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In this work, indium tin oxide(ITO)/tin oxide(SnO2)/titanium dioxide(TiO2)/gold nanoparticles(Au NPs) nanocomposite electrode(ITO/SnO2/TiO2/Au NPs) was prepared and used to develop a photoelectrochemical(PEC) method for the selective detection of sialic acid(SA). Firstly, ITO/SnO2 electrode was prepared by spin coating method, and then TiO2 nanofibers and Au NPs were synthesized on the surface of ITO/SnO2 by electrospinning and magnetron sputtering. Compared with pure SnO2, the photoelectric performance of ITO/SnO2/TiO2/Au NPs nanocomposite electrode is significantly improved. This may be closely related to the local plasmon resonance effect(LSPR) of Au NPs, and the synergistic effect between TiO2/SnO2 heterojunction. After that, 4-mercaptophenylboronic acid (4-MPBA) was modified on the surface of ITO/SnO2/TiO2/Au NPs electrode by Au-S bond, and a PEC sensing platform was developed to specifically detect SA by non-specific esterification reaction between 4-MPBA and SA.

Owing to the vulnerability of Invar to moisture in the membranes of LNG tanker cargo tank construction platforms (CTCPs), an energy-efficient ventilation system is needed to maintain a suitable thermal-moisture environment and a healthy workplace. However, the optimal distribution of supply and return devices that would guarantee worker satisfaction, air quality, and energy efficiency is unclear. Therefore, we conducted numerical simulations to determine the worker satisfaction indices (temperature, relative humidity, and carbon monoxide concentration satisfactions), air quality index (contaminant-removal efficiency), and energy efficiency index (heat-removal efficiency) with supply vane angles ranging from -75° to 0° and two return vent positions (the bottom return vent and the top return vent). The analytic hierarchy process (AHP) entropy weight method was employed to determine the optimal supply vane angle and return vent position for three design targets by considering these indices simultaneously. The results indicated that, with a supply angle of -45° and a bottom return vent, worker satisfaction and air quality were prioritized. Furthermore, a high energy performance of the ventilation system was achieved with a -15° supply angle and a bottom return vent. Moreover, a comprehensive graph of supply vane angles at both return heights, which could provide a reference for optimizing the ventilation system in LNG-CTCPs, is described.

Gold nanoparticles(Au NPs)-sensitized tin dioxide (SnO2) semiconductor not only broadens the visible light absorption range of the material, but also easily forms a Schottky barrier at the heterogeneous interface, which effectively promotes the separation of photogenerated e-/h+ and improves the sensitivity of the sensor. This work explored the one-step synthesis method to prepare SnO2@Au NPs heterogeneous materials, which have high photoelectric conversion efficiency and show better photoelectric properties. Based on the uniformity and firmness of this nanocomposite, the recognition layer can be modified on its surface to construct a "sandwich" biosensor with a sandwich structure to realize the specific photoelectric determination of calprotectin(CP). The linear range is 0.01-20.00 μg·mL-1, the detection limit is as low as 3.2 ng·mL-1, and the specificity is good and stable. In addition, the sensor has also been successfully used to detect CP in actual blood samples and obtained a good recovery rate, which could realize rapid and non-invasive detection of CP.

The Class A1 flame retardant eco-material with excellent comprehensive properties is strongly needed to replace the low-level flame retardant products for potential applications in the building industry. In this work, modified titanium sol with the re-dispersible latex powder (VAE) is compounded to prepare non-combustible flame retardant composites. The optimal content of polylactic acid (PLA) is determined as 10 wt%. The results reveal that the addition of modified titanium sol has simultaneous improvements in flame resistance, water resistance, and mechanical properties of the composite material. The composites with 8 wt% modified titanium sol show low gross heat of combustion (0.646 MJ·kg−1) and low water absorption (4.26%), satisfying the enterprise standards. Besides, the flexural strength of the composites exhibited the maximum at 18.8 MPa. Structure observation discloses that the modified titanium sol promotes the formation of a three-dimensional network structure in the material and further forms a dense protective layer during combustion to inhibit burning. Overall results suggest that the composites with modified titanium sol as the Class A1 flame retardant composite will shed light on their promising applications in the construction industry.

In this paper, the developed finite element model of the shaft-cylindrical roller bearing–bearing housing system is established considering the temperature effect and clearance change. The displacement, raceway stress, and bearing stiffness characteristics of the inner and outer rings of the bearing are systematically investigated. The proposed finite element model is validated through adjusting mesh size of the bearing and the comparison of the elastic deformation of the bearing with the experiment. The influence of load, clearance, and temperature expansion on the displacement distribution of the inner and outer rings of the bearing, raceway stress, and stiffness characteristics are all discussed. The obtained results indicate that an appropriate selection of thermal expansion stress can obtain desirable working ambient temperature of the bearing under different clearances, which can serve as an efficient tool in the design of bearing parameters.

To determine the valve opening for controlling air volume, the relationship among valve opening, static pressure and air volume is studied through experiment. A prediction model for valve opening based on back propagation neural network is proposed. Firstly, the appropriate number of hidden layers and neurons is determined by calculating the error of test set and training set. Secondly, the prediction effect of the model is tested under different conditions. The test result shows that the error between the predicted result and the expected result is less than 5%. Thirdly, the prediction results of the neural network model and the quadratic function model have high consistency. In contrast, neural networks have stronger nonlinear fitting capabilities and are more suitable for solving complex problems. Additionally, compared with the traditional feedback adjustment method, the approximation ability of the neural network model can be used to directly output the position of the VAV terminal demand valve, thus reducing the convergence time and stabilization time, and improving the energy-saving effect and indoor environment comfort. The proposed model can provide reference for the design and debugging of related air supply terminal products, not limited to ship VAV terminal.

This paper is concerned with the design of a multiple-model based fault diagnosis scheme for suspension system of rail vehicles in order to accomplish the task of detecting and isolating faults with reference to multiple actuators. Considering the disturbance caused by rail track unevenness, the multiple actuator-faulty dynamic models together with corresponding observers are set by means of the proposed design procedure. Simulation results illustrate the effectiveness of fault alarm signals as well as the robustness of disturbance and modeling uncertainty of the railway suspension system.

Reclamation changes the characteristics of water movement, then affects the marine environment system, and may even lead to environmental disasters. The influence on the 4 aspects of the current field, wave field, suspended sediment field and topography were summarized. Impacts of large area of reclamation project on the marine environment are found very few, and to expand the study scope and make up for the current lack of a wide range of studies on multiple reclamation impacts on the marine environment is an important research direction in the future; In the long time scale, it is a lack of long-term cumulative effects on coastal reclamation and whether the influence can restore; the present study focuses only on the impact evaluation of scope, type, and degree from lack of exploring the potential mechanism; It is a lack of interdisciplinary research, and the analysis of comprehensive influence of reclamation projects on land, sea and biological and ecological environment.