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Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments. In recent years, such methods have been widely used in metal mines where pipeline transportation typically plays a decisive role in the safety and stability of the entire filling system. Because the filling slurry contains a large percentage of solid coarse particles, the involved pipeline is typically eroded and often damaged during such a process. A possible solution is the so-called nesting repair technology. In the present study, nesting a 127 mm outer diameter pipeline in 151 mm inner diameter borehole is considered to meet the repair objective. First, by using the rheological theory, the pipeline transmission resistance and self-flow conveying range are calculated under different working conditions. It is shown that the pipeline transmission resistance is larger when the inner diameter of casing is 80 mm, and the limit flow rate of vertical pipeline self-flow is 120 m3/h; moreover, when the pipeline diameter is 100 mm and the flow rate is 140 m3/h, the self-flow conveying can be satisfied in most of the underground −455 m stage. Accordingly, a plan is presented for the nesting repair strategy, based on the installation of a drill bit under the casing and lowering the casing into the borehole as if it were a drill pipe. Finally, the outcomes of such a strategy are verified. The filling flow rate range using the new pipelines is found to be in the range from 188.60 to 224.39 m3/h, and its average filling flow rate reaches 209.83 m3/h when conveying 2319.6 m long-distance quarry. [ABSTRACT FROM AUTHOR]

The influence of silo width on dense granular flow in a two‐dimensional silo is investigated through experiments and simulations. Though the flow rate remains stable for larger silo widths, a slight reduction in silo width results in a significant increase in flow rate for smaller silo widths. Both Beverloo's and Janda's formula accurately capture the relationship between the flow rate and outlet size. Flow characteristics in the regions near the outlet exhibit local self‐similarity, supporting Beverloo and Janda's principles. Moreover, global self‐similarity is analyzed, indicated by the transition in flow state from mass flow in regions far from the outlet to funnel flow near the outlet. The earlier occurrence of this transition favors to enhance the grain velocity and consequently increases the dense flow rate. An exponential scaling law is proposed to describe the dependencies of flow rate, grain velocity, and transition height on silo width. [ABSTRACT FROM AUTHOR]

Using a segmented holding system can effectively reduce cracking and wrinkling in the stamping process and improve the forming limit of stamped parts. Different segmentation schemes can be achieved flexibly using a blank holding system driven by electromagnetics. However, how to segment the blank holder to fulfill the demand for flow control of complex parts is still an obstacle to overcome. This paper proposes a flow rate-based design of distributed blank holders on demand for complex parts. A theoretical model is first established to analyze the differences in flow rate in the flange. Then, the flow rates are identified circumferentially and radially to find the locations where the changes in rates are large, and these locations are lined and deemed as the boundaries for segmenting holders. Moreover, a design implementation, including location identification and the electromagnetic system configuration for complex parts, is developed to explore the optimal segmentation schemes. To validate the effectiveness, the downscaling part of a car door with the material DP600 is selected to find the segmented scheme, and the corresponding prototypes of integral and segmented electromagnetic dies are then configured. Experimental results show that the thickening ratio is decreased by 15.4%, and the thinning ratio is increased by 22.5% compared with that of the integral blank holder, and the design achieves better quality and fewer segmented pieces compared with the conventional approach. This research assists in designing segmented blank holding systems enabled by electromagnetics and provides a universal segmentation approach to form better-quality complex parts. [ABSTRACT FROM AUTHOR]

Background: Effective endodontic treatment requires the use of a root canal sealer with optimal properties to ensure a hermetic seal, prevent reinfection, and promote healing. Despite the availability of various sealers, a standardized evaluation system still needs to be improved. Objectives: To develop a Clinical Utility Index (CUI) that systematically evaluates and ranks root canal sealers based on their sealing ability, antimicrobial efficacy, flow rate, and solubility. Methods: The CUI was developed through a structured process involving expert identification, panel discussions, and the establishment of scoring criteria. Five sealers were evaluated (Sealers A, B, C, D, and E). Mean values for the core properties were calculated, and sealers were ranked accordingly. The total CUI for each sealer was computed based on the assigned scores for each property. Results: Sealer B achieved the highest CUI at 95%, demonstrating superior performance across all core properties. Sealer C followed with a CUI of 80%, while Sealer A ranked third with 60%. Sealers D and E showed the lowest performance, with CUIs of 30% and 35%, respectively, highlighting deficiencies in multiple properties. Discussion: The CUI provides a comprehensive evaluation framework for root canal sealers, facilitating informed decision-making by practitioners. Sealer B's high CUI underscores the importance of balancing sealing ability, antimicrobial effect, flow rate, and solubility. The results align with existing literature emphasizing the critical role of these properties in endodontic success. Conclusion: The CUI offers a robust and balanced method for evaluating root canal sealers, aiding in selecting the most suitable sealer based on empirical data. Future research should refine the index and validate its applicability in diverse clinical scenarios to enhance endodontic treatment outcomes. [ABSTRACT FROM AUTHOR]

[Objective] In order to optimize the process of long stem yield and improve the long stem yield in tobacco leaf processing. [Method] Taking the middle leaf of Shaanxi-Gansu flue-cured tobacco as test materials and taking flow rate, three beating roller speed, four beating roller speed as the objects, by the principle of full factor experiments and DOE analysis method, mathematical regression models between long stem yield and flow rate, three beating roller speed, four beating roller speed were constructed. [Result] The results showed that: flow rate, three beating roller speed, four beating roller speed and interaction of flow rate with three beating roller speed had significant influence on the long stem yield, the interaction of flow rate with four beating roller speed and the interaction of three beating roller speed with four beating roller speed had no significant influence on the long stem yield. There was an effective regression model between long stem yield and flow rate, three beating roller speed, four beating roller speed and interaction of flow rate with three beating roller speed. When flow rate was 9 500 kg/h, three beating roller speed was 650 r/min, and four beating roller speed was 750 r/min, the average long stem yield reached the maximum value of 15.285 0% and the best. [Conclusion] Comprehensive comparison suggested that there is a certain regression relationship between long stem yield and flow rate, three beating roller speed, four beating roller speed, the optimal parameters of flow rate, three beating roller speed, four beating roller speed for long stem yield were determined through the certain regression relationship. [ABSTRACT FROM AUTHOR]

Water desalination technology has emerged as a critical area of research, particularly with the advent of more cost-effective alternatives to conventional methods, such as reverse osmosis and thermal evaporation. Given the vital importance of water for life and the scarcity of potable water for agriculture and livestock—especially in the Kingdom of Saudi Arabia—the capacitive deionization (CDI) method for removing salt from water has been highlighted as the most economical choice compared to other techniques. CDI applies a voltage difference across two porous electrodes to extract salt ions from saline water. This study will investigate water desalination using CDI, utilizing a compact DC power source under 5 volts and a standard current of 2 amperes. We will convert waste materials like sunflower seeds, peanut shells, and rice husks into activated carbon through carbonization and chemical activation to improve its pore structure. Critical parameters for desalination, including voltage, flow rate, and total dissolved solids (TDS) concentration, have been established. The initial TDS levels are set at 2000, 1500, 1000, and 500 ppm, with flow rates of 38.2, 16.8, and 9.5 mL/min across the different voltage settings of 2.5, 2, and 1.5 volts, applicable to both direct and inverse desalination methods. The efficiency at TDS concentrations of 2000, 1500, and 1000 ppm remains between 18% and 20% for up to 8 min. Our results indicate that the desalination process operates effectively at a TDS level of 750 ppm, achieving a maximum efficiency of 45% at a flow rate of 9.5 mL/min. At voltages of 2.5 V, 2 V, and 1.5 V, efficiencies at 3 min are attained with a constant flow rate of 9.5 mL/min and a TDS of 500 ppm, with the maximum desalination efficiency reaching 56%. [ABSTRACT FROM AUTHOR]

With the intensification of global climate change, extreme rainfall events are occurring more frequently. Continuous rainfall causes the debris flow gully to collect a large amount of rainwater. Under the continuous increase in the water level, the water flow has enough power to carry plenty of loose solids, thus causing debris flow disasters. The intensity of the soil is reduced with the infiltration of rainwater, which is one of the key causes of the disaster. The rise in the water level affects the infiltration behavior. There have been few previous studies on infiltration under variable head. In order to understand the infiltration behavior of soils under the action of water level rises, this paper conducted an indoor permeability test on non-cohesive soil under the condition of an increasing water level. A numerical model was established using the finite element analysis software, Abaqus 6.14, and the pore pressure was increased intermittently to simulate the intermittent increase in the water level. Thereafter, the permeability coefficient and seepage length were changed to interpret the changes in the flow velocity and rate in the permeability test of the non-cohesive soil. The results showed that the finite element numerical simulation method could not reflect the particle movement process in the soil. The test could better reflect the through passage and void plugging phenomenon in soil; when the permeability coefficient alone changed, the velocity of the measuring point with higher velocity changed more violently with the permeability coefficient; when the length of soil seepage diameter was uniformly shortened, the velocity of water flow increased faster and faster. [ABSTRACT FROM AUTHOR]

Context: In a very small surface separation, the fluid flow is actually multiscale consisting of both the molecular scale non-continuum adsorbed layer flow and the intermediate macroscopic continuum fluid flow. Classical simulation of this flow often takes over large computational source and is not affordable owing to using molecular dynamics simulation (MDS) to model the adsorbed layer flow, if the flow field size is on the engineering size scale such as of 0.01–10 mm or even bigger like occurring in micro or macro hydrodynamic bearings. The present paper uses full MDS to validate Zhang's multiscale flow model, which yields the closed-form explicit flow equations respectively for the adsorbed layer flow and the intermediate continuum fluid flow. Here, full MDS was carried out for the pressure-driven flow of methane in the nano slit pore made of silicon respectively with the channel heights 5.79 nm, 11.57 nm, and 17.36 nm. According to the number density distribution, the flow areas were respectively discriminated as the adsorbed layer zone and the intermediate fluid zone. The values of the characteristic parameters for Zhang's multiscale scheme were extracted from full MDS and input to Zhang's multiscale flow equations respectively for calculating the flow velocity profile and the volume flow rates of the adsorbed layers and the intermediate fluid. It was found that for these three channel heights, the flow velocity profiles calculated from Zhang's model approximate those calculated from full MDS, while the total flow rates through the channel calculated from Zhang's model are close to those calculated from full MDS. The accuracy of Zhang's multiscale flow model is improved with the increase of the channel height. Method: The recent modification of the optimized potential for liquid simulation (MOPLS) model was used to calculate the interaction force between two methane molecules. In order to calculate the interaction force between the wall atoms and the methane molecules accurately, our previous non-equilibrium multiscale MDS was used. The interaction forces between the methane molecule and the wall atom were obtained from the coupled potential function by the L-B mixing rule when the fluid molecules arrived at near wall. The methane molecule diameter was obtained from the radial distribution function by using equilibrium MDS under the same initial conditions. The local viscosities across the adsorbed layer were obtained from the local velocity profile by using the Poiseuille flow method. The motion equation of the methane molecule was solved by the leapfrog method. The temperature of the simulation system was checked by Bhadauria's method, i.e., the system temperature was rectified by the velocities in the y- and z-directions. The flow velocity distributions across the channel height and the volume flow rates through the channel were also calculated from Zhang's closed-form explicit flow equations respectively for the adsorbed layer flow and the intermediate fluid flow. The results respectively obtained from full MDS and Zhang's multiscale flow equations were then compared. [ABSTRACT FROM AUTHOR]

Cruise-type aquaculture on deep-sea aquaculture vessels is an important direction for developing of modern marine fisheries. The article explored the effect of transverse rolling motion on the flow field characteristics in the tank based on FLOW-3D software, and calculated the removal of waste particles in the flow field under different transverse rolling conditions on this basis. The results showed that when controlling the period of transverse rolling, the flow velocity in the aquaculture tank increased slightly as the amplitude of the transverse rolling angle increased from 0° to 2°. When the amplitude of the transverse rolling angle was increased from 2° to 7º, the flow velocity in the aquaculture tank showed a large increase, and the v50% increased from 0.171 m/s to 0.477 m/s; the increase of the transverse rolling angle also made the overall distribution of the flow velocity more discrete. The flow uniformity index of the conditions with the transverse rolling angle amplitude of 2° or less is mainly concentrated in 0.8-0.85, while when the transverse rolling angle amplitude is increased to 3º, the flow uniformity of the aquaculture tank decreases significantly. The flow uniformity indices of the water in the aquaculture tank are all less than 0. 8. When the amplitude of the transverse rolling angle is certain, the transverse rolling period is shortened, the flow velocity in the aquaculture tank increases sharply, and the v50% of the flow velocity of each condition and the other quartiles show a linear growth trend while the uniformity of the flow of the water in the tank does not change significantly. For the removal of waste solid particles in the aquaculture tank, the whole process is divided into two phases with opposite effects when the period of transverse rolling and the properties of particles themselves are certain. From the time when the particles were released into the flow field to the 1000 s after the release, the smaller the amplitude of the transverse rolling angle was, the higher the removal rate was; thereafter, until the end of the calculation of the whole example, the larger the transverse rolling angle was, the higher the removal rate of the particles was. The period of transverse rolling did not effect the removal of particles in the aquaculture tanks, and the time to reach the standard for particles removal was very close for each condition. [ABSTRACT FROM AUTHOR]

Enhancing the utilisation rate and productivity of saline-alkali land is critical in ensuring sufficient cultivated land resources and food security. Although drip irrigation technology maintains the crop yield in saline-alkali land, the irrigation water amount must be higher than the crop demand. To address this, the present study develops a novel variable discharge emitter (VDE), which consists of an upper cover, a bottom cover, and a diaphragm with a linear incision. The experimental results showed that the VDE achieved two rated discharge levels of 4.1 L h−1 and 9.7 L h−1 when the working water pressure was at 0.10 MPa and 0.16 MPa and when the length of the incision, the thickness of the diaphragm, and the hardness of diaphragm inside the VDE were 3.5 mm, 1.5 mm, and 55.0 HA, respectively. It suggests that VDE has two rated discharges for irrigation and salt-leaching based on two working water pressure ranges. • A variable discharge emitter (VDE) for irrigation and salt-leaching is developed. • Linear incision on diaphragm inside the emitter can achieve two discharge levels. • VDEs spacing in lateral of drip irrigation system should be no less than 1.0 m. [ABSTRACT FROM AUTHOR]

• Semi-empirical models for suction flow rate, injection flow rate, input power consumption, and discharge temperature are proposed for scroll compressors with vapor injection. • The modeling approach can be consistently applied to fixed-speed and variable-speed compressors. • The models were fit and evaluated using a data set containing four compressors. The prediction accuracy is similar to other proposed models and the model requires relatively low testing effort to fit the empirical parameters. • The models were applied to one compressor for operation with and without vapor injection. The prediction errors for both modes of operation are similar, while only using one set of model parameters. Semi-empirical models for predicting the suction flow rate, injection flow rate, input power consumption, and discharge temperature are proposed for scroll compressors with vapor injection. A data set containing four compressors wherein each compressor was tested over a range of operating conditions is used to evaluate the models. The fitted parameters of the models and the prediction errors of each data set are discussed. The accuracy and generalizability of applying the models to the same compressor with and without vapor injection are also discussed. [ABSTRACT FROM AUTHOR]

The escalating demand for water and the increasing pollution of natural water bodies necessitate innovative solutions for wastewater treatment and reuse. This study investigated the potential of a horizontal subsurface flow (HSSF) constructed wetland to treat aquaculture wastewater for reuse. The system, planted with Taro (Colocasia esculenta) and sugarcane (Saccharum officinarum L.), received effluent from a recirculating aquaculture system (RAS) producing African Catfish (Clarias gariepinus). The study assessed the impact of varying hydraulic retention times (1-3 days) and flow rates (11-108 L/min) on water quality parameters, including dissolved oxygen, electrical conductivity, salinity, total dissolved solids, temperature, and pH. Results showed significant increase in dissolved oxygen (4.25-5.52 mg/L), while electrical conductivity (491-677 µS/cm), salinity (0.23-0.32 ppt), and total dissolved solids (237-332 mg/L) decreased considerably. Temperature (29.28-31.07 °C) and pH (7.57-7.59) remained stable and within acceptable ranges for reuse in African Catfish production. However, retention time and flow rate did not significantly affect treatment efficiency within the tested parameters. Further research is recommended to explore the impact of longer retention times, wider flow rate ranges, different plant species and substrate types, and microbial community analysis to optimize the system's performance and promote sustainable aquaculture practices. [ABSTRACT FROM AUTHOR]

Silicone rubber (SiR) has become a reliable choice for outdoor high voltage (HV) insulation in recent years. However, the durability of these polymeric materials is affected by both electrical and environmental stresses, leading to aging. While prior research aimed at enhancing performance, little focus was placed on identifying the major root causes of aging in these insulators. To delve into the causes, we conducted inclined plane tracking (IPT) tests, varying voltage, flow rate, and contamination concentration. Samples with consistent alumina trihydrate (ATH) filler content were tested under the BSEN 60587 standard. The voltage ranged from 3.5-5.5 kV, flow rate from 0.3-0.9 ml/min, and contamination concentration from 500-4500 µS/cm. A Two-Level Factorial analysis with a design of experiment (DOE) approach was used. The study revealed that contaminant concentration significantly impacted leakage current (LC), followed by contamination flow rate and voltage. Additionally, optimization techniques are used to determine ideal LC values under specific conditions. This study explains how each factor affects LC values, allowing for predictive modelling, which improves our understanding of SiR insulators' durability, optimizes LC in real-world situations, and improves their performance and lifespan. [ABSTRACT FROM AUTHOR]

In the period of processing and storage of grain production, losses due to leakage of grain are observed during its movement between machines and installations and during storage in bunkers and silos. Scattering is mainly the result of leakage of grain and seeds through cracks, crevices, holes in machinery and equipment. Losses from the leakage of grain and seeds through openings of different shapes and sizes have been investigated. Boundary dimensions of openings of different shape and size have been defined, through which the flow of grain and seeds from various crops is stopped. Mathematical models of the rate of grain and seeds losses due to leakage through different openings have been obtained. The adequacy of the models for practice have been evaluated. [ABSTRACT FROM AUTHOR]

Optimizing the heat extraction performance of geothermal systems is a long-standing issue in the study of geothermal energy. Besides the heat extraction in fractured hot rock, minimizing the heat loss during water flowback through boreholes is also critical for the system performance. Here, we conducted a series of experimental and numerical studies to understand the controlling factors of heat extraction rate and efficiency and to explore practical approaches for the optimization of heat extraction performance in a geothermal borehole. We performed water flow experiments to observe the heat extraction from neighboring hot granite and reproduced the heat extraction process using a three-dimensional water flow model. Our results show that the heat extraction rate first increases with a higher flow rate to the maximum value and then decreases with a further rise in flow rate. The heat extraction efficiency decreases constantly with a higher flow rate. To improve the heat extraction performance with both the heat extraction rate and efficiency approaching the maximum values, we scaled up the laboratory-scale borehole and found that the heat extraction performance is enhanced with a triangular zone of heat extraction and a reduced zone of low-temperature water along a field-scale borehole. We finally discovered that a proper control of borehole geometry, such as section diameters along a multi-section borehole and bending angle of borehole trajectory, is a feasible strategy to modulate the heat extraction performance in a geothermal borehole and to replenish the heat loss during water flowback. Highlights: Experimental and numerical studies are conducted to understand the controlling factors of heat extraction rate and efficiency. Heat extraction performance is enhanced with a triangular zone of heat extraction and a reduced zone of low-temperature water. Multi-section borehole is a feasible strategy to modulate the heat extraction performance in a geothermal borehole. Proper bending angle of borehole trajectory is another feasible strategy to optimize the heat extraction performance. [ABSTRACT FROM AUTHOR]

Background: Keeping in mind the unceasingly escalating prevalence of coronary disease worldwide, the mortality rate is also expected to rise with a staggering increase in healthcare costs. Angiography is the gold standard for diagnosing these blockages that trigger these diseases. Amides and urethanes are the common catheter construction material used for angiography. However, the experimental evidence verifying the use of PEBAX® and comparing its performance with that of commercially available catheters for angiography is not published despite it being well recognized for its excellent flexural modulus, mechanical properties, and biocompatibility and its potential to reduce the incidence of vascular spasm during intravascular diagnostic and interventional procedures. Therefore, the aim of this study was to develop a PEBAX®-based angiographic catheter and evaluate its performance in comparison with three commercially available nylon- and polyurethane-based angiographic catheters. Methodology: A PEBAX®-based angiographic catheter was developed for this purpose. This study analyzes and reports the performance and behavior of PEBAX®-, nylon-, and polyurethane-based catheters. The catheter's performance and arterial forces' endurance nature were mapped out by evaluating pushability (advancement force) and selective bench tests outlined in the applicable regulatory standard. Conclusions: The PEBAX®-based catheter exhibited the least bond-flexural rigidity (180.4 g), which was approximately one-third of that shown by all six French catheters and which exhibited the least advancement force (510.4 g), which was approximately 50% less than that of the nylon- and polyurethane-based catheters when traversing through the mock arterial system. Bench testing was carried out as per the applicable regulatory standard; the differences obtained between individual catheters were discussed in detail. Based on this extensive in vitro assessment, it was concluded that the PEBAX®-based catheters outperformed the nylon- and polyurethane-based catheters, exhibiting an exceptionally minimal advancement force of 510.4 g. This leads to the inference that this catheter can inject more radiopaque material (because of the enhanced flow rate) to the coronary arteries and can play a significant role in minimizing vascular spasms during a diagnostic procedure. [ABSTRACT FROM AUTHOR]

Pipeline infrastructure plays a critical role in the transportation of vital resources, including oil, gas, and water. However, pipeline failures and leaks can have devastating consequences, resulting in environmental damage, economic losses, and risk to human life. Traditional methods of leak detection, such as visual inspection and pressure testing, are often time-consuming, labor-intensive, and unreliable. With the advent of wireless sensor networks (WSNs), there is an opportunity to revolutionize pipeline monitoring and leak detection. In this paper, we present a system that can monitor and detect leakage early, to enable engineers carry out prompt maintenance. This is made possible by the use of a network of nodes in a WSN, placed along a pipeline, each of which is capable of measuring and reporting varying flow rates, indicative of possible leakages. The system design consists of three major layers namely, the nodes layer, the cloud layer (for data logging), and the reporting layer. Tests were conducted under various conditions. The results show that with no leakages, the average flow rates for nodes 1, 2, 3, and 4 were 16.89747978, 16.89935602, 16.90978163, and 16.93380634 respectively. Furthermore, percentage flow rate differences of -0.02550353, 29.959675, and 30.3944134 were recorded for nodes 2, 3, and 4 respectively, after leakages occurred. The high values of the percentage difference for nodes 3 and 4 indicate a significant discrepancy in flow rate, worthy of physical inspection. The system is capable of detecting faults and leakages, even in the event of sensor failure, or network disruption. [ABSTRACT FROM AUTHOR]

Hydraulic pumps are the heart of hydraulic systems that convert electrical energy into mechanical energy. As the behavior of a specific type of hydraulic pump must be identified to cater to the pump's limits and operating range, precise pump selection for particular applications is a must. Hence, this paper presents the research findings on the characteristics of hydraulic pumps, focusing on pump parameters such as pump power, flow rate, and operating pressure. These parameters were evaluated under no-load operating conditions without actuators. The simulation setup is realized through Simscape on the MATLAB platform. The laboratory test rig exploits the advantages of Bosch Rexroth hydraulic pumps and other hydraulic components manufactured by the Rexroth group of companies. The findings from this research find a relationship between pump power, pressure, and flow rate. The simulation and experimental results showed good agreement with a very slight percentage difference, where the factors that contribute to the slight tolerance are thoroughly elaborated.

Abstract Background Effective endodontic treatment requires the use of a root canal sealer with optimal properties to ensure a hermetic seal, prevent reinfection, and promote healing. Despite the availability of various sealers, a standardized evaluation system still needs to be improved. Objectives To develop a Clinical Utility Index (CUI) that systematically evaluates and ranks root canal sealers based on their sealing ability, antimicrobial efficacy, flow rate, and solubility. Methods The CUI was developed through a structured process involving expert identification, panel discussions, and the establishment of scoring criteria. Five sealers were evaluated (Sealers A, B, C, D, and E). Mean values for the core properties were calculated, and sealers were ranked accordingly. The total CUI for each sealer was computed based on the assigned scores for each property. Results Sealer B achieved the highest CUI at 95%, demonstrating superior performance across all core properties. Sealer C followed with a CUI of 80%, while Sealer A ranked third with 60%. Sealers D and E showed the lowest performance, with CUIs of 30% and 35%, respectively, highlighting deficiencies in multiple properties. Discussion The CUI provides a comprehensive evaluation framework for root canal sealers, facilitating informed decision-making by practitioners. Sealer B's high CUI underscores the importance of balancing sealing ability, antimicrobial effect, flow rate, and solubility. The results align with existing literature emphasizing the critical role of these properties in endodontic success. Conclusion The CUI offers a robust and balanced method for evaluating root canal sealers, aiding in selecting the most suitable sealer based on empirical data. Future research should refine the index and validate its applicability in diverse clinical scenarios to enhance endodontic treatment outcomes.

A new method of adaptive control of infusion during phacoemulsification (PE) based on the Optimed Profi (Optimedservice) surgical system was developed, allowing calculation of the predicted volume of post-occlusion surge (POS) by monitoring aspiration and infusion flow rates. Purpose. To compare POS amplitude, predicted and actual volumes of POS during experimental ex vivo PE on cadaveric porcine eyes, between Optimed Profi and Centurion Vision surgical systems. Material and methods. For two experimental PE series of 10 operations on porcine eyes, the mean POS amplitude (mm Hg) was measured using a pressure sensor in the anterior eye chamber. Predicted and actual POS volumes were assessed using a non-contact aspiration-line flowmeter sensor by varying aspiration flow rate depending on the phaco needle patency. The parameters were compared between the series using the Student t-test. Results. The mean POS amplitude during PE by Optimed Profi and Centurion Vision System was 12.10 ± 0.21 and 13.3 ± 0.3 mm Hg, respectively (p < 0.001). The mean value of the predicted POS volume during PE by Optimed Profi and Centurion Centurion Vision System was 136.80 ± 9.59 and 146.00 ± 9.46 μm, respectively (p > 0.01). The mean value of the actual POS volume during PE by Optimed Profi and Centurion Vision System was 135.30 ± 4.97 and 158.50 ± 8.63 μm, respectively (p < 0.01). Conclusion. The lower values of POS amplitude and predicted and actual volumes of POS in the series using the new method of adaptive infusion control may indicate a better hydrodynamic stability in experimental PE.

The escalating demand for water and the increasing pollution of natural water bodies necessitate innovative solutions for wastewater treatment and reuse. This study investigated the potential of a horizontal subsurface flow (HSSF) constructed wetland to treat aquaculture wastewater for reuse. The system, planted with Taro (Colocasia esculenta) and sugarcane (Saccharum officinarum L.), received effluent from a recirculating aquaculture system (RAS) producing African Catfish (Clarias gariepinus). The study assessed the impact of varying hydraulic retention times (1-3 days) and flow rates (11-108 L/min) on water quality parameters, including dissolved oxygen, electrical conductivity, salinity, total dissolved solids, temperature, and pH. Results showed significant increase in dissolved oxygen (4.25-5.52 mg/L), while electrical conductivity (491-677 µS/cm), salinity (0.23-0.32 ppt), and total dissolved solids (237-332 mg/L) decreased considerably. Temperature (29.28-31.07 °C) and pH (7.57-7.59) remained stable and within acceptable ranges for reuse in African Catfish production. However, retention time and flow rate did not significantly affect treatment efficiency within the tested parameters. Further research is recommended to explore the impact of longer retention times, wider flow rate ranges, different plant species and substrate types, and microbial community analysis to optimize the system's performance and promote sustainable aquaculture practices.

Based on the concept of green low-carbon and high-efficiency smelting, Fe-C alloys were prepared using industrial pure iron and high-purity graphite powder, and thermal experiments were carried out using a high-tem perature tube furnace, and it was found that with the increase of blowing time, the carbon content in the molten pool was reduced subsequently; The reaction rates of CO2 with (C) were 11,03 %, 12,94 %, 16,51 %, and 18,75 % at blowing flow rates of 10, 20, 30, and 40/ml·min-1, respectively; The decarburization rate increased from 0,0172 %/min to 0,0289 %/min, and the decarburization reaction rate is subsequently increased 1,68 times.

In this paper, a valve piezoelectric pump structure is proposed, which provides a method for the cooling of metallurgical equipment and avoids the hidden danger of damage to key components due to long-term exposure to high temperatures. In this paper, the research results of simulated flow rate and test flow rate of valved piezoelectric pump are introduced. The results show that the flow rate of the pump is sensitive to the influence of driving voltage, and it has certain feasibility for the cooling of metallurgical equipment.

Electrospinning is one of the techniques used to fabricate nanofibers. The syringe pump is one of the main parts of electrospinning, responsible for injecting the solution into the chamber with high precision. The syringe pump has a simple operating system, but it has a high price on the market. Its high price has been one of the obstacles for research groups in the fabrication of nanofibers. Hence, this research aimed to solve the problem of expensive syringe pumps by developing a low-cost syringe pump using affordable components. This research utilized methods from a literature study of syringe pump design, including the manufacturing and assembly of both hardware and software components. It also involved testing the calibration, optimization, and performance of the syringe pumps. An analysis of each stage was carried out until a conclusion was obtained. This syringe pump built in this research used a NEMA 17 stepper motor and TB6600 motor driver to control the flow rate. The total cost to develop this low-cost syringe pump was IDR632,300. Test and calibration were measured at a flow rate ranging from 1 mL/h to 5 mL/h using distilled water, resulting in an accuracy value of 96.7% and a precision value of 95.0%. Further research should utilize gear wheels to reduce the load of the motor stepper so as to prevent prolonged heated conditions. The results of this research can also be used as insight for researchers to develop another low-cost tool in other research fields.

A small leakage in the primary circuit of a nuclear power plant reactor may trigger the occurrence of countercurrent flow which probably develops into a flooding regime followed by the zero penetration caused core cooling failure. During extensive studies in the flooding phenomena in the PWR hot leg, the geometry effects have been widely investigated. The present study investigates the effects of I/D ratios of the riser on the interfacial fluctuations during the counter-current flow on a 1/30 scaled down PWR hot leg geometry. Here, the liquid film fluctuations were acquired by using parallel wire array probes on the basis of a conductance concept. Three I/D ratios which were varied consisted 1.9 (R1), 3.9 (R2) and 8.3 (R3). The obtained data were analyzed on the basis of both time and frequency domains. From the PDF the flooding regime obtains multimodal distributions, while the PSD approaches lower frequencies with higher magnitudes corresponding to either the occurrence of water blockage or slugs. Keywords: I/D ratio, water level fluctuation, counter-current flow, PWR hot leg, parallel wire array probe, stochastic analysis.

Spray technology is an innovative salt production process technology that is able to increase seawater salinity and accelerate the salt production process. This study aims to determine the effect of variations in the amount of spray and discharge in spray technology on increasing seawater salinity. The experimental method was carried out by varying the spray and water discharge amount in spray technology according to the variables. This research has been successfully carried out to increase the salinity of synthetic seawater where to increase from the initial seawater salinity of 2.5 °Be to 24 °Be. It takes 16 hours taken in 3 days using the number of sprays as much as 5 sprays with a seawater flow rate of 0.2424 m³/hour in an evaporation pond of 15í—7 m. The use of the spray method proved effective in accelerating the rate of increase in salinity of synthetic seawater, which was tested to increase the salinity of synthetic seawater from 2.5 °Be to 12 °Be with an evaporation time in traditional methods of 15 days to only 11 hours. This can also happen because the temperature, humidity and wind speed were relatively stable when the research took place.

The working processes and integral characteristics of piston long-stroke low-speed compressor stages are considered. Well-known technologies for increasing the feed rate are considered as objects of comparison: selection of the main dimensions and parameters of the stage; changing the size and design of valves, using elastomeric structural materials; change in the design of the cylinder-piston seal; changing the layout of the suction valve in the working chamber. Indicator efficiency, supply coefficient and tightness coefficient, as well as discharge temperature are considered as integral indicators. The following independent parameters are considered: parameters of the state of the working fluid at suction, discharge pressure, main dimensions and parameters of the stage, distance from the suction valve to the top dead center, seat diameters of the suction and discharge valves, as well as physical and mechanical properties of structural materials. A comparative analysis of the efficiency of the working process of the stage under consideration is carried out using various technologies for reducing the intensity of mass transfer through leaks in the working chamber of a low-speed, long-stroke piston stage. An assessment is made of the achievable value of the feed coefficient with the combined use of various technologies. The features of the working processes of the object under consideration and the relationship between the intensity of mass flows of working gas through leaks in the working chamber of the stage and the technologies used have been studied. The presented results of the theoretical analysis reflect the nature of the change in the integral characteristics of the stage depending on the technologies used to reduce the intensity of mass transfer through leaks in the working chamber of the stage under consideration.

Intake parameters are essential factors that are often overlooked, but can easily change the direct internal reforming solid oxide fuel cell (DIR-SOFC) performance. A three-dimensional model is developed to simulate the effects of intake parameters on the performance of an anode-supported flat-plate DIR-SOFC. The two primary chemical reactions, water gas shift reaction (WGSR) and methane steam reforming reaction (MSR), as well as the electrochemical oxidation of H 2 and CO, are considered in this model. It was found that the aspect ratio corresponding to the peak current density decreases as fuel increases. A moderate air flow rate makes the fuel-to-air ratio (FAR) corresponding to the drastic change in current density relatively small and wide-ranging, resulting in more desirable temperature distribution and fuel utilization. Under the operating conditions of this paper, adjusting the steam-to-carbon ratio (S/C) to between 1.5 and 2 results in both excellent electrical performance and good temperature uniformity. Additionally, adjusting the flow rate by changing the inlet area or velocity has its own advantages in terms of temperature distribution or current density, which must be taken into account when adjusting the flow rate. This study provides a valuable reference on inlet settings of DIR-SOFC, which would help to promote the development of high-performance SOFCs. • A three-dimensional flat-plate DIR-SOFC model has been developed. • Oxidation reaction of CO is included in the mode. • Different flow rates would change the effects of the aspect ratio and S/C. • Impacts of the fuel-air ratio are analyzed fully in terms of both fuel and air sides. • Changing the flow rate by altering the area or speed can make differences. [ABSTRACT FROM AUTHOR]

Thermal storage technology has received increasing attention under the policy of encouraging the development of renewable energy and new clean energy. Optimizing the heat exchange system of phase change thermal storage heat exchangers to obtain better performance has become increasingly urgent. This study comprehensively investigated the actual process of heat transfer and assessed the heat transfer correlation laws between the heat transfer fluids, heat exchange tubes, fins, and phase change materials. Taking the heat exchange efficiency of the heat exchanger as a guide, a simulation was conducted on the effect of the presence and quantity of fins as well as the flow rate of the cooling liquid on the heat exchange efficiency of the heat exchanger. The simulation results showed that too many or too few fins were not conducive to improving heat transfer efficiency. In addition, no positive correlation was observed between the flow rate of the cooling liquid in the heat exchanger and the heat transfer efficiency of the heat exchanger. Specifically, models with slightly slower cooling liquid flow rates had a higher heat transfer efficiency. After a sensitivity analysis, it was found that the number of fins had a more significant effect on the heat transfer efficiency of the heat exchanger than the flow rate of the cooling liquid. The heat exchanger with five fins and a cooling liquid flow rate of 0.1 m/s demonstrated the best heat transfer effect, achieving a temperature drop of 14.76% within 5 min. [ABSTRACT FROM AUTHOR]

Bacterial respiratory tract infections (e.g., in patients with cystic fibrosis) may be treated with the intravenous infusion of a piperacillin/tazobactam (P/T) solution through an elastomeric device. In the present work, we combined a 24-h drug stability study with an assessment of the drug solution flow rate during an in vitro simulated infusion. Experiments were performed in triplicate with two excipient-free generic P/T solutions and an excipient-containing proprietary P/T solution in saline (all 50/6.25 mg/mL) released from an elastomeric infusion device at 32 °C. The P/T solutions' stability was assessed by an HPLC-UV assay, pH and osmolality measurements, a visual assessment, and particle counting. Before these analyses, a forced degradation study was performed. To assess the flow rate, a precision scale was used to weigh the solution collected at the infusion line outlet. The stability criteria were <10% degradation and a flow rate within ± 15% of the nominal value over the 24-h infusion period: all three P/T solutions were found to be stable. The actual flow rate was lower than the expected flow rate; this difference was probably due to the drug solution's high viscosity and must be taken into account in clinical use. [ABSTRACT FROM AUTHOR]

This study presents findings related to the characterization of cubic SnS (π-SnS) thin films and p-SnS/n-Si heterojunction structures produced simultaneously using the ultrasonic spray pyrolysis technique. In this context, the impact of different spray solution flow rates on the morphological, structural, optical, and electrical characteristics of the films was examined. Morphological analyses revealed that higher flow rates resulted in films with denser and smoother surfaces, approximately 6 nm in roughness. Additionally, it was observed that both the thickness and the growth rate of the films could be adjusted through the modulation of the flow rate. Structural analyses determined that the crystallite size increased and micro-strain values decreased with increasing flow rates. Optical evaluations indicated a decline in the optical band gap of the thin films from about 1.8 eV to 1.7 eV as the flow rates increased. This trend was consistently observed in the data obtained using the Tauc method and the derivative of transmission with respect to wavelength versus photon energy graphs. Electrical analyses revealed that the resistivity values of the thin films increased from 5.24 × 105 Ωcm to 1.64 × 106 Ωcm with increasing flow rates. Furthermore, I-V analyses of the Au/p-SnS/n-Si/Ag heterojunction structures indicated significant variability in key electrical properties. The saturation currents displayed a broad range, suggesting varying efficiencies in charge carrier collection across different samples. Similarly, the change of ideality factors pointed to differences in charge transport mechanisms, while the shifts in barrier heights indicated changes in junction properties with different fabrication conditions. The results of this study offer valuable perspectives for future research. [ABSTRACT FROM AUTHOR]

Purpose: In patients with a need for frequent but intermittent apheresis, vascular access can prove challenging. We describe the migration of the use of a Vortex LP dual lumen port (Angiodynamics, Latham, NY) to one Powerflow and one ClearVUE power injectable port (Becton Dickinson, Franklin Lakes, NJ) in a series of patients undergoing intermittent apheresis. Materials and Methods: All patients had a need for long‐term intermittent apheresis. Eight had double lumen Vortex port (pre) and were exchanged for one Powerflow port and one conventional subcutaneous venous port with 90° needle entry (post) while 12 did not have any port in place and received the same configuration. IRB approval was granted. We recorded the treatment time, flow rate, and tissue plasminogen activator (tPA) use for five treatment sessions after placement. When available, we compared five treatments with the Vortex port and the new configuration. Results: The mean treatment time is reduced with the new configuration (P = 0.0033). The predicted mean treatment time, adjusting for gender, race, BMI and age and accounting for correlations within a patient is 91.18 min pre and 77.96 min post. The flow rate is higher with the new configuration (P < 0.0001). The predicted mean flow rate in mL/min is 61.59 for the Vortex port and 71.89 for the new configuration. tPA use was eliminated in the population converted from Vortex ports and had a 48% reduction when compared to all other configurations in the study. Conclusion: The introduction of a novel device configuration of venous access ports for intermittent apheresis resulted in higher flow rates and less total time for treatment. Use of tPA was greatly reduced. These results suggest that the new configuration could result in less expense for the hospital and better throughput in a busy pheresis practice. Clinical trial registration with ClinicalTrials.gov: NCT04846374. [ABSTRACT FROM AUTHOR]

To investigate the hydraulic effects and performance of the micro-pressure filtration and cleaning tank under conditions with sandy and brackish water, physical model tests were conducted with five groups of flow rates (6–14 m³ h−1), four groups of sediment contents (0.5–2.0 g l−1), five groups of mineralisation degrees (0–5.0 g l−1), and three groups of screen apertures (0.125, 0.150, and 0.180 mm). Dimensional analysis, multiple linear regression analysis, and the non-dominated sorting genetic algorithm II (NSGA-II) were used to analyse the test results. The results showed that the optimal operating conditions of the micro-pressure filtration and cleaning tank under the scope of this test were a screen aperture of 0.175 mm, a flow rate of 13 m3 h−1, a sediment content of 1.8 g l−1, and a mineralisation degree of 4.7 g l−1. The micro-pressure filtration and cleaning tank was intermittently discharged and rinsed, the discharge time was 30–40 s, and the flow rate of discharge and rinsing was 5.54 m3 h−1. Prediction models of the head loss and the filtration efficiency of the filter were established. The coefficients of determination (R2) were greater than 0.9, the average relative errors of the predicted and measured values were 2.98% and 2.17%, respectively, and the corresponding root mean square errors were 0.0549 m and 0.642. The research results can be used as a reference for in-depth investigations on the performance of the micro-pressure filtration equipment in front of pumps. • Head loss and filtration efficiency models of pre-pump filters were established. • Optimal working condition of the filter was obtained using NSGA-II. • Optimal discharge time and discharge flow rate were determined. [ABSTRACT FROM AUTHOR]

The recirculating system for tilapia aquaculture is an intensive system with very high stocking densities, thus requiring prime water quality and optimal flow rates. The research aims to determine the influence of different interactions between flow rates and stocking densities on the growth and survival of tilapia (Oreochromis niloticus) in a recirculating system. The research design employs a Complete Randomized Factorial Design (CRFD) with two factors: Flow Rate (D) with two levels, namely D1 = 0.25 liters/second and D 2 = 0.50 liters/second, and Stocking Density (P) with two levels, namely P1 = 100 fish/m3 and P2 = 150 fish/m3. The results indicate that the flow rate factor (D) has no significant effect, while the stocking density factor (P) has a significant effect, and there is no interaction between the factors. The treatment D1P1 (0.25 liters/second and 100 fish/m3) is the optimal treatment, with a survival rate of 99.1%, relative weight gain of 784.56%, and feed conversion ratio of 1.34. [ABSTRACT FROM AUTHOR]

Methane is a powerful greenhouse gas with a global warming potential 34 times greater than carbon dioxide. The emitter flow rate, as a fundamental parameter of drip irrigation systems, controls the horizontal and vertical distribution of soil water, resulting in distinct soil wetting patterns. At the same time, the soil wetting pattern influences soil temperature, aeration, and the movement and transformation of nitrogen, all of which affect soil microbial activity and consequently methane uptake. Understanding the role of the emitter flow rate of drip irrigation in regulating the diffusion, oxidation and surface uptake of methane in the soil is crucial to increasing the potential of methane uptake in drip-irrigated croplands to mitigate global climate change. In this study, a two-year field experiment combining static chamber gas chromatography with the concentration gradient method was conducted in 2021 and 2022 in Wuwei, Gansu of China. Three drip irrigation flow rates (F1: 1.3 L/h, F2: 2.0 L/h, F3: 3.0 L/h) were set to investigate the characteristics of methane diffusion, absorption, and surface net uptake in different soil layers and their responses to soil environmental factors. The results showed that soil methane concentrations decreased with increasing soil depth. There was no significant difference in the average surface methane concentration between treatments, and the average methane concentration in the 0-60 cm soil layer showed F3 > F2 > F1. The value in the F3 treatment was significantly higher than F1 by 11.9% in the 0-20 cm soil layer. The average methane concentration of F3 treatment was significantly higher than that of F2 and F1 treatments by 8.5%, 26.8% (>20-40 cm soil layer) and 10.2%, 19.1% (>40-60 cm soil layer), respectively. Average surface methane uptake fluxes were 85.4, 80.2 and 78.5 μg g/(m−2 h) for F1, F2 and F3 treatments, respectively, and were significantly increased by 6.4% and 8.9% for F1 treatment compared to F2 and F3 treatments (P < 0.05). The average methane diffusion flux in the 0-20 cm and >20-40 cm soil layers was significantly higher in the F1 treatment than in the F2 and F3 treatments, while the average methane diffusion flux in the 40-60 cm soil layer was significantly lower in the F1 treatment than in the F2 and F3 treatments. The cumulative methane uptake in the F1 treatment increased by 5.9%-13.8% compared to the F2 and F3 treatments, respectively. Methane uptake primarily occurred in the 0-20 cm soil layer, accounting for 72.1%-82.5% of the total uptake. Emitter flow rate had significant effects on soil water-filled pore space, soil oxygen concentration and nitrogen content (P < 0.05). Among various soil environmental factors, soil water-filled pore space had the most significant influence on soil methane concentration. Cumulative surface methane uptake fluxes were significantly and positively correlated with cumulative methane diffusion fluxes (downward) in the 0-20 and >20-40 cm soil layers, and cumulative methane diffusion fluxes in the >20-40 cm soil layer were significantly positively correlated with the values in the 0-20 cm soil layer. Cumulative methane transformation fluxes in the 0-20 cm soil layer were significantly and positively correlated with cumulative methane diffusion fluxes in the 0-20 cm soil layer, and cumulative transformation fluxes in the >20-40 cm soil layer were significantly and positively correlated with cumulative diffusion fluxes in the 0-20 and >20- 40 cm soil layers. The lower values of soil water-filled pore space in the surface soil of the F1 treatment facilitated the entry of methane from the atmosphere into the soil and its diffusion into deeper layers, thereby increasing methane uptake. In addition, the potato yield and irrigation water use efficiency under F1 treatment were relatively highest. Soil methane uptake, diffusion, and transformation were influenced by soil water distribution. Therefore, it should be considered to regulate the soil wetting area through an appropriate emitter flow rate to enhance the soil methane sink capacity and potato yield in the drip irrigation management. The results can provide a valuable information for soil carbon sinks and potato yield improvement in drip irrigated soils. [ABSTRACT FROM AUTHOR]

The high- and low-pressure switching of the axial piston pump is realized by the structure of the valve plate, and the buffer-groove structure on the valve plate is very important to reduce the pressure shock and flow fluctuation. In order to optimize the structural parameters of the buffer tank of the piston pump, the influence of the triangular-groove structure on the outlet pressure–flow characteristics was analyzed, and the low-pulsation buffer-groove structure was designed. First, the relationship between the structure of the triangular buffer tank and the output pressure and flow characteristics of the pump was analyzed theoretically. The Computational Fluid Dynamics (CFD) method was used to calculate the pressure and flow characteristics of the whole pump flow field of the triangular-groove structure, and the influence of the buffer-groove structure parameters on the outlet flow pulsation characteristics was studied. The multi-objective optimization algorithm was used to optimize the structure parameters of the buffer tank, and the optimized structure significantly reduced the outlet pressure–flow pulsation of the piston pump. The results show that, after optimization, the width angle of the front and rear triangular groove is 82.3°, the depth angle is 12.7°, the optimized pressure pulsation rate is 0.3%, and the optimized flow pulsation rate is 13.7%. [ABSTRACT FROM AUTHOR]

TPP-9 of PJSC "Mosenergo" is equipped with an AE64.3A gas turbine (manufactured by Ansaldo Energia) delivering flue gases to a Pr-94-13.8-545 single pressure vertical heat recovery steam generator (P-111, manufactured by JSC "ZiO-Podolsk") used for generating superheated steam as well as providing heat for district heating. The generated steam enters the TPP-9 common steam header with the designed pressure of 13.8 MPa and is further used for driving steam turbines. The common steam header is also fed by conventional steam boilers located at TPP-9. Under the current scheme, the gas turbine unit (GTU) and HRSG operation is only possible in conjunction with conventional steam boilers and, therefore, separate operation of GTU, HRSG with any of steam turbines as a power unit is impossible. The requirement for joint operation of GTU, HRSG, and conventional boilers imposes significant restrictions on operating equipment as well as the load range of TPP-9 and causes low GTU, HRSG annual operating time primarily occurring during the fall-winter period. The latter is further worsened by the fact that GTU, HRSG operation is mostly appropriate during the spring-summer period providing compensation for the TPP efficiency decrease caused by a low heat output. An increase in GTU, HRSG annual operating time is possible after retrofitting the current TPP-9 thermal scheme allowing operation of GT, HRSG as a power unit with an existing or newly installed steam turbine, which will simultaneously provide an increase in TPP-9 technical and economic indicators as well as equipment readiness and maneuverability. This will provide the opportunity to optimize operation according to the current loads schedule while maintaining the reliable power and heat output. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of parameters associated with minimum quantity lubrication (MQL) in CNC turning of DIN 1.2738 plastic mold steel. The independent parameters considered include flow rate ( F r ), nozzle distance ( N d ), and nozzle angle ( N a ), with the objective of ensuring effective lubrication. The study focuses on evaluating surface roughness, cutting temperature, and specific cutting energy (SCE) to assess machinability. Experiments were conducted using coated carbide inserts SNMG 120,412-km and a commercially available vegetable oil-based cutting fluid, Eraoil KT/2000. Constant cutting parameters, such as cutting speed (220 m/min), feed rate (0.05 mm/rev), depth of cut (0.5 mm), nose radius (1.2 mm), working pressure (0.5 MPa), and nozzle radius (1 mm), were maintained. The methodology employed various analytical approaches, including analysis of variance (ANOVA), response surface methodology (RSM), gray relational analysis (GRA), and desirability function (DF). The results indicate that the MQL system effectively provided lubrication over a short nozzle distance of 10 mm by employing a high flow rate of 51 ml/h and a significant nozzle angle of 60°. These conditions resulted in satisfactory performance for machinability-related parameters. Consequently, surface roughness ( R a ) remained between 0.15 and 0.18 μm, cutting temperature ( T c ) ranged from 130 to 135 °C, and SCE consumption ( E cs ) was reduced to 3.37 J/mm3. [ABSTRACT FROM AUTHOR]

Introduction: Saliva plays a critical role in preventing dental caries through regulation of pH, flow rate and proteins of saliva. Tea leaves from black tea (Camellia sinensis) is one of the plants containing catechins that has shown to influence secretion of saliva, thus it can inhibit the development of caries. This study aimed to investigate the effect of consuming black tea (Camellia sinensis) on level of salivary pH, flow rate and secreted lysozyme in caries and caries-free subjects. Materials and methods: Saliva was obtained from twenty four participants divided into two categories, caries and caries free group. Subjects were asked to collect saliva before and 30 minutes after drinking a cup of tea. Salivary pH was measured using a digital pH meter, while the flow rate was measured by weighing the collected saliva divided by time. The concentration of lysozyme was assessed by using ELISA kit. The data were analyzed using paired t-test and Mann Whitney test. Results: The results showed that black tea significantly increased pH and salivary flow rate, but had no significant effect on salivary lysozyme. It also demonstrated that there was no significant difference on salivary pH, flow rate, lysozyme after drinking black tea in the caries subjects compared to the caries free. Conclusion: Although drinking black tea could raise salivary pH and flow rate, but it did not promote the increase of lysozyme. This finding suggests that black tea had no unfavourable impact on saliva in oral environment. [ABSTRACT FROM AUTHOR]

In this paper, a 3-D geomechanically model and a three-pressure profile along the wellbore trajectory were established to determine a reasonable drilling mud density window by establishing calculation methods and correlations between geomechanically parameters. On the basis of drilling mud density window, combined with the principle of ERW extended limit, the analysis models of the limits of density and flow rate of drilling mud were established, respectively, with the objective that the extension limit can fulfill the design depth of the wellbore. The results of the practical application illustrate the feasibility and correctness of this preferred model for the combination of drilling mud density and flow rate. [ABSTRACT FROM AUTHOR]

Organ-on-a-chip technologies show exponential growth driven by the need to reduce the number of experimental animals and develop physiologically relevant human models for testing drugs. In vitro, microfluidic devices should be carefully designed and fabricated to provide reliable tools for modeling physiological or pathological conditions and assessing, for example, drug delivery through biological barriers. The aim of the current study was to optimize the utilization of three existing skin-on-a-chip microfluidic diffusion chambers with various designs. For this, different perfusion flow rates were compared using cellulose acetate membrane, polyester membrane, excised rat skin, and acellular alginate scaffold in the chips. These diffusion platforms were integrated into a single-channel microfluidic diffusion chamber, a multi-channel chamber, and the LiveBox2 system. The experimental results revealed that the 40 µL/min flow rate resulted in the highest diffusion of the hydrophilic model formulation (2% caffeine cream) in each system. The single-channel setup was used for further analysis by computational fluid dynamics simulation. The visualization of shear stress and fluid velocity within the microchannel and the presentation of caffeine progression with the perfusion fluid were consistent with the measured data. These findings contribute to the development and effective application of microfluidic systems for penetration testing. [ABSTRACT FROM AUTHOR]

The article compares the efficiency of technologies for feeding liquid metal into the mold of a continuous casting machine (CCM) and its flow within the mold volume under conditions of free and forced mixing. The influence of various designs of the developed mixing devices on the nature of the melt flow in the mold volume is analyzed. The objects of research are the hydrodynamic and thermal flows of liquid metal during the casting of steel into the CCM mold. [ABSTRACT FROM AUTHOR]

The proper utilisation of the coating fluid is crucial for ensuring the effectiveness of the wire coating process. Its complexity and importance make it the central focus of the present study. Also, understanding wire coating processes is important for ensuring product performance, cost efficiency, regulatory compliance, customer satisfaction, innovation and environmental sustainability. By optimising the coating processes, manufacturers can produce high-quality wire products that meet market demands while minimising negative impacts on the environment and resources. The objective is to assess the quality and performance of the wire coating process by examining the fluid flow characteristics within the die. Therefore, a mathematical model is devised to study the rheological properties of Sisko fluid with a constant pressure gradient in an unsteady state. The governing equation with oscillating boundary constraints is converted into dimensionless form and solved numerically using the method of lines (MoL) technique. The findings are presented through 2D and 3D plots. Response surface methodology (RSM) is implemented to investigate the statistical significance and sensitivity of the parameters and to optimise the shear stress rate. [ABSTRACT FROM AUTHOR]

Polymer electrolyte membrane fuel cells (PEMFCs) have attracted much attention as highly efficient, eco-friendly energy conversion devices. However, carbon-supported Pt (Pt/C) catalysts for PEMFCs still have several problems, such as low long-term stability, to be widely commercialized in fuel cell applications. To address the stability issues of Pt/C such as the dissolution, detachment, and agglomeration of Pt nanoparticles under harsh operating conditions, we design an interesting fabrication process to produce a highly active and durable Pt catalyst by introducing a robust carbon shell on the Pt surface. Furthermore, this approach provides insights into how to regulate the carbon shell layer for fuel cell applications. Through the application of an appropriate amount of H2 gas during heat treatment, the carbon shell pores, which are integral to the structure, can be systematically modulated to facilitate oxygen adsorption for the oxygen reduction reaction. Simultaneously, the carbon shell functions as a protective barrier, preventing catalyst degradation. In this regard, we investigate an in-depth analysis of the effects of critical parameters including H2 content and the flow rate of H2/N2 mixed gas during heat treatment to prepare better catalysts. [ABSTRACT FROM AUTHOR]

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As green infrastructure has evolved, grass swales have become integral components of stormwater management. Manning's equation is commonly used to describe the hydraulic characteristics of grass swales. However, due to flow loss from infiltration, grass swales often deviate from the assumptions of Manning's equation, potentially leading to significant errors in grass swale flow rate calculations. In this study, we systematically investigated changes in flow rates in grass swales under various constant inflow rate conditions. The results indicated that the suitability of using Manning's equation to estimate flow rate in grass swales varies with inflow rate. At an inflow rate of 3.00 m3/h, the discrepancy between the measured and the estimated flow rates by Manning's equation was the smallest, ranging from −0.24 to 0.19 m3/h. At lower inflow rates (1.00 to 2.00 m3/h), Manning's equation underestimated the flow rates by 0.16 to 0.47 m3/h; at higher rates (4.00 m3/h), it overestimated the flow rates by 0.01 to 0.61 m3/h. Considering infiltration losses as the primary cause of these errors, we proposed an improved Darcy's formula for estimating the infiltration rates in grass swales, along with a modified Manning's equation for more accurate flow rate calculations. The modified Manning's equation provides enhanced accuracy in calculating flow rates in grass swales compared to the traditional version. [ABSTRACT FROM AUTHOR]

Due to the depletion of traditional fossil fuels and the aggravation of related environmental problems, hydrogen energy is gaining more attention all over the world. Solid oxide fuel cell (SOFC) is a promising power generation technology operating on hydrogen with a high efficiency. To further boost the power output of a single cell and thus a single stack, increasing the cell area is an effective route. However, it was recently found that further increasing the effective area of an SOFC single cell with a flat-tubular structure and symmetric double-sided cathodes would result in a lower areal performance. In this work, a multi-physical model is built to study the effect of the effective area on the cell performance. The distribution of different physical fields is systematically analyzed. Optimization of the cell performance is also pursued by systematically tuning the cell operating condition and the current collection setup. An improvement of 42% is revealed by modifying the inlet gas flow rates and by enhancing the current collection. In the future, optimization of cell geometry will be performed to improve the homogeneity of different physical fields and thus to improve the stability of the cell. [ABSTRACT FROM AUTHOR]

Spray technology is an innovative salt production process technology that is able to increase seawater salinity and accelerate the salt production process. This study aims to determine the effect of variations in the amount of spray and discharge in spray technology on increasing seawater salinity. The experimental method was carried out by varying the spray and water discharge amount in spray technology according to the variables. This research has been successfully carried out to increase the salinity of synthetic seawater where to increase from the initial seawater salinity of 2.5°Be to 24°Be. It takes 16 hours taken in 3 days using the number of sprays as much as 5 sprays with a seawater flow rate of 0.2424 m³/hour in an evaporation pond of 15×7 m. The use of the spray method proved effective in accelerating the rate of increase in salinity of synthetic seawater, which was tested to increase the salinity of synthetic seawater from 2.5 °Be to 12 °Be with an evaporation time in traditional methods of 15 days to only 11 hours. This can also happen because the temperature, humidity and wind speed were relatively stable when the research took place. [ABSTRACT FROM AUTHOR]