Pump Flow Rate Research Articles

Transdermal Detection of MB-102 and Correlation to Meropenem Pharmacokinetics During Continuous Renal Replacement Therapy: In Vivo Results.

Critically ill patients undergoing continuous renal replacement therapy (CRRT) have medical conditions requiring extensive pharmacotherapy. Continuous renal replacement therapy impacts drug disposition. Few data exist regarding drug dosing requirements with contemporary CRRT modalities and effluent rates. The practical limitations of pharmacokinetic studies requiring numerous plasma and effluent samples, and lack of generalizability of observations from specific CRRT prescriptions, highlight gaps in bedside assessment of CRRT drug elimination and individualized dosing needs. We employed a porcine model using transdermal fluorescence detection of the glomerular filtration rate fluorescent tracer agent MB-102, with the aim to assess the relationship between systemic exposure of MB-102 and meropenem during CRRT. Animals underwent bilateral nephrectomies and received intravenous bolus doses of MB-102 and meropenem. Once MB-102 equilibrated in the animal, CRRT was initiated. Continuous renal replacement therapy prescriptions comprised four combinations of blood pump (low versus high) and effluent (low versus high) flow rates. Changes in transdermal detected MB-102 clearance occurred immediately with a change in CRRT rates. Blood side meropenem clearance mirrored transdermal MB-102 clearance (r2: 0.95-0.97, p value all <0.001). We suggest transdermal MB-102 clearance provides real-time personalized assessment of drug elimination and could optimize prescription of drugs for critically ill patients requiring CRRT.

Heat Transfer Optimization of an Electronic Control Unit Immersed in Forced Liquid Coolant

The current paper aims to present a cooling concept for future centralized platforms of ECUs (Electronic Control Units) from the automotive industry that involves grouping multiple electronic devices into a single system and cooling them with forced convection dielectric coolant. The enhancement consists of replacing the inside air of the module with a dielectric coolant that has a higher thermal conductivity than air and employing an additional prototype system that aids in forced liquid cooling. To meet automotive requirements, the experiments were exposed to an ambient temperature of 85 °C. Temperature measurements on these solutions’ hot spots were compared to those on a thermal paste-only reference electronic module. This study used DFSS (Design for Six Sigma) techniques to determine the ideal pump flow rate, fan air flow rate, and liquid volume in the housing, leading to an optimization in heat dissipation. Finding a trustworthy transfer function that could forecast the impact of the crucial design parameters that had been found was the main goal. The electronics cooled by forced convection coolant improved heat dissipation by up to 60% when compared to the reference module. This demonstrates that the DoE (Design of Experiments) method, which is based on a limited number of measurements, can estimate the behavior of the ECU without the need for a more involved theoretical framework.

Pumping Options for Versatile Test Reactor Molten Lead In-Pile Test Cartridge

The Extended Length Test Article–Cartridge Lead is a test assembly for conducting in-pile research in the Versatile Test Reactor to support the advanced molten lead–cooled reactor under development at the Westinghouse Company. This work investigates four pumping options for circulating molten lead at 500°C and develops an integrated thermal-hydraulic model to estimate the demand curves. The four pumping options fit within cartridge riser tubes that are 57.0 and 68.8 mm in diameter. These options are (1) gas lift pumping, (2) the miniature submerged annular linear induction pump, (3) the miniature submerged direct-current electromagnetic pump, and (4) the miniature axial-centrifugal flow mechanical pump. Gas lift pumping is the simplest and is fully passive with no heat dissipation, but it generates the lowest pumping pressure and flow rate. The mechanical pump and direct-current electromagnetic pump generate the highest pumping pressures, flow rates, and average velocities of molten Pb in the test article of three-fuel rodlets in a triangular lattice. The mechanical pump designs provide the highest flow velocities in the test article and the slowest decrease in pumping pressure with increased flow rate at low thermal power dissipation. The optimized electromagnetic pump designs with no moving parts and elevated temperature ALNICO-5 permanent magnets meet or exceed the target flow velocities in the test article but at higher rate of heat dissipation than the mechanical pump designs.

Shape-Controlled synthesis of conjugated microporous polymer nanotubes and their implementation in continuous flow polymerization

Flow reactors have materialized as a reliable and sustainable approach toward polymer production and processing to promote efficient and uniform irradiation pathways. However, the disadvantages of existing homogeneous photocatalysts including noxiousness, restricted photocatalytic activity and stability, and difficult separation and purification, still pose a great challenge to the advancement of this technique. Herein, conjugated microporous polymer nanotubes (hPorBDP NTs) were fabricated through Sonogashira-Hagihara cross-coupling polycondensation with silica nanorods as sacrificial templates, followed by etching of the inner cores. The hPorBDP NTs with a hollow nanostructure and a highly porous texture were demonstrated to facilitate the separation procedure and provide more accessible active sites for photocatalytic reactions. The hPorBDP NTs were employed as heterogeneous catalysts to activate photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization in batch and in continuous flow system. Screening of the initial monomer concentrations and pump flow rates, high monomer conversions (ɑ > 80%) and narrow dispersities (Đ < 1.15) were achieved in continuous flow system for upscaled production of polymers. Separation and reutilization of the catalyst-bound NTs were realized through facile centrifugation, which resulted in negligible leaching and maintenance of catalytic performance over multiple polymerization cycles. As such, the development of photosynthesis system using hPorBDP NTs as heterogeneous photocatalysts should broaden the application scope of these fascinating catalysts while benefiting synthetic upscaling by continuous flow polymerization.

The Use of Disk-Shaped Diaphragm of Vehicles in Double-Circuit Diaphragm Pumps

Introduction. The article concentrates on improving the efficiency of double-circuit diaphragm pumps, which can be successfully used in heat and water supply systems of industrial and agricultural facilities where there is excess head. It is advisable to equip double-circuit diaphragm pumps with disc-shaped diaphragms interconnected by a rod, for example, from motor vehicles, and to drive them from the available head of the hydraulic network. In order to increase the efficiency of their work and further use, it is necessary to predict the hydraulic characteristics according to the geometric parameters of the membranes and the cycle of their operation in dynamics. Aim of the Article. The article aims at obtaining adequate calculated dependencies of pumped liquid flow rate on speed of double-circuit diaphragm pumps. Materials and Methods. There were used the idealization method from differential geometry, physical experiment, and mathematical statistics to solve the tasks for identifying the relationship between the rod motion and the liquid flow rate for a poppet diaphragm with different geometric surfaces in dynamics. There have been obtained the dependences of pumped liquid volume on the movement of the point of attachment by the poppet diaphragm and the volume flow rate on the movement speed of the point of attachment by the poppet diaphragm with specific geometric parameters for the parabolic and chain line. An experimental testing of the dependence of displaced pumped liquid flow rate on the movement of the attachment point to the stem for the diaphragm type 30 was carried out. Results. Based on the obtained dependences of the volume flow rate on the speed of movement of the point of attachment by a poppet diaphragm with specific geometric parameters for a parabolic and chain line, there were constructed the graphs of dependences of the volume flow rate on the frequency of the working cycle. For practical implementation, there are proposed the dependencies for constructing the hydraulic characteristics of a two-circuit membrane (the dependence of the volume flow rate on the frequency of the working cycle) obtained on the basis of a parabolic interpretation. Discussion and Conclusion. The hydraulic characteristics of a two-circuit membrane pump are close to the equation of a straight line and are consistent with experimental dependencies within 4%.

Experimental test analysis of hydram pump flow rate using L9 Taguchi at fish pond aquaculture

Good water quality in fish nursery cultivation greatly influences the harvest quality. Temperature and Ph can be maintained properly with proper air circulation. The main problem is that the best flow rate quality in fish ponds of 0.123m3/second is only achieved through the flow from the dam. In this study, the installation of hydram pumps in fish ponds was carried out with the angle of assessing the inflow and discharge to adjust to variations in the diameter of the inlet and outlet pipes, the height of the inlet pipe, and the height of the tank. The experimental design used L9 orthogonal array Taguchi with four replicas. The result of this study was that the maximum value of the input flow rate was 305.73 cm3/second, and the discharge flow rate was 40.35 cm3/second. The maximum value was in the 8th composition; namely, the variation of the inlet pipe height was 200 in, the outlet pipe height was 350 cm, the inlet pipe diameter was 1 in, and the outlet pipe diameter was ½ in.

Wearable, Sensing-Controlled, Ultrasound-Based Microneedle Smart System for Diabetes Management.

An intelligent closed-loop system that senses glucose and automatically delivers insulin can provide enhanced glycemic control for diabetes management. Here, we report for the first time on the development of a wearable, sensing-controlled, ultrasound-based closed-loop microneedle smart system for diabetes management. Polylactic acid (PLA) hollow microneedles were fabricated by soft lithography that can maintain excellent mechanical strength and stability in biofluids, followed by the deposition of sensing electrodes on the outer layer. An ultrasonic insulin pump was constructed by integrating a lead zirconate titanate piezoelectric (PZT) ring and a biocompatible stainless-steel sheet with hundreds of tapered holes on top of the inner layer of the microneedles. Both the sensor and the pump were powered and controlled by a printed circuit board (PCB). When the sensing device detects interstitial glucose levels above normal, the closed-loop control algorithm triggers the ultrasonic pump to deliver insulin into the interstitial fluid through the microneedle hollow channels of the PLA microneedles. The ultrasound from the pump can cause the vaporization of insulin in the subcutaneous tissue fluid, accelerate the diffusion rate, and improve the efficiency of insulin treatment and utilization. The system has successfully demonstrated effective control of glucose levels in diabetic rats. The glucose sensor showed a high sensitivity of 0.212 μA/mM at 0-28 mM with a detection limit of 14 μM, and the mean absolute relative difference (MARD) was 9.96% with an average error of 1.6 mM. The flow rate of the ultrasonic pump was 120 μL/min, and the glucose-lowering rate was 4 mM/h. This work may open a new paradigm for the development of intelligent systems for diabetes management, as well as a wide range of practical applications in diabetes patients.

Effects of pumping flow rates on the estimation of hydrogeological parameters

Abstract In this paper, we examine the accuracy of estimating the hydrogeological parameters, transmissivity (T) and storativity (S), in a confined aquifer, when there are not enough available data for pumping flow rate values. While the most popular methods, used to estimate aquifer characteristics, assume that the pumping flow rate is constant during pumping, this is practically infeasible. Violation of this assumption results in errors, which are examined in this paper using field drawdown measurements. To find the aquifer characteristics, we use two methods, testing various pumping flow rates. Firstly, we employ the Cooper -Jacob equations to calculate (T) and (S) values. Afterwards, we use these values to create hypothetical drawdowns using Theis equation and finally we estimate the Root Mean Square Error (RMSE) between the actual and the hypothetical drawdowns. Then, we repeat the same process, replacing the Cooper -Jacob equations with Genetic Algorithms and Theis equation to find the aquifer characteristics by minimizing the RMSE between the actual and the hypothetical drawdowns. Although the process is applied only in three datasets, the results indicate that regardless of the method used, the obtained values of aquifer characteristics (T, S) are not considerably affected by inaccurate pumping flow rate estimations.

Adsorption of Atrazine from Synthetic Contaminated Water Using a Packed-Bed Column with a Low-Cost Adsorbent (Moringa oleifera Lam.)

Atrazine (ATZ) is an herbicide used for increased food production due to its weed and pesticide control capacity in different crops. However, ATZ is a chemical compound that is harmful to the environment and human health, and, unfortunately, it has been detected in surface and groundwater. Therefore, the aim of this paper was to perform the adsorption of Atrazine from a synthetically contaminated water sample using a packed-bed column with a low-cost adsorbent prepared from Moringa oleifera Lam. seeds. The synthesized adsorbent presented an increase in the surface specific area (SBET) of 37% in comparison with the in natura material. The effects of the peristaltic pump flow rate (Q), concentration of the ATZ inlet ([ATZ]inlet) solution, and bed height (H) were studied, with the highest percentage of ATZ removed through the adsorption column (50, 0%) obtained with a packed-bed column with H = 13 cm bed height, Q = 1 mL/min, [ATZ]inlet = 2.0 mg/L, pH = 5.0, a breakthrough time of 25 min, and a saturation time of 420 min. The logistic model was used to best fit the experimental data with an R2 &gt; 0.99, and the Bohart–Adams, Thomas, and Yoon–Nelson models were used to explain and analyze the obtained effects in the continuous adsorption of ATZ. Therefore, the Moringa oleifera Lam. seeds provided a low-cost adsorbent for the continuous adsorption of the herbicide Atrazine in a packed-bed column.

Real-Time Dynamic Performance Enhancement for Solar-Powered Pumping Systems Using PI-Based MPPT Techniques

Abstract The integration of solar-powered pumping systems (SPPS) into agriculture and potable and wastewater sectors becomes mandatory to provide water in remote regions. The broad use of SPPS with classical maximum power point tracking controllers (MPPTCs) showed moderated voltage and power response deterioration. Therefore, the necessity for overcoming these performance degradations and pre-testing of MPPTCs is not an option for the proper operation of such systems. This paper presents a new simple, cost-effective real-time hardware-in-the-loop (RT-HIL) framework to enhance the dynamic performance of SPPS. To accomplish this study, a real pumping station was modeled and equipped with MPPTCs through matlab/simulink. Besides, a practical SPPS was implemented to evaluate the effectiveness of the proposed RT-HIL on system performance. The practical SPPS includes designing a DC-DC buck converter circuit equipped with metaheuristic optimization-based real-time MPPTCs. The tuned PI/FOPI-based MPPTCs are adopted in this work to gain the maximum power from the PV generator under measured real environmental conditions. The proposed real-time MPPTCs techniques are perturb and observe, and incremental conductance (IC) with I, PI, and fractional-order PI (FOPI) controllers. The simulation and the experimental results prove the superiority of the developed real-time FOPI-based MPPTCs in enhancing the system performance in terms of the gained power, module output current, pump flowrate, and pump efficiency. The paper’s novelty lies behind the relatively low-cost real-time execution of PI/FOPI-based MPPT techniques on SPPS. This work was simulated using matlab/simulink in conjunction with Arduino-based RT-HIL and the experimental validation was implemented at the National Water Research Center (NWRC) in Egypt.

Effect of valve spacing on peristaltic pumping

Peristaltic fluid pumping due to a periodically propagating contraction wave in a vessel fitted with one-way elastic valves is investigated numerically. It is concluded that the valve spacing within the vessel relative to the contraction wavelength plays a critical role in providing efficient pumping. When the valve spacing does not match the wavelength, the valves open asynchronously and the volume of the vessel segments bounded by two consecutive valves changes periodically, thereby inducing volumetric fluid pumping. The volumetric pumping leads to higher pumping flowrate and efficiency against an adverse pressure gradient. The optimum pumping occurs when the ratio of valve spacing to contraction wavelength is about . This pumping regime is characterized by a longer period during which the valves are open. The results are useful for further understanding the pumping features of lymphatic system and provide insight into the design of biomimetic pumping devices.

A fiber-packed needle-type extraction device with ionic liquid-based molecularly imprinted polymer as coating for extraction of chlorobenzenes in water samples

A needle-type extraction device (NTED) packed with ionic liquid-based molecularly imprinted polymers (MIP) coated copper fiber was produced for extraction of chlorobenzenes (CBs) in the aqueous environment followed by detection with GC-FID. Precipitation polymerization was performed to synthesize CBs imprinted polymers (CBs-MIP) with CBs as a mixed template, and 1-vinyl-3-aminoformylmethyl imidazolium chloride ionic liquid ([VAFMIM]Cl) as a functional monomer. Then CBs-MIP was coated on the braided copper fiber surface by sol–gel technology, which was served as a coated fiber to extract five trace CBs in drinking water, river water and industrial wastewater. The effects of several experimental conditions on extraction, including extraction time and temperature, pump flow rate, stirring speed, desorption time and temperature were studied by the single factor and experimental design method. A Plackett-Burman design (PBD) was used to screen the significant factors and a Box-Behnken design (BBD) was applied to optimize the significant variables to obtain the optimum extraction conditions. The limits of detection (0.0073–0.0130 μg L−1) and enrichment factors (2158–4087) for studied CBs were obtained after optimization. Moreover, the recoveries of CBs spiked in real water samples were 80.01–97.10% with RSD less than 7.70%. The experimental results confirmed that the NTED packed with CBs-MIP coated fiber is a promising device for extracting trace CBs from the water matrix.

Impact of cardiopulmonary bypass on cerebrovascular autoregulation assessed by ultrafast ultrasound imaging.

Newborns with congenital heart disease undergoing cardiac surgery are at risk of neurodevelopmental impairment with limited understanding of the impact of intra-operative cardiopulmonary bypass (CPB), deep hypothermia and selective cerebral perfusion on the brain. We hypothesized that a novel ultrasound technique, ultrafast power Doppler (UPD), can assess variations of cerebral blood volume (CBV) in neonates undergoing cardiac surgery requiring CPB. UPD was performed before, during and after surgery in newborns with hypoplastic left heart syndrome undergoing a Norwood operation. We found that global CBV was not significantly different between patients and controls (P=0.98) and between pre- and post-surgery (P=0.62). UPD was able to monitor changes in CBV throughout surgery, revealing regional differences in CBV during hypothermia during which CBV correlated with CPB flow rate (R2 =0.52, P=0.021). Brain injury on post-operative magnetic resonance imaging was observed in patients with higher maximum variation in CBV. Our findings suggest that UPD can quantify global and regional brain perfusion variation during neonatal cardiac surgery with this first intra-operative application demonstrating an association between CBV and CPB flow rate, suggesting loss of autoregulation. Therefore, the measurement of CBV by UPD could enable optimization of cerebral perfusion during cardiac surgery in neonates. KEY POINTS: The impact of cardiopulmonary bypass (CPB) on the neonatal brain undergoing cardiac surgery is poorly understood. Ultrafast power Doppler (UPD) quantifies cerebral blood volume (CBV), a surrogate of brain perfusion. CBV varies throughout CPB surgery and is associated with variation of the bypass pump flow rate during deep hypothermia. Association between CBV and bypass pump flow rate suggests loss of cerebrovascular autoregulatory processes. Quantitative monitoring of cerebral perfusion by UPD could provide a direct parameter to optimize CPB flow rate.

Modelling and performance evaluation of a direct steam generation solar power system coupled with steam accumulator to meet electricity demands for a hospital under typical climate conditions in Libya

This study aims to build a dynamic model of a direct steam generation (DSG) solar power system coupled with a steam accumulator to meet electricity demands for a hospital under transient environmental conditions in Libya. The main components of the system are DSG parabolic trough collectors, a steam accumulator, a turbine, a condenser and a circulation pump. The system is modelled via using Simulink\\Simscape software blocks with integrated MATLAB functions to run a dynamic simulation. As the simulation tool reflects the transient operation of the components, advanced control strategies were applied to the model. Using the proportional integral controller (PI controller), safe operation of the system is secured by pump flow rate control, safe turbine operation is provided by pressure control and power output is matched with the demand by using a throttle valve control. 1584 m2 solar collector area and 160 m3 total volume of pressurized steam tank are used in the simulation considering the electricity demand of the hospital and solar radiation in the location. The produced work output was controlled to match the demand profile of the hospital, which needs 200 kW in the peak period and 50 kW at the night. The designed system shows a maximum thermal efficiency of 23.5% for the operation condition.

Conceptual thermal design for 40 ft container type 3.8 MW energy storage system by using computational simulation

Since the application of wind guide and flow circulators makes the flow inside the energy storage system complicated and difficult to predict, research to numerically predict the flow and heat transfer characteristics inside the energy storage system is important. In this study, the cooling performance according to the heat pump discharge angle and wind guide angle was numerically investigated. Three cases were considered to evaluate the cooling performance of the wind guide and flow circulator. The angle of the wind guide and the discharge angle of the heat pump are 5° and 45° in Case 1 and 15° and 30° in Case 2, respectively. Case 3 is a structure in which a flow circulator is applied. In this regard, three-dimensional and computational fluid dynamics simulations have been conducted. As a result, the maximum and average temperatures of the battery rack can be reduced by 11.9 % and 11.17 %, respectively. The cooling performance according to the cooling conditions of the energy storage system was analyzed by analyzing the maximum, average, and minimum temperatures of the battery rack according to the change in the flow rate of the heat pump and the flow circulator.

Analysis of hydraulic characteristics of fluid multiplier fish pump based on CFD simulation

The fish pump is an important power component for aquaculture, especially in offshore engineering vessel aquaculture and cage aquaculture. Reducing fish damage, improving survival rate, and increasing fish-lifting efficiency are the key points of fish pump research. In this study, we took a new type of fluid multiplier fish pump as the research object and selected many performance parameters that affect the hydrodynamic performance of the model prototype of the fish pump. The main conclusions are as follows: the fluid multiplier fish pump body produced a flow rate 2.8–3.5 times higher than the water injection port in the jet gap area, and under the influence of the high-flow-rate area, the low-pressure area generated at the fish inlet amplified the flow at the entrance of the fish. As a result, the fluid multiplier fish pump was able to suck and lift fish. With the change in the water jet gap from 2 mm to 4 mm, the head and flow of the bladeless fish pump were improved to a certain extent. We achieved an optimal value for the runner inclination angle during the change of the inclination angle of the pump body surface from −4° to 4°, and it reached the highest value when the inclination angle was 2°. In the process of increasing the water injection opening of the pump body from 50 mm to 65 mm, the head and flow of the bladeless fish pump greatly increased. The flow when the water injection opening was 65 mm was approximately 1.71 times that when the water injection opening was 50 mm. The head when the water injection opening was 65 mm was approximately 1.42 times that when the water injection opening was 50 mm. When the length of the guide vane was between 4 and 6 mm, the increase and decrease in the flow rate of the bladeless fish pump approached the maximum value of merit. The fluid multiplier fish pump designed in this study featured the characteristics of simple and lightweight structure and high fish-lifting flow, which can reduce labour intensity and improve the catching efficiency of aquaculture fish.

Optimal Performance of Photovoltaic-Powered Water Pumping System

Photovoltaic (PV) systems are one of the promising renewable energy sources that have many industrial applications; one of them is water pumping systems. This paper proposes a new application of a PV system for water pumping using a three-phase induction motor while maximizing the daily quantity of water pumped while considering maximizing both the efficiency of the three-phase induction motor and the harvested power from the PV system. This harvesting is performed through maximum power point tracking (MPPT) of the PV system. The proposed technique is applied to a PV-powered 3 phase induction motor water pumping system (PV-IMWPS) at any operating point. Firstly, an analytical approach is offered to find the optimal firing pattern of the inverter (V-F) for the motor through optimal flux control. This flux control is presented for maximizing the pump flow rate while achieving MPPT for the PV system and maximum efficiency of the motor at any irradiance and temperature. The provided analytical optimal flux control is compared to a fixed flux one to ascertain its effectiveness. The obtained feature of the suggested optimal flux control validates a significant improvement in the system performances, including the daily pumped quantity, motor power factor, and system efficiency. Then converting the data from the first analytical step into an intelligent approach using an adaptive neuro-fuzzy inference system (ANFIS). This ANFIS is trained offline with the input (irradiance and temperature) while the output is the inverter pattern to enhance the performance of the proposed pumping system, PV-IMWPS.

An improved cavitation model with thermodynamic effect and multiple cavitation regimes

Mechanical feed pumps in organic Rankine cycle (ORC) power plants can suffer from cavitation to lose their normal feeding performance or even damage. Cavitation models for organic fluids in ORC systems are lacking presently. Hence, a new cavitation model with thermodynamic effect was proposed. Surface tension-controlled, inertia-controlled, intermediate and heat transfer-controlled cavitation regimes, and two key elements: vapour bubble growth rate and vapour bubble number density are included in the model. A known air or non-condensable gas concentration in the liquid was employed to determine cavitation nuclei number density. The model was coded in ANSYS CFX as user defined model and validated with cavitating flows of organic fluid R114 in a venturi, liquid nitrogen and liquid hydrogen on a tapered hydrofoil and warm water around a hydrofoil NACA 0015 in cavitation tunnels based on visualised cavity length. Two model constants, temperature depression, and minimal cavitation number were correlated to bulk liquid temperature, Reynolds number, and Jakob number. The temperature and pressure profiles of liquid nitrogen and hydrogen on hydrofoil surface were examined against the experimental data. The model was applied to simulate unsteady cavitating flows of organic fluid R245fa in a diaphragm pump. It was shown that the temperature depression and minimal cavitation number cannot be correlated to bulk liquid temperature, Reynolds number and Jakob number. Two model constants can be correlated fairly to Reynolds number. The model underestimates the thermodynamic effect by 43% for R114, 18.6% for liquid nitrogen and 32.6% for liquid hydrogen based on temperature depression. The predicted temperature and pressure profiles on hydrofoil surface agree with the experimental data for liquid nitrogen. The model can produce an expected curve of mean pump flow rate against net positive suction head available.

Validation of Liquid Chromatographic Analytical Method for Determination of Aspirin, Caffeine and Paracetamol in some Pharmaceutical Tablets Form in Iraqi market

In this research, an accurate, efficient and reproducible isocratic reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been developed and validated for the determination of aspirin (ASP), caffeine (CAF), and Paracetamol (PCM). A mixture of drugs as standard material and in formulation tablets were separated using an phenomenex C18 column, (L, 15cm, I.D, 0.46cm, and Size of particle, 5μm), with the shimadzu RP – HPLC, model LC–20 - A, Japan. The eluent phase was optimized through the design, experiment. Elution was done by an eluent phase composed of water (H2O), methanol (MOH) and acetonitrile (ACN) mixture have a ratio of (60: 20: 20, V/V), with adjusted pH of 4.0 with acetic acid, have a pumped flow rate of 0.5mL/min. The drugs, separation were performed at 254nm using a UV-VIS - detector for 8 min. The time of elution for the drugs was recorded at (3.980, 4.366, and 6.894 min) for PCM, CAF and ASP respectively. The validation of the method was conducted in a range of concentration (1 - 100μg/mL) for PCM, CAF and ASP. The method was found to be robust, specified and resisting against the small experimental changes in the value of the flow rate, pH, and wavelength. The LOD were found to be 0.01μg/mL, 0.03μg/mL and 0.05μg/mL for PCM, CAF and ASP respectively. The values of LOQ were 0.033μg/mL, 0.099μg/mL and 0.165μg/mL for PCM, CAF and ASP respectively.

Constant flow rate micropumping using closed-loop control of magnetically actuated nanofluid

In this study, a magnetic actuator is controlled to obtain a constant flow rate micropumping by a magnetic nanofluid flow inside a semicircular-shaped microchannel with a constant square cross-section. A closed-loop control strategy is developed to achieve adequate control by utilizing a model based on experimental data. A novel digital image processing–based real-time velocity estimation algorithm is proposed as feedback information in the closed-loop control system. This paper aims to evaluate the success of the proposed real-time velocity estimation algorithm. The results indicate that the proposed algorithm can supply the fluid velocity inside the microchannel with a maximum deviation of less than 4% in the current micropumping system. Three different controllers—that is, proportional (P), proportional–integral (PI), and proportional–integral–derivative (PID)—are also implemented to test the influence of the control logic used in the closed-loop control strategy. Compared with the previous study, the implementation of a closed-loop control strategy in the present work provided a constant flow rate pumping. The findings reveal that the PID controller can maintain a constant flow rate with transient time values around 186, 94, and 60 seconds for reference values of 100, 200, and 300 µm/s, respectively. In addition, the PID controller could supply a constant flow rate within the microchannel 51% longer than the PI controller.