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Straw strip burial in saline soil is an effective method for tideland reclamation in China, but optimal forms of straw strips for regulating soil water and salinity remain unclear. An indoor soil column test investigated the water and salt distribution in soil treated with four different straw forms under freshwater irrigation. The treatments included no straw layer (CK), straw stalks arranged longitudinally (T5), horizontally (T25), longitudinally combined horizontally in layers (T25+2.5), and randomly (T2.5). The results showed that compared to CK, T25, T5, and T25+2.5 significantly reduced the infiltration rate of irrigation water, leading to prolonged infiltration times. Wetting front curves under T5, T25+2.5, and T25 exhibited similar inverted "V" shapes, while CK and T2.5 showed fluctuating parallel lines. Water retention in the soil was higher under straw strip treatments (T5, T25, T25+2.5) and straw layer treatment (T2.5) compared to CK after 24 h of the first irrigation. T5 demonstrated the most effective salt removal, surpassing other treatments, with a desalination rate of 97.71%. Additionally, T5 had the highest salt leaching efficiency (SLE) in the 0–20 cm soil layer, recommending it as the optimal form for managing saline soils in crop production due to its simplicity and higher SLE. We found that buried straw strips reduced soil water infiltration rate and wetting front propulsion speed, increased soil water content and enhanced salt leaching efficiency in the saline soil. Our findings provide a basis for developing strategies that improve soil quality and irrigation efficiency, mitigate the effects of salinity on crop production, and ensure food security for a rapidly growing global population. [ABSTRACT FROM AUTHOR]

Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism‐derived carbons as supports for noble‐metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR‐1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm‐associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g−1 and 6.85 A m−2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high‐quality bio‐Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions. [ABSTRACT FROM AUTHOR]

Karstification plays a crucial role in forming magnificent scenery, and storing oil, natural gas, mineral resources, and water. Through the inspiration of karstification, a hierarchical layered double hydroxide (LDH) with funnel-like and cave-like structures (called Karst-LDH) is formed by the dissolution of acrylic acid/water solution. Meanwhile, the results of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) show that Karst-LDH has complicated and interconnected internal pipe networks. The actual maximum phosphate adsorption capacity of Karst-LDH reaches 126.38 mg g−1 due to the unique structures, protonation, ligand exchange, ion exchange, and hydrogen bonding, which is over ten times that of general LDH with a regular hexagonal structure. The results of isotherms and thermodynamics also indicate that Karst-LDH conforms to more heterogeneous and multilayer adsorption with a higher entropy-driven process. Karst-LDH exhibits good selectivity for chloride and nitrate ions. The change in the frontier orbital interaction between phosphate and different LDHs is a significant reason for quick macropore transmission, mesopore interception, and finally, phosphate storage in Karst-LDH. This work provides an efficient way for the design and fabrication of high adsorption performance materials with unique karst-type structures, which can be used for multiple fields potentially. [ABSTRACT FROM AUTHOR]

Dengue virus is an important human pathogen affecting people especially in tropical and subtropical regions. Its genome encodes seven non-structural proteins that are important for viral assembly and replication. Dengue NS2B is a membrane protein containing four transmembrane helices and involved in protein-protein interactions. Its transmembrane helices are critical for location of NS2B on the cell membrane while one cytoplasmic region composed of approximately 40 amino acids serves as a cofactor of viral NS3 protease by forming a tight complex with the N-terminal region of NS3. Here, we report the backbone resonance assignments for a dengue NS2B construct referred to as mini-NS2B containing only the transmembrane regions without NS3 cofactor region in detergent micelles. Mini-NS2B exhibits well-dispersed cross-peaks in the 1H-15N-HSQC spectrum and contains four helices in solution. The available mini-NS2B and its assignment will be useful for determining the structure of NS2B and identifying small molecules binding to the transmembrane regions. [ABSTRACT FROM AUTHOR]

Six novel keratin-based fluorescent hierarchical porous hydrogels, pure keratin (FK), keratin-seaweed (FK-SP), keratin-chitosan (FK-CS), and keratin-rhodamine B (FK-Rh B) with three-dimensional (3D) interconnected network structures have been prepared via a one-pot crosslinking method. The green-red dual emissions of the FK-SP and FK-Rh B hydrogels were observed under a single-wavelength excitation. [ABSTRACT FROM AUTHOR]

In order to effectively improve the wear and corrosion resistance of the inner wall of the beverage filling machine, a kind of strengthened ceramic coating was prepared by the plasma spraying technology. Under the conditions of different working current, spraying distance and spraying speed, the changing laws of the characteristics such as arc pressure, coating roughness and porosity were tested and analyzed. The coating samples with different thicknesses were prepared, and their morphology, micro hardness and wear rate were measured. The influence mechanism of spraying heat source on mechanical properties of the coating was studied. By placing the coating samples in weak acid (acetic acid solution), weak alkali (soda water solution), and 80 °C constant temperature environment for corrosion treatment, the wear morphology and principle of the coating were studied. The research shows that ceramic coatings can increase the surface hardness of the base material by 43.4%, reduce the wear rate by 22.6%, ensure the roughness deviation before and after corrosion is less than 5%, significantly improve mechanical properties and corrosion resistance, and have strong adaptability to weak acid, weak alkali, and variable temperature environments. The research provides reference for the development of surface strengthening technology in food machinery. [ABSTRACT FROM AUTHOR]

Pile driving in marine engineering causes a vibration response in the surrounding soil and adjacent piles, which may affect the safety of adjacent structures supported by the pile foundation and the internal equipment of the adjacent structures. Therefore, for the safe completion of a project, it is of great significance to study the ground and the pile vibrations induced by pile driving. Based on measurement data from a Rudong wind farm engineering in Jiangsu Province, a numerical model of the vibration response induced by pile driving was established. Based on various methods of calculating pile driving loading, the influence of pile driving loading characteristics on the vibration response was analyzed. Furthermore, the influence of pile driving on the acceleration of the ground and adjacent piles was studied, including the impacts of the distance between the driving pile, the existing pile and the driving depth. The results show that the acceleration of the ground has a good linear relationship with the distance in the logarithmic coordinate system, and the acceleration of the existing pile attenuates with an increasing driving depth of the driving pile. A simplified evaluation method for the peak acceleration response of adjacent sites impacted by pile driving was proposed, which provides a reference for ocean engineering construction in the Huangsha Ocean area of China. [ABSTRACT FROM AUTHOR]