Heat-shrinkable Tube Research Articles

Sealing performances of polymer heat-shrinkable tubing for deep rocks under high-temperature and ultrahigh-pressure condition

The deep underground engineering will face high-temperature and ultrahigh-pressure (HTUP) condition. Indoor triaxial testing is an important means to investigate this challenge in rock mechanics and rock engineering. Heat-shrinkable tubing, as a seal on the rock surface, is crucial for reconstructing deep rock in situ conditions (ensuring the accuracy and effectiveness of confining pressure and pore pressure). However, there are few reports on testing such material under HTUP condition. Thus, the mechanical and sealing performances of existing heat-shrinkable tubing under HTUP condition is still immature. The motivation of this study is to advance deep rock mechanics and engineering by developing a polymer heat-shrinkable tubing (pressure larger than 140 MPa and temperature greater than 150 °C). Experiments using the deep rock in situ thermal insulation coring test system were conducted and compared with conventional heat-shrinkable tubing. The sealing performance of the polymer heat-shrinkable tubing was investigated. The results indicated that deep rock ultrahigh-pressure condition and natural damage to the rock surface are the main causes of conventional heat-shrinkable tubing failure. In contrast, the damage rate of the proposed polymer heat-shrinkable tubing is extremely low, indicating that incorporating base material with high-performances can significantly enhance the pressure resistance of polymer heat-shrinkable tubing. Additionally, through the analysis of experimental results and the three-dimensional (3D) morphology of rock surfaces, the failure behavior of heat-shrinkable tubing under HTUP condition was revealed at the meso-structural level, and the proposed failure criteria, taking into account 3D morphology of rock surfaces and applicable to HTUP condition, have been advanced. The findings offer possibilities for triaxial rock mechanics testing in HTUP condition, providing theoretical and technical support for experiments and engineering applications in deep rock mechanics.

An All-Solid-State Ti/RuOx pH Electrode Prepared Based on the Thermal Oxidation Method.

The development of all-solid-state precise pH electrodes holds significant importance in various fields, particularly in marine scientific research. To achieve this goal, we proposed a novel fabrication technique for an all-solid-state ruthenium oxide (Ti/RuOx) pH electrode. We thin-coated the RuCl3 precursor solution on a titanium wire substrate using a heat gun repeatedly and then calcined it in a mixture of Li2CO3 and Na2O2 at 400 °C to obtain a ruthenium oxide (RuOx) film. This RuOx film was subjected to acid treatment with dilute nitric acid, and a polytetrafluoroethylene heat shrink tube was wrapped around the non-RuOx film area. Finally, the RuOx film was fully immersed in a pH 4.00 buffer solution, finalizing the electrode preparation. The RuOx film exhibits a dense and regular conical morphology. The Ti/RuOx electrode demonstrates a good near-Nernstian response slope (e.g., -59.04 mV/pH at 25 °C), high linearity (e.g., R2 = 0.9999), rapid response (<1 s), low hysteresis (<3 mV), excellent reversibility, and good repeatability in the pH range of 2.00-10.00. After full hydration, the Ti/RuOx electrode shows a potential drift of 8.5 mV and a drift rate of approximately 0.27 mV/day over a period of 25 days, indicating good long-term stability. Furthermore, the Ti/RuOx electrode exhibits robust resistance against interference from various ions and low-concentration redox substances, ensuring a long storage life (at least 280 days), and high measurement accuracy (e.g., ± 0.02 pH units) for diverse water samples, including seawater, freshwater, and tap water. This study has evaluated the potential of the Ti/RuOx electrode as a reliable and accurate tool for pH measurements in marine scientific applications.

Development of a flow reactor incorporating polydopamine-poly(ε-caprolactone) with gold particles

Addressing the significant challenge of dye wastewater pollution, this study introduces a novel solution employing a flow catalytic reactor loaded with gold (Au) particles. The reactor utilizes a porous monolithic material with a Poly(ε-caprolactone) (PCL) matrix as the carrier for Au particles, with polydopamine employed to immobilize the Au onto the surface of the PCL monolith. To assess the catalytic efficiency of the reactor, a model catalytic degradation experiment involving the reaction between methyl orange (MO) and sodium borohydride was conducted. The catalytic reaction was facilitated by a peristaltic pump. The reactor setup involved fixing the monolith within a heat shrinkable tube, and the peristaltic pump ensured the flow catalytic reaction. The protective effect of liquid nitrogen was utilized to confirm that the porous structure of the PCL monolith, with its low melting point, remained intact after being fixed in the heat shrink tube. Catalytic results revealed remarkable efficacy, with the decomposition efficiency of MO reaching 98.54%. This flow reactor enables continuous operation, making it more practical for real-world applications compared to traditional batch methods. Furthermore, even after 5 cycles, the sample maintained a catalytic efficiency exceeding 90%, demonstrating the excellent reusability of the reactor.

Functional performance of low-cost electronic yarn for E-textiles

The current work presents and discusses the design and performance qualities of braided electronic yarns for woven textiles to produce red light-intensity effects. The design process involves a simple encapsulation process with adhesive tape and a heat-shrinkable tube to secure stainless-steel conductive threads (SS-CTs) to the solder pads of light-emitting diodes. These are arranged in a series against two SS-CTs to provide single positive and negative terminals at both ends. Findings from the infrared images show that the heat distribution and dissipation of the stainless-steel conductive threads are insignificant in affecting the wear comfort of the electronic textiles on the human body. The washing test shows the robust nature of the braided electronic yarns even after 20 cycles of being subjected to high agitation and mechanical stress. A proof of concept illustrates the effectiveness of the study results, which calls on further research work to enhance the durability and flexibility of the braided electronic yarns and electronic textiles to ensure a higher level of wear comfort. These braided electronic yarns would find end applications for nighttime visibility of pedestrians, a situation that would improve the recognition of drivers for reduced collision.Graphical abstractA simple low-cost process to manufacture electronic yarns (e-yarns) starts by embedding light-emitting diodes (LEDs) in series on two stainless-steel conductive threads (SS-CTs) through encapsulation in a heat-shrinkable tube (HST), and insulating one side of the SS-CT, then braided by using 8-core retroreflective threads that are then woven to form an electronic textile (e-textile). The braided e-yarns and e-textiles when washed exhibit good performance properties for clothing that would be interactive to enhance the nighttime visibility of pedestrians.Impact statementElectronic textiles otherwise known as e-textiles have been the subject of scholarly attention in recent years due to their performance properties and wide areas of application for entertainment, monitoring, and safety purposes. The use of appropriate electronic yarns (e-yarns) plays a key role in connectivity and provides the necessary feedback when applied to a textile material. E-yarns are now replacing a few modern electronic textiles (e-textiles) that use rigid copper wires commonly applied in electronic circuits for e-textiles and improve the wear comfort of the garment. The integration of light-emitting diodes (LEDs) into conductive threads to form electronic yarns for textile material can be applied not only for entertainment purposes but also as a safety feature for pedestrians. The use of appropriate components is necessary to ensure and maintain the textile quality and properties for effective wearability. Herein, an e-yarn fabricated with stainless-steel conductive threads and LEDs for e-textiles is presented. As part of ongoing research work to develop smart interactive clothing to increase the nighttime visibility of pedestrians, this work discusses the design and performance qualities of braided e-yarns for woven textiles. The success of these low-cost, flexible, and strong (high wash durability) braided e-yarns facilitates their integration into woven fabrics for smart clothing to enhance the visibility and therefore safety of pedestrians.

Interventional device tracking under MRI via alternating current controlled inhomogeneities.

To introduce alternating current-controlled, conductive ink-printed marker that could be implemented with both custom and commercial interventional devices for device tracking under MRI using gradient echo, balanced SSFP, and turbo spin-echo sequences. Tracking markers were designed as solenoid coils and printed on heat shrink tubes using conductive ink. These markers were then placed on three MR-compatible test samples that are typically challenging to visualize during MRI scans. MRI visibility of markers was tested by applying alternating and direct current to the markers, and the effects of applied current parameters (amplitude, frequency) on marker artifacts were tested for three sequences (gradient echo, turbo spin echo, and balanced SSFP) in a gel phantom, using 0.55T and 1.5T MRI scanners. Furthermore, an MR-compatible current supply circuit was designed, and the performance of the current-controlled markers was tested in one postmortem animal experiment using the current supply circuit. Direction and parameters of the applied current were determined to provide the highest conspicuity for all three sequences. Marker artifact size was controlled by adjusting the current amplitude, successfully. Visibility of a custom-designed, 20-gauge nitinol needle was increased in both in vitro and postmortem animal experiments using the current supply circuit. Current-controlled conductive ink-printed markers can be placed on custom or commercial MR-compatible interventional tools and can provide an easy and effective solution to device tracking under MRI for three sequences by adjusting the applied current parameters with respect to pulse sequence parameters using the current supply circuit.

Core–shell yarn-structured triboelectric nanogenerator for harvesting both waterdrop and biomechanics energies

Wearable energy harvesters (WEHs) have garnered significant attention recently due to their promising capabilities in powering wearable devices. In this research, we present a core–shell yarn-structured triboelectric nanogenerator (CY-TENG) that operates in two modes: the single-electrode TENG (SE-TENG) and the droplet-based electricity generator. This design facilitates energy harvesting from both waterdrops and biomechanics. The CY-TENG is fabricated using fluorinated ethylene propylene ultrafine heat-shrink tubes combined with stainless-steel yarns, ensuring its flexibility, durability, and weavability. Such attributes underscore its potential as a dual-function WEH.

Ohmic heating curing of carbon fiber concrete beam in realistic cold weather: The influence of electrically insulated steel rebars

This work attempted to investigate the on-site application of ohmic heating curing method on the structural concrete with steel reinforcement. The steel reinforced carbon fiber concrete beams were cured by ohmic heating method in the realistic severely cold weather. It was found that steel rebars disturbed the electrically conductive network formed by carbon fibers, resulting in a reduced curing duration of 48 h and an abnormal temperature distribution with high corner temperature and low core temperature. Electrical insulation treatments (epoxy resin coating and heat-shrink tubing) were taken and evaluated based on the ohmic heating features and mechanical properties. The results showed that the epoxy resin coating had a limited insulation effect, with an electrical resistance of 3.9 Ω, which displayed a similar temperature distribution with the uninsulated beam. On the contrary, the heat-shrink tubing had a significant insulation effect with an electrical resistance of 36.5 Ω, leading to an average core temperature of 23.6 ℃ during 7 days of curing period. The average rebound strength of beams with epoxy resin coating and heat-shrink tubing was 34.0 MPa and 41.6 MPa, respectively, and the ultimate deflection of beams was 34.37 mm and 49.18 mm, respectively, which was in correspondence with the temperature distribution. Besides, the heat-shrink tubing increased crack spacing width of beam, while the epoxy resin had little influence on crack pattern. This work emphasized the importance of electrically conductive path of concrete for ohmic heating curing method and gained practical experience of this method on the structural concrete.

Relationship between Bubble Generation Behavior and Hydrogen Evolution Performance at High Current Densities during Alkaline Water Electrolysis

Introduction Alkaline water electrolysis (AWE) has attracted considerable attention as a method to produce hydrogen. However, one of the problems with AWE is the increase in overpotential, which is attributed to bubbles covering the electrode surface at high current densities. Therefore, it is important to understand the bubble generation behavior to develop strategies for reducing the overpotential. In this study, we observed bubble generation behavior on Platinum (Pt) electrodes using a high-speed camera [1] and conducted electrochemical measurements to investigate the relationship between the current density/electrode potential and bubble generation behavior. Experiments Pt wires with diameters of 200 μm were used as the working electrodes. The reference and counter electrodes were a reversible hydrogen electrode (RHE) and Ni rods with a diameter of 3 mm, respectively. All measurements were conducted using a three-electrode electrochemical cell with a 2 M KOH aqueous solution as the electrolyte at 303±1K. To minimize the solution resistance, the working and reference electrodes were positioned as close as possible to each other, with a separation distance of approximately 2 mm. To ensure a uniform current-density distribution, a Ni-rod counter electrode was inserted on both sides of the cell. Observation windows were installed on the sides of the cells. Only a 3-mm parallel section of the working-electrode wire was exposed to the electrolyte to observe the electrolytic reaction, while the rest of the wire was covered with PTFE heat-shrink tube and epoxy resin. After appropriate pretreatment, cyclic voltammetry (CV) measurements were performed at a scan rate of 5 mV s-1 to obtain the polarization curves. Electrochemical impedance spectroscopy (EIS) measurements were conducted at −0.2 to −0.8 V vs. RHE with a potential amplitude of 10 mV, over a frequency range of 3×105 to 1 Hz, where 60 repeated measurements were performed for each frequency. The solution resistance was obtained from Cole–Cole plots and corrected for potential losses. The current density (i geo / A cm-2) was normalized by the geometric surface area of the cylindrically shaped working electrode. Constant current electrolysis was performed under twelve conditions of i geo = −0.05 to −1.5 A cm-2. Under each condition, the formation behavior of hydrogen bubbles was photographed using a high-speed video camera. Results and discussion Figures 1 and 2 show the polarization curves at the cathode and anode, respectively [2]. The overvoltage increased with i geo, as evidenced by the shift of the polarization curves from Tafel slope, in the range of −i geo ＜ 0.9 A cm−2 at the cathode and in the range of i geo > 0.6 A cm−2 at the anode. Figure 3 shows Cole–Cole plots obtained at i geo = −1.0 A cm−2 at the cathode and Figure 4 shows Cole–Cole plots obtained at i geo = 1.0 A cm−2 at the anode [2]. Figure 5 shows the hydrogen bubble generation behavior obtained at i geo = −1.0 A cm−2 at the cathode, and Figure 6 shows oxygen bubble generation behavior obtained at i geo = 1.0 A cm−2 at the anode [2]. The Cole–Cole plots indicate the resistance component on the low-frequency side at high current densities in addition to the charge transfer resistance. Moreover, the arc shapes of the resistance components differ between the anode and cathode, suggesting that different mechanisms are responsible for the increase in the overvoltage at high current densities. We believe that these resistances arise from reactant transfer limitations due to the hydrogen and oxygen bubble layers covering the electrode surfaces. Moreover, it was also confirmed that the charge-transfer resistance is inversely proportional to the current density, indicating that the effective electrode surface area does not change over a wide range of current densities. By comparing Figures 5 and 6, it was observed that oxygen bubbles at the anode where a larger overvoltage increase than cathode was measured had larger diameters and were less likely to detach from the electrode. Furthermore, the bubble layer formed on the electrode surface was thicker on the anode than on the cathode. Acknowledgements Part of this study was based on results obtained from the Development of Fundamental Technology for Advancement of Water Electrolysis Hydrogen Production in the Advancement of Hydrogen Technologies and Utilization Project (JPNP14021), commissioned by the New Energy and Industrial Technology Development Organization (NEDO).

Determination of Harness Production Time and Defective Product Formation Risk Factors with Artificial Neural Network

The aim of this research is to estimate the projected production times of the cable harnesses produced for the tender in a company operating in the aviation and defense industry in our country by artificial neural network. For this, artificial neural network model has been formed for the number of work order, the number of cable harness module, the number of cable harness pin, the number of cable harness label, the number of cable harness back shell, the number of cable harness heat shrink tube, and the number of cable harness terminal variables which may have an effect on the projected production times of cable harnesses for the tender. Multiple linear regression analysis method is used to compare the predictive power of this model and the most appropriate method for estimating the projected production time of cable harnesses for the tender is provided. The aim of the research is to determine the effect of cable harness connector type, cable harness label type and personnel competence level risk factors on the formation of faulty cable harnesses determined during the quality control and electrical testing steps in the production process using logistic regression analysis.

Multifilament HTS Cables to Reduce AC Loss: Proof-of-Concept Experiments and Simulation

Reducing AC losses of HTS is essential for AC application since it can lower the constraint on the cryogenic cooling demand. Several studies have reported that the manufacturing of multi-filament HTS cables can reduce AC loss. However, large coupling losses were identified in the existing cables, due to the existence of coupled copper or soldering layers. We report in this paper a novel way to develop multi-filament HTS cables, mainly focusing on suppressing the coupling losses by reducing the contact resistivity within the HTS cables. Heat shrink tubes are used to directly insulate narrow HTS filaments into a cable structure. Sample cables were made with 4 mm and 2 mm wide HTS strips. Both transport losses and total AC losses in a rotational magnetic field were measured to quantify the AC loss reduction for the multi-filament HTS cables. The measurements were used to validate the modelling results, and to predict AC loss reduction for 1 mm wide HTS cable. The results showed loss reduction up to around 90% in the 1mm wide HTS cable compared with 4 mm cable. As a result, the proposed multi-filament HTS cables will have promising applications in reducing AC loss.

Dual-parameter sensing of temperature and strain realized by two π-PSFBGs cascaded

This paper investigates the dual-parameter sensing of temperature and strain using π-phase-shifted fiber Bragg gratings (π-PSFBGs). In many practical engineering applications, temperature and strain are often present simultaneously, which can interfere with each other's sensing. To achieve dual-parameter sensing of temperature and strain, two π-PSFBGs are modified with phase-shifted peaks of 1547 nm and 1550 nm, respectively. The π-PSFBG of 1547 nm is wrapped with a heat shrinkable tube to increase its temperature sensing sensitivity by 185.6%, while its strain sensing sensitivity is reduced by 91.083%. The π-PSFBG of 1550 nm is coated with indium tin oxide (ITO) film using the pulsed laser deposition (PLD) method to increase its temperature sensing sensitivity by 22.3%, while its strain sensing sensitivity is reduced by 16.03%. Finally, the two modified π-PSFBGs are cascaded to realize dual-parameter sensing of temperature and strain. The ITO film coating on the surface and heat shrinkable tube wrapping can reduce the interference of external light on the signal light and protect the fiber grating. By setting the optical spectrum analyzer (OSA) accuracy to 0.02 nm, the sensing information can be extracted by scanning within a few nanometers, and the sharp phase-shifted peak of the π-PSFBG helps accurately locate the signal wavelength. The results demonstrate the potential for the practical application of the proposed dual-parameter sensing method.

Tracking, Erosion and Morphological Study of Heat Shrink Anti Tracking Tubes

Components of Medium Voltage (MV) cable network are very much vulnerable under operational stresses and ageing. Heat Shrinkable Anti-Tracking Tube (HSATT), an integral part of the Joints and terminations of the MV cable network system is used to cover and safeguard the power cable joints. In cable system joint and termination are the weakest but the critical part and fail easily under stress. The most threatening source of HSATT failure is electrical tracking. Electrical tracking develops when a conducting path across the HSATT formed under electric stress due to surface discharge. Arcs created from this surface discharge phenomenon burn the HSATT and create carbonized tracks in the long run. This paper reports the electrical tracking performance of three commercially available HSATT samples. Crosslinked polyethylene (XLPE) is the key ingredient for heat shrinkable materials. Electrical tracking using the inclined-plane tracking (IPT) method develops from surface discharge activity followed by erosion under wet and contaminated conditions. So, the material under IPT test faced electrical, environmental and thermal stresses. Among these three HSATT samples two samples failed to withstand these three dimensional stress factors. Dielectric breakdown strength and volume resistance tests were carried out to cross examine the IPT results and the results are identical. The morphology has been studied to understand the failure mechanism of HSATT samples. A morphological model is presented to scrutinize the IPT test failure mechanism and the rate of erosion propagation in the HSATT samples.

Measurement of Rock Electrical Parameters and Analysis of Influencing Factors of Quaternary Mudstone Biogas Reservoirs in Qaidam Basin

As a new and unconventional reservoir, Quaternary mudstone biogas reservoirs in the Qaidam Basin are widely distributed and thick. They have great potential for biogas exploration. However, the mudstone biogas reservoirs in this area characterized by weak cementation, high clay content, and easy hydrolysis. Using existing methods, it is difficult to obtain the rock electrical parameters and evaluate the saturation. This greatly affects the evaluation of oil and gas reserves. This study selected core samples from the Quaternary mudstone biogas reservoir in Qaidam Basin, prepared the samples through core conformation pretreatment, and conducted rock electrical experiments using the self-absorption water augmentation method to obtain the rock electrical parameters of the mudstone biogas reservoirs for the first time. Then, the factors influencing the rock electrical parameters of the mudstone biogas reservoir were analyzed. The results showed that: (1) the porosity of the mudstone core samples was generally greater than 20%, and the permeability was in the range of 0.05–5 mD. The rock mineral composition was dominated by clay minerals, followed by carbonate minerals, quartz, and feldspar. The clay mineral composition was mainly illite, followed by montmorillonite and chlorite, with a small amount of kaolinite. (2) The use of wire-electrode cutting and high-temperature, heat-shrinkable tube to wrap the core sample played a supporting and protecting role in the core. Using the self-absorption water augmentation method, information was obtained showing that the distribution of cementation index m of the reservoir core samples ranged between 1.89–2.08, with an average value of 1.99, and the distribution of saturation index n ranged between 1.872–2.270, with an average value of 2.09. (3) Organic matter content had no obvious effect on rock electrical parameters. With the decrease of clay mineral content, the quartz content increased, the permeability increased, and the cementation index increased gradually. The saturation index increased with the increase in clay mineral content and the decrease of quartz content and permeability. The above results laid a petrophysical basis for the evaluation of the saturation of mudstone biogas reservoirs and could provide technical support for the comprehensive evaluation of the reservoir and the calculation of reserves.

Experimental Study of the Chemical Composition and Evaluation of Microhardness of the Main Component of Heat-Shrinkable Tubing

In this paper, a heat-shrinkable InnoSHRINK XTFS tubing with diameters of10 cm is investigated. The chemical composition is determined by the infrared spectroscopy using the absorption spectrum within the range of 5000500 cm-1 with a resolution of 4 cm-1 and the number of scans of 32 of the main heat-shrinkable component of the textile fabric. Based on the obtained dependence, it is concluded that the main heat-shrinkable component is polyolefin monofilament. Polyolefin monofilament must be modified to have a shape memory effect in order to acquire the ability to shrink. Its microhardness is calculated to identify suitable operating conditions of materials made from such filaments. Microhardness allows you to choose the maximum load on the material. Previously, microhardness was determined only for compressed polyolefin samples. The author has successfully carried out the evaluation of microhardness for a single textile thread by melting it into a slot with Wood alloy.

Aerosol based synthesis of highly conducting carbon nanotube macro assemblies by novel mist assisted precursor purging system

Taking hardware complexity into consideration of traditional continuous precursor purging systems for synthesis of few wall carbon nanotubes (CNTs) is a big challenge. Therefore, a novel precursor purging system for aerosol formation is designed to achieve uniform diameter distribution of CNTs, with the aerosol flow rate controlled either by number of ultrasonic mist makers or flow rate of carrier gas. Large droplets are turned into aerosol via an as-customized mist-producing system without the use of temperature or any chemical reaction. A built-in atomized gas valve is used to introduce the aerosol into a floating catalyst chemical vapour deposition (FCCVD) reactor. After an influential comparison of as-customized purging systems to the mostly used complex and big-budget systems for uniform diameter distribution, the quality of these CNT assemblies, synthesized using two different carrier gases (argon and hydrogen) is examined. Herein, CNT sheets with mostly fewer walls CNTs (diameter 2–10 nm) have been synthesized using this approach, with the controlled size of catalyst nanoparticles, under H2 atmosphere exhibiting low sulphur impurities, as evidenced by Raman, EDS, and XPS spectra, and have a fourteen-fold greater electrical conductivity (5.78 × 104S/m) than those synthesized under Ar atmosphere. Moreover, these sheets are also twisted and wrapped by insulating heat shrink tubes. The maximum current density of these conducting CNT wires having 250 µm diameter is 8.15 × 106A/m2. Further, one of the domestic applications of LED bulb (3–45 W) lightning is also demonstrated which shows the suitability of these conducting wires in numerous hi-profile applications.

Simulation Study of High Sensitivity Fiber SPR Temperature Sensor with Liquid Filling.

In this paper, a high sensitivity fiber temperature sensor based on surface plasmon resonance is designed and studied. In the simulation, the single mode fiber is polished to remove most of the cladding, and then gold and silver films are added. Finally, it is embedded in the heat shrinkable tube filled with a thermo-optic coefficient liquid for curing. The numerical simulation results show that the sensing characteristics are sensitive to the remaining cladding thickness of the fiber, the thickness of the gold film and the thickness of the silver film. When the thermo-optic coefficient of the filling liquid is −2.8 × 10−4/°C, the thickness of the gold film, the thickness of the silver film and the thickness of the remaining cladding of the fiber are 30 nm, 20 nm and 1 μm, respectively. The sensitivity of the sensor designed in this paper can reach −6 nm/°C; this result is slightly higher than that of similar research in recent years. It will have a promising application prospect in flexible wearable temperature sensors, smart cities and other fields.

Development of Stainless Steel Yarn with Embedded Surface Mounted Light Emitting Diodes.

The integration of electronic components in/onto conductive textile yarns without compromising textile qualities such as flexibility, conformability, heat and moisture transfer, and wash resistance is essential to ensuring acceptance of electronic textiles. One solution is creating flexible and stretchable conductive yarns that contain tiny surface-mounted electronic elements embedded at the fiber level. The purpose of this work was to manufacture and subsequently evaluate the physical features and electromechanical properties of stainless steel yarn with light-emitting surface mounted devices (SMDs) embedded in it. The SMDs were successfully integrated into a conductive stainless steel yarn (SS) by inserting crimp beads and creating a bond through hot air soldering machines, resulting in what we call an E-yarn. The relationship curves between gauge length and electrical resistance, and the relationship curves between conductive yarn elongation and electrical resistance, were explored experimentally. The results of the analysis demonstrated that E-yarn had a lower tensile strength than the original electrically-conductive SS yarn. The effects of the washing cycle on the conductivity of the E-yarn were also investigated and studied. The results showed that E-yarns encapsulated at the solder pad by heat shrink tube still functioned well after ten machine wash cycles, after which they degraded greatly.

A flexible and robust double-helix tubular cloth/carbon fibers piezoresistive sensor for human motion detecting

Cloth-based piezoresistive sensors with weaved microstructures have become very attractive wearable electronics due to their cost-effectiveness, high sensitivity, and simple fabrication. Here, a double-helix tubular cloth/carbon fibers (CFs) piezoresistive sensor (DTCPS) is successfully produced and tightly encapsulated by a polyethylene heat shrinkable tube that reveals prominent reliability (20000 s fatigue tests) and agile response speed (response time of 31 ms). Owing to the synergistic effect of microstructures of tubular cloth and relatively large contact area of CFs, the DTCPS demonstrates the wide pressure measurement range from 3 N to 480 N and the high sensitivity of 0.178 N−1 (3 N ∼ 330 N). Considering the excellent output performances, the DTCPS is used to detect the human motion postures and is possibly expected to be applied in the fields of artificial intelligence and individualized medical care.

Gamma Radiation Processed Polymeric Materials for High Performance Applications: A Review.

The polymeric properties are tailored and enhanced by high energy radiation processing, which is an effective technique to tune the physical, chemical, thermal, surface, and structural properties of the various thermoplastic and elastomeric polymeric components. The gamma and electron beam radiation are the most frequent radiation techniques used for crosslinking, compatibilizing, and grafting of various polymer blends and composites systems. The gamma radiation-induced grafting and crosslinking are the effective, rapid, clean, user-friendly, and well-controlled techniques for the polymeric materials for their properties improvement for high performance applications such as nuclear, automobile, electrical insulation, ink curing, surface modification, food packaging, medical, sterilization, and health-care in a different environment. Similarly, electron beam radiations crosslinking has been a well-known technique for properties development and has economic benefits over chemical crosslinking techniques. This review focuses on the development of polymeric multi component systems (functionalized polymer, blends, and nanohybrids), where partially nanoscale clay incorporation can achieve the desired properties, and partially by controlled high energy radiations crosslinking of blends and nanocomposites. In this review, various investigations have been studied on the development and modifications of polymeric systems, and controlled dose gamma radiation processed the polymer blends and clay-induced composites. Radiation induced grafting of the various monomers on the polymer backbone has been focused. Similarly, comparative studies of gamma and electron beam radiation and their effect on property devlopment have been focused. The high energy radiation modified polymers have been used in several high performance sectors, including automotive, wire and cable insulation, heat shrinkable tube, sterilization, biomedical, nuclear and space applications.

Design of a C60 Structural Model Based on Transistors Linked With Plastic Tubes

Buckminsterfullerene (C60), along with diamond and graphite, appears in many chemistry textbooks as an example of an allotrope of carbon. This communication describes a hands-on activity to explore the characteristic structure of C60 through the construction of a structural model using transistors and plastic tubes (heat-shrink and silicone). Transistors resemble sp2 carbons when their three electrodes are spread 120° in relation to each other. The heat-shrink tube is suitable for connecting thin electrodes of transistors. By connecting 60 transistors using 90 precut plastic tubes, a C60 model can be built that costs about 2.1 USD. This activity was carried out with nonchemistry majors using a remote lecture system. The participants enjoyed constructing their C60 models and were challenged to estimate the diameter of an actual C60 molecule using the models that they had built.