3-way Valve Research Articles

Microflow Injection System for Efficient Cu(II) Detection across a Broad Range

In this study, a modular, multi-step, photometric microflow injection analysis (micro-FIA) system for the automatic determination of Cu(II) in a bioreactor was developed. The system incorporates diverse 3D-printed modules, including a platform formed by a mixer module to mix Cu(II) with hydroxylamine, which reduces Cu(II) to Cu(I) linked to a diluter module via a Tesla valve, a chelation mixer module, a disperser module, and a detector module provided by an LED light source at λ = 455 nm and a light dependence resistor (LDR) as a light intensity detector. The system measures the color intensity resulting from the chelation between Cu(I) and neocuproine. The micro-FIA system demonstrated good capability for automatic and continuous Cu(II) determination, in a wide range of Cu concentrations, from 34 to 2000 mg L−1. The device exhibits a good repeatability (coefficient of variation below 2% across the measured concentration range), good reproducibility, and has an accuracy of around 100% between 600 and 1900 mg L−1. Real samples were analyzed using both the micro-FIA system and an atomic absorption spectroscopy method, revealing no statistically significant differences. Additionally, a Tesla valve located before the detector substituted a 3-way solenoid valve, eliminating the need for moving parts.

Effects of 3-way valve faults and capillary tube clogging on the dynamic behavior of compressor power consumption during start-up operation of a household refrigerator-freezer

To expedite the quality inspection (QI) on household refrigerator-freezer (HRF) production lines, rapid and accurate fault detection and diagnosis during the brief start-up operation period are essential. This requires a thorough understanding of the HRF’s dynamic behavior during this phase and the selection of a suitable fault indicator from the measurable parameters. This study investigates the dynamic behavior of compressor power consumption during the HRF’s initial 20-minute start-up operation under specific failure conditions, such as blockage and leakage of the 3-way valve, and capillary tube clogging. These conditions were examined through six distinct failure scenarios. The findings reveal that alterations in the refrigerant path due to these faults are immediately reflected in the compressor power consumption, both quantitatively and qualitatively. The compressor power data, serving as a fault detection indicator, displayed clear changes resulting from modifications in the refrigerant passage due to the faults examined. However, it was not possible to determine the exact location of the refrigerant passage blockage, whether it was the 3-way valve or the capillary tube, based solely on the compressor power data. This highlights the need for an auxiliary fault indicator.

An open-source smart fraction collector for isocratic preparative liquid chromatography

Preparative liquid chromatography is a technique for separating complex samples or isolating pure compounds from complex extracts. It involves eluting samples through a packed column and selectively collecting or isolating the separated bands in a sequence of fractions. Depending on the column length and the sample complexity, a large number of fractions may be obtained, making fraction collection a laborious and time-consuming process. Manual fraction collection is also tedious, error-prone, less reproducible, and susceptible to contamination. Several commercial and lab-made solutions are available for automated fraction collection, but most systems do not synchronize with the instrument detector and collect fractions at fixed volumes or time intervals. We have assembled a low-cost Arduino-based smart fraction collector that can record the signal from the UV–vis detector of the chromatography instrument and enable the automated selective collection of the targeted bands. The system consists of a robot equipped with position sensors and a 3-way solenoid valve that switches the column effluent between the waste or collection positions. By proper programming, an Arduino board records the detector response and actuates the solenoid valve, the position sensors, and the stepper motors to collect the target chromatographic bands.

Function of the Speech Recognition of the Smartphone to Automatically Operate a Portable Sample Pretreatment Microfluidic System.

We proposed a portable sample pretreatment microsystem, which can be automatically operated through speech recognition in a smartphone app. The proposed sample pretreatment microsystem consists of a microfluidic chip, an air router, pressure and vacuum lines with air pump motors, six 3-way solenoid valves, and a microcontroller with a Bluetooth module. The command of a human voice conducted the whole process of DNA extraction from pathogenic bacterial samples. Thus, manual interference during the DNA extraction is eliminated, preventing any potential infection from human touch. The palm-sized sample pretreatment microsystem can be run by a portable battery or a conventional smartphone charger. Genomic DNA ofSalmonella typhimuriumwas purified on a chip in less than 1 min with an extraction efficiency of 70 ± 5%.

A Study on the Control Solution of Ship’s Central Fresh Water-Cooling System for Efficient Energy Control Based on Merchant Training Ship

Large ships adopt a central fresh water-cooling system that indirectly cools waste heat with seawater to discharge the ship′s waste heat out of the ship. Such a central fresh water-cooling system is essential for future electric powered ships. Since 2010, shipping companies have attempted to save energy by applying variable-speed cooling pumps to the central FW cooling system, but due to the minimum-required discharge pressure of the pump, they have applied the existing 3-way valve system alongside. However, since the control systems of the variable-speed cooling pump and the 3-way valve are controlled by the same output variable, the two control systems collide during operation. Therefore, for efficient energy-saving control, it is important to accurately model the central fresh water-cooling system and find the optimal control method on this basis. In this study, a ship’s central cooling system was mathematically modeled and verified by comparing it with the actual ship′s operation data. A control solution method to effectively save energy for the central cooling system was proposed

Üç Yollu Musluk ve Split Septumlu Enjeksiyon Valfi Kullanımının Kateter Enfeksiyonu ve Kolonizasyonuna Etkileri: Yarı Deneysel Çalışma

Objective: Connectors are frequently and necessarily used in patients undergoing intravenous fluid therapy. All of the catheters and connectors may be a risk factor for catheter infections if aseptic techniques were not used. This study was conducted to determine the effect of 3-way stopcock (3WSC) and Split Septum Injection Valve (SSIV) Usage on peripheral intravenous catheter colonization and infection. Material and Methods: This is a quasi-experimental study. The sample of the study consists of 216 patients (108 control, and 108 experimental group). 3WSC was integrated to the control group and SSIV was integrated to the experiment group peripheral venous catheters. Catheters were observed for 72 hours in terms of complications such as bleeding, leakage, and phlebitis infiltration. Catheters were removed for culture sampling 72 hours after catheterization. Descriptive statistics and Pearson chi-square were used in the analysis of the data. Results: The rate of colonization was 5.6% in 3WSCs and 2.8% in SSIVs. When the colonization rates were compared, there was no statistically significant difference between 3WSCs and SSIVs about catheter colonization and infection (p>0.05). Conclusion: Both connectors can be used safely in the administration of continuous intravenous solution and drug therapy. Development of continuous in-service training programs for the prevention of catheter related blood system infections are suggested.

Reliability of start and stop control of hydraulic actuation for the insertion of electrode arrays

Abstract Atraumatic insertions of electrode arrays (EA) into the cochlea aim to preserve natural structures and residual hearing. However, there is a limit as to how smooth and slow a surgeon can insert an EA. As a potential solution, we recently presented a tool (cochlea hydro drive, CHD) that makes use of an infusion pump to prompt and control the desired, continuous and very slow (< 1 mm/s) forward movement for such insertions. The present work further describes the onset, delay and cessation of the hydraulic actuation in response to different start and stop mechanisms, to better understand the safety of its application for cochlear implant surgery. Methods: Our previously designed tool was used to perform insertions of an EA into an artificial scala tympani model. The prototype is designed to hold an EA, which is then actuated by a standard infusion pump programmed to operate at 0.4 mm/ and 0.1 mm/s. A tubing system between the CHD and the pump includes a three-way valve. Ten insertions were operated using the functions of the pump and ten using the valve. Results: From the programmed start to the actual movement, we observed a larger average delay using the pump’s start function (5 s at 0.4 mm/s; 17 s at 0.1 mm/s) vs. opening the valve (< 0.7 s for both velocities). Moreover, the average cessation of movement with the valve closure was almost immediate (0.7 s for both velocities; this corresponds to < 0.1 mm with the slower tested velocity), as opposed to 60- 80 s delay when using the pump’s stop function. Conclusion: The use of a 3-way valve facilitates motion cessation to the high accuracy level required for cochlear implant surgery. These promising findings support future clinical translation of our tool.

A Prosthetic Socket with Active Volume Compensation for Amputated Lower Limb.

Typically, the actual volume of the residual limb changes over time. This causes the prosthesis to not fit, and then pain and skin disease. In this study, a prosthetic socket was developed to compensate for the volume change of the residual limb. Using an inflatable air bladder, the proposed socket monitors the pressure in the socket and keeps the pressure distribution uniform and constant while walking. The socket has three air bladders on anterior and posterior tibia areas, a latching type 3-way pneumatic valve and a portable control device. In the paper, the mechanical properties of the air bladder were investigated, and the electromagnetic analysis was performed to design the pneumatic valve. The controller is based on a hysteresis control algorithm with a closed loop, which keeps the pressure in the socket close to the initial set point over a long period of time. In experiments, the proposed prosthesis was tested through the gait simulator that can imitate a human’s gait cycle. The active volume compensation of the socket was successfully verified during repetitive gait cycle using the weight loads of 50, 70, and 90 kg and the residual limb model with a variety of volumes. It was confirmed that the pressure of the residual limb recovered to the initial state through the active control. The pressure inside the socket had a steady state error of less than 0.75% even if the volume of the residual limb was changed from −7% to +7%.

Correction to: Improvement of 3-Way Valve for Temperature Control of Gas Turbine Lube Oil in CCPP

The affiliation of Hyoseo Kwak has been changed to: School of Mechanlcal and Automotive Engineering, Youngsan University, Yangsan, 288, Junam-ro, Yangsan-si, Gveonasananam-do 50510 South Korea

Development of a Simple Reversible-Flow Method for Preparation of Micron-Size Chitosan-Cu(II) Catalyst Particles and Their Testing of Activity.

A simple flow system employing a reversible-flow syringe pump was employed to synthesize uniform micron-size particles of chitosan-Cu(II) (CS-Cu(II)) catalyst. A solution of chitosan and Cu(II) salt was drawn into a holding coil via a 3-way switching valve and then slowly pumped to drip into an alkaline solution to form of hydrogel droplets. The droplets were washed and dried to obtain the catalyst particles. Manual addition into the alkaline solution or employment of flow system with a vibrating rod, through which the end of the flow line is inserted, was investigated for comparison. A sampling method was selected to obtain representative samples of the population of the synthesized particles for size measurement using optical microscopy. The mean sizes of the particles were 880 ± 70 µm, 780 ± 20 µm, and 180 ± 30 µm for the manual and flow methods, without and with the vibrating rod, respectively. Performance of the flow methods, in terms of rate of droplet production and particle size distribution, are discussed. Samples of 180 µm size CS-Cu(II) particles were tested for catalytic reduction of 0.5 mM p-nitrophenol to p-aminophenol by 100-fold excess borohydride. The conversion was 98% after 20 min, whereas without the catalyst there was only 14% conversion.

Improvement of 3-Way Valve for Temperature Control of Gas Turbine Lube Oil in CCPP

Lubrication oil, which is supplied to rotating elements in gas turbines of combined-cycle power generation, is used to maintain the efficiency of electricity production. The gas turbines are exposed to high-temperature environment due to the thermal energy obtained from fossil fuel, which degrades the performance of the lubricating oil. A system for controlling the temperature of the oil is essential, but there are a few problems in the case of the temperature control valve in the system, such as the hunting phenomenon, with which the target mass flow rate cannot be achieved, fatigue fracture and leakage. In this study, finite element analysis was performed to overcome these issues. The hunting phenomenon was prevented by redesigning the orifice shape of the valve cage. The fatigue fracture and self-loosening of the clamp bolt were overcome by changing the bolt size and tightening torque. In addition, a proper O-ring was selected to prevent leakage. The performance of a prototype was also tested to verify the reliability of the finite element analysis.

Simulation and experimental research on the hydraulically powered fast switching 3-way valve for pVTt gas flow standard

pVTt has been employed as the primary gas flow standard in many countries and the performance of the inlet valve significantly influences the verification. This paper not only proposes a hydraulically powered fast switching 3-way valve but also introduces its structure and working principle. Furthermore, it builds up the flow field simulation model and conducts the dynamic simulation of its working process. As shown by the results, the designed fast switching 3-way valve could achieve the fast switching of the critical flow. In addition, the “overlapping” mode and the “non-overlapping” mode of the 3-way valve are analysed contrastively. The result reveals that the flow field of the “non-overlapping” mode is more stable. Finally, the device is tested according to the pVTt verification procedure. As indicated by the results, the switching time of two fast switching 3-way valves corresponding to DN150mm and DN100mm caliber could be controlled within 55 ms, which is consistent with the simulation results.

Design and Fabrication of an Automatable, 3D Printed Perfusion Device for Tissue Infusion and Perfusion Engineering.

Tissue decellularization for generating extracellular matrices has become a staple of regenerative medicine in the recent decades, extending from the research setting to clinical usage. Although methods and protocols for tissue decellularization are abundant throughout the literature, they can be time intensive and typically require specific overhead in terms of equipment. To reduce these barriers to entry, a functional and reproducible prototype of a tissue infusion/perfusion device (TIPD) has been designed and fabricated using three-dimensional printed parts in conjunction with commercially available components. This TIPD forms a system composed of two peristaltic pumps, two 3-way valves, and a chamber in which tissue is contained, and is controlled by user-customizable software. To increase repeatability among decellularization protocols, an automation function has been integrated into the software, which is able to specify fluid flow rates and define specific valve locations enabling selection of solutions to be introduced into a scaffold over the course of a decellularization process. The prototype has been tested for proof of concept through infusion and perfusion decellularization of skeletal muscle and intact kidneys, respectively, and has shown successful removal of cellular content while maintaining an intact ultrastructure. In an effort to increase the reproducibility of experimental designs and to promote an open source hardware initiative in the field of tissue engineering, a novel device was conceptualized and prototyped with printable part files made available for its fabrication in tandem with instructions for assembly. Impact Statement Repeatable methods for decellularization are essential for achieving consistent substrates between batches, laboratories, and facilities. To meet this end, an automatable tissue infusion/perfusion device composed of three-dimensional printed parts and commercially available components has been prototyped and tested. Materials and instructions for its assembly have been made available in an effort to reduce variability among equipment as well as to provide a platform on which to iterate open-source hardware in tissue engineering.

Determination of Fe, Ti in Seawater Using a Flow-injection Pretreatment System with ICP-MS

Ge, H.; Chen, D.; Li, S.; Zheng, A.; Zhu, Z., and Zheng, X., 2019. Determination of Fe, Ti in seawater using a flow-injection pretreatment system with ICP-MS. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 77–82. Coconut Creek (Florida), ISSN 0749-0208.In order to solve the interference caused by low metal concentration and salts matrix of seawater samples, this paper present a handy flow- injection system with solid-phase extraction to automate pretreatment procedures for offline Fe and Ti analysis in seawater by ICP-MS. By combining 8-position, 3-way and 6-way valves in the pipeline, the flow-injection system enhance the sample treatment efficiency by simultaneously loading two reagents online for: sample loading, buffering, and preconcentration. Each sample treatment spends about 16 min and consumes 12 mL of seawater sample and 8 mL of buffer solution. The chelation of Toyopearl-AF-Chelate-650M for Fe and Ti occurs in pH5.5 at an injection rate of 1.0 mL·min-1. The eluent (0.8 mol·L-1 HNO3) is able to elute Fe and Ti in 90 s at an elution rate of 1.0 mL·min-1. Seawater sample needs 90 min of 120 W UV-oxidation to dissociate metal-organic complexes. The precision and availability of this method are tested by measuring Jiulongjiang Estuary seawater samples.

Effect of high-frequency oscillation on pressure delivered by high flow nasal cannula in a premature infant lung model.

This study describes the effect of high-frequency oscillation on airway pressure generated by high flow nasal cannula (HFNC) in a premature infant lung model. A premature in 0.5 or 1.0 mL/cmH 2 O, respiratory rate (RR) of 40 or 60 breaths per min, and tidal volume of 6 mL. Oscillation was achieved by passing the HFNC supply flow through a 3-way solenoid valve operating at 4, 6, 8, or 10 Hz. Airway pressure at the simulated trachea was recorded following equilibration of end-tidal CO 2 both with and without oscillation. Superimposing high-frequency oscillations onto HFNC resulted in an average decrease in mean airway pressure of 17.9% (P = .011). The difference between the maximum and minimum airway pressures, ∆ P min-max, significantly increased as oscillation frequency decreased ( P < .001). Airway pressure during oscillation was 12.8% greater with the 1.0 vs the 0.5 mL/cmH 2 O compliance at flows > 4 L/min ( P = .031). CO 2 clearance was 13.1% greater with the 1.0 vs 0.5 mL/cmH 2 O compliance at oscillation frequencies less than 8 Hz ( P = .015). In this in-vitro study we demonstrate that delivered mean airway pressure decreases when applying high-frequency oscillation to HFNC, while still improving CO2 clearance. The combination of improved CO 2 clearance and reduced pressure delivery of this novel noninvasive modality may prove to be a useful improvement in the respiratory care of infants in respiratory distress.

Myocardial Monophasic Action Potential Recorded by Suction Electrode for Ionic Current Studies in Zebrafish.

The study of myocardial transmembrane ion currents is fundamental to understand frequent pathologies such as arrhythmias and ischemia. Conventional electrocardiography (ECG) is not able to record ion currents, while the use of intracellular microelectrodes in a beating heart has technical limitations. Myocardial monophasic action potentials (MAPs) recorded with suction electrodes allow the evaluation of ionic currents similar to those recorded by intracellular glass microelectrodes. The technique is based on the fact that suction, through a small diameter tube, on the myocardial cell, induces an opening at the membrane, connecting the intracellular media to the electrode by a saline bridge. The electrophysiology of zebrafish heart is remarkably similar to the human; however, in situ evaluation of MAPs has not been yet explored. In this study, we aimed to establish a myocardial MAP recording technique for adult zebrafish. Male adult wild-type zebrafish were anesthetized and 50% of the beating ventricle was exposed. A glass hematocrit capillary tube (1.1 mm inner diameter) was used as a suction electrode connected to a 3-way stopcock valve, which is also connected to a syringe containing a chloride-coated silver wire for signal recording. Gentle suction was exerted by a syringe filled with ringer and connected to the 3-way stopcock valve. Two needles were used for ground (tail) and indifferent (abdomen) electrodes. Without suction, the system can record conventional ECG, but applying suction MAPs are registered and show typical morphology with phase 0-4 sequence. MAP amplitude and duration values show low variability. Ischemia and/or lidocaine-induced Na+ channel blocking dramatically reduced MAP amplitude. These results strongly suggest that the suction electrode technique is a promising method to record myocardial ion currents in situ in zebrafish.

Breath Collection from Children for Disease Biomarker Discovery.

Breath collection and analysis can be used to discover volatile biomarkers in a number of infectious and non-infectious diseases, such as malaria, tuberculosis, lung cancer, and liver disease. This protocol describes a reproducible method for sampling breath in children and then stabilizing breath samples for further analysis with gas chromatography-mass spectrometry (GC-MS). The goal of this method is to establish a standardized protocol for the acquisition of breath samples for further chemical analysis, from children aged 4-15 years. First, breath is sampled using a cardboard mouthpiece attached to a 2-way valve, which is connected to a 3 L bag. Breath analytes are then transferred to a thermal desorption tube and stored at 4-5 °C until analysis. This technique has been previously used to capture breath of children with malaria for successful breath biomarker identification. Subsequently, we have successfully applied this technique to additional pediatric cohorts. The advantage of this method is that it requires minimal cooperation on part of the patient (of particular value in pediatric populations), has a short collection period, does not require trained staff, and can be performed with portable equipment in resource-limited field settings.

Experimental Study of Optimum Chilled Water Distribution Configuration in Air Conditioning Terminal Unit Using RSM Technique

The distribution of chilled water flow rate in terminal unit is an important factor used to evaluate the performance of central air conditioning unit. A prototype of A/C unit has been made, which contains three terminal units with a complete set of accessories (3-way valve, 2-way valve, and sensors) to study the effect of the main parameters, such as total water flow rate and chilled water supply temperature with variable valve opening. In this work, 40 tests were carried out. These tests were in two groups, 20 test for 3-way valve case and 20 test for 2-way valve case. These tests were performed at three levels of valve opening, total water flow rate and water supply temperature according to the design matrices established by Design of Experiment (DOE) software 'version 7' with Response surface methodology (RSM) technique. The model was conducted for each case of total heat rate, then checked statistically for adequacy by Analysis of variance (ANOVA), and found good with 95% confidence level. The results showed that the water supply temperature has a significant effect on the total heat rate of two cases. It was found that the optimum solution for maximum total heat rate and minimum flow deviation represented by standard deviation was obtained at 10°C water supply temperature, 5.5 l/min total water flow rate and 70% valve opening. The total heat rate and standard deviation were (890.249 Watt), (0.000513), respectively in three-way valve case and (743.155 Watt), (0.00277), respectively in two-way valve case. Finally, the predicted and experimental results of total heat rate and standard deviation were in agreement with a maximum error of 6.6 % in three-way valve case and 1.4% in two-way valve case.&#x0D;

The oil pressure test of the hydraulic impeller blade

This article introduced the structure of the Kaplan runner in hydropower station and the operating process of the oil pressure test has been described. What’s more, the whole process, including filling oil to the runner hub, the movement of the runner blade, the oil circuit, have been presented in detail.Since the manipulation of the oil circuit which controlled by three Valve groups consisting of six valves was complicated, the author is planning to replace them with 3-position 3-way electromagnetic valves, so we can simplify the operation procedure.The author hopes this article can provide technical reference for the oil pressure test.

유동해석을 통한 선박용 디젤엔진(LDCL JWCS)의 3-Way Valve 형상 설계

기존의 선박용 디젤 엔진에는 항상 일정한 엔진 부하량을 유지하는 캠 구동장치가 적용되고 있었으나, 최근 환경규제로 인하여 엔진 부하량에 따라 실린더 온도를 개별적으로 제어하는 LDCL(Load dependent cylinder liner) JWCS(Jacket water cooling system)가 적용된 전자유압 제어방식이 개발되었다. 이 시스템에서 3-way 밸브는 실린더의 상부와 하부와의 온도 차이를 줄여 저온부식을 방지하는데, 대부분 수입에 의존하고 있으며 토출유량이 낮다. 이에 본 연구에서는 3-way 밸브 내부 형상 관련 설계인자가 성능(토출 유량 및 온도)에 미치는 영향을 파악하여 밸브의 형상 설계를 수행하였으며, 기존 모델과의 성능 비교를 통해 제안된 밸브의 우수성을 검증하였다.