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In bridge structure monitoring and evaluation, deformation data serve as a crucial basis for assessing structural conditions. Different from discrete monitoring points, spatially continuous deformation modes provide a comprehensive understanding of deformation and potential information. Terrestrial laser scanning (TLS) is a three-dimensional deformation monitoring technique that has gained wide attention in recent years, demonstrating its potential in capturing structural deformation models. In this study, a TLS-based bridge deformation mode monitoring method is proposed, and a deformation mode calculation method combining sliding windows and surface fitting is developed, which is called the SWSF method for short. On the basis of the general characteristics of bridge structures, a deformation error model is established for the SWSF method, with a detailed quantitative analysis of each error component. The analysis results show that the deformation monitoring error of the SWSF method consists of four parts, which are related to the selection of the fitting function, the density of point clouds, the noise of point clouds, and the registration accuracy of point clouds. The error caused by point cloud noise is the main error component. Under the condition that the noise level of point clouds is determined, the calculation error of the SWSF method can be significantly reduced by increasing the number of points of point clouds in the sliding window. Then, deformation testing experiments were conducted under different measurement distances, proving that the proposed SWSF method can achieve a deformation monitoring accuracy of up to 0.1 mm. Finally, the proposed deformation mode monitoring method based on TLS and SWSF was tested on a railway bridge with a span of 65 m. The test results showed that in comparison with the commonly used total station method, the proposed method does not require any preset reflective markers, thereby improving the deformation monitoring accuracy from millimeter level to submillimeter level and transforming the discrete measurement point data form into spatially continuous deformation modes. Overall, this study introduces a new method for accurate deformation monitoring of bridges, demonstrating the significant potential for its application in health monitoring and damage diagnosis of bridge structures. [ABSTRACT FROM AUTHOR]

Digital Twin (DT) plays a crucial role in intelligent bridge management, and the geometric DT (gDT) serves as its foundation. Notably, the fast and high-precision generation of bridge gDT models has gained increasing attention. This research presents a method for generating high-precision and fast RC bridges with chambers for gDT using terrestrial laser scanning. The method begins with a proposed fast point cloud data collection technique designed specifically for bridges with internal chambers. Subsequently, Euclidean clustering and grid segmentation algorithms are developed to automatically extract contour features from the sliced point clouds. Finally, a framework based on the Dynamo–Revit reverse modelling method is introduced, enabling the automatic generation of gDT models from the identified point cloud features. To validate the feasibility and accuracy of the proposed method, a concrete variable section bridge is used. A comparison is made between the generated gDT model and the point cloud model in terms of 3D deviation, revealing a maximum deviation of 6.6 mm and an average deviation of 3 mm. These results affirm the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Ternary CuO/ZnO/CeO2 catalysts for methanol synthesis from CO2 were successfully prepared and modified by electron etching with plasma as the electron source. Results indicate that the plasma decomposition leads to higher specific surface, unique structure, and the formation of copper species with a high dispersion, while enhancing reducibility of Cu particles and promoting the catalyst‐support interaction due to the especially low temperature of plasma process. Most interesting, electron bombardment produces more oxygen vacancy on CeO2, which facilitates to increase interaction between Cu, Zn, and CeO2. CO2 molecules are preferably adsorbed on the oxygen vacancies of CeO2 to generate carbonate species. Furthermore, the study shows that CeO2 is a highly tunable material, which has great catalytic potential for carbon dioxide due to its unique properties, such as rich oxygen vacancy and metal−support interaction, especially under plasma conditions. Surprisingly, Catalytic evaluation revealed that CuO/ZnO/CeO2 by plasma exhibited a remarkable space‐time yield of 162.7 g methanol·kg–1cat·h–1 (1.5 times of that of conventional calcined catalyst) at 260 °C. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The reaction between magnesium amide and hydride at a molar ratio of 1:2 by means of mechanical ball mining has resulted in the release of a stoichiometric amount of [H.sub.2] and the formation of magnesium nitride. Thermodynamic calculations have shown that the hydrogen release reaction of [1Mg[(N[H.sub.2]).sub.2] + 2Mg[H.sub.2] is mildly endothermic, but the low reaction enthalpy has predicted impractical operation conditions of the hydrogen uptake reaction.

Objective: The aims of this study were to investigate the effects of the vasodilator prostaglandin E1 on microvascular permeability, the expression of vascular endothelial growth factor (VEGF), as well as the structural and functional changes of the peripheral nerve in diabetic rats., Methods: Streptozotocin-induced diabetes mellitus were randomly divided into two groups and intraperitoneally received, once daily, an injection of prostaglandin E1 at 1.6 μg/kg in normal saline or the same volume of normal saline (diabetic control), respectively. Six rats were randomly selected as normal controls., Results: Diabetic controls exhibited a significant increase in the tail flick threshold temperature, water content of the sciatic nerve, serum VEGF level, and VEGF level in the sciatic nerve; in addition, a decrease in the sciatic nerve conduction velocity (NCV) was observed, compared with normal rats (P<0.01). Treatment with prostaglandin E1 resulted in similar changes but at a slower rate than in those without treatment. Diabetic control rats also showed histological and ultrastructural abnormalities of the sciatic nerve, whereas prostaglandin E1-treated rats exhibited similar but less severe injury. The serum VEGF level was negatively correlated with the sciatic NCV (r=-0.932, P<0.01) and positively correlated with the tail flick threshold temperature (r=0.835, P<0.01) as well as the water content of the sciatic nerve (r=0.901, P<0.01)., Conclusion: Prostaglandin E1 could protect the peripheral nerve by improving sciatic nerve function, reducing the VEGF level, and decreasing the vascular permeability. This study provides an experimental proof that prostaglandin E1 has potential benefits in improving DPN in early stage., Competing Interests: The authors have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)