High Thermal Sensitivity Research Articles

Polyethylene crosslinking using the epoxy‐anhydride reaction I: A strategy for a curing process with high thermal sensitivity

AbstractThe initiated epoxy‐anhydride reaction was examined as a crosslink motif for effecting cure in functionalized polyethylene for electrical cable insulation applications. A specific challenge for this application is that little to no crosslinking can occur during the processing steps (~140°C), but crosslinking must be rapid and complete within a few minutes during the curing process (~200°C). To achieve this, we coupled the kinetics of the formation of an initiator for the epoxy‐anhydride reaction to the crosslinking step to achieve a phenomenological temperature sensitivity or “latency” that would be difficult to access via a single simple reaction. Evaluations of different imidazolium and phosphonium salts as initiator precursors were conducted with model compounds in solution, and specific salts were chosen for polymer studies based on the ratio of the phenomenological rates measured for the model reaction at ~140°C and ~200°C. In polymer studies using epoxide‐functional poly(ethylene), high crosslinking rates were observed at ~200°C while crosslinking was minimal at ~140°C. However, inclusion of the anhydride‐functional polyethylene in the formulation led to loss of initiator latency, and significant crosslinking was observed at ~140°C. A reaction between the anhydride or an impurity and initiator precursor is postulated to produce a kinetically‐competent initiator at lower temperatures that destroys latency.

CMOS-Compatible and Temperature Insensitive C-Band Wavelength (De-)multiplexer

The high thermal sensitivity of the Silicon Photonics (SiP) platform compromises the performance of variant devices and increases the power consumption to stabilize the temperature. To address this issue, we demonstrate a CMOS-compatible and temperature insensitive <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 4$ </tex-math></inline-formula> C-band wavelength division (de-)multiplexer on the 220-nm-thick silicon-on-insulator platform. The (de-)multiplexer design is based on cascading Mach-Zehnder interferometers (MZIs). The waveguide widths of the MZI delay lines are matched to decrease the overall thermo-optic coefficient (TOC). For comparison, an MZI-based (de-)multiplexer with uniform delay lines is also fabricated on the same chip. The transmission spectra of the proposed and reference devices are measured when the wavelength is swept from 1500 nm to 1600 nm and the temperature is varied from 293.15 K to 323.15 K. The measured results show that the TOCs of the proposed and reference device are 4.8 pm/K and 85 pm/K, respectively. This power-efficient multiplexer with high integration density is promising for data center applications.

Impact of Sc3+-Modified Local Site Symmetries on Er3+ Ion Upconversion Luminescence in Y2O3 Nanoparticles.

Rare earth (RE) doped yttria sesquioxide has been widely used as host materials for upconversion (UC) phosphors due to their high refractive index, wide band gap, and high melting point. Meanwhile, while fluoride matrices with low phonon cutoff energies exhibit stronger UC emissions, RE-doped oxides exhibit better thermal stability and higher thermal sensitivity when applied as optical temperature sensors. In this work, Sc3+ is substituted in RE-doped Y2O3 lattices to generate smaller cation sites, enhancing the crystal field and modifying the allowed optical transitions. Er3+ is used as a photoluminescent probe to study the effect of site position and symmetry on the UC performance. In comparison with the traditional hydrothermal method, Sc3+ is successfully incorporated into the Y2O3 lattice via the co-precipitation/molten salt method without segregating observed. The Judd–Ofelt analysis was applied to determine the local symmetry and efficiency changes. Sc was found to be able to improve the luminescence performances of Er in Y2–xScxO3 (YScO) hosts by adjusting the local symmetry level around the luminescent sites. The local symmetry level was reduced with less than 30 mol % of Sc doping concentration based on the changes in Ω2 values. Meanwhile, the YScO oxide was found to significantly improve the luminescence intensity and red-to-green ratio at a lower Yb3+ concentration (5 mol %) instead of a higher concentration (20 mol %) commonly used. This was attributed to an increased energy transfer between the closer Yb3+–Er3+ pairs. Overall, this work allows the spatial occupancy of luminescence centers in the metal oxide host materials to optimize the UC luminescence performance and develop a high-efficiency oxide material for high-temperature applications such as optical thermometry.

UV-laser annealing for improved resistive switching performance and reliability of flexible resistive random-access memory

Flexible resistive random-access memory (RRAM) has attracted significant attention owing to the strong demand for various flexible electronic memory devices. However, fabricating reliable and flexible RRAM is a significant challenge because of the inherently high thermal sensitivity of plastic substrates. In this study, a high-performance flexible RRAM device was fabricated without deforming a plastic substrate by utilizing a precisely controlled UV laser annealing process. The application of laser annealing in an Al/ZnO/Al flexible RRAM changes the concentration of O Frenkel defect pairs in the ZnO layer and produce a ZnO/Al mixed interface layer with high quality oxygen reservoirs. The higher concentration of O Frenkel defect pairs in the ZnO layer induces electroforming-free process, and the improved characteristics such as crystallinity, morphology, and stoichiometry of the interface area result in stable resistive switching and performance enhancement in the flexible RRAM. The laser-annealed flexible RRAM exhibits a high on/off ratio (~1.07 × 10 4 ), high cycling endurance (up to 2.5 ×10 3 cycles), and low power consumption (4.88 µW in SET state and 1.21 µW in RESET state). Importantly, the performance was maintained at a bending radius of up to 5 mm. • Laser annealing process induces a high concentration of O Frenkel defect pairs in the ZnO and forms the ZnO/Al mixed interface layer. • Laser annealing induces the EF-free process and improves the performance and reliability of flexible RRAM. • Laser annealing process does not deform flexible substrate.

Role of PSS-based assemblies in stabilization of Eu and Sm luminescent complexes and their thermoresponsive luminescence

The present work introduces self-assembled polystyrenesulfonate (PSS) molecules as soft nanocapsules for incorporation of Eu3+-Sm3+ complexes by the solvent exchange procedure. The high levels of Eu3+- and Sm3+-luminescence of the complexes derives from the ligand-to-metal energy transfer, in turn, resulted from the complex formation of Eu3+and Sm3+ ions with the three recently synthesized cyclophanic 1,3-diketones. The structural features of the ligands are optimized for the high thermal sensitivity of Eu3+- luminescence in DMF solutions. The PSS-nanocapsules (∼100 nm) provide both colloid and chemical stabilization of the ultrasmall (3–5 nm) nanoprecipitates of the complexes, although their luminescence spectra patterns and excited state lifetimes differ from the values measured for the complexes in DMF solutions. The specific concentration ratio of the Eu3+-Sm3+ complexes in the DMF solutions allows to tune the intensity ratio of the luminescence bands at 612 and 650 nm in the heterometallic Eu3+-Sm3+ colloids. The thermal sensitivity of the Eu3+- and Sm3+-luminescence of the complexes derives from the static quenching both in PSS-colloids and in DMF solutions, while the thermo-induced dynamic quenching of the luminescence is significant only in DMF solutions. The reversibility of thermo-induced luminescence changes of the Eu3+-Sm3+ colloids is demonstrated by six heating-cooling cycles. The DLS measurements before and after the six cycles reveal the invariance of the PSS-based capsule as the prerequisite for the recyclability of the temperature monitoring through the ratio of Eu3+-to- Sm3+ luminescence.

Fabrication of CL-20/HMX Cocrystal@Melamine-Formaldehyde Resin Core-Shell Composites Featuring Enhanced Thermal and Safety Performance via In Situ Polymerization.

Safety concerns remain a bottleneck for the application of 2,4,6,8,10,12-hexanitro- 2,4,6,8,10,12-hexaazaisowurtzitane (CL-20)/1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX) cocrystal. Melamine–formaldehyde (MF) resin was chosen to fabricate CL-20/HMX cocrystal-based core–shell composites (CH@MF composites) via a facile in situ polymerization method. The resulted CH@MF composites were comprehensively characterized, and a compact core–shell structure was confirmed. The effects of the shell content on the properties of the composites were explored as well. As a result, we found that, except for CH@MF–2 with a 1% shell content, the increase in shell content led to a rougher surface morphology and more close-packed structure. The thermal decomposition peak temperature improved by 5.3 °C for the cocrystal enabled in 1.0 wt% MF resin. Regarding the sensitivity, the CH@MF composites exhibited a significantly reduced impact and friction sensitivity with negligible energy loss compared with the raw cocrystal and physical mixtures due to the cushioning and insulation effects of the MF coating. The formation mechanism of the core–shell micro-composites was further clarified. Overall, this work provides a green, facile and industrially potential strategy for the desensitization of energetic cocrystals. The CH@MF composites with high thermal stability and low sensitivity are promising to be applied in propellants and polymer-bonded explosive (PBX) formulations.

Thermostability mechanisms of β-agarase by analyzing its structure through molecular dynamics simulation.

Agarase is a natural catalyst with a good prospect in the industry. However, most of the currently discovered β-agarases are unsuitable for relatively high-temperature and high-pressure conditions required by industrial production. In this study, molecular dynamics simulations were first used to investigate the dynamic changes of folding and unfolding of mesophile and thermophile β-agarases (i.e., 1URX and 3WZ1) to explore the thermostability mechanism at three high temperatures (300 K, 400 K, and 500 K). Results showed that the sequence identity of 3WZ1 and 1URX reaches 48.8%. 1URX has a higher thermal sensitivity and less thermostability than 3WZ1 as more thermostable regions and hydrogen bonds exist in 3WZ1 compared with 1URX. The structures of 1URX and 3WZ1 become unstable with increasing temperatures up to 500 K. The strategies to increase the thermostability of 1URX and 3WZ1 are discussed. This study could provide insights into the design and modification of β-agarases at a high temperature.

High spatiotemporal variability of methane concentrations challenges estimates of emissions across vegetated coastal ecosystems.

Coastal methane (CH4) emissions dominate the global ocean CH4 budget and can offset the “blue carbon” storage capacity of vegetated coastal ecosystems. However, current estimates lack systematic, high‐resolution, and long‐term data from these intrinsically heterogeneous environments, making coastal budgets sensitive to statistical assumptions and uncertainties. Using continuous CH4 concentrations, δ13C‐CH4 values, and CH4 sea–air fluxes across four seasons in three globally pervasive coastal habitats, we show that the CH4 distribution is spatially patchy over meter‐scales and highly variable in time. Areas with mixed vegetation, macroalgae, and their surrounding sediments exhibited a spatiotemporal variability of surface water CH4 concentrations ranging two orders of magnitude (i.e., 6–460 nM CH4) with habitat‐specific seasonal and diurnal patterns. We observed (1) δ13C‐CH4 signatures that revealed habitat‐specific CH4 production and consumption pathways, (2) daily peak concentration events that could change >100% within hours across all habitats, and (3) a high thermal sensitivity of the CH4 distribution signified by apparent activation energies of ~1 eV that drove seasonal changes. Bootstrapping simulations show that scaling the CH4 distribution from few samples involves large errors, and that ~50 concentration samples per day are needed to resolve the scale and drivers of the natural variability and improve the certainty of flux calculations by up to 70%. Finally, we identify northern temperate coastal habitats with mixed vegetation and macroalgae as understudied but seasonally relevant atmospheric CH4 sources (i.e., releasing ≥ 100 μmol CH4 m−2 day−1 in summer). Due to the large spatial and temporal heterogeneity of coastal environments, high‐resolution measurements will improve the reliability of CH4 estimates and confine the habitat‐specific contribution to regional and global CH4 budgets.

Self-Calibration Technique with Lightweight Algorithm for Thermal Drift Compensation in MEMS Accelerometers.

Capacitive MEMS accelerometers have a high thermal sensitivity that drifts the output when subjected to changes in temperature. To improve their performance in applications with thermal variations, it is necessary to compensate for these effects. These drifts can be compensated using a lightweight algorithm by knowing the characteristic thermal parameters of the accelerometer (Temperature Drift of Bias and Temperature Drift of Scale Factor). These parameters vary in each accelerometer and axis, making an individual calibration necessary. In this work, a simple and fast calibration method that allows the characteristic parameters of the three axes to be obtained simultaneously through a single test is proposed. This method is based on the study of two specific orientations, each at two temperatures. By means of the suitable selection of the orientations and the temperature points, the data obtained can be extrapolated to the entire working range of the accelerometer. Only a mechanical anchor and a heat source are required to perform the calibration. This technique can be scaled to calibrate multiple accelerometers simultaneously. A lightweight algorithm is used to analyze the test data and obtain the compensation parameters. This algorithm stores only the most relevant data, reducing memory and computing power requirements. This allows it to be run in real time on a low-cost microcontroller during testing to obtain compensation parameters immediately. This method is aimed at mass factory calibration, where individual calibration with traditional methods may not be an adequate option. The proposed method has been compared with a traditional calibration using a six tests in orthogonal directions and a thermal chamber with a relative error difference of 0.3%.

Thermomechanical Modeling and Optimization of Zero-Power Micromechanical Photoswitch

This paper presents an in-depth thermomechanical analysis of zero-power micromechanical photoswitches (MPs) aiming at aggressive performance enhancement for applications that require ultralow infrared (IR) detection threshold. An accurate analytical model was first derived and used to maximize the thermal sensitivity of the MPs through a loop-based optimization program. With specific pre-defined boundary conditions, such a program can be used to generate a set of device geometrical parameters leading to highest possible thermal sensitivity without sacrificing the structural strength of the device (i.e., spring constant), which otherwise will have to be done with time-consuming numerical simulations. The optimized MPs show more than 4 times improvement in thermal sensitivity compared to previous demonstrations, thanks to the high thermal resistance and temperature sensitivity achieved using the thermomechanical model. The demonstrated theoretical analysis and thermomechanical optimization methods for the MPs are critical for the development of the next-generation zero-power IR sensors specifically designed for applications that require ultra-sensitive IR detection capability without compromising their sensor size, weight and power consumption. [2021-0231]

Optical Temperature Sensor Capabilities of the Green Upconverted Luminescence of Er3+ in La3NbO7 Ceramic Powders

We present a study of the Er3+ upconverted luminescence in erbium doped Lanthanum Niobium Oxide, La3NbO7, ceramic powder, prepared by solid state reaction. This study focuses on the analysis of the feasibility of this system as a temperature sensor. Efficient UC luminescence was observed under the 975 nm excitation showing intense green, red and NIR (850 nm) emission bands. The NIR luminescence centred at about 850 nm and lying on the first biological window is mainly insensitive to the temperature. In contrast, the upconverted green bands, associated with the (2H11/2,4S3/2) →4I15/2 transitions, showed a high sensibility to temperature. Their temperature dependence was studied from RT up to 525 K, paying special attention to the physiological range of temperature (303–318 K). The high thermal sensitivities obtained, in comparison with other Er3+ and Er3+-Yb3+ based optical temperature sensors in such ranges, suggest the potential application of this phosphor in thermal sensing, suitable for both biological systems and other industrial applications requiring higher temperatures.

Thermal comfort of Frail People under dynamic and non-uniform thermal environments using a thermal manikin with thermoregulatory control: An experimental study

The thermal comfort of frail people has to be considered carefully, mainly because of the high thermal sensitivity of this population and the negative influences that unsatisfactory thermal conditions have on their health. Most existing thermal comfort works have been conducted under steady-state, uniform thermal environments, with far fewer being performed in dynamic and non-uniform thermal environments, and even less for frail people. This study aimed at assessing the thermal responses of frail people under transient and non-uniform thermal environments, using a thermal manikin and a climatic test cell. Thermal responses were investigated and discussed in both genders. The analysis of variance showed a significant difference in thermal comfort and thermal sensation between females and males over time, under hot exposure. Under cold exposure, results showed a significant difference in thermal sensation between females and males over time, but no significant difference was observed in term of thermal comfort. Analysis revealed also significant differences in the dynamic thermal sensation between the sexes under cold exposure, while results confirmed that there is no significant difference in the dynamic thermal sensation between sexes under hot exposure.

The rheology of ultra-high molecular weight poly(ethylene oxide) dispersed in a low molecular weight carrier.

Gel spinning is the industrial method of choice for combining hydrophilic ultra-high molecular weight (UHMW) polymer resins with a hydrophobic support polymer to produce composite filaments for cytapheresis. Cytapheresis is a medical technique for removal of leukocytes from blood. Gel spinning is used to avoid high melt viscosity and thermal sensitivity of UHMW resins and the high melt temperature of the substrate resin but requires the recovery of toxic solvents. The UHMW resin is used because it forms a stable gel phase in the presence of water; a lower molecular weight resin (LMW) simply dissolves. UHMW and LMW resins were both poly(ethylene oxide) (PEO) and the substrate was polyarylsulfone (PAS). The literature indicated PEO undergoes non-oxidative thermal degradation above 200 °C and PAS is processed up to 350 °C. Dynamic oscillatory shear rheometry was used to study 0, 25, 40, 50, 60, and 75 wt. % UHMW PEO in LMW PEO to take advantage of the sensitivity of viscosity to changes in molecular weight and material configuration, indicating degradation. Samples were exposed to 220 °C, 230 °C, 240 °C, 250 °C, 275 °C, and 300 °C temperatures for 5 min to explore conditions that could result in sample degradation. The viscosity decreased less with increasing UHMW PEO content for samples exposed to the same temperature and the viscosity decreased more with increasing exposure temperature for samples with the same UHMW PEO content. Parameters were regressed from observed data to predict the change in molecular weight via empiricisms relating the viscosity to molecular weight, shear rate, temperature, and time.

The influence of different functional areas on customers’ thermal comfort – A Field study in shopping complexes of North China

Shopping complexes are widely built for their convenience and multiple functions. However, their complex functional areas, result in significantly different thermal environments and various customers’ thermal perception. To explain the influence of functional related parameters on the thermal perception of customers in shopping complexes, we selected two typical functional related parameters, including customers’ thermal expectation level of indoor environment in their current area and the area where the customer was ten minutes before taking the survey. 851 valid questionnaires were obtained in two typical shopping complexes during July. Customers’ thermal neutral temperature, thermal preference temperature and thermal comfort temperature range were calculated in different functional areas. Customers’ thermal expectation level was quantified by using expectancy factor. The results showed that customers’ thermal expectation level in entertainment areas was the highest, followed by food courts, retail areas, and transition spaces. Customers’ thermal expectation level would influence their thermal neutral temperature and thermal sensitivity. Customers with different thermal experience differed significantly in their thermal sensation voting (p< 0.01). The highest thermal sensitivity, about 0.41/°C, was found in customers moving from high-temperature areas to low-temperature areas. These findings help to clarify how functional related parameters affect the thermal comfort of customers and provide the guidance for designing the indoor temperature in shopping complexes.

Optical temperature sensing by tuning photoluminescence in a wide (visible to near infrared) wavelength range in a Eu3+-doped Bi-based relaxor ferroelectric.

The prevalent material design principles for optical thermometry primarily rely on thermally driven changes in the relative intensities of the thermally coupled levels (TCLs) of rare-earth-doped phosphor materials, where the maximum achievable sensitivity is limited by the energy gap between the TCLs. In this work, a new, to the best of our knowledge, approach to thermometric material design is proposed, which is based on temperature tuning of PL emission from the visible to the NIR region. We demonstrate a model ferroelectric phosphor, Eu3+-doped 0.94(Na1/2Bi1/2TiO3)-0.06(BaTiO3) (NBT-6BT), which, by virtue of the contrasting effects of temperature on PL signals from the host and Eu3+ intraband transitions, can achieve a relative thermal sensitivity as high as 3.05% K-1. This model system provides a promising alternative route for developing self-referencing optical thermometers with high thermal sensitivity and good signal discriminability.

Nitrogen-rich ion salts of 1-hydroxytetrazole-5-hydrazide: a new series of energetic compounds that combine good stability and high energy performance.

High-efficiency explosives that combine high stability and excellent energy performance are one of the key directions of energetic materials research. In this study, a novel monocyclic hydroxytetrazole derivative (3) with high stability was prepared, and a series of insensitive energetic ionic salts were derived from it. Benefiting from their outstanding performance in terms of density, 3D hydrogen bonding and π-electron interactions, these salts are excellent in both detonation performance (D = 8709 to 9314 m s-1 and P = 29.9 to 35.6 GPa) and thermal stability (Td = 193.0-232.2 °C). The hydrazine salt (2) exhibits high detonation properties (D = 9314 m s-1 and P = 35.6 GPa), due to its high density (ρ = 1.71 g cm-3) and high heat of formation (ΔfH = 563.2 kJ mol-1 = 3.19 kJ g-1). In addition, the high thermal stability (Td = 232.0 °C) and low mechanical sensitivity (IS = 30 J and FS = 360 N) of 2 are also unmatched by HMX and TKX-50. These improved properties demonstrate the great promise of 2 as an insensitive high-energy explosive.

Design and Simulation of Waveguide Bragg Grating based Temperature Sensor in COMSOL

With the advancements in the domain of photonics and optical sensors, Fibre Bragg Grating (FBG) sensors, owing to their increased advantages, have been researched widely and have proved to be useful in sensing applications. Moreover, the advent of Photonic Integrated Circuits (PICs) demands the incorporation of optical sensing in waveguides, which can be integrated on silicon photonic chips. In this paper, the design of a sub-micron range Waveguide Bragg Grating (WBG) based temperature sensor with high peak reflectivity and thermal sensitivity is proposed. The flexibility of COMSOL Multiphysics software is explored to simulate the sensor and the results are verified with the analytical values calculated using MATLAB. The simulation is carried out for the proposed design having 16000 gratings and a corresponding peak reflectivity of 0.953 is obtained. A thermal sensitivity of 80 pm/K is achieved, which is approximately eight times better than that of FBG based sensor.

Assessing the risk of climate change to aquaculture: a national-scale case study for the Sultanate of Oman

Aquaculture is expanding globally and is an increasingly important component of world food security. However, climate change can impact aquaculture through a variety of mechanisms varying by location and aquaculture type with implications for future productivity. Understanding the risks that climate change poses on different culture systems in different locations is important to enable the design of targeted adaptation and resilience building actions.Here we present an aquaculture climate risk assessment framework, applied to the aquaculture sector of the Sultanate of Oman, that identifies the sensitivity and exposure of different components of the sector to climate change risk.Oman has aspirations to significantly expand aquaculture over the next decade focussing on coastal shrimp ponds, finfish sea cages, land-based recirculating aquaculture systems, and ponds and raceways. We quantify overall climate risk as the combination of four risks: (1) species’ temperature sensitivity, (2) flooding and storm surge exposure, (3) low-oxygen hazard and (4) disease vulnerability. Shrimp culture is identified as highest risk due to high exposure of shrimp ponds to flooding and storm surges, and high disease vulnerability. Seabream cage farming also faces high risk due to high thermal sensitivity and high potential of low-oxygen levels affecting sea cages. Following the risk assessment a stakeholder workshop was conducted to identify targeted adaptation measures for the different components of the sector. The framework for assessing climate risk to aquaculture demonstrated here is equally applicable at the regional, national or sub-national scale to support design of targeted resilience building actions and enhance food security.

АНАЛІЗ ТЕПЛОВИХ ЕФЕКТІВ ПРИ БАГАТООСЕРЕДКОВОМУ СТРУКТУРОУТВОРЕННІ

Abstract. The possibility of a thermal imaging technique for studying the setting of composite materials in the light of the paradigm of multifocal structure formation is analyzed. Since thermal violated observations are characterized by a high thermal sensitivity to temperature gradients up to hundredths of degrees, they make it possible to distinguish the temperature differences arising in the adjacent sections of the hardening binding. A technique for obtaining thermal images (thermograms) of a hardening composite binder is implemented. A series of thermograms of setting processes was obtained, for two of them a quantitative study was carried out, including the temperature gauge and the construction of several types of graphic mappings of the obtained patterns ‒ the normalized frequency of the distribution of the area of the binder for those temperatures and two types of densitograms ‒ radial and circular, allowing to visualize the structure of thermal foci arising in a binder. The hardening of binding materials is considered as a multistage exothermic process, in which hydration processes is accompanied by heating. The speed of heterogeneous processes associated with hydration depends, in turn, on the characteristics of the forming structure of binding materials. The observed thermal processes are considered as an indirect response, "shadow" of structure formation processes. The information consisting in this indirect response, however, is enough to make a number of conclusions on the nature of the emerging structure. The study revealed a high probability of the formation of foci near the macroscopic boundaries of the section (walls and bottom of the form), inconsistency of the structural processes, the occurrence of diverse foci of structure formation corresponding to temperature foci. The interpretation of the data obtained is the conclusion about formation of the regions of high plastic deformations near the boundaries of the contact of the foci. This regions are considered as a cluster of microscopic boundaries of the section, cracks and pores, which give rise to the structure of the destruction of the hardened material. The emergence of such areas is associated with nonynchronouspassage of structuring in different parts of the binder.

Multifunctional pressure/temperature/bending sensor made of carbon fibre-multiwall carbon nanotubes for artificial electronic application

A flexible sensor with excellent pressure, temperature, and bending sensitivity is fabricated based on the conductive skeleton material with hierarchical porous structure. The conductive skeleton material is composed of carbon fibres (CFs) and multiwalled carbon nanotubes (MWCNTs), in which lay perpendicular to each other CFs are used as conductive frames, while MWCNTs are served as bridges to connect the CFs and increase the conductive network formation. Owing to the unique structure and the conductive materials, the as-prepared sensor exhibits a high-pressure sensing performance of 42.7 kPa (0–1 kPa), fast response, relaxation times of<100 ms, wide working range of 0–60 kPa, and high stability over more than 6000 cycles. Furthermore, the fabricated sensor presents a high thermal sensitivity of 2.46 °C−1 between 30 and 40 °C, excellent bending sensitivity of 95.5 % rad−1 in the working range of 0–180°, and great flexibility (over 1000 cycles), demonstrating its potential applications in multifunctional wearable electronics.