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To investigate the variations in the flow field of centrifugal pumps with different cavitation numbers, this study utilized the shear stress transport k–ω turbulence model and Zwart–Gerber–Belamri cavitation model to examine the correlation between stall vortices and cavitation flow. The findings indicate that cavitation consistently coincides with the formation of stall vortices, and the distribution of cavitation mirrors the pattern of stall vortex structure. Cavitation tends to develop and aggregate around stall vortices, obstructing a significant portion of inlet areas within the flow channel. As the cavitation number decreases, both the area and intensity of stall vortices increase. For cavitations margins σ = 0.41, 0.23, and 0.15, we observed propagation frequencies of stall vortices at fs = 2.7, 1.8, and 0.9 Hz respectively, as these frequencies decrease relative to impeller movement until reaching near-stationary states. The pressure pulsations in various flow channels exhibit distinct phase differences; smaller cavity numbers result in larger phase disparities along with a gradual reduction in pressure pulsation amplitude. These discoveries present effective strategies for controlling and reducing both cavity formation and pressure fluctuations within centrifugal pumps, thereby enhancing overall stability.

Summary: The USP7 deubiquitinase regulates proteins involved in the cell cycle, DNA repair, and epigenetics and has been implicated in cancer progression. USP7 inhibition has been pursued for the development of anti-cancer therapies. Here, we describe the discovery of potent and specific USP7 inhibitors exemplified by FX1-5303. FX1-5303 was used as a chemical probe to study the USP7-mediated regulation of p53 signaling in cells. It demonstrates mechanistic differences compared to MDM2 antagonists, a related class of anti-tumor agents that act along the same pathway. FX1-5303 synergizes with the clinically approved BCL2 inhibitor venetoclax in acute myeloid leukemia (AML) cell lines and ex vivo patient samples and leads to strong tumor growth inhibition in in vivo mouse xenograft models of multiple myeloma and AML. This work introduces new USP7 inhibitors, differentiates their mechanism of action from MDM2 inhibition, and identifies specific opportunities for their use in the treatment of AML.

Based on fuzzy semi-tensor product (STP) algorithms and fuzzy relation matrix (FRM) models, the design of an adaptive fuzzy controller was proposed in this paper for the multivariable nonlinear systems with uncertainty. The controlled multi-input-and-multi-output (MIMO) plants were expressed and processed first by FRM models and fuzzy STP operations, and then the indirect adaptive fuzzy control laws were designed. The tracking property of the FRM models was proved for the control objective of MIMO systems. The effectiveness of the novel matrix expression was verified by simulations of the tracking control on a two-link rigid robot manipulator. Results in simulation tests show that the proposed design of adaptive FRM control is efficient for nonlinear multivariables. Therefore, the proposed indirect fuzzy adaptive controllers can be extended to general matrix expression for MIMO nonlinear systems with fuzzy STP algorithms and FRM models and online approximate unknown parameters, according to required accuracy.

To enhance the stability of photovoltaic power grid integration and improve power prediction accuracy, a photovoltaic power prediction method based on an improved snow ablation optimization algorithm (Good Point and Vibration Snow Ablation Optimizer, GVSAO) and Bi-directional Long Short-Term Memory (Bi-LSTM) network is proposed. Weather data is divided into three typical categories using K-means clustering, and data normalization is performed using the minmax method. The key structural parameters of Bi-LSTM, such as the feature dimension at each time step and the number of hidden units in each LSTM layer, are optimized based on the Good Point and Vibration strategy. A prediction model is constructed based on GVSAO-Bi-LSTM, and typical test functions are selected to analyze and evaluate the improved model. The research results show that the average absolute percentage error of the GVSAO-Bi-LSTM prediction model under sunny, cloudy, and rainy weather conditions are 4.75%, 5.41%, and 14.37%, respectively. Compared with other methods, the prediction results of this model are more accurate, verifying its effectiveness.

The fundamentals of the design and operation of self-priming pumps, as indispensable equipment in industry, have been the focus of research in the field of fluid mechanics. This paper begins with a comprehensive background on self-priming pumps and gas-liquid two-phase flow, and it outlines recent advances in the field. Self-priming pumps within the gas-liquid two-phase flow state and the spatial and temporal evolution of the transient characteristics of self-priming pumps determine the self-priming pump self-absorption performance. Through mastery of the self-absorption mechanism, high-performance self-absorption pump products can be formed to provide theoretical support for the development of products. In current research, numerical simulation has become an important tool for analyzing and predicting the behavior of gas-liquid two-phase flow in self-priming pumps. This paper reviews existing numerical models of gas-liquid two-phase flow and categorizes them. Reviewing these models not only provides us with a comprehensive understanding of the existing research but also offers possible directions for future research. The complexity of gas–liquid interactions and their impact on pump performance is analyzed. Through these detailed discussions, we are able to identify the challenges in the simulation process and summarize what has been achieved. In order to further improve the accuracy and reliability of simulations, this paper introduces the latest simulation techniques and research methodologies, which provide new perspectives for a deeper understanding of gas-liquid two-phase flow. In addition, this paper investigates a variety of factors which affect the operating efficiency of self-priming pumps, including the design parameters, fluid properties, and operating conditions. Comprehensive consideration of these factors is crucial for optimizing pump performance. Finally, this paper summarizes the current research results and identifies the main findings and deficiencies. Based on this, the need to improve the accuracy of numerical simulations and to study the design parameters in depth to improve pump performance is emphasized.

Silt removal is crucial for maintaining navigable waterways in harbors. Jet pumps, without moving parts, are highly suitable for underwater operations such as channel dredging in port environments. Despite their structural advantages in slurry handling, the prolonged transport of solid–liquid two-phase flows can lead to wear on the wall materials, resulting in decreased efficiency and potential pump failure. The wear characteristics of the jet pump walls due to sand particles of varying grain sizes were experimentally investigated. The characteristic of the sands having a higher distribution above the axis as they enter the jet pump was captured by a high-speed camera. The experiment recorded the variations in mass loss at different sections of the jet pump over a period of 120 h, identifying that backflow within the throat region is a significant contributor to wall wear. Scanning electron microscopy was employed to examine the microstructure of the abraded pump surfaces. It was found that there are noticeable differences in the surface wear microstructure across various pump areas, and that particles of different grain sizes result in distinct wear patterns on the pump surfaces. The underlying causes of this phenomenon were discussed from the perspective of particle motion.

In order to study the effect of tip clearance on the internal cavitation stability of a shunt blade inducer, an external characteristics experiment of a centrifugal pump with a shunt blade inducer was carried out. Based on the turbulence model and mixture model, the cavitating flow in a centrifugal pump with the inducer was numerically simulated. The influence of tip clearance on the cavitating flow in a shunt inducer was studied and analyzed. Through the research, it was found that tip clearance has a certain influence on the critical cavitation coefficient. The existence of the tip clearance caused a significant leakage vortex near the inducer’s inlet and a strong transient effect was shown. The location and degree of cavitation caused by the tip leakage are clarified in this paper. Tip clearance has a great impact on the pressure distribution on a shunt blade inducer. The influence law of tip clearance on an inducer’s blade load distribution was clarified. The results showed that tip clearance has a significant effect on the cavitation of a shunt blade inducer under low flow rate conditions.

The self-priming pump is a kind of centrifugal pump product with self-priming function, and the structural parameters of its reflux hole determine the performance. In order to reveal the mechanism of the self-priming process, we summarized the influence of structure parameters of the reflux hole on the performance of the self-priming pump. In this study, the transparent experimental pump was designed and manufactured, and a visual test bench was built. The gas–liquid two-phase flow pattern during the self-priming process with different reflux hole structure parameters was captured by high-speed camera. Results showed that: (1) the reflux hole of the self-priming pump affected the self-priming performance of the pump by affecting the backflow rate of the gas and liquid phases during the self-priming process. (2) Due to the uneven distribution of liquid velocity in the pump, the position of reflux hole had an obvious impact on the duration of self-priming middle stage, and the shortest duration was 13 s when φ = +15° and the longest duration was 45 s when φ = −30°. (3) The diameter of reflux hole had a very significant impact on the duration of the self-priming middle stage, and the shortest duration was 17 s when d = 10 mm and the longest duration was 94 s when d = 0 mm.

Self-priming pumps are widely used for irrigation, water treatments, and industrial areas due to the self-priming capacity. As we know, the gas-liquid flow pattern during the self-priming process is very complex and still not fully understood. In this study, a visualization test was performed to reveal gas-liquid two-phase flow patterns in a transparent pump during the self-priming process by using high-speed photography. The dynamic change of water column in the inlet-pipe and outlet-pipe was recorded by a digital camera, and the internal flow states of the test pump were recorded by a high-speed camera under different positions and different frame rates. First, the transient gas-liquid flow patterns during the self-priming process were revealed. In the initial stage, a large amount of gas was sucked into the impeller and the water level rose fast in the inlet pipe and then kept steady. With the increase in volume of gas in the impeller, plenty of bubbles were generated rapidly because of the mixing of gas and liquid inside the impeller. Some small bubbles were transported to the gas-liquid separation chamber by the centrifugal force, while rest of bubbles still circulated together with the impeller. In addition, the light gas was discharged to the outlet pipe and the heavy water was reserved inside the chamber due to the effect of gravity force. Afterwards, part of the water and gas flowed back to the impeller through the reflux hole. Second, the dynamic evolution of bubble formation was captured. Many bubbles appeared as the gas pocket was crushed by the blade surface or the jet flow. In general, the self-priming capacity was determined by the mixing rate of gas and liquid, the transporting rate of a gas-liquid mixture from the volute to the gas-liquid separation chamber, and the separating rate of gas from liquid.

High performance data converter is the core device of the fifth generation mobile communication base station system. Its sampling rate is no less than 3 GS/s and the resolution is higher than 12 bit. Therefore, it is inevitable for high-speed serial interface to replace traditional interface circuits. Based on JESD204B protocol, this paper designs a high speed serial interface control layer circuit applied to 3 GS/s 12 bit ADCs. Under the premise of ensuring high-speed transmission, it considers the power consumption and resources in the compromise. The circuit adopts the pre-frequency technique to complete the framing in the transmission layer, and the 8 B/10 B coding is implemented by using the polar information to simplify encoding techniques in the data link layer. In Vivado 16.1 environment, using the Xilinx ZC706 FPGA PHY IP and JESD204B Receiver IP, the verification of the interface circuit proposed in this paper is completed. The experimental results show that the data transmission is correct, the serialized transmission speed is 7.5 Gb/s. Compared with the same type interface design, the transmission speed is increased by 50%.

In order to improve the working performance of the solid–liquid two-phase flow in centrifugal pump, the current study attempted to probe into the influence of the solid-phase particle concentration on the characteristics of centrifugal pump and the drag reduction characteristics of impeller on non-smooth surface. Based on the principle of bionics and with MP80-160 single-stage single-suction centrifugal pump as a model, the current study adopted Eulerian model to carry out numerical simulation by building the pit-type non-smooth surface on the impeller blades. The results show that the higher concentration of solid-phase particles leads to the more centrifugal pump hydraulic head and decreasing efficiency. The pit type in the layout of the non-smooth surface area shows a better drag reduction effect. Shear stress of wall inside the pit is much less than that on the smooth surface, which can effectively improve the working performance of the solid–liquid two-phase flow in centrifugal pump.