Transition metal dichalcogenides (TMDs) are promising materials for photocatalytic functions. In class of TMDs, MoS₂ is comprehensively explored as a co-catalyst due to the extraordinary activity for photocatalytic activity of organic dye degradation. But the catalytic activities of MoS₂ are generated through S ions on depiction edges. Also numerous of S ions existed on basal planes are catalytically inactive. The insertion of external metals in MoS₂ organism is extensive way for activation of basal planes surface to enhance concentration of catalytically active sites. For this purpose, nanoparticles of Nickel (Ni) doped MoS₂ are prepared by hydrothermal technique. Structural and morphological analysis are characterized by XRD and SEM, respectively. XRD results showed that Ni is completely doped into MoS₂. SEM showed that pure MoS₂ has sheet like structure and Ni doped MoS₂ has mix disc and flower like structure. Band gap energy was observed in declining range of 2.30–1.76 eV. The photocatalytic activity of pure MoS₂ and Ni doped MoS₂ were evaluated by degrading MB and RhB dyes under UV light irradiation. MB dye degradation of MB was 71% for pure MoS₂. For 1% to 5% Ni doping in MoS₂, MB dye degradated from 85% to 96%. It means that MB dye degradation of MB was enhanced continuously by increasing the concentration of Ni doping. RhB dye degradation of RhB was 62% for pure MoS₂. For 1% to 5% Ni doping in MoS₂, the RhB dye degradated from 77% to 91%.

In this research work, Polydimethylsiloxane (PDMS) has been used for the fabrication of microchannels for biomedical application. Under the internet of things (IoT)-based controlled environment, the authors have simulated and fabricated bio-endurable, biocompatible and bioengineered PDMS-based microchannels for varicose veins implantation exclusively to avoid tissue damaging. Five curved ascending curvilinear micro-channel (5CACMC) and five curved descending curvilinear micro-channels (5CDCMC) are simulated by MATLAB (The Math-Works, Natick, MA, USA) and ANSYS (ANSYS, The University of Lahore, Pakistan) with actual environments and confirmed experimentally. The total length of each channel is 1.6 cm. The diameter of both channels is 400 µm. In the ascending channel, the first to fifth curve cycles have the radii of 2.5 mm, 5 mm, 7.5 mm, 10 mm, and 2.5 mm respectively. In the descending channel, the first and second curve cycles have the radii of 12.5 mm and 10 mm respectively. The third to fifth cycles have the radii of 7.5 mm, 5 mm, and 2.5 mm respectively. For 5CACMC, at Reynolds number of 185, the values of the flow rates, velocities and pressure drops are 19.7 µLs⁻¹, 0.105 mm/s and 1.18 Pa for Fuzzy simulation, 19.3 µLs⁻¹, 0.1543 mm/s and 1.6 Pa for ANSYS simulation and 18.23 µLs⁻¹, 0.1332 mm/s and 1.5 Pa in the experiment. For 5CDCMC, at Reynolds number 143, the values of the flow rates, velocities and pressure drops are 15.4 µLs⁻¹, 0.1032 mm/s and 1.15 Pa for Fuzzy simulation, 15.0 µLs⁻¹, 0.120 mm/s and 1.22 Pa for ANSYS simulation and 14.08 µLs⁻¹, 0.105 mm/s and 1.18 Pa in the experiment. Both channels have three inputs and one output. In order to observe Dean Flow, Dean numbers are also calculated. Therefore, both PDMS channels can be implanted in place of varicose veins to have natural blood flow.

Approximately 26% of adult people, mostly females, are affected by varicose veins in old age. It is a common reason for distress, loss of efficiency, and worsening living conditions. Several traditional treatment techniques (sclerotherapy and foam sclerotherapy of large veins, laser surgeries and radiofrequency ablation, vein ligation and stripping, ambulatory phlebectomy, and endoscopic vein surgery) have failed to handle this disease effectively. Herein, authors have presented an alternative varicose vein implant method—the descending sinusoidal microchannel (DSMC). DSMC was simulated by Fuzzy logic MATLAB (The MathWorks, Natick, MA, USA) and ANSYS (ANSYS 18.2, perpetual license purchased by Ibadat Education Trust, The University of Lahore, Pakistan) with real and actual conditions. After simulations of DSMC, fabrication and testing were performed. The silver DSMC was manufactured by utilizing a micromachining procedure. The length, width, and depth of the silver substrate were 51 mm, 25 mm, and 1.1 mm, respectively. The measurements of the DSMC channel in the silver wafer substrate were 0.9 mm in width and 0.9 mm in depth. The three descending curves of the DSMC were 7 mm, 6 mm, and 5 mm in height. For pressure, actual conditions were carefully taken as 1.0 kPa to 1.5 kPa for varicose veins. For velocity, actual conditions were carefully taken as 0.02 m/s to 0.07 m/s for these veins. These are real and standard values used in simulations and experiments. At Reynolds number 323, the flow rate and velocity were determined as 1001.0 (0.1 nL/s), 11.4 cm/s and 1015.3 (0.1 nL/s), 12.19 cm/s by MATLAB (The MathWorks, Natick, MA, USA) and ANSYS simulations, respectively. The flow rate and velocity were determined to be 995.3 (0.1 nL/s) and 12.2 cm/s, respectively, at the same Reynolds number (323) in the experiment. Moreover, the Dean number was also calculated to observe Dean vortices. All simulated and experimental results were in close agreement. Consequently, DSMC can be implanted in varicose veins as a new treatment to preserve excellent blood flow in human legs from the original place to avoid tissue damage and other problems.

Straight micro channels are getting importance with time due to its wide spread application in biotechnology and especially in the microenvironment. In microchannel systems the critical mechanisms involve the fluid forces, channel length and radius that affect the flow rate of the fluid. This paper covers simulation of flow control in straight microchannels using fuzzy logic control system. The Mamdani's model in MATLAB was used to study the flow rate of fluid for varying channel radius and applied pressure. Fuzzy rules for the simulation were defined according to the Hagen-Poiseuille equation for this control system. This research work provides valuable information to develop and enhance fuzzy logic based control system for straight microchannels fluid control system under different applied pressures and channel width. The percentage error in MATLAB simulated and the calculated value of volume flow rate parameter was 0.47% which shows the precision of the design model.

Bioengineered veins can benefit humans needing bypass surgery, dialysis, and now, in the treatment of varicose veins. The implant of this vein in varicose veins has significant advantages over the conventional treatment methods. Deep vein thrombosis (DVT), vein patch repair, pulmonary embolus, and tissue-damaging problems can be solved with this implant. Here, the authors have proposed biomedical microdevices as an alternative for varicose veins. MATLAB and ANSYS Fluent have been used for simulations of blood flow for bioengineered veins. The silver based microchannel has been fabricated by using a micromachining process. The dimensions of the silver substrates are 51 mm, 25 mm, and 1.1 mm, in length, width, and depth respectively. The dimensions of microchannels grooved in the substrates are 0.9 mm in width and depth. The boundary conditions for pressure and velocity were considered, from 1.0 kPa to 1.50 kPa, and 0.02 m/s to 0.07 m/s, respectively. These are the actual values of pressure and velocity in varicose veins. The flow rate of 5.843 (0.1 nL/s) and velocity of 5.843 cm/s were determined at Reynolds number 164.88 in experimental testing. The graphs and results from simulations and experiments are in close agreement. These microchannels can be inserted into varicose veins as a replacement to maintain the excellent blood flow in human legs.