Tube Type Research Articles

Measurement of the Photoelectron Yield from the Synchrotron Radiation for the NEG-coated Tubes

NEG-coated chambers have been adopted as the beam ducts for large particle accelerators and synchrotron light sources for the sake of the lower yields of the photon stimulated desorption (PSD) and the photoelectrons (PE) from the NEG films in addition to their pumping performance. Measurement of the photoelectron yield (PEY) was performed at the BL19B (PSD) beamline of the 1.5 GeV Taiwan Light Source (TLS) which simultaneously measures the PSD-yield. An aluminium cathode was inserted in the tubes and a positive bias of voltage for extraction of the photoelectrons applied. The PEY was obtained by dividing the photoelectron current by the photon flux of the synchrotron radiation. Measurements of the PEY include various types of NEG-coated stainless steel tubes and the bare tubes of titanium and aluminium alloys for the comparison. The experimental system and the results will be described in this presentation.

Effect of Concave Corrugated Tube Shape on The Effectiveness of Double Pipe Heat Exchanger

Heat exchangers have an important role in everyday life. A heat exchanger is a device used as a means of energy transformation. The development of heat exchangers undergoes a form transformation that aims to increase efficiency through its work function. Double-pipe heat exchanger with a corrugated tube type is a simple and often applied method used in heat transfer. The use of a concave shape on the corrugated tube aims to increase the convection heat transfer area. The purpose of this research is to determine the effect of using concave shapes on corrugated tubes on the effectiveness of double-pipe heat exchangers. The object of this research is a double pipe heat exchanger with a concave corrugated tube and then varied with triangular, trapezoidal, and square concave shapes. Data collection of experimental results on double pipe heat exchanger using pressure gauge, flowmeter, and thermocontrol as research instruments. The research data were analyzed descriptively calculated theoretically and then converted into graphs and tables. The results achieved to date are the addition of concave shape variations on corrugate tubes can increase the value of thermal conductivity and other characteristics, in the form of a concave triangle with the effectiveness value increased by 11,63%.

Ahmed ClearPath vs. Baerveldt Glaucoma Implant: A Retrospective Noninferiority Comparative Study

To compare the efficacy and safety of two non-valved glaucoma drainage devices (GDDs): Ahmed ClearPath (ACP) vs. Baerveldt glaucoma implant (BGI). Single-center, retrospective, comparative study. Consecutive patients who underwent ACP or BGI surgery for glaucoma (250 mm2 or 350 mm2 models), and had ≥6 months of follow-up and no prior GDD implantation. Chart review of ACP or BGI surgery in patients with glaucoma at Wills Eye Hospital (2020-2023). The primary outcome measure was surgical failure at the end of follow-up, defined as intraocular pressure (IOP) >21 or <6 mmHg at 2 consecutive visits, progression to no light perception (NLP) vision, glaucoma reoperation, or implant removal. Secondary outcome measures included the rate of postoperative complications and changes in best corrected visual acuity (BCVA), IOP, and glaucoma medications. A total of 128 eyes of 113 patients (63 ACP, 65 BGI) with similar baseline characteristics and a mean follow-up duration of 19.6±10.8 (median 20.5) months were included. Surgical failure occurred in 12 eyes (9.4%) with no significant difference between ACP and BGI eyes (9.5% vs. 9.2%, respectively; P=0.810). Reasons for failure included IOP >21 mmHg (3/12, 25.0%), glaucoma reoperation (5/12, 41.7%), and tube removal (4/12, 33.3%). No eyes progressed to NLP vision. Kaplan-Meier survival analysis showed similar cumulative rate of surgical failure in both groups (P=0.871). Both groups achieved significant IOP and medication reduction compared to their baseline. Final IOP, BCVA, and complication rate was similar in both groups, but medication number was significantly lower in the ACP group (P=0.012). Both the 250 mm2 and 350 mm2 models had similar outcomes, but diplopia was significantly associated with the 350 mm2 model of either implant (P=0.012). Univariate logistic regression analysis did not identify either tube type or plate size as predictors of surgical failure. To our knowledge, this is the first study to compare the recently approved ACP vs. the BGI. Both implants had similar surgical failure and complication rate. Final IOP was similar in both groups, but ACP achieved lower medication number. Diplopia was significantly associated with the use of 350 mm2 model of either implant. Neither tube type nor plate size were significant predictors of surgical failure.

Impact of thermal desorption tubes on the variability of exhaled breath data

Due to the overall low abundance of volatile compounds in exhaled breath, it is necessary to preconcentrate the sample prior to traditional thermal desorption (TD) gas chromatography mass spectrometry analysis. While certain aspects of TD tubes, such as volatile storage, have been evaluated, many aspects remain uncharacterized. Two common TD tubes, Tenax TA and Biomonitoring 5TD tubes, were evaluated for background content and flow rate variability. The data illustrate that the Biomonitoring 5TD tubes have the highest number (23) and abundance of background contamination greater than 3x the mean noise when compared to Tenax TA (13) and empty tubes (9). Tentative identifications of the compounds in the background contamination experiment show that greater than 59% (16/27) of the compounds identified have been reported in the breath literature. The data illustrate the TD tube background abundance could account for more than 70% of the chromatographic signal from exhaled breath for these select compounds. Flow rate measurements of 200 Tenax TA and 200 Biomonitoring 5TD tubes show a large range in measured flow rates among the TD tubes (Tenax: 252.9–284.0 ml min−1, 5TD: 220.6–255.1 ml min−1). Finally, TD tubes of each type, Tenax TA and Biomonitoring 5TD, previously established to have high, medium, and low flow rates, show insignificant differences (p > 0.05) among the tubes of different flow rates, using both gas standards and an exhaled breath from a peppermint experiment. Collectively, these results establish overall background compounds attributed to each TD tube type tested. Additionally, while measured flow rate variability is present and plausibly impacts exhaled breath results, the data demonstrate no statistically significant difference was observed between tubes showing high, medium, and low flow rates from two separate sample types.

Mechanical properties of seawater volcanic scoria aggregate concrete-filled circular GFRP and stainless steel tubes under axial compression

Abstract In this study, the properties of seawater volcanic scoria aggregate concrete (SVAC)-filled circular stainless steel (SFCST) and glass fibre-reinforced plastic (GFRP) tubes (SFCGT) were investigated. Ten groups were considered and 30 specimens were prepared, including four different parameters: the concrete type (SVAC and ordinary concrete [OC]), outer tube type (GFRP and stainless steel tubes), concrete strength (C30 and C40), and tube thickness (0, 3, and 4 mm). The typical influences of the SVAC and outer tube on the mechanical properties of specimens were then analysed. The research findings show that the strength and ductility of the SFCGT and SFCST are significantly higher than those of plain SVAC. The peak strain and strength enhancement factor of the SFCGT and SFCST increase with an increase in the tube thickness, and the concrete strength has a detrimental impact on the toughness of the specimen. Unlike in the confined OC specimens, a sudden decrease is observed in the stress–strain curves of the SFCGT and SFCST owing to the changes in the deformability of the SVAC. Generally, the strengths of the SFCGT and SFCST specimens are 10.3% lower and 4.1% higher than those of the confined OC specimens, respectively. Finally, analytical models of the strength and stress–strain curves considering the influences of the SVAC and passive confinement were established, and numerical simulations were performed to provide a basis for the practical application of the SFCGT and SFCST.

Heat transfer enhancement of supercritical carbon dioxide in eccentrical helical tubes

A type of eccentrical helical tube (EHT) was proposed for more efficient and compact supercritical carbon dioxide (SCO2) heat exchangers in refrigeration systems. The forced convective heat transfer of SCO2 flowing in three designed eccentrical helical tubes with pitches of 25, 50 mm and eccentricities of 0.9, 1.5 mm was simulated by using the three-dimensional steady Reynolds-averaged Navier-Stokes equations, shear stress transport turbulence model and energy equation in ANSYS CFX 2019 R2 at mass fluxes of 200, 400 kg/m2s, inlet pressures of 8, 9 MPa, outwards wall heat fluxes of 12, 24 kW/m2. The flow and heat transfer models were validated in the plain tube with experimental mean heat transfer coefficient and empirical Darcy friction factor. Influences of pitch, eccentricity and operational conditions on heat transfer enhancement were identified. Flow pattern, heat transfer mechanism and vortex kinematics were clarified. Heat transfer enhancement of SCO2 in the EHT was compared with water and air in the EHT, twisted elliptical tube and conical tube, respectively. A pitch of 25 mm and eccentricity of 1.5 mm at 6 mm tube diameter can achieve a better thermal-hydraulic performance. A higher SCO2 mass flux raises Nusselt number and reduces friction factor, a higher inlet pressure and a larger wall heat flux reduces Nusselt number but increases friction factor. The ratio f/f0 is ranged in 2.52–1.68 and drops off with increasing inlet pressure and nominal Reynolds number, the ratios Nu/Nu0, ψ and η curves show a concave shape near the pseudocritical point ranged in 1.68–1.06 and 1.06–1.55, 1.23–0.83 and 0.83–1.30, 0.67–0.50 and 0.50–0.92 at the pitch of 25 mm and eccentricity of 1.5 mm, inlet pressure of 8 MPa, mass flux of 400 kg/m2s, and wall heat flux of 12 kW/m2. A helical flow pattern with a core flow occurs in the EHT, the local heat transfer coefficient can be correlated to absolute helicity. The high-wall shear stress on the ridge of the EHT is responsible for the heat transfer enhancement. The f/f0 value of the EHT is in between the twisted elliptical tube and the conical tube, but the Nu/Nu0 and ψ values are comparable.

Experimental study on the external resistance of vertical tube indirect evaporative coolers

To address the calculating difficulty of external resistance of vertical tube in the widely used indirect evaporative coolers, this paper experimentally investigates the influencing factors of the tube external resistance and develops calculation formula for tube external resistance. An experimental setup was constructed to test the external resistance of different numbers of tube rows at wind speeds of 1 m/s, 1.5 m/s, 2 m/s, 2.5 m/s, and 3 m/s. A specific vertical tube indirect evaporative cooler with a tube diameter of 25 mm, tube-to-tube center distance of 35 mm, and row-to-row center distance of 30 mm was studied. It was found that the tube external resistance of the studied cases is mainly affected by the face wind speed and the number of tube rows. Based on the response surface method (RSM), a formula for calculating the tube external resistance was fitted using the measured data, which provides guidance for engineering applications of vertical tube type indirect evaporative coolers.

Investigation of Alpha Detection Performances of Two Different Types of Photomultiplier Tubes

Investigation of Alpha Detection Performances of Two Different Types of Photomultiplier Tubes

The effect of alphabet-shaped twisted tape on thermo-fluidic properties in a shell-tube type heat exchanger: A comparative study utilizing a two-phase mixture model

In the present Computational Fluid Dynamic (CFD) simulation, the impact of various shapes of alphabet twisted tape in a shell –tube type of heat exchanger on the pressure drop, temperature, velocity distribution, and heat transfer coefficient was studied numerically. The best shape of the twisted tape was selected by thermo-hydraulic analysis. SIMPLE algorithm and Finite Volume Method (FVM) were then implemented to solve the conversion formulas. Conversion equations were discretized using second-order upwind discretization. Comparing the results of different types of twisted tape, Case I (W-shaped tape) exhibited the best performance and the utmost pressure differences. Furthermore, the utmost heat transfer factor was obtained by W shape twisted tape. Also, the helical baffles illustrated the best performance of the shell-part baffles in the shell-tube type of heat exchanger. Comparison between single and two-phase flow by utilizing mixture model for heat transfer factor and pressure difference reveal the negligible changes. On the quant part, FOM amount have been shown a great significance (1.3439) in the shell part for helical baffle type.

Effect of Small Concaves Surface on the Acoustical Characteristics of Chicken Feather Panel

This study aims to determine the impact of small concave surfaces on the acoustic characteristics of chicken feather panels. Based on the feather-glue ratio reference, the researchers applied a mixture of 70% feather and 30% PVAc for the production of the specimens. In the first stage, the absorption coefficient of the specimen on a small concave surface (CS) was measured using an impedance tube type B&amp;K 4602 with two microphones and a set of computer FFT analyzers. The measurement results were then compared with the absorption coefficient of similar test objects with flat surfaces (FS). The acoustic characteristics of the two types of surfaces (FS and CS) in the specimen panel showed the maximum absorption coefficient (α) value of 0.52 and 0.63 for FS and CS, respectively. These results indicate that specimens with a small concave surface (CS) have a relatively higher absorption coefficient than those with a flat surface (FS). However, further studies are needed to identify other characteristics of these acoustic panels, including their resistance to environmental influences.

Optimization of gaseous working fluid and internally finned absorber tube for enhancing the thermal performance of parabolic trough solar collector

The current study examined the effect of various types of longitudinal finned absorber tubes with the gaseous working fluid on the performance of the parabolic trough collector. Conventional heat transfer fluids, such as water, thermal oils, molten salts, etc., have been limited when the parabolic trough collector works at very high temperatures. Gas may be used as heat transfer fluid when this collector may operate at very high temperatures. However, the heat transfer coefficient of gas is smaller than the conventional heat transfer fluid. Therefore, fins may be used to improve the parabolic trough collector's thermal performance when gas is used as heat transfer fluid. Hence, selecting the best suitable gas as heat transfer fluid and the optimum fin structure is essential to improve this collector's thermal performance. In this context, the current study has considered seven different gases, namely air, carbon dioxide, helium, nitrogen, oxygen, methane, and neon, and six longitudinal finned absorber tubes with different profiles, namely, rectangular, triangular, trapezoidal, T-shaped, and Y-shaped to select the best suitable heat transfer fluid and optimum fin structure. The best suitable gas and optimum fin profile have been chosen based on specific criteria (multi-objective optimization technique or the performance enhancement factor index). This problem has been simulated using commercial software ANSYS Fluent 2020 R2. The experimental and numerical data discovered in the literature are used to validate the results of the current investigation and found in good accuracy between them. The methane gas is found to be the most suitable heat transfer fluid based on both criteria. Then, the effect of mass flow rate and inlet temperature of methane gas on the average friction factor and Nusselt number have been investigated. It is found that the average friction factor decreases with the mass flow rate for the given inlet temperature, while the opposite trend has been observed for the average Nusselt number. For the first time, the T-shaped and Y-shaped finned absorber tube has been proposed in the present study and compared with earlier fin profiles utilized by the researcher. It is found that the increment in thermal efficiency for T-shaped and Y-shaped finned absorber tubes with methane gas is 8.9338 % and 10.1360 %, respectively. In contrast, the increment in exergy efficiency for T-shaped and Y-shaped finned absorber tubes is 8.942 % and 11.622 %, respectively. There is a significant improvement in the thermal and exergy efficiency of the proposed model compared to the models considered in the literature (air flow through absorber tube with the rectangular fin profile). Furthermore, the highest average Nusselt number of 480.4651 is found for the T-shaped finned absorber tube than other examined cases. However, the friction factor is also high for these fin profiles. As a result, the value of the performance enhancement factor for this fin profile is reduced, and the maximum value of the performance enhancement factor is obtained for rectangular fin profiles. Generally, increasing fin height and width increases thermal performance and pressure loss. Therefore, six different dimensions of rectangular fin have been studied and compared with smooth tubes. It is found that the optimum fin dimension of the rectangular fin is a height of 5 mm and a width of 4 mm. The present results can be utilized for designing an internally finned absorber tube to improve the collector's thermal performance with gas as heat transfer fluid.

Variation in properties of double-walled zigzag and armchair silicon nanotubes depending on SW defects and applied electric fields by SCC-DFTB method

The geometric structure and electrical properties of the zigzag DWSiNT (8,0)@(12,0) and armchair DWSiNT (5,5)@(7,7) perfect tubes with the same diameter are simulated by self-consistent charge density functional tight binding method (SCC-DFTB). We considered the defective tubes by introducing three types of Stone-Wales (SW) defects, and further investigated the impact of both strong and weak electric fields on these defective tubes. Calculations demonstrate that the atomic arrangement regularity, degree of buckling, stability, energy gap, and charge distribution strongly depend on the type of perfect tubes. Following the introduction of the SW defects, the symmetry of the tubes disappeared, and there is a obvious atomic aggregation occurring at the defects. The armchair tubes demonstrate a higher stability compared to zigzag tubes and all exhibit metallic properties. SWⅡ and SWⅢ defects in zigzag tubes result in a transition from semiconductor to semi-metallic properties. The number of charge transfer increases, and the degree of atomic aggregation is more dispersed. The effect of applied electric field strength on perfect zigzag tubes is more obvious. The weak field has minimally impacted on the stability, and the strong field makes the stability improved to some extent. The presence of a strong field caused the energy gap values of (8,0)@(12,0) tube decrease sharply, and all tubes are transformed into semi-metal or metal. The weak electric field has a more pronounced regulation of band gap within the range of 0 V/nm - 0.3 V/nm on the inner tube. The consequences of this investigation can certainly be helpful in future experimental studies.

Optimized shape design and thermal characteristics investigation of helically coiled tube type heat exchanger

The effects of the helical coil tube designs on heat transfer characteristics during heating process were conducted by some researchers and confirmed that the conventional helical coil tube was not the ideal shape for important heat transfer. Despite this, there was no published paper that presented the optimal helical coil structure for important heat transfer. Therefore, this work addresses the influence of different helical coil structure designs on heat transfer characteristics and temperature distribution during heating process. The study was performed for three configurations named constant-diameter coil, variable-diameter coil and variable-pitch coil. Based on CFD simulation, the mathematical model was validated with experimental results and show good agreement. The results suggest that the helical coil with variable-pitch gives the best heat transfer performance compared with other helical coil structure. Among all considered designs, the combined properties of the helical coil with variable-pitch were better than that of other helical coil structures. As a result, this work could provide a shortcut method in the selection of the appropriate helical coil immersed or wrapped on the tank which need the high heat transfer.

Crashworthiness of multicellular tubes with tree-like fractal hierarchical structure under axial impact

A new type of tree-like fractal hierarchical multicellular tubes (TFHMTs) is proposed, and the crashworthiness of the structure under axial impact is studied by using a verified Abaqus/Explicit finite element model. The research results show that the TFHMTs have better energy absorption capacity than single-cell tubes of the same thickness and mass under the same conditions. The wrinkle wavelength of the third-order TFHMTs is significantly shorter than that of the single-cell tubes, resulting in more folds. For the same mass, the proposed third-order TFHMTs has a lower peak crush force than a single-cell tube. Moreover, the specific energy absorption is up to 49.40% greater than that of the single-cell tube, and the crush force efficiency is up to 66.18%. Subsequent parameterization research on the layer ratio coefficient and wall thickness on TFHMTs was systematically conducted. Finally, a comparative analysis with typical hierarchical multicellular tubes was performed.

Turbulent flow of a shear-thinning non-Newtonian CMC-based nanofluid in twisted finned tubes with an elliptical profile

In this article, the forced convective turbulent flow of a shear-thinning non-Newtonian nanofluid through twisted tubes with elliptical cross sections is numerically studied and analyzed at various Reynolds numbers. The base fluid of the studied nanofluid is 0.5% carboxymethyl cellulose solution in water (which has non-Newtonian behavior of shear-thinning), and it contains copper oxide nanoparticles. Two types of twisted tubes are considered: finned tubes and unfinned ones. The finite volume method is utilized, and the two-equation model of k-ε has been applied to analyze the flow characteristics of the turbulent problem. The computational results demonstrate an excellent agreement with respect to already published reports, which is a testament to our reasonable and correct procedure. The effects of pipe wall twisting on the average Nusselt number have been investigated. The achievements demonstrate a powerful secondary and rotating flow is formed with the tube surface twisting. This secondary flow causes better mixing and increases the average Nusselt number. The increase is up to 45% for the unfinned case and 62% for the finned case in comparison with the tube without projections. In addition, the coefficient of friction in these pipes increases to 62% and 104% for the unfinned and finned tubes, respectively. It is also observed that by increasing the length of the fin and adding nanoparticles up to 1.5%, the highest value of the performance evaluation criterion (i.e. 1.78) in the twisted finned tube could be achieved, which occurred at the Reynolds number of 4000. The combination of present geometry and the working fluid of shear-thinning non-Newtonian CMC-based nanofluid is the main novelty of this work, and the results can be applicable and reliable in the relevant industries.

Investigation of the Efficacy of Horizontal Hollow Light Tubes for Energy Conservation in Illuminating Buildings

This study investigates the properties of light transmission and distribution, examining how incident light angles impact illuminance distribution and daylight factor. Light tubes are acknowledged as promising tools to enhance lighting conditions and reduce energy consumption in building design. The study involved installing horizontal hollow light tubes, each measuring 0.5 m in length and 0.30 m in diameter, on a wooden test model. A 20-watt LED lamp was employed as the light source, and an illuminance meter recorded the values at various horizontal and elevation angles. The study’s assessment included calculating the average illuminance and daylight factor to obtain light transmission efficiency and energy-saving potential. The findings revealed that both aluminum alloy and zinc alloy tubes experienced a decrease in illuminance as incident elevation angles increased, with the most effective light transmission occurring at a horizontal angle of 90°. Notably, the aluminum alloy tube outperformed the zinc alloy tube, demonstrating more than a 15% increase in light transmission efficiency. Furthermore, the daylight factor values from both types of tubes aligned with established standards for residential and office activities, underscoring their potential as energy-efficient lighting solutions for spaces lacking natural light or with limited illumination.

Does Cuff Design Impact Insertion andRemoval Force ofTracheostomy Tubes? A Bench Model.

Percutaneous dilatational tracheostomy is a commonly performed procedure in intensive care units. Unrecognized tracheal ring fracture has been suggested as a possible factor for tracheal stenosis. The degree of tracheal compression relates to the amount of force required to cannulate the trachea. The objective of this study was to determine the force required to insert two types of tracheostomy tubes with different cuff designs. This bench model measured the insertion and removal force of two tracheostomy tubes; one with a barrel-shaped, high-volume, low-pressure cuff (traditional Shiley tracheostomy tube) and another with a taper-shaped, low-volume, low-pressure cuff (Shiley flexible tracheostomy tube). Three sizes of tracheostomy tubes either with a barrel- or taper-shaped cuff were tested (Jackson sizes 4, 6, and 10, corresponding to 6.5-, 7.5-, and 10-mm ISO sizes, respectively). A model representing the tissue that the tube traverses to enter the tracheal lumen was designed, and the tracheostomy tube was mounted on a universal testing machine to measure the force necessary to insert and remove the tube. Across all tracheostomy tubes' sizes tested, significantly less force was required to insert the Shiley flexible tracheostomy tube compared to the traditional Shiley tracheostomy tube. Significantly less force was also required to remove the flexible tracheostomy tube compared to the traditional tracheostomy tube. This model suggests that less force is required to insert the Shiley flexible tracheostomy tube, which could result in less tracheal compression. This may be because of the smaller taper-shaped cuff that, when deflated, occupies less volume compared to the barrel-shaped cuff. As a result, less tracheal injury may occur when using the Shiley flexible tracheostomy tube during percutaneous tracheostomy procedures.

Experimental performance analysis of evacuated tube type direct-expansion solar-assisted heat pump system

ABSTRACT The direct-expansion solar-assisted heat pump (DX-SAHP) have proven to be one of the strategies in reducing energy consuming for domestic hot water supply. The poor pressure resistance of the collector, high heat loss from radiation for the traditional bare-plate type DX-SAHP limits its popularization and application. To solve this problem, a DX-SAHP system using evacuated tube type collector-evaporator was proposed in this post. System optimization can not only reduce operating costs, but also results in energy savings. Thus, a DX-SAHP prototype was established and tested under various running conditions to obtain the optimal running parameters. Based on experimental data, the impacts of refrigerant charge, solar radiation intensity, and ambient temperature on the performances of evacuated tube type DX-SAHP system are investigated and evaluated. The outcome indicates that this system coefficient of performance (COP) increases by 73.4% with the decrease of charge amount of refrigerant in the range of 5.66–6.67 kg. And, the average collector efficiency is 0.71 with a refrigerant charge of 5.66 kg. And, the optimal COP of this presented system is 5.27 when an ambient temperature, solar radiation intensity, and refrigerant charge are 26.3°C, 954.37 , and 5.56 kg, respectively.

Investigation on solar drying system with double pass solar air heater coupled with paraffin wax based latent heat storage: Experimental and numerical study

Since solar energy uses the sun's free energy and is environmentally friendly, it is generally accepted for various applications like drying products. However, the drawback of this system is the inconsistent and unpredictable nature of solar radiation. The best solution for the above said problem is using thermal energy storage. In this study forced convection indirect solar drying system that has a double pass solar air heater (DPSAH), shell and tube type latent heat storage (LHS) with paraffin wax as phase change material (PCM), blower and drying chamber is developed and tested. Numerical study is conducted on the DPSAH to determine the effect of mass flow rate on its performance and appropriate flow rate is selected for the drying experiment. It was found that outlet temperatures of the DPSAH is higher at lower mass flow rates and lower at higher mass flow rates and mass flow rate of 0.01 kg/s gives the required outlet temperature. Whereas numerical simulation is done on the LHS to predict the charging and discharging behavior of the PCM and found that the storage can reach a fully charged state within 133 min, which can be achieved around the peak hours during the experiment. The performance of the components of the dryer and the overall performance of the dryer is investigated with experiment. From the experimental result, a maximum temperature of 69 °C is obtained at the outlet of the DPSAH and the energy and exergy efficiencies are 25 % and 1.5 %, respectively. The LHS reduces the fluctuations in the outlet temperature of the SAH and extends the drying process for extra 3 h a day. The drying experiment is conducted by drying 5 kg fish and took 21 h to reduce the moisture content of the fish from an initial value of 75 %–12.5 %. The efficiency of the drying chamber was 35 % and the overall efficiency of the dryer was 9.4 %.

Rapid serum tubes reduce transport hemolysis and false positive rates for high-sensitivity troponin T

IntroductionHemolysis in the emergency department (ED) can significantly delay results and appropriate action. We evaluated the main sources of hemolysis during sample collection, and to evaluate the use of rapid serum tubes (RST) as a transport hemolysis-mitigating measure for high-sensitivity troponin T (hs-cTnT) testing. MethodsWe examined the effect of tube type, tube fill, types of sample draw and collection methods on hemolysis and hs-cTnT in samples (n = 158) from ED patients. We also compared hs-cTnT values in paired RST and plasma separate tube (PST) samples that were hemolysis-free. ResultsThe primary source of hemolysis in samples collected in the ED was underfilling tubes. In both tube types, PST and RST, filled tubes showed a median reduction in hemolysis of 69.1 % (p < 0.0001). Blood collected in RST also experienced less hemolysis compared to PST. In hemolysis-free samples, false positive results in PST were noted in patients with hs-cTnT values < 50 ng/l. ConclusionWe suggest that proper tube filling during sample collection and use of RST tubes can significantly reduce the effects of hemolysis. In addition, laboratories should be aware that PST tubes have a non-trivial rate of false positives when hs-cTnT < 50 ng/l.