especies ex & oacute;ticas invasoras y proporcionan un conjunto de protocolos validados listos para ser utilizados en este contexto. Adem & aacute;s, reafirma que los contenedores de transporte internacional son una v & iacute;a para la introducci & oacute;n de m & uacute;ltiples especies ex & oacute;ticas invasoras y especies reguladas en Canad & aacute;. Tambi & eacute;n destaca la necesidad de establecer una biovigilancia molecular peri & oacute;dica y eficaz en la frontera canadiense para evitar invasiones nuevas o recurrentes.

期刊论文 2025-03-01 DOI: 10.1007/s10530-025-03549-w ISSN: 1387-3547

Many single-use plastic (SUP) options made of synthetic polymers, bio-based materials, and blends of both are available in the market and used in large quantities. The disintegration of eleven commercial SUP, marketed in Mexico as cups and plates, was investigated in an aerobic home compost environment at a laboratory scale over 180 days. An evaluation of chemical changes, surface morphology, and thermal and mechanical properties was conducted to ascertain the original composition of SUP and the progression of disintegration in samples that are challenging to clean from soil contamination. Furthermore, the impact of residual compost on barley (Hordeum vulgare) plant growth and its correlation with the leaching of heavy metals were explored. The bio-based SUP, but not those made of expanded polystyrene foam, showed a correlation between the disintegration degree (measured by weight loss into particles <2 mm) and a decrease in functional groups (observed by FT-IR), mechanical-thermal stability loss, and surface wear over disintegration time. For instance, the highest disintegration at 180 days was approximately 70 % for wheat bran and palm leaf plates, followed by wheat plates and cellulose-PLA cups (60 %). In addition to the components listed by the manufacturers, the FT-IR and DSC analysis revealed the presence of polyethylene and polypropylene in cellulose cups and sugarcane plates. These components, impede disintegration but contribute to preserving thermal resistance and hydrophobicity during utilization. Compost derived from expanded polystyrene foam SUP, with 90 days of disintegration, was rich in zinc and chromium and significantly decrease in the root length of the barley plant compared to the control. This demonstrates the necessity of considering the impact of the leaching of additives and secondary microplastics into the environment.

期刊论文 2024-12-01 DOI: 10.1016/j.polymdegradstab.2024.111071 ISSN: 0141-3910

In this study, the dynamic response of a semi-buried steel vessel under a near-surface explosion shock load was investigated through full-scale model tests. A three-dimensional precise numerical simulation model of the semi-buried steel vessel structure was established, and the dynamic response and damage consequences under different load conditions were analyzed. The influence of the thickness of corrugated steel on the dynamic damage and antiknock properties of the structure was studied. The results show that the weak part of the rectangular steel vessel structure is mainly located at the connection between the blast-facing panel and the beam column under near-surface explosion conditions. The peak stress and displacement of the blasting surface decrease with the increase in the horizontal angle of the incident wave, whilst/while increase with the height of the explosion. Under the same explosive yield, the main failure mode of the structure is the tearing of the plate and beam under plastic deformation. Increasing the thickness of the corrugated steel can significantly restrain the plastic deformation and acceleration of the plate. When the thickness is increased from 2 mm to 6 mm, the antiknock performance is significantly improved. However, when the thickness is increased from 6 mm to 8 mm, the improvement in antiknock performance slows down. Increasing the height of the enclosing soil can also effectively improve the explosion-proof performance of the structure, with full burial providing the best effect. The research results provide a theoretical basis for the application of rectangular steel vessel structures in the field of protection engineering.

期刊论文 2024-12-01 DOI: 10.1016/j.cscm.2024.e03518 ISSN: 2214-5095

The microplastics and organic additives formed in routine use of plastic takeaway food containers may pose significant health risks. Thus, we collected plastic containers made of polystyrene, polypropylene, polyethylene terephthalate, polylactic acid and simulated two thermal usages, including hot water (I) and microwave treatments (M). Nile Red fluorescence staining was developed to improve accurate counting of microplastics with the aid of TEM and DLS analysis. The quantity of MPs released from thermal treatments was determined ranging from 285.7 thousand items/cm(2) to 681.5 thousand items/cm(2) in containers loaded with hot water with the following order: IPS>IPP>IPET>IPLA, while microwave treatment showed lower values ranging from 171.9 thousand items/cm(2) to 301.6 thousand items/cm(2). In vitro toxicity test using human intestinal epithelial Caco-2 cells indicated decrease of cell viability in raw leachate, resuspended MPs and supernatants, which might further lead to cell membrane rupture, ROS production, and decreased mitochondrial membrane potential. Moreover, the leachate inhibited the expression of key genes in the electron transport chain (ETC) process, disrupted energy metabolism. For the first time, we isolate the actually released microplastics and organic substances for in vitro toxicity testing, and demonstrate their potential impacts to human intestine.

期刊论文 2024-08-15 DOI: 10.1016/j.jhazmat.2024.134866 ISSN: 0304-3894

In response to the decline of Central European spruce monocultures driven by various factors, the Demonstration Object of Reconstruction of Spruce Forests (DORS) was established in Hus & aacute;rik locality, Javorn & iacute;ky Mts., northwestern Slovakia. The area includes the Hus & aacute;rik trial site, where the applicability and efficiency of different artificial regeneration methods are studied. The trial was established on a 24-ha area cleared following the outbreak of spruce bark beetles in 2011. Its altitude is 800 m a.s.l., aspect NW, slope 30%, the soil is Ranker on the soft flysch sandstone bedrock. Our study covered 4 conifers - Norway spruce (spruce), European larch (larch), silver fir (fir), and Douglas fir (doug fir). Each species was regenerated using 4 different approaches: planting of commercial bareroot transplants (BR), planting of container transplants (CON), direct seeding (DS) and vegetative cell seeding using seed shelters (VCS). Results concerning the nine-year development of transplants and seedlings, along with the calculation of cost-efficiency, are presented. As to the species, BR and CON transplants of spruce and larch reached the best survival and height. The DS larch was the most cost-efficient method of establishment of a successfully established plantation (survival > 50%; stem height > 2/3 of the weed height; ratio of damaged individuals < 50%) with a total cost of 2 372 EURha(-1). On the contrary, the slow initial growth of fir and Douglas fir and their extensive damage resulted in the incomparably higher cost of establishment of their successfully established plantation, such as 4 980 EURha(-1) for five-years-old BR fir transplants. Our findings documented that current efforts related to the restoration of salvage-felled clearings remained difficult, especially in the case of introduction or reestablishment of coniferous tree species more vulnerable to open site conditions.

期刊论文 2024-01-01 DOI: 10.17221/1/2024-JFS ISSN: 1212-4834

Decomposition is a key process in carbon and nutrient cycling. However, little is known about its response to altered winter soil temperature regimes in boreal forests. Here, the impact of soil frost on cellulose decomposition over 1 yr and soil biotic activity (bait-lamina sticks) over winter, in spring, and in summer was investigated using a long-term (9-yr) snow-cover manipulation experiment in a boreal Picea abies forest. The experiment consisted of the treatments: snow removal, increased insulation, and ambient control. The snow removal treatment caused longer and deeper soil frost (minimum temperature - 8.6 degrees C versus - 1.4 degrees C) at 10 cm soil depth in comparison with control, while the increased insulation treatment resulted in nearly no soil frost during winter. Annual cellulose decomposition rates were reduced by 46% in the snow removal manipulation in comparison with control conditions. Increased insulation had no significant effect on decomposition. The decomposition was mainly driven by microorganisms, as no significant difference was observed for containers enclosed with a 44-mu m and a 1-mm mesh. Soil biotic activity was slightly increased by both the snow removal and the increased insulation treatment in comparison with control conditions over winter. However, this effect disappeared over spring and summer. We conclude that soil frost can have strong effects on decomposition in boreal ecosystems. Further studies should investigate to which degree the observed reduction in decomposition due to reduced snow cover in winter slows or even offsets the expected increase in decomposition rates with global warming.

期刊论文 2013-09-01 DOI: 10.4141/CJSS2012-025 ISSN: 0008-4271
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