Strength Analysis and Structure Optimization of the Crankshaft of an Opposed-Power Reciprocating Pump

The opposed-power reciprocating pump has the characteristics of high pressure, large flow, and high efficiency and energy saving. However, due to the special structure of the opposed-power reciprocating pump, existing theoretical methods cannot analyze its dynamic performance. Therefore, this paper proposes a method of analyzing the power end of the opposed-power reciprocating pump. Firstly, according to the working principle and structural characteristics of the traditional plunger pump, the novel and complex structure of the opposed-power reciprocating pump is analyzed by analogy, and the force analysis model of the crankshaft is established. The dynamic analysis model of the Matlab program is used to solve the dynamic load and section stress in the working process, and the variation law of crankshaft load is obtained. The 25 most critical working conditions are selected for analysis, and the most critical station and section of the crankshaft are obtained. With the connection between ANSYS Workbench and Solidworks, the model is imported into ANSYS Workbench, the load on the crank pin is loaded by APDL command flow, and the static analysis of the crankshaft is carried out to obtain the stress and strain of the crankshaft. Finally, the static and fatigue strength of the dangerous section is checked, and it is proven that the strength and stiffness of the crankshaft meet the design requirements. The results show that the dynamic analysis results of the crankshaft under critical working conditions are consistent with the finite element analysis, verifying the rationality of the method and providing a reference for the improvement and optimized design of the crankshaft of the opposed-power reciprocating pump

A H₂S‐evolving alternately‐catalytic enzyme bio‐heterojunction with antibacterial and macrophage‐reprogramming activity for all‐stage infectious wound regeneration

The disorder of the macrophage phenotype and the hostile by‐product of lactate evoked by pathogenic infection in hypoxic deep wound inevitably lead to the stagnant skin regeneration. In this study, hydrogen sulfide (H2S)‐evolving alternately catalytic bio‐heterojunction enzyme (AC‐BioHJzyme) consisting of CuFe2S3 and lactate oxidase (LOD) named as CuFe2S3@LOD is developed. AC‐BioHJzyme exhibits circular enzyme‐mimetic antibacterial (EMA) activity and macrophage re‐rousing capability, which can be activated by near‐infrared‐II (NIR‐II) light. In this system, LOD exhausts lactate derived from bacterial anaerobic respiration and generated hydrogen peroxide (H2O2), which provides an abundant stock for the peroxidase‐mimetic activity to convert the produced H2O2 into germicidal •OH. The GPx‐mimetic activity endows AC‐BioHJzyme with a glutathione consumption property to block the antioxidant systems in bacterial metabolism, while the O2 provided by the CAT‐mimetic activity can generate 1O2 under the NIR‐II irradiation. Synchronously, the H2S gas liberated from CuFe2S3@LOD under the infectious micromilieu allows the reduction of Fe(III)/Cu(II) to Fe(II)/Cu(І), resulting in sustained circular EMA activity. In vitro and in vivo assays indicate that the CuFe2S3@LOD AC‐BioHJzyme significantly facilitates the infectious cutaneous regeneration by killing bacteria, facilitating epithelialization/collagen deposition, promoting angiogenesis, and reprogramming macrophages. This study provides a countermeasure for deep infectious wound healing via circular enzyme‐mimetic antibiosis and macrophage re‐rousing