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1
Khaustov, A. I., G. G. Boyarsky i K. V. Krotov. "Designing of a Micropump System for Circulatory Support". Journal of the Russian Universities. Radioelectronics 25, nr 5 (28.11.2022): 104–12. http://dx.doi.org/10.32603/1993-8985-2022-25-5-104-112.
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Introduction. Support systems currently used in modern cardiac surgery to provide partial or complete, permanent or temporary replacement of cardiac function are frequently characterized by large dimensions, thus requiring major surgical interventions. Low invasiveness can be ensured by reducing the size of the implanted part of such systems, allowing these devices to be inserted through the femoral artery.Aim. Development of a minimally invasive micropump system to support blood circulation.Materials and methods. Based on the analysis of implementation of micropump circulatory support systems (MCSS), the configuration, operational principles and main components of such a system were determined. When designing a micropump, as a unit defining the weight and size parameters of the entire system, numerical and experimental methods were used to optimize its flow path based on the condition of minimizing blood injury and thrombus formation. The lubrication and cooling system was developed by solving the thermodynamic problem of heat removal. The electronic control unit was developed on the basis of accumulated experience in the design and operation of control units for circulatory support systems.Results. A micropump with a diameter of 6.5 mm and a length of 43 mm with the required hydro- and hemodynamic parameters was designed. The device ensures minimal trauma and thrombus formation. The main MCSS parameters, as well as its main components (electric drives, lubrication and cooling systems), were defined. The configuration and operational principles of the electronic control unit (ECU), consisting in a microprocessor-based control system with feedback, were developed. The ECU built-in software manages the rotational speed of the electric drives of the micropump and coolant supply pump in the required range. In addition, the software is used to measure, display and register the MCSS operational parameters, as well as to monitor their operation in the required ranges and to exchange data between the ECU and the PC.Conclusion. All the necessary documentation for the MCSS nodes and components was prepared. These nodes and components ensure the hydro- and hemodynamic parameters required for the use of the developed minimally invasive micropump system. Future work will address the stages of MCSS assembly and debugging.
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Ni, Jun Hui, Bei Zhi Li i Jian Guo Yang. "A MEMS-Based PDMS Micropump Utilizing Electromagnetic Actuation and Planar In-Contact Check Valves". Advanced Materials Research 139-141 (październik 2010): 1574–77. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.1574.
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This paper presents a novel low-cost poly(dimethylsiloxane) (PDMS) micropump with simple planar design featuring use of compliant in-contact check valves for reliable operation and easy system integration. The micropump mainly consists of two PDMS functional layers: one through-opening layer incorporating the planar in-contact check valves, pump chamber and flow channels, and the other thin membrane layer covering the chamber with a miniature permanent magnet on top for actuation. A special clamping molding technique was used to fabricate the through-opening functional layer, with which the flap-stopper based planar check valve was manipulated to contact each other enabling the minimized leakage flow. The micropump was then characterized by investigating the dependence of pumping flow rate on the driving frequency and backpressure. Testing results exhibit that the micropump is able to produce a flow rate at least of 3.0 μL/min, and work reliably against a backpressure of 1900 Pa, demonstrating the feasibility of this micropump for potential use in various lab-on-a-chip systems.
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Jin, Wenzui, Yimin Guan, Qiushi Wang, Peng Huang, Qin Zhou, Kun Wang i Demeng Liu. "A Smart Active Phase-Change Micropump Based on CMOS-MEMS Technology". Sensors 23, nr 11 (30.05.2023): 5207. http://dx.doi.org/10.3390/s23115207.
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The rational integration of many microfluidic chips and micropumps remains challenging. Due to the integration of the control system and sensors in active micropumps, they have unique advantages over passive micropumps when integrated into microfluidic chips. An active phase-change micropump based on complementary metal–oxide–semiconductor–microelectromechanical system (CMOS-MEMS) technology was fabricated and studied theoretically and experimentally. The micropump structure is simple and consists of a microchannel, a series of heater elements along the microchannel, an on-chip control system, and sensors. A simplified model was established to analyze the pumping effect of the traveling phase transition in the microchannel. The relationship between pumping conditions and flow rate was examined. Based on the experimental results, the maximum flow rate of the active phase-change micropump at room temperature is 22 µL/min, and long-term stable operation can be achieved by optimizing heating conditions.
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Wang, Bao Wei, Xiang Cheng Chua i Long Tu Li. "A Piezoelectric Micropump Based on MEMS Fabrication". Key Engineering Materials 368-372 (luty 2008): 215–17. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.215.
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This paper presents a valve-less micropump which is actuated by a piezoelectric ceramic chip. We employ a microelectromechanical system process for the silicon substrate and anodic bonding for assembly of the Pyrex glass and silicon wafer. The reciprocating type micropump contains two nozzle/diffuser elements and a silicon membrane with an embedded piezoelectric ceramic actuator.
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Wieczorek, Marcin, Paweł Kościelniak, Paweł Świt, Justyna Paluch i Joanna Kozak. "Solenoid micropump-based flow system for generalized calibration strategy". Talanta 133 (luty 2015): 21–26. http://dx.doi.org/10.1016/j.talanta.2014.04.053.
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Leu, Tzong-Shyng, i Ruei-Hung Kao. "Design and operation of a bio-inspired micropump based on blood-sucking mechanism of mosquitoes". Modern Physics Letters B 32, nr 12n13 (10.05.2018): 1840027. http://dx.doi.org/10.1142/s0217984918400274.
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The study is to develop a novel bionic micropump, mimicking blood-suck mechanism of mosquitos with a similar efficiency of 36%. The micropump is produced by using micro-electro-mechanical system (MEMS) technology, PDMS (polydimethylsiloxane) to fabricate the microchannel, and an actuator membrane made by Fe-PDMS. It employs an Nd-FeB permanent magnet and PZT to actuate the Fe-PDMS membrane for generating flow rate. A lumped model theory and the Taguchi method are used for numerical simulation of pulsating flow in the micropump. Also focused is to change the size of mosquito mouth for identifying the best waveform for the transient flow processes. Based on computational results of channel size and the Taguchi method, an optimization actuation waveform is identified. The maximum pumping flow rate is 23.5 [Formula: see text]L/min and the efficiency is 86%. The power density of micropump is about 8 times of that produced by mosquito’s suction. In addition to using theoretical design of the channel size, also combine with Taguchi method and asymmetric actuation to find the optimization actuation waveform, the experimental result shows the maximum pumping flowrate is 23.5 [Formula: see text]L/min and efficiency is 86%, moreover, the power density of micropump is 8 times higher than mosquito’s.
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Liu, Yiqun, Qi Yu, Xiaojin Luo, Le Ye, Li Yang i Yue Cui. "A Microtube-Based Wearable Closed-Loop Minisystem for Diabetes Management". Research 2022 (27.10.2022): 1–14. http://dx.doi.org/10.34133/2022/9870637.
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Diabetes is a chronic metabolic disease with a high blood glucose level, leading to both seriously acute and chronic complications. The closed-loop system is an ideal system for diabetes management. However, the large size and high cost of the commercial systems restrict their widespread uses. Here, we present for the first time a microtube-based wearable closed-loop minisystem for diabetes management. The closed-loop minisystem includes a biosensing device, an electroosmotic micropump, and a printed circuit board (PCB) with an algorithm. The microtube-based sensing device coated on the outer surface of the microtube is inserted into subcutaneous tissue for detecting interstitial glucose; the current signal for sensing glucose is processed by the PCB to power the electroosmotic micropump intelligently for the delivery of insulin into the subcutaneous tissue via the microtube channel. The closed-loop minisystem worn on a diabetic SD rat can successfully maintain its blood glucose level within a safe level. It is expected that this new closed-loop paradigm could open up new prospects for clinical diabetes management.
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Chen, He, Xiaodan Miao, Hongguang Lu, Shihai Liu i Zhuoqing Yang. "High-Efficiency 3D-Printed Three-Chamber Electromagnetic Peristaltic Micropump". Micromachines 14, nr 2 (19.01.2023): 257. http://dx.doi.org/10.3390/mi14020257.
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This paper describes the design and characteristics of a three-chamber electromagnetic-driven peristaltic micropump based on 3D-printing technology. The micropump is composed of an NdFeB permanent magnet, a polydimethylsiloxane (PDMS) film, a 3D-printing pump body, bolts, electromagnets and a cantilever valve. Through simulation analysis and experiments using a single chamber and three chambers, valved and valveless, as well as different starting modes, the results were optimized. Finally, it is concluded that the performance of the three-chamber valved model is optimal under synchronous starting conditions. The measurement results show that the maximum output flow and back pressure of the 5 V, 0.3 A drive source are 2407.2 μL/min and 1127 Pa, respectively. The maximum specific flow and back pressure of the micropump system are 534.9 μL/min∙W and 250.4 Pa/W, respectively.
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Shoji, Eiichi. "Fabrication of a diaphragm micropump system utilizing the ionomer-based polymer actuator". Sensors and Actuators B: Chemical 237 (grudzień 2016): 660–65. http://dx.doi.org/10.1016/j.snb.2016.06.153.
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Gallah, Nader, Nizar Habbachi i Kamel Besbes. "Design and modelling of droplet based microfluidic system enabled by electroosmotic micropump". Microsystem Technologies 23, nr 12 (10.04.2017): 5781–87. http://dx.doi.org/10.1007/s00542-017-3414-9.
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Rodrigues, Eunice R. G. O., Rui A. S. Lapa i José L. F. C. Lima. "A Multicommutated Flow System Based on an Opened‐Loop with Micropump Propulsion". Analytical Letters 40, nr 8 (czerwiec 2007): 1632–45. http://dx.doi.org/10.1080/00032710701380517.
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Wang, Ping, Zilin Chen i Hsueh-Chia Chang. "An integrated micropump and electrospray emitter system based on porous silica monoliths". ELECTROPHORESIS 27, nr 20 (październik 2006): 3964–70. http://dx.doi.org/10.1002/elps.200600120.
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Haldkar, Rakesh Kumar, Vijay Kumar Gupta, Tanuja Sheorey i Ivan A. Parinov. "Design, Modeling, and Analysis of Piezoelectric-Actuated Device for Blood Sampling". Applied Sciences 11, nr 18 (11.09.2021): 8449. http://dx.doi.org/10.3390/app11188449.
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In recent years, micro electro-mechanical system (MEMS)-based biomedical devices have been investigated by various researchers for biomedicine, disease diagnosis, and liquid drug delivery. The micropump based devices are of considerable significance for accurate drug delivery and disease diagnosis. In the present study, design aspects of the piezoelectric actuated micropump used for extraction of blood sample are presented. A pentagonal microneedle, which is an integral part of the micropump, was used to extract the blood volume. The blood was then delivered to the biosensor, located in the pump chamber, for diagnosis. The purpose of such low-powered devices is to get sufficient blood volume for the diagnostic purpose at the biosensor located within the pump chamber, with a minimum time of actuation, which will eventually cause less pain. ANSYS® simulations were performed on four quarter piezoelectric bimorph actuator (FQPB) at 2.5 volts. The modal and harmonic analysis were carried out with various load conditions for FQPB. The extended microneedle lengths inside the pump chamber showed improved flow characteristics. Enhanced volume flow rate of 1.256 µL/s was obtained at 22,000 Hz applied frequency at the biosensor location.
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Verma, P., D. Chatterjee i T. Nagarajan. "Design and development of a modular valveless micropump on a printed circuit board for integrated electronic cooling". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, nr 4 (16.01.2009): 953–63. http://dx.doi.org/10.1243/09544062jmes1315.
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With constraints on size, cost, reliability, and performance for liquid-based cooling systems, the design of modular micropumps suitable for an integrated thermal management system still remains a challenge. In this paper, the effectiveness of a low-cost valveless micropump—heat exchanger on a printed circuit board is investigated for electronic cooling. Signal conditioning and control electronics are integrated with the fluidic components on the substrate to form a compact modular unit. Piezoelectric actuation and conical diffusers are utilized to generate pulsating flow through a minichannel heat sink. With ethanol as the working fluid, the tested pump reached a maximum flowrate and a pressure head of 2.4 ml/min and 743 Pa at an input voltage of 6 VDC. Suitability of the system for active real-time temperature control has been demonstrated at two input heater power levels of 1.45 and 2.5 W. A maximum reduction of 57 per cent in the average heat sink surface temperature could be achieved at a maximum power consumption of 150 mW by the micropump.
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Attiguppe, Ajay Prabhakar, Dhiman Chatterjee i Amitava DasGupta. "A Novel Integrated Transdermal Drug Delivery System with Micropump and Microneedle Made from Polymers". Micromachines 14, nr 1 (27.12.2022): 71. http://dx.doi.org/10.3390/mi14010071.
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Transdermal drug delivery (TDD), which enables targeted delivery with microdosing possibilities, has seen much progress in the past few years. This allows medical professionals to create bespoke treatment regimens and improve drug adherence through real-time monitoring. TDD also increases the effectiveness of the drugs in much smaller quantities. The use of polymers in the drug delivery field is on the rise owing to their low cost, scalability and ease of manufacture along with drug and bio-compatibility. In this work, we present the design, development and characterization of a polymer-based TDD platform fabricated using additive manufacturing technologies. The system consists of a polymer based micropump integrated with a drug reservoir fabricated by 3D printing and a polymer hollow microneedle array fabricated using photolithography. To the best of our knowledge, we present the fabrication and characterization of a 3D-printed piezoelectrically actuated non-planar valveless micropump and reservoir integrated with a polymer hollow microneedle array for the first time. The integrated system is capable of delivering water at a maximum flow rate of 1.03 mL/min and shows a maximum backpressure of 1.37 kPa while consuming only 400 mW. The system has the least number of moving parts. It can be easily fabricated using additive manufacturing technologies, and it is found to be suitable for drug delivery applications.
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Voigt, P., G. Schrag i G. Wachutka. "Electrofluidic full-system modelling of a flap valve micropump based on Kirchhoffian network theory". Sensors and Actuators A: Physical 66, nr 1-3 (kwiecień 1998): 9–14. http://dx.doi.org/10.1016/s0924-4247(97)01783-4.
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Nguyen, N. T., S. Schubert, S. Richter i W. Dötzel. "Hybrid-assembled micro dosing system using silicon-based micropump/ valve and mass flow sensor". Sensors and Actuators A: Physical 69, nr 1 (czerwiec 1998): 85–91. http://dx.doi.org/10.1016/s0924-4247(98)00039-9.
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Li, Kai, Xianxin Zhou, Haoyuan Zheng, Biao Liu, Shuo Chen, Weishan Chen i Junkao Liu. "Achieving Full Forward Flow of Valveless Piezoelectric Micropump Used for Micro Analysis System". Actuators 11, nr 8 (4.08.2022): 218. http://dx.doi.org/10.3390/act11080218.
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The valveless piezoelectric micropump has the advantages of simple structure, high precision and low cost, which can realize the directional transport of micro-fluid and wildly be applied in a micro analysis system. However, backflow at the outlet cannot be avoided due to the limitation of its working mechanism. Large reflux rate can increase the volume control accuracy per cycle, but reduces the stability of the micro analysis system. In order to achieve a full forward flow, which reduce the influence of backflow on the system’s stability, the reflux characteristics of the designed valveless piezoelectric micropump were studied. The condition proposed, which should be satisfied for obtaining full forward flow, is that the reflux rate should be less than 50%. The influence of relations between the size of the key structures and pumping characteristics are established, and the references for structural parameter selection to reduce backflow and achieve full forward flow are given. This paper highlights the methods of controlling the pumping performance and achieving full forward flow, based on structural parameter selection analysis and adjusting excitation. The reflux rate can be reduced to 5% when the inlet angle is increased to 9°. The experimental results verify the validity of the obtained results and the proposed methods of control. This work provides important references for applying valveless piezoelectric micropumps in micro analysis and precision-driven systems.
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Hansen, Thomas Steen, Keld West, Ole Hassager i Niels B. Larsen. "An all-polymer micropump based on the conductive polymer poly (3,4-ethylenedioxythiophene) and a polyurethane channel system". Journal of Micromechanics and Microengineering 17, nr 5 (21.03.2007): 860–66. http://dx.doi.org/10.1088/0960-1317/17/5/003.
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GUAN, Y., Z. XU, J. DAI i Z. FANG. "The use of a micropump based on capillary and evaporation effects in a microfluidic flow injection chemiluminescence system". Talanta 68, nr 4 (15.02.2006): 1384–89. http://dx.doi.org/10.1016/j.talanta.2005.08.021.
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Bußmann, Agnes, Henry Leistner, Doris Zhou, Martin Wackerle, Yücel Congar, Martin Richter i Jürgen Hubbuch. "Piezoelectric Silicon Micropump for Drug Delivery Applications". Applied Sciences 11, nr 17 (30.08.2021): 8008. http://dx.doi.org/10.3390/app11178008.
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Subcutaneous injection is crucial for the treatment of many diseases. Especially for regular or continuous injections, automated dosing is beneficial. However, existing devices are large, uncomfortable, visible under clothing, or interfere with physical activity. Thus, the development of small, energy efficient and reliable patch pumps or implantable systems is necessary and research on microelectromechanical system (MEMS) based drug delivery devices has gained increasing interest. However, the requirements of medical applications are challenging and especially the dosing precision and reliability of MEMS pumps are not yet sufficiently evaluated. To enable further miniaturization, we propose a precise 5 × 5 mm2 silicon micropump. Detailed experimental evaluation of ten pumps proves a backpressure capability with air of 12.5 ± 0.8 kPa, which indicates the ability to transport bubbles. The maximal water flow rate is 74 ± 6 µL/min and the pumps’ average blocking pressure is 51 kPa. The evaluation of the dosing precision for bolus deliveries with water and insulin shows a high repeatability of dosed package volumes. The pumps show a mean standard deviation of only 0.02 mg for 0.5 mg packages, and therefore, stay below the generally accepted 5% deviation, even for this extremely small amount. The high precision enables the combination with higher concentrated medication and is the foundation for the development of an extremely miniaturized patch pump.
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Liu, Guojun, Xuhao Yang, Yan Li, Zhigang Yang, Wen Hong i JianFang Liu. "Continuous Flow Controlled Synthesis of Gold Nanoparticles Using Pulsed Mixing Microfluidic System". Advances in Materials Science and Engineering 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/160819.
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To prepare the gold nanoparticles (AuNPs) with uniform sizes, fine morphology, and good monodispersity, a pulsed mixing microfluidic system based on PZT actuation was presented. The system includes PZT micropump and Y type micromixer. By adjusting voltage (entrance flow rate), pulsed frequency, phase, and other parameters, a variety of mixing modes can be achieved, so as to realize the controllable synthesis of nanoparticles in a certain range. By numerical simulation and analysis, the channel section size, entrance angle, and pulse frequency were optimized. Based on the optimized structure and working parameters, the test prototype has been manufactured in lab, and the related synthesis tests of AuNPs were carried out. The test results indicate that AuNPs with uniform morphology and good monodispersity can be synthesized using the system with the section size (0.4 mm × 0.4 mm), the entrance channel angle (60°) under condition of the pulsed frequency (300 Hz), and the entrance flow rate (4 mL/min). The average diameter and its standard deviation of AuNPs synthesized were 21.6 nm, 4.83 nm, respectively. The research work above can be applied to the fields such as the controlled synthesis of noble metal nanoparticles, biomedicine, and microchemical system.
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Hassan, Rubayet, Sevki Cesmeci, Mahmoud Baniasadi, Anthony Palacio i Austin Robbins. "A Magnetorheological Duckbill Valve Micropump for Drug Delivery Applications". Micromachines 13, nr 5 (30.04.2022): 723. http://dx.doi.org/10.3390/mi13050723.
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In this study, we propose a duckbill valve microfluidic pump that relies on an electromagnetic actuation mechanism. An FEA/CFD-based approach was adopted for the design of the device due to the coupled electromagnetic–solid–fluid interactions in the device. The simulation methodology was confirmed with the previously published data in the literature to ensure the accuracy of the simulations. The proposed optimum duckbill valve micropump can pump 2.45 µL of fluid during the first 1 s, including both contraction and expansion phases, almost 16.67% more than the basic model. In addition, the model can pump a maximum volume of 0.26 µL of fluid at the end of the contraction phase (at 0.5 s) when the magnetic flux density is at maximum (0.027 T). The use of a duckbill valve in the model also reduces the backflow by almost 7.5 times more than the model without any valve. The proposed device could potentially be used in a broad range of applications, such as an insulin dosing system for Type 1 diabetic patients, artificial organs to transport blood, organ-on-chip applications, and so on.
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Doms, Marco, i Jörg Müller. "Design, Fabrication, and Characterization of a Micro Vapor-Jet Vacuum Pump". Journal of Fluids Engineering 129, nr 10 (22.05.2007): 1339–45. http://dx.doi.org/10.1115/1.2776968.
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A microelectromechanical system (MEMS) vapor-jet pump for vacuum generation in miniaturized analytical systems, e.g., micro-mass-spectrometers (Wapelhorst, E., Hauschild, J., and Mueller, J., 2005, “A Fully Integrated Micro Mass Spectrometer,” in Fifth Workshop on Harsh-Environment Mass Spectrometry;Hauschild, J., Wapelhorst, E., and Mueller, J., 2005, “A Fully Integrated Plasma Electron Source for Micro Mass Spectrometers,” in Ninth International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS), pp. 476–478), is presented. A high velocity nitrogen or water vapor jet is used for vacuum generation. Starting from atmospheric pressure, a high throughput of more than 23ml∕min and an ultimate pressure of 495mbars were obtained with this new type of micropump. An approach for the full integration of all components of the pump is presented and validated by experimental results. The pump is fabricated from silicon and glass substrates using standard MEMS fabrication techniques including deep reactive ion etching, trichlorosilane molecular vapor deposition, and metal-assisted chemical etching for porous silicon fabrication. Micromachined pressure sensors based on the Pirani principle have been developed and integrated into the pump for monitoring.
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Nishikata, Kotaro, Masataka Nakamura, Yuto Arai i Nobuyuki Futai. "An Integrated Pulsation-Free, Backflow-Free Micropump Using the Analog Waveform-Driven Braille Actuator". Micromachines 13, nr 2 (13.02.2022): 294. http://dx.doi.org/10.3390/mi13020294.
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The widespread adoption of long-term organs-on-a-chip culture necessitates both active perfusions that mimic physiological flow conditions and minimization of the complexity of microfluidic system and fluid handling. In particular, flow in microtissue such as microvascular is free of pulsation and backflow. The refreshable Braille actuator-based integrated microfluidic system can be employed with simple microchannels and setups. However, due to high pulsatile flow and backflow, ordinary Braille-driven micropumps generate non-physiological flow conditions. We have described a simple method for creating steady flow employing Braille actuators driven with a high-voltage analog waveform, called “constant flow waveform”, without incorporating complicated structures into the microchannel or actuator. We determined the constant flow waveform by measuring volume change of microchannel caused by actuated Braille pins using a conventional fluorescent dye and microscope. Using the constant flow waveform, we demonstrated that a Braille-driven pump reduced pulsating flow by 79% and backflow by 63% compared to conventional Braille-driven pump. Furthermore, we demonstrated that a parallel pair of three-stranded pin pumps effectively eliminated backflow by driving two pumps with the constant flow waveform half-cycle shifted to each other. Moreover, by raising the driving frequency, we could increase the average flow rate to ~2× higher than previously reported flow rate of a typical Braille-driven micropump.
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Su, Y., H. Wang i W. Chen. "Microactuator based on electroplated permanent magnets and flexible polydimethyl siloxane diaphragm". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, nr 3 (1.03.2008): 517–24. http://dx.doi.org/10.1243/09544062jmes596.
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The design, fabrication, and testing of a novel bidirectional magnetic microactuator were presented in the paper. The microactuator is composed of an integrated planar coil and a flexible polydimethyl siloxane (PDMS) diaphragm with embedded CoNiMnP-based permanent magnet arrays. There is a 7 × 7 array of magnets in a unit. The PDMS diaphragm is 2 mm × mm × 40 μm and the magnet post is 50 × 50 × 20 μm. Computer simulation was applied to verify the geometrical parameters. Electroplating under external magnetic field is carried out to improve the magnetic properties of the electroplated magnet, including coercivity, remanence and magnetic energy, and so on. The measured maximum coercivity, remanence and maximum magnetic energy were 2623 Oe (208.73 kA/m), 0.2 T (2000 G), and 10.15 kJ/m3 with the magnetic post, respectively. Moreover, and the deflection of the PDMS membrane is proportional to the exciting current. In a case of 0.35 A current, the maximum deflection of the membrane is 45 μm. Adjusting the electroplating mould results in the variation of the electroplated structure, thus the calibration of the microactuator. Due to the biomedical compatibility and simplicity of the fabrication, the flexible membrane-based microactuator is potential to be used as micropump and optical switch, the microelectromechanical system applications.
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Veeresha, R. K., Muralidhara, Rathnamala Rao i Astron Manoj Tauro. "Investigation on the Performance of Valveless Pump for Microdelivery of the Fluid, Fabricated Using Tool-Based Micromachining Setup". Journal of Advanced Manufacturing Systems 16, nr 02 (czerwiec 2017): 145–56. http://dx.doi.org/10.1142/s0219686717500093.
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Micropump is an integrated part of microfluidic system and is a boon to the field of miniaturization, owing to its helping hand in numerous applications mainly in biomedical, electronic cooling, fuel cells, spacecraft, etc. In this paper, an attempt is made to design and fabricate valveless pump, with active and passive valves. The actuation element used is piezowafer, piezowafer was experimentally tested and compared with simulated values from ANSYS for its peak displacement and these displacements were used to find volume pumped by pump. The pumping volumes found by experimentation are in good agreement with the simulated results. Further fabrication of valveless pump is carried out by using tool-based micromachining center which is a novel type of fabrication technique in micromachining. Through experiments, the optimum frequency of the pump was found to be 60[Formula: see text]Hz at an actuating voltage of 150[Formula: see text]V. The maximum head that a pump could pump was found to be 0.051[Formula: see text]m with pressure of 500.13[Formula: see text]Pa. The flow rate of the pump had a decreasing trend with increase in head.
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Andersen, Truls, Bert Scheeren, Wouter Peters i Huilin Chen. "A UAV-based active AirCore system for measurements of greenhouse gases". Atmospheric Measurement Techniques 11, nr 5 (7.05.2018): 2683–99. http://dx.doi.org/10.5194/amt-11-2683-2018.
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Abstract. We developed and field-tested an unmanned aerial vehicle (UAV)-based active AirCore for atmospheric mole fraction measurements of CO2, CH4, and CO. The system applies an alternative way of using the AirCore technique invented by NOAA. As opposed to the conventional concept of passively sampling air using the atmospheric pressure gradient during descent, the active AirCore collects atmospheric air samples using a pump to pull the air through the tube during flight, which opens up the possibility to spatially sample atmospheric air. The active AirCore system used for this study weighs ∼ 1.1 kg. It consists of a ∼ 50 m long stainless-steel tube, a small stainless-steel tube filled with magnesium perchlorate, a KNF micropump, and a 45 µm orifice working together to form a critical flow of dried atmospheric air through the active AirCore. A cavity ring-down spectrometer (CRDS) was used to analyze the air samples on site not more than 7 min after landing for mole fraction measurements of CO2, CH4, and CO. We flew the active AirCore system on a UAV near the atmospheric measurement station at Lutjewad, located in the northwest of the city of Groningen in the Netherlands. Five consecutive flights took place over a 5 h period on the same morning, from sunrise until noon. We validated the measurements of CO2 and CH4 from the active AirCore against those from the Lutjewad station at 60 m. The results show a good agreement between the measurements from the active AirCore and the atmospheric station (N = 146; RCO22: 0.97 and RCH42: 0.94; and mean differences: ΔCO2: 0.18 ppm and ΔCH4: 5.13 ppb). The vertical and horizontal resolution (for CH4) at typical UAV speeds of 1.5 and 2.5 m s−1 were determined to be ±24.7 to 29.3 and ±41.2 to 48.9 m, respectively, depending on the storage time. The collapse of the nocturnal boundary layer and the buildup of the mixed layer were clearly observed with three consecutive vertical profile measurements in the early morning hours. Besides this, we furthermore detected a CH4 hotspot in the coastal wetlands from a horizontal flight north to the dike, which demonstrates the potential of this new active AirCore method to measure at locations where other techniques have no practical access.
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Wang, C. T., T. S. Leu i J. M. Sun. "Unsteady Analysis of Microvalves With No Moving Parts". Journal of Mechanics 23, nr 1 (marzec 2007): 9–14. http://dx.doi.org/10.1017/s1727719100001027.
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AbstractNo-moving-parts valves (NMPV) pumps produce the net volume flow due to the difference of pressure resistances between forward and reverse flow of a microchannel structure. NMPV has been developed by a number of research groups. However, most of NMPV in these studies are designed and based on steady state flow conditions. Little data is available regarding the NMPV in unsteady flow conditions. In this study, the performances of NMPV under both steady and unsteady flow conditions are investigated numerically. The NMPV used in this study is a diffuser-type microchannel with diffuser angle of 20° because of its outstanding production of net volume flow. By a series of numerical simulations, some useful results would be addressed for the performance of NMPV micropumps. First, Reynolds number confirmed by steady analysis should be greater than 10 (Re > 10) for the NMPV pumps to be more effective. Second, an optimal Strouhal number with maximum net volume flow rate is found at St = 0.013 for the unsteady flow condition. In addition, the relation between the driving pressure amplitude and net volume flow rate with a linear behavior found was helpful to the performance of the micropump system. According to these findings, it was easy for users to operate and design of NMPV micropumps.
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Nasibullayev, I. Sh. "Reducing the systematic error of the average fluid flow rate in axisymmetric computer model of piezoelectric micropump". Multiphase Systems. 16, nr 1 (2021): 22–33. http://dx.doi.org/10.21662/mfs2021.1.004.
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Mathematical and computer models of an axisymmetric coupled problem of interaction of a fluid and an elastic body for the solving partial differential equations by the finite element method FreeFem ++ software are proposed. In these models, periodic vibrations of annular piezoelectric actuators placed on an elastic tube of circular cross-section lead to radial deformations of the tube. With a synchronous oscillation of the system of piezoelectric actuators, the average fluid flow rate is zero. An asymmetric oscillation pattern (micropump mode) results in a nonzero average flow rate. Two types of boundary conditions are considered in the region of contact between the piezoelectric drive and the tube — Dirichlet and Neumann. The computer model was tested for unsteady fluid flow induced by a pressure gradient applied along the pipe with a circular cross section. With synchronous oscillation of piezoelectric actuators, a nonzero average fluid flow is a systematic error. This value was compared with the asymmetric oscillation pattern of piezoelectric actuators to determine the contribution of the systematic error to the pump-generated fluid flow rate. Based on the fluid flow velocity profile and the results of profiling the program code, the optimal parameters of the computational meshes for the channel (dense uniform) and tube walls (nonuniform, consistent with the velocity profile and reconstructing at each time step) were determined, which reduce the magnitude of the systematic error. The main way to reduce the error is to increase the density of the computational mesh, which leads to an increase in the required computing resources. An alternative method is proposed for reducing the systematic error due to an additional pressure drop applied to the channel. Depending on the type of boundary conditions and the number of piezoelectric actuators, this method can reduce the systematic error by 1 − 2 orders of magnitude without increasing the simulation time.
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Mohamed, Youssef, i Christopher L. Passaglia. "A portable feedback-controlled pump for monitoring eye outflow facility in conscious rats". PLOS ONE 18, nr 1 (11.01.2023): e0280332. http://dx.doi.org/10.1371/journal.pone.0280332.
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Intraocular pressure (IOP) is heavily influenced by the resistance of trabecular outflow pathways through which most of the aqueous humor produced by the eye continuously drains. The standard method of quantifying outflow resistance and other aspects of ocular fluid dynamics is eye cannulation, which allows for direct measurement and manipulation of IOP and flow in animal models. Since the method is invasive, indirect techniques that are slower and less accurate must be used for chronological studies. A novel technology is introduced that can autonomously measure outflow facility in conscious rats multiple times a day. A smart portable micropump infuses fluid into the eye through a permanently-implanted cannula and dynamically adjusts flow rate using a unique proportional feedback algorithm that sets IOP to a target level, even though IOP fluctuates erratically in awake free-moving animals. Pressure-flow data collected by the system from anesthetized rats were validated against intraocular recordings with commercial pressure and flow sensors. System and sensor estimates of outflow facility were indistinguishable, averaging 23 ± 3 nl·min-1·mmHg-1 across animals (n = 11). Pressure-flow data were then collected round-the-clock for several days from conscious rats, while outflow facility was measured every few hours. A significant diurnal facility rhythm was observed in every animal (n = 4), with mean daytime level of 22 ± 10 nl·min-1·mmHg-1 and mean nighttime level of 15 ± 7 nl·min-1·mmHg-1. The rhythm correlated with diurnal changes in IOP and likely contributed prominently to those changes based on the day-night swing in facility magnitude. Hence, the portable smart pump offers a unique tool for repeated long-term monitoring of outflow facility and other possible parameters of ocular health. It could also be useful in animal glaucoma studies for reversibly inducing acute or chronic ocular hypertension without explicitly damaging trabecular outflow pathways.
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Guo, Gang, Xuanye Wu, Demeng Liu, Lingni Liao, Di Zhang, Yi Zhang, Tianjiao Mao i in. "A Self-Regulated Microfluidic Device with Thermal Bubble Micropumps". Micromachines 13, nr 10 (28.09.2022): 1620. http://dx.doi.org/10.3390/mi13101620.
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Currently, many microchips must rely on an external force (such as syringe pump, electro-hydrodynamic pump, and peristaltic pump, etc.) to control the solution in the microchannels, which probably adds manual operating errors, affects the accuracy of fluid manipulation, and enlarges the noise of signal. In addition, the reasonable integration of micropump and microchip remain the stumbling block for the commercialization of microfluidic technique. To solve those two problems, we designed and fabricated a thermal bubble micropump based on MEMS (micro-electro-mechanical systems) technique. Many parameters (voltage, pulse time, cycle delay time, etc.) affecting the performance of this micropump were explored in this work. The experimental results showed the flow rate of solution with the assistance of a micropump reached more than 15 μL/min in the optimal condition. Finally, a method about measuring total aflatoxin in Chinese herbs was successfully developed based on the integrated platform contained competitive immunoassay and our micropump-based microfluidics. Additionally, the limit of detection in quantifying total aflatoxin (AF) was 0.0615 pg/mL in this platform. The data indicate this combined technique of biochemical assays and micropump based microchip have huge potential in automatically, rapidly, and sensitively measuring other low concentration of biochemical samples with small volume.
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Darintsev, O. V. "Synthesis of new microfluidics models in the research in the “Robotics and Control in Technical Systems” laboratory". Multiphase Systems 17, nr 1-2 (2022): 74–96. http://dx.doi.org/10.21662/mfs2022.1.007.
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Robotics is an interdisciplinary scientific direction, therefore, when solving a number of problems, it becomes necessary to conduct research that is typical for other areas of science. So, when synthesizing new types of equipment in the „Robotics and Control in Technical Systems” laboratory, more accurate characteristics of individual components and assemblies were required, which ultimately led to a whole cycle of work on microfluidics. Of particular interest in the work performed is the development of new microdevices, since this involves the construction of a single complex of new mathematical and computer models that link hydrodynamics, elasticity theory, heat transfer process, parametric optimization and control theory. The first models were obtained that describe the movement of a piston fixed by an elastic spring in a pipe, taking into account the influence of dry viscous types of friction. By the method of factorial computational experiment, analytical dependencies were obtained for the main part of the fuel dosing unit — servo piston. Next, mathematical and computer models were built to analyze the fluid flow through a channel with variable geometry. Based on the simulation results, the design of a new micromechanical device — a piezoelectric micropump consisting of an elastic tube and annular piezoelements located on it, the sequential oscillation of which creates a non-zero average fluid flow, was refined. In the course of the adaptation of the model, an effective design of the device for smoothing fluid flow pulsations was obtained. These devices were developed and calculated for use in the liquid cooling system of capillary microgripper. A parametric analysis of the process of cooling the hot side of the Peltier element of the microgripper was carried out with a change in the following gripper parameters: the size and shape of the radiator, the coolant flow rate and the heat transfer coefficient. The results of the analysis of temperature fluctuations of the radiator under unsteady fluid flow confirmed the expected dependences of the cooling efficiency on the chosen geometry of the radiator and low-frequency fluid flow fluctuations.
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Mamanee, W., A. Tuantranont, N. V. Afzulpurkar, N. Porntheerapat, S. Rahong i A. Wisitsoraat. "PDMS Based Thermopnuematic Peristaltic Micropump for Microfluidic Systems". Journal of Physics: Conference Series 34 (1.04.2006): 564–69. http://dx.doi.org/10.1088/1742-6596/34/1/093.
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Cesmeci, Sevki, Rubayet Hassan i Mahmoud Baniasadi. "A Comparative Evaluation of Magnetorheological Micropump Designs". Micromachines 13, nr 5 (12.05.2022): 764. http://dx.doi.org/10.3390/mi13050764.
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In this study, we assessed the performance characteristics of five different magnetorheological micropump designs, two of which were our proposed designs, while others were from the existing designs in the literature. Comparisons have been performed based on physics-based simulations, and the fully coupled magneto-solid-fluid interaction simulations were carried out in COMSOL Multiphysics software. For a fair and meaningful comparison, both the material and geometric properties were kept the same, and the simulations were run for one complete pumping cycle. The results showed that the proposed flap and duckbill valve models could pump 1.09 µL and 1.16 µL respectively in 1 s, which was more than the rest of the existing micropump models. Moreover, at 0.5 s, when the magnetic flux density was maximum, the flap and duckbill valve models could pump almost twice as fluid as some of the existing valve models did. The results also demonstrated that the flap and duckbill valve models were nearly five times faster than some of existing models. In conclusion, the proposed two micropump models could propel more net fluid volume than the existing micropump designs, experienced low leakage during the contraction and expansion phase, and had faster response times. We believe that the present study provides valuable insights for future micropump designs, which have an extensive range of application areas, ranging from insulin dosing systems for T1D patients to artificial organs to transport blood and from organ-on-chip applications to micro-cooling systems.
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Chen, Xiao-Ming, Yong-Jiang Li, Dan Han, Hui-Chao Zhu, Chun-Dong Xue, Hsiang-Chen Chui, Tun Cao i Kai-Rong Qin. "A Capillary-Evaporation Micropump for Real-Time Sweat Rate Monitoring with an Electrochemical Sensor". Micromachines 10, nr 7 (7.07.2019): 457. http://dx.doi.org/10.3390/mi10070457.
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Sweat collection and real time monitoring of sweat rate play essential roles in physiology monitoring and assessment of an athlete’s performance during exercise. In this paper, we report a micropump for sweat simulant collection based on the capillary–evaporation effect. An electrochemical sensor is integrated into the micropump, which monitors the flow rate in real-time by detecting the current using three electrodes. The evaporation rate from micropore array, equivalent to the sweat rate, was theoretically and numerically investigated. The designed micropump yields the maximum collection rate as high as 0.235 μ L/min. In addition, the collection capability of the micropump was validated experimentally; the flow rate through the microchannel was further detected in real-time with the electrochemical sensor. The experimental maximum collection rate showed good consistency with the theoretical data. Our proposed device shows the potential for sweat collection and real-time monitoring of sweat rate, which is a promising candidate for being a wearable platform for real-time physiology and performance monitoring during exercise.
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Wu, Di, Bing Shi, Bin Li i Wenming Wu. "A Novel Self-Activated Mechanism for Stable Liquid Transportation Capable of Continuous-Flow and Real-time Microfluidic PCRs". Micromachines 10, nr 6 (28.05.2019): 350. http://dx.doi.org/10.3390/mi10060350.
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The self-activated micropump capable of velocity-stable transport for both single-phased plug and double-phased droplet through long flow distance inside 3D microchannel is one dream of microfluidic scientists. While several types of passive micropumps have been developed based on different actuation mechanisms, until today, it is still one bottleneck to realize such a satisfied self-activated micropump for the stable delivery of both single and double-phased liquid inside long microchannel (e.g., several meters), due to the lack of innovative mechanism in previous methods. To solve this problem, in this article, we propose a new self-activated pumping mechanism. Herein, an end-opened gas-impermeable quartz capillary is utilized for passive transport. Mechanism of this micropump is systemically studied by both the mathematical modeling and the experimental verifications. Based on the flow assays, it totally confirmed a different pumping principle in this paper, as compared with our previous works. The R 2 value of the overall flow rates inside the 3D microchannel is confirmed as high as 0.999, which is much more homogeneous than other passive pumping formats. Finally, this novel micropump is applied to continuous-flow real-time PCRs (both plug-type and microdroplet-type), with the amplification efficiency reaching 91.5% of the commercial PCR cycler instrument.
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Fournier, S., i E. Chappel. "Modeling of a Piezoelectric MEMS Micropump Dedicated to Insulin Delivery and Experimental Validation Using Integrated Pressure Sensors: Application to Partial Occlusion Management". Journal of Sensors 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/3719853.
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A numerical model based on equivalent electrical networks has been built to simulate the dynamic behavior of a positive-displacement MEMS micropump dedicated to insulin delivery. This device comprises a reservoir in direct communication with the inlet check valve, a pumping membrane actuated by a piezo actuator, two integrated piezoresistive pressure sensors, an anti-free-flow check valve at the outlet, and finally a fluidic pathway up to the patient cannula. The pressure profiles delivered by the sensors are continuously analyzed during the therapy in order to detect failures like occlusion. The numerical modeling is a reliable way to better understand the behavior of the micropump in case of failure. The experimental pressure profiles measured during the actuation phase have been used to validate the numerical modeling. The effect of partial occlusion on the pressure profiles has been also simulated. Based on this analysis, a new management of partial occlusion for MEMS micropump is finally proposed.
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Liu, Xiaopeng, Xingqi Li, Meng Wang, Shuaiqi Cao, Xinfeng Wang i Guojun Liu. "A High-Performance Piezoelectric Micropump with Multi-Chamber in Series". Applied Sciences 12, nr 9 (28.04.2022): 4483. http://dx.doi.org/10.3390/app12094483.
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Based on the multi-chamber series structure, a piezoelectric micropump with high output performance is proposed in this paper. The proposed micropump is composed of the circular unimorph piezoelectric vibrator, the cantilever check valve, and the pump body. First, the working process of the piezoelectric micropump was analyzed in detail. Then, the effect of the key dimension parameters on the output performance of the micropump was explored. The key dimension parameters mainly refer to the height of the pump chamber and valve opening (the deformation size of the valve). Finally, experimental prototypes with different parameters were fabricated for the evaluation of the output performance of the micropump. The experimental results show that when the pump chamber height is 0.1 mm and the valve opening is 0.4 mm, the piezoelectric micropump has a good comprehensive output performance. In particular, at 170 V and 120 Hz, the maximum flow rate of the dual-chamber series pump is 65.5 mL/min, and at 100 Hz, the maximum output pressure reaches 59.1 kPa. Moreover, at a certain voltage of 170 V, when the drive frequency is 450 Hz and 550 Hz, the output flow rate and pressure of the four-chamber series pump reach a maximum of 110 mL/min and exceed 140 kPa, respectively. In addition, the volumes of the proposed single-chamber, dual-chamber series, and four-chamber series micropumps are 22 mm × 22 mm × 5 mm, 32.6 mm × 22 mm × 5 mm, and 53.8 mm × 22 mm × 5 mm, respectively. The proposed piezoelectric micropump has the advantages of simple structure, low cost, miniaturization, and high output performance, thus gaining potential practicality for biomedical applications, cooling systems, fuel supply, chemical applications, etc.
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Zhou, Xuyan, Meng Gao i Lin Gui. "A Liquid-Metal Based Spiral Magnetohydrodynamic Micropump". Micromachines 8, nr 12 (18.12.2017): 365. http://dx.doi.org/10.3390/mi8120365.
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Nasibullayev, I. Sh, i O. V. Darintsev. "Two-dimensional dynamic model of the interaction of a fluid and a piezoelectric bending actuator in a plane channel". Multiphase Systems 14, nr 4 (2019): 220–32. http://dx.doi.org/10.21662/mfs2019.4.029.
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The paper proposes a two-dimensional computer model of the fluid flow in a plane channel under the action of an applied pressure drop with a flat ceramic piezoelectric actuator immersed in it, bending in the transverse direction in proportion to the applied electric voltage. A mathematical model of the coupled liquid-piezodrive system in variational form for numerical simulation by the finite element method is proposed. Since the assignment of the Dirichlet boundary conditions for displacement in this problem, is difficult, an equivalent piezo actuator deformation scheme using the Neumann boundary conditions is constructed. The deformations and equivalent stresses of von Mises on a piezo actuator are calculated. The influence of the geometry of the channel and the hydrodynamic resistance formed by the piezo actuator on the dynamics of the fluid flow is analyzed. An algorithm is proposed for adaptive dynamic remeshing of the channel computational mesh under deformations exceeding the size of finite elements. With a symmetric control signal supplied to the piezoelectric actuator, the asymmetry of the geometry leads to a violation of the symmetry of the fluid flow within the period, both in terms of fluid flow rate and in time. In the absence of a pressure drop at low frequencies of the oscillations of the piezoelectric element (of the order of the inverse relaxation time of the velocity), the period-average liquid flow rate is nonzero and increases with increasing frequency. In the presence of an external pressure drop along the layer, the average liquid flow rate is proportional to the pressure drop; at low frequencies, it is inversely proportional to the frequency; with increasing frequency, it reaches saturation. Based on the results of numerical modeling, various variants of new microfluidic technical devices generating a fluid flow using a piezoelectric bending actuator are proposed: a micropump creating a closed-circuit flow; fluid flow regulator and fluid volume dispenser.
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Hong, Yiying, Misael Diaz, Ubaldo M. Córdova-Figueroa i Ayusman Sen. "Light-Driven Titanium-Dioxide-Based Reversible Microfireworks and Micromotor/Micropump Systems". Advanced Functional Materials 20, nr 10 (25.05.2010): 1568–76. http://dx.doi.org/10.1002/adfm.201000063.
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Jumril Yunas, Muzalifah Mohd Said, Roer Eka Pawinanto, Badariah Bais, Budi Mulyanti, Ida Hamidah, Asep Bayu Dani Nandiyanto i Burhanuddin Yeop Majlis. "Magnetic Polymer Based Micropumps for Microfluidic Sample Delivery System". Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 85, nr 1 (29.07.2021): 12–21. http://dx.doi.org/10.37934/arfmts.85.1.1221.
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In this paper we present the development of electromagnetic (EM) microfluidic pumps incorporating the magnetic polymer composite for the transport of microfluidic bio-sample. The pump system includes the electromagnetic field generator, a flexible actuator membrane made of polymer material with embedded magnetic particles and valve-less microfluidic channel and chamber. The micropump is fabricated using a MEMS process with additional bonding process. Various types of the magnetic membrane as well as electromagnetic coils were fabricated and characterized to find optimum pump performance. As the results, it is found that the fabricated pump systems were able to deliver fluidic sample within a large flow-rate range from 6 ml/min down to several nl/min which can be adjusted by setting the input electrical current parameters, such as intensity, frequency and type of the current signal.
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Zhang, Rumi, Graham A. Jullien i Colin Dalton. "Study on an alternating current electrothermal micropump for microneedle-based fluid delivery systems". Journal of Applied Physics 114, nr 2 (14.07.2013): 024701. http://dx.doi.org/10.1063/1.4813484.
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Guan. "Performance Analysis of a Microfluidic Pump Based on Combined Actuation of the Piezoelectric Effect and Liquid Crystal Backflow Effect". Micromachines 10, nr 9 (31.08.2019): 584. http://dx.doi.org/10.3390/mi10090584.
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A novel combined actuation method based on the piezoelectric effect and liquid crystal backflow effect is proposed in this paper. The coupling mechanism of a piezoelectric transducer (PZT) and liquid crystal (LC) in a combined driving mode is analyzed, and the governing equations of electromechanical coupling based on inverse piezoelectric effect and the classical Leslie–Ericksen backflow equation are modified under combined driving method. The new multifield coupling dynamic equations for numerical analysis is established. Experimentally, a sandwiched micropump was manufactured and sealed with wet etching technology on a glass wafer. A testing platform was built to analyze the particles motion and the flow rates were measured with both single PZT or LC actuation and combined actuation. Comparing the results of the numerical analysis and experimental testing of the flow rate and LC molecule motion under different driving voltages and frequencies, the performance of the PZT/LC combined driving is found to be superior to that of the single driving mode (PZT or LC driving) under the same driving conditions. Moreover, the new combined driving mode overcome the disadvantages of single driving mode and enhance the driving efficiency significantly. The simulation results are in good agreement with the experimental data. The maximum flow rate of the micropump achieved was 4.494 μL/min with combined driving method.
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Kim, Joon-Wan, Thanh V. X. Nguyen, Kazuya Edamura i Shinichi Yokota. "Triangular Prism and Slit Electrode Pair for ECF Jetting Fabricated by Thick Micromold and Electroforming as Micro Hydraulic Pressure Source for Soft Microrobots". International Journal of Automation Technology 10, nr 4 (5.07.2016): 470–78. http://dx.doi.org/10.20965/ijat.2016.p0470.
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In this paper, we propose a triangular prism and slit electrode pair (TPSE) and its micromechanical systems (MEMS) fabrication process for a novel micropump using electro-conjugate fluid (ECF), which is based on a thick photoresist (KMPR) micromold (≥ 500 μm) and nickel electroforming. ECF is a kind of functional and dielectric fluid. The strong and active jet flow of an ECF is generated between two electrodes surrounded by the ECF when a high direct-current voltage is applied to the electrode pair. The micropumps generated by the ECF jetting can be used as micro hydraulic pressure sources for soft microrobots. By substituting these ECF micropumps for bulky air compressors or hydraulic pumps utilized in soft robots, we can realize advanced soft microrobots in which the driving sources are embedded. An MEMS-based TPSE for an ECF micropump was successfully fabricated by using the proposed MEMS fabrication process. The maximum output pressure without a flow and the flow rate without a load were 24.6 kPa and 27.5 mm3/s, respectively, at an applied voltage of 2 kV. The experimental results show that the MEMS-fabricated TPSE is a good candidate for electrode-type ECF micropumps utilized in various applications of soft microrobots whose pressure sources are embedded inside.
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Uvarov, Ilia V., Pavel S. Shlepakov, Artem E. Melenev, Kechun Ma, Vitaly B. Svetovoy i Gijs J. M. Krijnen. "A Peristaltic Micropump Based on the Fast Electrochemical Actuator: Design, Fabrication, and Preliminary Testing". Actuators 10, nr 3 (18.03.2021): 62. http://dx.doi.org/10.3390/act10030062.
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Microfluidic devices providing an accurate delivery of fluids at required rates are of considerable interest, especially for the biomedical field. The progress is limited by the lack of micropumps, which are compact, have high performance, and are compatible with standard microfabrication. This paper describes a micropump based on a new driving principle. The pump contains three membrane actuators operating peristaltically. The actuators are driven by nanobubbles of hydrogen and oxygen, which are generated in the chamber by a series of short voltage pulses of alternating polarity applied to the electrodes. This process guaranties the response time of the actuators to be much shorter than that of any other electrochemical device. The main part of the pump has a size of about 3 mm, which is an order of magnitude smaller in comparison with conventional micropumps. The pump is fabricated in glass and silicon wafers using standard cleanroom processes. The channels are formed in SU-8 photoresist and the membrane is made of SiNx. The channels are sealed by two processes of bonding between SU-8 and SiNx. Functionality of the channels and membranes is demonstrated. A defect of electrodes related to the lift-off fabrication procedure did not allow a demonstration of the pumping process although a flow rate of 1.5 µL/min and dosage accuracy of 0.25 nL are expected. The working characteristics of the pump make it attractive for the use in portable drug delivery systems, but the fabrication technology must be improved.
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Qi, Chao, Naohiro Sugita i Tadahiko Shinshi. "A Disposable Electromagnetic Bi-Directional Micropump Utilizing a Rotating Multi-Pole Ring Magnetic Coupling". Micromachines 13, nr 10 (21.09.2022): 1565. http://dx.doi.org/10.3390/mi13101565.
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Electromagnetic bi-directional micropumps (EMBM) are indispensable for the development of portable devices which enable fluid transportation in forward and reverse directions. However, the high disposal cost of rare-earth magnets attached to the fluidic part and the low pump density due to multiple motors limit their practical application in disposable multi-channel microfluidic applications such as droplet-based oscillatory-flow (DBOF) rapid PCR amplification. Therefore, this paper presented a low-cost, disposable, high-pump-density EMBM. To reduce the disposal cost, we separated the magnets from the disposable fluidic part and used cylindrical holes to store and guide the magnet, which resulted in the ability to reuse all the magnets. To increase the pump density, we used the combination of one motor and one multi-pole ring magnet to drive several channels simultaneously. A proof-of-concept prototype with a pump density of 0.28 cm−2 was fabricated and experimentally evaluated. The fabricated micropump exhibited a maximum flow rate of 0.86 mL/min and a maximum backpressure of 0.5 kPa at a resonant frequency around 50 Hz. The developed multi-channel micropump with reusable magnets is highly beneficial to the development of low-cost and high-throughput rapid PCR amplification microchips and therefore can have a significant impact on timely infectious disease recognition and intervention.
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Singhal,, Vishal, Suresh V. Garimella, i Arvind Raman. "Microscale pumping technologies for microchannel cooling systems". Applied Mechanics Reviews 57, nr 3 (1.05.2004): 191–221. http://dx.doi.org/10.1115/1.1695401.
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A review of the state of the art in micropumping technologies for driving fluid through microchannels is presented with a particular emphasis on small-scale cooling applications. An extensive variety of micropumping techniques developed over the past fifteen years in the literature is reviewed. The physical principles, engineering limitations, and advantages of approximately twenty different kinds of micropumps are reviewed. The available micropumping techniques are compared quantitatively, primarily in terms of the maximum achievable flow rate per unit cross-sectional area of the microchannel and the maximum achievable back pressure. A concise table is developed to facilitate the convenient comparison of the micropumps based on different criteria including their miniaturization potential, size (in-plane and out-of-plane), actuation voltage and power required per unit flow rate, ease and cost of fabrication, minimum and maximum frequency of operation, and suitability for electronics cooling. Some important performance characteristics of the micropumps, which are likely to be decisive for specific applications, are also discussed. The current state of the art in micropump design and fabrication is also comprehensively reviewed. There are 171 references cited in this review article.
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Shinha, Kenta, Wataru Nihei, Hiroko Nakamura, Tomomi Goto, Takumi Kawanishi, Naoki Ishida, Nao Yamazaki i in. "A Kinetic Pump Integrated Microfluidic Plate (KIM-Plate) with High Usability for Cell Culture-Based Multiorgan Microphysiological Systems". Micromachines 12, nr 9 (24.08.2021): 1007. http://dx.doi.org/10.3390/mi12091007.
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Microphysiological systems (MPSs), including organ-on-a-chip (OoC), have attracted attention as a novel method for estimating the effects and side effects of drugs in drug discovery. To reproduce the dynamic in vivo environment, previous MPSs were connected to pump systems to perfuse culture medium. Therefore, most MPSs are not user-friendly and have poor throughput. We aimed to develop a kinetic pump integrated microfluidic plate (KIM-Plate) by applying the stirrer-based micropump to an open access culture plate to improve the usability of MPSs. The KIM-Plate integrates six multiorgan MPS (MO-MPS) units and meets the ANSI/SBS microplate standards. We evaluated the perfusion function of the kinetic pump and found that the KIM-Plate had sufficient agitation effect. Coculture experiments with PXB cells and hiPS intestinal cells showed that the TEER of hiPS intestinal cells and gene expression levels related to the metabolism of PXB cells were increased. Hence, the KIM-Plate is an innovative tool for the easy coculture of highly conditioned cells that is expected to facilitate cell-based assays in the fields of drug discovery and biology because of its usability and high throughput nature.