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Viscosity of alumina slurry is a key factor affecting the quality of ceramics formed by stereo photolithography, but it is closely related to the resin distribution ratio, dispersant content, plasticizer content and solid content. Most researchers utilize the single factor method to study the composition and ratio of the slurry. In this study, orthogonal experimental design and back propagation artificial neural networks methods were combined to solve the optimisation problem of multi-objective and multi-factor influence on alumina slurry performances. The results of optimal composition and content allocation were achieved by back propagation artificial neural networks and experimental testing. It was shown that the optimal conditions are: resin composition HDDA : PPTTA = 4 : 1, DS-165A dispersant content of 3.86wt.%, PEG plasticiser amount of 3.5wt.% and the solid content of 75.74wt.%. The predicted optimal viscosity value was 8787mPa•s and the shrinkage rate could reach 14.57%. The optimal values of viscosity and shrinkage were consistent with the experimental results, the viscosity and shrinkage errors were only 4.06% and 3.856%, respectively. The average density and bending strength of the sintered samples were 3.979 ± 0.005 g/cm3 and 365 ± 61MPa, respectively. According to the obtained data, stereolithography 3D printing alumina slurry with excellent flowability and low shrinkage was successfully prepared.

BACKGROUND: Slugs mechanically damage plant leaves, resulting in significant economic losses. However, there are limited cost‐efficient strategies available in slug management. By studying how slugs utilize plant volatiles to locate host plants, we can gain insights into the design of attractants and repellents. RESULTS: Bioassay results suggest slugs (Agriolimax agrestis) prefer to orientate to lettuce (Lactuca sativa), cabbage (Brassica oleracea L.), and young tobacco seedlings, compared with old tobacco seedlings. We analyzed the volatomics of lettuce, cabbage, young and old tobacco seedlings. 2‐(2‐butoxyethoxy)‐ethanol acetate (2EA) had high abundance while nonanal, decanal, and β‐cylocitral had relatively low content in volatiles. Old tobacco seedlings released significantly more hexanal but fewer 1,4‐dihydro‐4‐oxopyridazine (DO). In olfactory tests, hexanal, nonanal, decanal, and β‐cylocitral showed strong repellency to slugs, while DO at a dose of 500 ng/μL and 2EA at a dose of 1% were attractive to slugs. The two alkanes, hexadecane and heptadecane, had no effect on slug orientating to host plants. DO and 2EA can thus alleviate the repellency of hexanal, nonanal, decanal and β‐cylocitral. CONCLUSION: The high emission of hexanal in old tobacco seedlings helps repel slugs, while 2EA and DO attract slugs to lettuce and cabbage. These findings suggest that these chemicals can be utilized in the design of repellents and attractants, and contribute to constructing a push–pull system for slug control. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study aimed to explore the impact of different pH values of resuscitation fluid on traumatic hemorrhagic shock (THS), focusing on their effects on glycocalyx and inflammation. A rat model of THS was induced by hemorrhage from a left femur fracture, while an oxygen‐glucose deprivation/reoxygenation (OGD/R)‐induced HULEC‐5a cell model was considered as an in vitro THS model. The lung tissue pathology and glycocalyx structure were assessed through hematoxylin–eosin (H&E) staining and transmission electron microscope examination. The levels of glycocalyx‐related factors and inflammation‐related factors were determined by enzyme‐linked immunosorbent assay (ELISA). The expression of glycocalyx‐related proteins, cell junction‐related proteins, and proteins involved in the PI3K/Akt/NF‐κB signaling pathway was analyzed by western blot. The results showed that both sodium bicarbonate Ringer's solution (BRS) and lactate Ringer's solution (LRS) were effective in restoring mean arterial pressure and heart rate in THS rats. However, LRS has a stronger impact on promoting inflammation and damaging the glycocalyx compared with BRS. In OGD/R‐induced HULEC‐5a cells, a pH of 7.4 and 6.5 increased inflammation and disrupted the glycocalyx, while a pH of 8.1 had no significant effect on inflammation or glycocalyx. Furthermore, the PI3K/Akt/NF‐κB signaling pathway was activated by fluid resuscitation and different pH values. However, the activating effect of BRS and pH 8.1 on the PI3K/Akt/NF‐κB signaling pathway was milder compared with LRS and pH6.5. In conclusion, an alkaline recovery environment was more beneficial for the treatment of THS. [ABSTRACT FROM AUTHOR]

In this article, a 6 mm thick high-strength steel (HSS) was butt laser-MAG welded using nickel alloy wires as the cladding layer. By preparing the cladding layer on the groove, the microstructure and properties of the weld were adjusted. OM, XRD, SEM, and tensile and impact experiments were used to study the structure and mechanical properties of the welded joints. The results show that the weld structure with the cladding layer corresponds to austenite, while the microstructure of the conventional laser arc hybrid welded joint is a combination of austenite and martensite. Additionally, the tensile specimens of the welded joint are fractured at the weld. The fracture strength of the nickel alloy layer is 809 MPa, and the fracture strength of the conventional laser arc hybrid welded joint is 1149 MPa. The low temperature toughness (−40 °C) of conventional laser arc hybrid welded joint is 6.2J. The low temperature toughness (−40 °C) of prefabricated welded joints with laser-filled cladding has increased to 40.8 J, and this proves to be an effective method to improve the low temperature toughness of the welded joint.