Passive micromixing can efficiently mix laminar flows through molecular and convective diffusion. Microstructures are expected to be efficient, easily integrated into micromixers, and suitable for micromixers over a wide range of Re. This paper presents the enhancement effects of the multiscale lateral microstructures on the flow field characteristics and mixing efficiency through numerical simulations at Re =  0.01–50. Inspired by the regulation of lateral microstructures on the local flow field, cross-scale staggered baffles (CSBs) were established and applied in typical passive micromixers. For low- Re conditions, the paired trapezoidal microstructures (PTMs) of the CSBs improved the mixing effect by increasing the local streamline tortuosity. For high- Re conditions, the PTMs of CSBs increased the number of expanding vortices in the microchannel, which could increase the size of the fluid interfaces, and an optimal mixing index with relatively little pressure drop was achieved. Moreover, the CSBs were applied to the serpentine curved channel, which caused large expanding vortices on the inner side of the curved channel, and then the state of the Dean vortices on the cross section of the curved channel changed. Therefore, compared with the conventional micromixer channel structure, lateral microstructures regulate the local flow field through the enhancement of the streamlines and the secondary flow effects, and lateral microstructures have great potential to improve the mixing efficiency over a wide range of Re.

In this paper, the effect of washing parameters on the quantity of dye discharge from fabric dyed in highly saturated color (FSC) was discussed. Firstly, the FSC was prepared with reactive red 195 to represent the dark clothes. Secondly, the effect of the washing parameters, including washing time, washing temperature, washing water volume, the weight of FSC, and the dosage of detergent, on dye discharge was analyzed through the single factor test. Thirdly, the mathematical relationship between the quantity of dye discharge (DDQ) and the four washing parameters was discussed through the center combination experiment and response surface method. And a quadratic model was built to predict the quantity of dye discharge when the FSC were washed with different washing parameters. The experimental results indicated that the quantity of dye discharge was affected by the four selected washing parameters and the optimal washing parameters to reduce the quantity of dye discharge can be deduced from the quadratic model. The optimized parameters effectively reduced 0.99 mg dye discharge per liter, and the DDQ reduction rate was up to 53.5%.

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Recently, actuators based on smart materials have attracted considerable research interest owing to their safe and adaptive interaction with humans and harsh environments, which facilitates a wide range of novel functionalities that are difficult to achieve using conventional rigid actuators. [1][2][3][4][5][6] Although such actuators are advantageous, owing to the growing demand for favorable actuator properties, there remains substantial scope for improvement in terms of enabling the actuators to achieve high performance in complex environments. [7][8][9][10][11] At present, the bottleneck in the development of intelligent actuators is mainly associated with improving their response characteristics and mechanical properties, which are mainly limited by the physical trade-off between the force and the velocity of the locomotion structure and the control strategy. [12][13][14][15][16] In nature, the skeletal-tendon structure, which has evolved over millions of years, is a crucial component of the locomotor system of animals. [17][18][19][20][21][22] Its design is well-known for its ability to circumvent the forcevelocity trade-off of muscle motors through the mechanism of power amplification. Moreover, it can improve the energy efficiency, that is, energy transformation, response properties, and mechanical performances, by tuning the storage and release of strain energy in the skeletal-tendon structure. [23][24][25] For example, many birds realize their walking, jumping, and zeropower perching actions by controlling the strain energy stored in their legs' skeletal-tendon system. [26] Similarly, cheetahs benefit from the strain energy stored in their elastic and rigid/semirigid components to achieve excellent running and jumping performance owing to the high-power amplification mechanism of the skeleton-tendon structure in their spine. [27][28][29] These examples have inspired the design of high-power actuators that can achieve excellent response and mechanical properties in different working environments.Many previous studies have demonstrated that tendon-based actuation using tension or shape memory alloy (SMA) cables can effectively provide actuators with high-output and large-strain