Comparative analysis the performance of electrochemical water softening between high frequency electric fields and direct current electric fields based on orthogonal experimental methods

Electrochemical water softening has been widely used in industrial circulating cooling water systems; however, their low deposition efficiency is the main drawback that limits usage in medium to large enterprises. In this work, the effect of different parameters on the hardness removal efficiency and energy consumption of the electrochemical water softening system is experimentally studied, and the performance of water softening applied by high frequency electric fields and direct current electric fields are comparative analyzed. The impact factors of the electrochemical water softening system are as follows: initial feed concentration of solute, magnitude of voltage, inter-electrode distance, area of cathode and frequency of power supply. To improve the analysis efficiency, the L25 (55) orthogonal table is used to investigate the five different factors at five levels. The experimental results are shown that the initial feed concentration of solute is the most significant factor affecting the hardness removal efficiency. The optimal combination for water softening in the group applied by high frequency electric field and direct current electric field are A3B2C1D4E3 and A2B5C3D1 respectively. The energy utilization of the device applied by high frequency electric field is 3.2 times that applied by direct current electric field. The practice shows that direct current electric fields have a better softening effect, and are is more suitable for scaling ion removal. Particle image velocimetry (PIV) was used to observe the flow field induced by the electrolysis and found that the vertical and horizontal velocities of the flow field at low voltage are conducive to the migration of scaled ions to the cathode, and then the electrolytic reaction and deposition reaction synergy effect is the optimal.

Direct current electric field regulates endothelial permeability under physiologically relevant fluid forces in a microfluidic vessel bifurcation model

In vitro model for blood vessel on-chip reporting on the use of direct current electric fields (DC-EFs) to regulate vascular endothelial permeability, which is important for tissue regeneration and wound healing.

Manipulation of single sub-femtolitre droplets via partial coalescence in a direct-current electric field

It is demonstrated how aqueous droplets with volumes down to the sub-femtolitre range can be manipulated, including the withdrawal of minute samples from the droplets. The underlying principle is that of partial coalescence with a liquid reservoir in an applied electric field. Upon partial coalescence, a droplet merges with a reservoir and reappears with a smaller diameter. The droplets studied here perform a reciprocating motion between two reservoirs during which their volume gets reduced. Manipulation of droplets with diameters down to 400 nm is reported. A similarity relation is derived expressing the ratio of droplet diameters before and after partial coalescence as a function of the ratio between electric and interfacial-tension forces. The presented scheme allows the withdrawal of minute samples from small droplets and could prove helpful in various applications where droplets are used as tiny reaction spaces or when the goal is to tailor the size of individual droplets.

Collective migration of human osteoblasts in direct current electric field

Under both physiological (development, regeneration) and pathological conditions (cancer metastasis), cells migrate while sensing environmental cues in the form of physical, chemical or electrical gradients. Although it is known that osteoblasts respond to exogenous electric fields, the underlying mechanism of electrotactic collective movement of human osteoblasts is unclear. Theoretical approaches to study electrotactic cell migration until now mainly used reaction-diffusion models, and did not consider the affect of electric field on single-cell motility, or incorporate spatially dependent cell-to-cell interactions. Here, we present a computational model that takes into account cell interactions and describes cell migration in direct current electric field. We compare this model with in vitro experiments, in which human primary osteoblasts are exposed to direct current electric field of varying field strength. Our results show that cell-cell interactions and fluctuations in the migration direction together leads to anode-directed collective migration of osteoblasts.