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ABSTRACT As a common method for liquid drainage in wave‐shaped pipelines, foam drainage has been used in gas‐gathering pipelines in various oil and gas fields. One of the common problems encountered in wave‐shaped foam drainage pipelines is the inaccurate prediction of the liquid retention rate. This issue makes it difficult to predict liquid accumulation points, which affects gas output efficiency, causes pipeline corrosion, and generates natural gas hydrates. To clarify the liquid‐holding rate law of wavy foam drainage pipelines is studied. In this study, through experiments to verify the accuracy of the numerical simulation method, we investigate the easiest liquid accumulation points and the liquid‐holding rate of wave‐shaped foam drainage pipelines, with factors such as inlet gas velocity, inlet liquid velocity, import and export differential pressure, undulation angle, and inlet temperature change rule. Among them, the error between the numerical simulation results and the experimental results is 4.68%. Finally, after considering the influence of the aforementioned factors on the liquid retention rate of wave‐shaped pipelines, a new liquid retention rate calculation model for wave‐shaped pipelines with foam drainage is established by introducing dimensionless numbers, such as gas‐phase velocity coefficient, liquid‐phase velocity coefficient, and angle correction coefficient. The method is compared with the results of previous research, and the error is within 15%. The model has a simple form and high calculation accuracy, providing a theoretical basis for pipeline inspectors to predict liquid accumulation conditions and reasonably adjust production schedules.

The light-weight and high-stiffness metal lattice sandwich structure formed by selective laser melting has an important application prospect in aerospace, military and other fields. In this study, the response of square lattice sandwich panels with different core spacings under three-point bending was analyzed by finite element analysis, and the results were verified by experimental samples formed by selective laser melting. The results show that there is a linear relationship between the core spacing and cylindrical bending stiffness when the core spacing is within a certain range, the influence of core spacing on cylindrical bending stiffness is very significant and the influence of core spacing on the cylindrical bending stiffness of the square lattice sandwich panel of 45° is greater than that of the square lattice sandwich panel of 0°. The cylindrical bending stiffness of square lattice sandwich panel of 0° and 45° is basically the same under the same relative density when the relative density is within a certain range, which means that they have similar cylindrical bending stiffness under the same weight. When the relative density is less than 5%, the relative density has a significant influence on the cylindrical bending stiffness, and the influence decreases when the relative density exceeds 5%. With the increase of the core spacing, the stress concentration area is transferred from the part of panel under the loading pad to the ends of cores between the support pads due to the reduction of the cylindrical bending resistance of the lattice structure. According to the mechanical analysis, the initial load prediction formula for the yield and plastic stages can be proposed, The comparison between the theoretical results and the FEA results shows that the relative error is less than 13.6%, indicating that the formula is relatively accurate. The experimental results are in good agreement with the FEA results, especially for the cylindrical bending stiffness, the relative error between the FEA value and the experimental value is only less than 6.5%, indicating that the three-point bending deformation and mechanical properties of the lattice sandwich panel can be effectively predicted by FEA.

Pig welfare is closely related to the economical production of pig farms. With regard to pig welfare assessment, pig sounds are significant indicators, which can reflect the quality of the barn environment, the physical condition and the health of pigs. Therefore, pig sound analysis is of high priority and necessary. In this review, the relationship between pig sound and welfare was analyzed. Three kinds of pig sounds are closely related to pig welfare, including coughs, screams, and grunts. Subsequently, both wearable and non-contact sensors were briefly described in two aspects of advantages and disadvantages. Based on the advantages and feasibility of microphone sensors in contactless way, the existing techniques for processing pig sounds were elaborated and evaluated for further in-depth research from three aspects: sound recording and labeling, feature extraction, and sound classification. Finally, the challenges and opportunities of pig sound research were discussed for the ultimate purpose of precision livestock farming (PLF) in four ways: concerning sound monitoring technologies, individual pig welfare monitoring, commercial applications and pig farmers. In summary, it was found that most of the current researches on pig sound recognition tasks focused on the selection of classifiers and algorithm improvement, while fewer research was conducted on sound labeling and feature extraction. Meanwhile, pig sound recognition faces some challenging problems, involving the difficulty in obtaining the audio data from different pig growth stages and verifying the developed algorithms in a variety of pig farms. Overall, it is suggested that technologies involved in the automatic identification process should be explored in depth. In the future, strengthen cooperation among cross-disciplinary experts to promote the development and application of PLF is also nessary.

Alzheimer’s disease (AD) is an ultimately fatal, degenerative brain disease in the elderly people. In the current work, we assessed the defensive capability of isovitexin (IVX) through an intracerebroventricular injection of streptozotocin (STZ)-induced AD mouse model.

Label-free optical biosensors have become powerful tools in the study of biomolecular interactions without the need for labels. High throughput and low detection limit are desirable for rapid and accurate biomolecule detection. The oblique-incidence reflectivity difference (OI-RD) technique is capable of detecting thousands of biomolecular interactions in a high-throughput mode, specifically for biomolecules larger than 1000 Da. In order to enhance the detection capability of OI-RD for small molecules (typically

Abstract A series of nano-granular films composed of magnetic metal (Fe65Co35) granules with a few nanometers in size and semiconductor oxide (ZnO) have been fabricated by a magnetron sputtering method, and excellent soft magnetic properties have been achieved in a wide metal volume fraction (x) range for as-deposited samples due to the exchange coupling between FeCo granules (a ferromagnetic interaction in nano-scale). In a wide range (0.53 < x < 0.71), the films exhibit coercivity H C not exceeding 15 Oe, along with high resistivity. Especially for the sample with x = 0.67, coercivities in hard and easy axes are 1.43 and 7.08 Oe, respectively, 4πM S = 9.85 kg, and ρ reaches 2.06 × 103 μΩ cm. The dependence of complex permeability μ = μ′ − jμ″ on frequency shows that the real part μ′ is more than 100 below 1.83 GHz and that the ferromagnetic resonance frequency reaches 2.31 GHz, implying the promising for high frequency application. The measured negative temperature coefficient of resistivity reveals that may be the weak localized electrons existing in samples mediate the exchange coupling.